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Chinese Chemical Letters 1998年第3期9卷 241-244页

作者： Li, ts Zhang, ZH Jin, ts Li, YL Hebei Univ Dept Chem Baoding 071002 Hebei Peoples R China Lanzhou Univ Natl Lab Appl Organ Chem Lanzhou 730000 Peoples R China

An easy preparation of tetrahydropyranyl (THP) ethers of alcohols and phenols with 3,4-dihydro-2H-pyran (DHP) in refluxing dichloromethane has been carried out in good to excellent yields under catalysis of anhydrous ... 详细信息

关键词： preparation tetrahydropyranyl ethers protection of hydroxy catalysis anhydrous ferrous sulfate

Studies on Retro-Michael Reaction of 1,5-Dicarbonyl Compounds

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Chinese Chemical Letters 1997年第9期8卷 765-768页

作者： Wang, JX Li, ts HEBEI UNIV DEPT CHEMBAODINGHEBEI PROVINCEPEOPLES R CHINA

The investigation of the scope and limitation of retro-Micheal reaction of 1,5-dicarbonyl compounds showed that the reaction worked well for 1,5-diketones and 1,5-ketoaldehydes but gave poor yield for 1,5-ketoesters a... 详细信息

关键词： MHz Studies on Retro-Michael Reaction of 1,5-Dicarbonyl Compounds

The　Stereochemistry　of　the　Migrating　Groups　in　the　Pyrolysis　of　Stable　Steroidal　Ozonides

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Chinese Chemical Letters 1996年第11期7卷 997-998页

作者： Yang, J Li, ts Li, YL LANZHOU UNIV STATE KEY LAB APPL ORGAN CHEMLANZHOU 730000PEOPLES R CHINA LANZHOU UNIV INST ORGAN CHEMLANZHOU 730000PEOPLES R CHINA HEBEI UNIV DEPT CHEMBAODING 071002PEOPLES R CHINA

Diacholest-13(17)-ene ozonide(1a andlb) and 4, 4-dimethyldiacholest-13 (17)-eneozonides(2a and 2b) underwent pyrolysis to afford the coressponding 17-oxo-13,14;13,17- dis14-lactones (3a and 3b)and 4.4-dimethyl-17-oxo-13,14; 13,17-disecodiacholestano-13,14-lactones(4 and 4b), respectively. The stereochemi-stry of the migratingpoups was Proven to be conserved by comparison with the Baeyer-Villiger oxidation of the corresponding 13,17-secodiacholesta-13,17-diones (5) and 4,4-dimethyl-13, 17-secodiacholesta13, 17-diones(6).

关键词： Stereochemistry the Groups

An interpolation characterization of domains of holomorphy

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Chinese Science Bulletin 1997年第23期42卷 1954-1956页

作者： Liu, ts Liu, CW Zhang, WJ Univ Sci & Technol China Dept Math Hefei 230026 Peoples R China

1 Main resultA connected open set Ω Cn is called a domain of holomorphy, if there do not exist nonemptyopen sets Ω1, Ω2 with Ω2 connected, Ω1 Ω2∩Ω, Ω2 Ω, so that for every u that is holo-morphic on Ω there is a u2 holomorphic on Ω2 with u=u2 on Ω1. This definition is compli-cated. Generally speaking, a domain of holomorphy is a domain of definition of holomorphicfunctions in the sense that there exists a holomorphic function on Ω that cannot be holomor-phically continued to any slightly large open set. Domains of holomorphy play a very importantrole in the theory of several complex variables. There are many different characterizations fordomains of holomorphy--geometrical, analytical or algebraical, each takes its different effi-cient functions in treating various concrete problems of several complex variables （see ref.[1], for example）. In this note, we use the skills of sheaf theory to give a characterization ofdomains of holomorphy by mealls of some interpolation property.

关键词： domains of holomorphy interpolation coherent analytic sheaf cohomology.

Mutational effect of the “-35” element of sorghum psbA gene promoter

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Chinese Science Bulletin 1999年第16期44卷 1474-1480页

作者： Wu, NH Fan, ts Ren, DL Chinese Acad Sci Inst Dