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Ionotropic receptors mediate olfactory learning and memory in Drosophila

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Insect Science 2024年第4期31卷 1249-1269页

作者： Md Zeeshan Ali Anushree Aarif ahsan mohammad Shamsul Ola Rizwanul Haque Jawaid ahsan Department of Biotechnology Central University of South BiharGayaBiharIndia Department of Radiation Oncology University of MichiganAnn ArborMichiganUSA Department of Biochemistry College of ScienceKing Saud UniversityRiyadhSaudi Arabia

Phenylacetaldehyde(PAH),an aromatic compound,is present in a diverse range of fruits including overripe bananas and prickly pear cactus,the two major host fruits for Drosophila *** acts as a potent ligand for the ionotropic receptor 84a(IR84a)in the adult fruit fly and it is detected by the IR84a/IR8a heterotetrameric *** role in the male courtship behavior through IR84a as an environmental aphrodisiac is of additional *** ***,two distinct kinds of olfactory receptors,that is,odorant receptors(ORs)and ionotropic receptors(IRs),perceive the odorant *** display unique structural,molecular,and functional characteristics in addition to having different evolutionary ***,olfactory cues detected by the ORs such as ethyl acetate,1-butanol,isoamyl acetate,1-octanol,4-methylcyclohexanol,*** as aliphatic esters and alcohols have been employed in olfactory classical conditioning using fruit *** underlines the participation of OR-activated olfactory pathways in learning and memory *** study elucidates that likewise ethyl acetate(EA)(an OR-responsive odorant),PAH(an IR-responsive aromatic compound)too can form learning and memory when associated with an appetitive gustatory *** association of PAH with sucrose(PAH/SUC)led to learning and formation of the long-term memory(LTM).Additionally,the Orco^(1),Ir84a^(MI00501),and Ir8a^(1)mutant flies were used to confirm the exclusive participation of the IR84a/IR8a complex in PAH/SUC olfactory associative *** results highlight the involvement of IRs via an IR-activated pathway in facilitating robust olfactory behavior.

关键词： appetitive conditioning Drosophila melanogaster ethyl acetate ionotropic receptors learning and memory phenylacetaldehyde

Robust design of sliding mode control for airship trajectory tracking with uncertainty and disturbance estimation

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Journal of Systems Engineering and Electronics 2024年第1期35卷 242-258页

作者： WASIM Muhammad ALI ahsan CHOUDHRY mohammad Ahmad SHAIKH Inam Ul Hasan SALEEM Faisal Department of Aeronautics and Astronautics Engineering Institute of Space TechnologyIslamabad 44000Pakistan Department of Electrical Engineering University of Engineering and TechnologyTaxila 47080Pakistan Department of Measurements and Control Systems Silesian University of TechnologyGliwice 44-101Poland The Joint Doctoral School Silesian University of TechnologyGliwice 44-100Poland

The robotic airship can provide a promising aerostatic platform for many potential *** applications require a precise autonomous trajectory tracking control for *** has a nonlinear and uncertain *** is prone to wind disturbances that offer a challenge for a trajectory tracking control *** paper addresses the airship trajectory tracking problem having time varying reference path.A lumped parameter estimation approach under model uncertainties and wind disturbances is opted against distributed *** uses extended Kalman filter(EKF)for uncertainty and disturbance *** estimated parameters are used by sliding mode controller(SMC)for ultimate control of airship trajectory *** comprehensive algorithm,EKF based SMC(ESMC),is used as a robust solution to track airship *** proposed estimator provides the estimates of wind disturbances as well as model uncertainty due to the mass matrix variations and aerodynamic model *** stability and convergence of the proposed method are investigated using the Lyapunov stability *** simulation results show that the proposed method efficiently tracks the desired *** method solves the stability,convergence,and chattering problem of SMC under model uncertainties and wind disturbances.

关键词： airship chattering extended Kalman filter(EKF) model uncertainties estimation sliding mode controller(SMC)

Prevalence of Depression in Pre-Dialytic Chronic Kidney Disease Patients Attending at a Tertiary Care Hospital in Bangladesh

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Journal of Biosciences and Medicines 2020年第12期8卷 135-148页

作者： A. K. M. Shahidur Rahman mohammad Shamsul ahsan mohammad kamrul ahsan A. B. M. Mobasher Alam Tanvir Rahman Shahida Mullah Md. Mustafizur Rahman Salahuddin Feroz Amir mohammad Kaiser Md. Shariful Haque Department of Nephrology Bangabandhu Sheikh Mujib Medical University (BSMMU) Dhaka Bangladesh Department of Nephrology Bangabandhu Sheikh Mujib Medical University (BSMMU) Dhaka Bangladesh Holy Family Red Crescent Medical College Hospital (HFRCMCH) Dhaka Bangladesh Department of Nephrology Rangpur Medical College Hospital (RMCH) Rangpur Bangladesh Department of Nephrology United Hospital Limited Dhaka Bangladesh Department of Medicine Sarkari Karmachari Hospital Dhaka Bangladesh Department of Nephrology Sheikh Hasina Medical College Tangail Bangladesh Sheikh Hasina National Institute of Burn and Plastic Surgery Dhaka Bangladesh Department of Nephrology & Dialysis Gonoshaystha Somazvittik Medical College and Gonoshaystha Nagar Hospital Dhaka Bangladesh Department of Nephrology Shaheed M. Monsur Ali Medical College Sirajgonj Bangladesh

Background: Depression is a common and serious medical illness around the world. It occurs more frequently in patients with chronic illness than in the general population. It is a common psychiatric problem in patients with chronic kidney disease (CKD). Objective: To assess the level of depression in pre-dialytic CKD patients attending at a tertiary care hospital in Bangladesh. Methodology: This cross sectional study was conducted at Department of Nephrology, Bangabandhu Sheikh Mujib Medical University (BSMMU), Dhaka, Bangladesh from January 2020 to June 2020. A total of 100 pre-dialytic CKD patients were selected by convenience sampling technique and their level of depression was assessed by Zung Self-Rating Depression Scale (ZSDS). Data were collected by existing questionnaire with face to face interview and analyzed by statistical test. Results: The mean age of the participants was 49.70 ± 11.80 years. Among them 64% were male, 95% were muslim, 98% were married, 65% were completed secondary/above higher secondary level education, 65% were unemployed and 55% were lived in urban area. It was observed that 65% participants were economically dependent to their family, only 6% were engaged in regular exercise, 14% had family history of depression, 8% were smoker and 12% were alcohol/drug abuser. According to the Zung Self-Rating Depression Scale (ZSDS) we found 29% participants were mildly depressed, 39% participants were moderately depressed and 18% participants were severely depressed. Prevalence of depression was 86% in pre-dialytic CKD patients. Of them, 7% was in CKD stage-I, 17.4% was in CKD stage-II, 19.8% was in CKD stage-III, 22.1% was in CKD stage-IV and 33.7% was in CKD stage-V. Conclusion: Depression is highly prevalent in pre-dialytic CKD patients and more frequent in the advanced stages of CKD.

关键词： Chronic Kidney Disease (CKD) Depression Zung Self-Rating Depression Scale (ZSDS)

Liver Function Tests in Patients of Acute Leukemia before and after Induction Chemotherapy

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Journal of Biosciences and Medicines 2020年第2期8卷 110-121页

作者： Tahmidul Islam A. K. M. Shahidur Rahman Md. kamrul Hasan Ferdous Jahan Manik Chandra Mondal Sheuly Ferdoushi Sabrina Alam mohammad kamrul ahsan Jannatut Tasnim Sharaban Tohura Department of Biochemistry Bangabandhu Sheikh Mujib Medical University (BSMMU) Dhaka Bangladesh Department of Nephrology Bangabandhu Sheikh Mujib Medical University (BSMMU) Dhaka Bangladesh Department of Haematology Colonel Malek Medical College Manikganj Bangladesh Department of Laboratory Medicine Bangabandhu Sheikh Mujib Medical University (BSMMU) Dhaka Bangladesh Department of Biochemistry TMSS Medical College Bogura Bangladesh Holy Family Red Crescent Medical College Hospital (HFRCMCH) Dhaka Bangladesh Department of Biochemistry Popular Medical College Dhaka Bangladesh Sadar Hospital Lalmonirhat Bangladesh

Background: Patients of acute leukemia require careful assessment of liver function prior to start chemotherapy to determine which drugs may be appropriate or to be modified. Post chemotherapy abnormalities of liver function tests may be due to drugs or due to disease process itself. Objective: To evaluate the status of liver function in acute leukemia patients before and after induction chemotherapy. Methodology: This was a prospective cross-sectional study conducted in the Department of Biochemistry, Dhaka Medical College, Dhaka, Bangladesh from January 2017 to December 2017 on fifty (50) newly diagnosed patients of acute leukemia who fulfilled the selection criteria. Blood samples for serum total bilirubin, alanine transaminase (ALT) and aspartate transaminase (AST) were collected before chemotherapy (Day 1) and after induction chemotherapy on 14th day and 30th day. Serum ALT and AST were measured by kinetic method and serum total bilirubin was measured by DMSO method. Data were analyzed and compared by statistical tests. Result: In this study, the mean level of serum total bilirubin before chemotherapy at day 1 was 0.89 ± 0.64 mg/dl. It was significantly (p Conclusion: It is concluded that serum total bilirubin, ALT and AST increase in response to chemotherapeutic drugs during treatment of acute leukemia.

关键词： Acute Leukaemia Alanine Transaminase (ALT) Aspartate Transaminase (AST) Bilirubin Chemotherapy

Outcomes of Layered versus Mass Closure in Transverse Incision during Emergency Laparotomy in Children

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Journal of Biosciences and Medicines 2020年第8期8卷 180-193页

作者： Khandoker Moynul Hasan Shahnoor Islam Md. Ashraf Ul Huq Muhammed Moinul Huque Shah Md. Rezaul Karim mohammad Shafiul Azam Md. Iqbal Hossain Talukder Sharmin Ara Begum mohammad kamrul ahsan A. K. M. Shahidur Rahman Department of Pediatric Surgery Dhaka Medical College Hospital (DMCH) Dhaka Bangladesh Department of Pediatric Urology Dhaka Medical College Hospital (DMCH) Dhaka Bangladesh Department of Surgery Sheikh Hasina Medical College Hospital Habiganj Bangladesh Department of Urology National Institute of Kidney Diseases and Urology (NIKDU) Dhaka Bangladesh Department of Surgery Sheikh Hasina Medical College Hospital Tangail Bangladesh Department of Anesthesiology National Institute of Traumatology and Orthopedic Rehabilitation (NITOR) Dhaka Bangladesh Holy Family Red Crescent Medical College Hospital (HFRCMCH) Dhaka Bangladesh Department of Nephrology Bangabandhu Sheikh Mujib Medical University (BSMMU) Dhaka Bangladesh

Background: The value of laparotomy closure technique may be measured by the incidence of early and late wound complications. The best laparotomy closure technique should be less time consuming, easy and cost-effective, while preventing both early and late complications. Objective: To compare the outcomes of layered versus mass closure in transverse incision during emergency laparotomy in children. Methods: This prospective comparative study was conducted at Department of Pediatric Surgery, Dhaka Medical College Hospital (DMCH), Dhaka, Bangladesh from July 2016 to June 2018. A total of 60 pediatric age cases that underwent laparotomy were included in this study. Cases were randomly allocated into two groups;30 patients were in Group A (Layered closure) and 30 patients were in Group B (Mass closure). The outcome variables were time required for wound closure, wound infection, wound dehiscence and incisional hernia. Data were analyzed and compared by statistical tests. Results: The mean age of Group A and Group B patients were 31.08 ± 30.25 months and 34.70 ± 42.73 months respectively (p = 0.706). The ratio between male and female subject was 1.1:1 in Group A and 3.3:1 in Group B. The common diseases of the study patients who underwent laparotomy were intussusceptions, intestinal obstruction due to bands and adhesion, perforated appendix and perforation of small intestine due to blunt trauma respectively. Mean wound closure time was significantly less in mass closure group [28.20 ± 2.17 minutes in layered closure group and 18.80 ± 1.67 minutes in mass closure group, (p ≤ 0.001)]. Wound infection rate, incidence of superficial wound dehiscence, and incisional hernia were relatively less in mass closure group, however, the differences were not statistically significant (p = 0.053, p = 0.095 and p = 0.301 respectively). There was no complete wound dehiscence in Group A, but that was in 1 (3.3%) patient i

关键词： Laparotomy Layered Closure Mass Closure

Incidence, Risk Factors and Short Term Outcome of Acute Kidney Injury among Patients with Acute Coronary Syndrome

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Journal of Biosciences and Medicines 2020年第5期8卷 177-188页

作者： Md. Kabir Hossain Muhammad Rafiqul Alam Asia Khanam A. K. M. Shahidur Rahman Rafi Nazrul Islam Syed Fazlul Islam mohammad kamrul ahsan S. K. Mamun-Ar-Rashid Tanvir Rahman Md. Nazmul Hasan Department of Nephrology Bangabandhu Sheikh Mujib Medical University (BSMMU) Dhaka Bangladesh Department of Nephrology & Dialysis BIRDEM General Hospital Dhaka Bangladesh Holy Family Red Crescent Medical College Hospital (HFRCMCH) Dhaka Bangladesh Department of Medicine Khulna Medical College Hospital Khulna Bangladesh Department of Nephrology United Hospital Limited Dhaka Bangladesh Department of Cardiology Ad-din Medical College Hospital Dhaka Bangladesh

Background: Cardio-renal syndrome is the leading cause of death globally. Acute kidney injury (AKI) is a major complication among patients admitted in Coronary Care Unit (CCU) with acute coronary syndrome (ACS). AKI in ACS patients is associated with higher morbidity, mortality and prolong hospital stay. Objective: To determine the incidence, risk factors and short term outcome of acute kidney injury (AKI) among the patients admitted in CCU with ACS. Methods: This cross sectional study was conducted at Department of Nephrology, Bangabandhu Sheikh Mujib Medical University (BSMMU), Dhaka, Bangladesh from January 2013 to December 2013. Following selection criteria a total of two hundred (200) patients with ACS were studied. AKI was defined according to the KDIGO guideline and further categorized by RIFLE criteria. Data of patients with AKI and those without AKI were analyzed and compared by statistical tests. Results: Majority of the study patients were male (79.5%). AKI was developed in 40 of the 200 study patients (20.0%). The mean (±SD) age of the study patients was 60.1 ± 11.1 years in patients with AKI and 55.9 ± 10.1 years in patients without AKI. Our data analysis showed that older age (>65 years), diabetes mellitus, dyslipidemia and smoking were significantly correlated to the development of AKI. Mortality was significantly high in AKI group (7.15%) compared to no AKI group (1.25%). Out of 27 patients who achieved renal recovery most (80.8%) belonged to risk class. Severity of AKI showed significant effect on renal recovery and final outcome. Conclusion: This study demonstrated that, incidence of AKI among patients with ACS was 20%. Elderly patients, diabetes mellitus, dyslipidemia, and exposure to smoking were significantly associated with development of AKI in ACS.

关键词： Acute Kidney Injury (AKI) Acute Coronary Syndrome (ACS) Cardio-Renal Syndrome

Ocular Fundus Abnormalities in Pre-Dialytic Chronic Kidney Disease Patients

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Journal of Biosciences and Medicines 2019年第11期7卷 20-35页

作者： mohammad kamrul ahsan Muhammad Rafiqul Alam Asia Khanam A. H. Hamid Ahmed Md. Omar Faroque K. B. M. Hadiuzzaman A. K. M. Shahidur Rahman Rafi Nazrul Islam Manik Chandra Mondal Md. Azizur Rahman Holy Family Red Crescent Medical College Hospital (HFRCMCH) Dhaka Bangladesh Department of Nephrology Bangabandhu Sheikh Mujib Medical University (BSMMU) Dhaka Bangladesh Department of Nephrology & Dialysis BIRDEM General Hospital Dhaka Bangladesh Bangladesh Eye Hospital & Institute Dhaka Bangladesh

Background: Chronic kidney disease (CKD) affects 10% - 16% of the adult population. Although ocular findings related to renal insufficiency include cataract, conjunctival calcification, lid edema, conjunctival pallor and xanthalesma, by far the most important is retinopathy. Objective: To evaluate the ocular fundus abnormalities in pre-dialytic chronic kidney disease patients of the adult population. Methodology: This cross-sectional observational study was conducted in the Department of Nephrology, Bangabandhu Sheikh Mujib Medical University (BSMMU), Dhaka, Bangladesh from April 2012 to March 2014. A total of 100 hospital admitted CKD patients were purposively selected for this study. Age, gender, blood pressure, Body Mass Index (BMI), 24 hours Urinary Total Protein (UTP), haemoglobin level, serum creatinine, serum cholesterol, serum triglyceride and color fundus photography findings of both eyes were recorded for each patient. Inter-group comparisons were made between patients with retinopathy and those without retinopathy. Results: Out of 100 adult non-dialytic CKD patients, 43 (43%) had ocular fundus abnormalities, among them 27 (62.8%) were male and 16 (37.2%) were female. The risk of development of retinopathy was significantly higher among older patients (p = 0.006), those with low haemoglobin level (p = 0.0001) and high blood pressure. Retinopathy was significantly (p = 0.0001) increased with reduction of e-GFR. There was no relationship between BMI and high serum triglyceride level with retinal abnormality. Among 43 (43%) patients with retinal abnormality, 30 (69.76%) patients showed only hypertensive retinopathy and 5 (11.6%) patients showed only diabetic retinopathy. Mixed hypertensive and diabetic retinopathy was found in 8 (18.6%) patients. Maculopathy was seen in 11 (25.58%) patients, of whom 3 (6.98%) had hypertensive retinopathy and 8 (18.87%) had diabetic retinopathy. Optic atrophy was seen in 2 (4.6%) patients and drusen like retinal deposits were

关键词： Chronic Kidney Disease (CKD) Ocular Fundus Retinopathy

Effects of Combined Spinal Epidural Anaesthesia and Spinal Anaesthesia on Peri-Operative Pulmonary Status in Geriatric Patients in Lower Extremity Surgery

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Journal of Biosciences and Medicines 2020年第10期8卷 132-147页

作者： Sharmin Ara Begum A. K. M. Akhtaruzzaman Dilip Kumar Bhowmick Debabrata Banik Md. Afzalur Rahman A. K. M. Shahidur Rahman Md. Saydur Rahman Khandoker Moynul Hasan mohammad kamrul ahsan Md. Imrul Islam Muhammad Shamsul Arefin Tahmidul Islam Department of Anaesthesiology National Institute of Traumatology and Orthopedic Rehabilitation (NITOR) Dhaka Bangladesh Department of Anaesthesia Analgesia and Intensive Care Medicine Bangabandhu Sheikh Mujib Medical University (BSMMU) Dhaka Bangladesh Department of Neuro-Anaesthesia National Institute of Neurosciences and Hospital (NINS) Sher-e-Bangla Nagar Agargaon Dhaka Bangladesh Department of Nephrology Bangabandhu Sheikh Mujib Medical University (BSMMU) Dhaka Bangladesh Department of Anaesthesia Asgor Ali Hospital Dhaka Bangladesh Department of Pediatric Surgery Shaheed Suhrawardy Medical College and Hospital Dhaka Bangladesh Holy Family Red Crescent Medical College Hospital (HFRCMCH) Dhaka Bangladesh Department of Anaesthesiology and Intensive Care Unit (ICU) Rajshahi Medical College Hospital (RMCH) Rajshahi Bangladesh Department of Biochemistry Bangabandhu Sheikh Mujib Medical University (BSMMU) Dhaka Bangladesh

Background: Lower extremity surgeries performed in elderly people usually have high prevalence of peri-operative medical problems related to anaesthesia. The overall objective of peri-operative care of geriatric population is to fast recovery from anaesthesia and avoid functional decline. Objective: To compare the peri-operative pulmonary status of combined spinal epidural anaesthesia (CSEA) and spinal anaesthesia (SA) in geriatric patients underwent lower extremity surgeries. Methods: This prospective comparative study was conducted at Department of Anaesthesia, Analgesia and Intensive Care Medicine, Bangabandhu Sheikh Mujib Medical University (BSMMU), Dhaka, Bangladesh from July 2016 to June 2018. A total of 70 geriatric cases that underwent lower extremity surgeries were included in this study. Cases were randomly allocated into two groups;35 in Group A (CSEA) and 35 in Group B (SAB). The different outcome variables between the groups like-duration of anaesthesia, respiratory rates (RR), oxygen saturation (SpO2), end tidal CO2 (EtCO2), peak expiratory flow rate (PEFR), breath holding test (BHT), peri-operative side effects of anaesthesia and post-operative visual analogue score (VAS) were analyzed and compared by statistical tests. Results: The mean age, weight, BMI of Group A and Group B patients were not significantly different (p > 0.05). No significant differences were observed in duration of surgery, gender and ASA grade between the groups (p > 0.05). Mean duration of anaesthesia, mean time to achieve target level of sensory block and mean time to achieve complete motor block were significantly higher in Group A (p 2, PEFR and BHT of both groups were not significantly different (p > 0.05). Peri-operative side effects of anaesthesia and post-operative VAS were significantly less in group A patients (p <

关键词： Combined Spinal Epidural Anaesthesia (CSEA) Geriatric Patients Spinal Anaesthesia (SA)

Non-Diabetic Renal Disease in Patients with Type 2 Diabetes Mellitus with Proteinuria

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Journal of Biosciences and Medicines 2019年第12期7卷 68-78页

作者： Manik Chandra Mondal Rana Mokarrom Hossain K. B. M. Hadiuzzaman Md. Omar Faroque Shah Md. Zakir Hossain A. K. M. Shahidur Rahman Fahad Al Shatil Ashrafee Popy Sarker Abu Zafor Md. Salahuddin mohammad kamrul ahsan Department of Nephrology Bangabandhu Sheikh Mujib Medical University (BSMMU) Dhaka Bangladesh Department of Orthodontics and Dento-Facial Orthopaedics Dhaka Dental College and Hospital (DDCH) Dhaka Bangladesh Department of Nephrology Mymensingh Medical College Hospital (MMCH) Mymensingh Bangladesh Holy Family Red Crescent Medical College Hospital (HFRCMCH) Dhaka Bangladesh

Background: Diabetes mellitus (DM) is the leading cause of end stage renal disease (ESRD) worldwide. Although DM with proteinuria is the ultimate result of diabetic nephropathy (DN), a wide spectrum of non-diabetic renal diseases (NDRD) can occur in such patients. Objective: To observe the frequency and histological pattern of NDRD in diabetic patients with proteinuria and to explore their association with clinical and laboratory parameters. Methods: This cross-sectional study was conducted in the Department of Nephrology, Bangabandhu Sheikh Mujib Medical University (BSMMU), Dhaka, Bangladesh from April 2016 to September 2017. In this study a total of 38 cases of DM with proteinuria (>1 gm/24-hour) were selected purposively. Renal biopsy was done in all patients. Based on histological findings they were categorized into two groups;Group 1 with NDRD and Group II with DN. Their clinical and laboratory parameters were analyzed and compared. Results: Among the total study subjects, 21 (55.3%) were male and 17 (44.7%) were female, mean (±SD) age 43.45 ± 9.99 years in the NDRD group and 41.57 ± 9.50 years in the DN group. Thirty one cases (81.6%) out of thirty eight had NDRD and seven (18.4%) cases had isolated DN;therefore more than two third cases had NDRD. Duration of DM was found to be significantly shorter (p = 0.004) in the NDRD group. Diabetic retinopathy was present in 12.9% cases in NDRD group vs. 57.1% cases in DN group (p = 0.025). Frequency of microscopic hematuria was significantly higher (90.3%) in NDRD patients (p = 0.002). Conclusion: The frequency of NDRD in type 2 diabetic patients other than diabetic nephropathy is relatively high. Membrano proliferative glomeru-lonephritis and membranous nephropathy are more common in NDRD. Absence of diabetic retinopathy, presence of hematuria and shorter duration of DM are markers associated with NDRD in type 2 DM, which are important indicators for renal biopsy in diabetic patients with proteinuria.

关键词： Diabetes Mellitus (DM) Diabetic Nephropathy (DN) Non-Diabetic Renal Disease (NDRD) Renal Biopsy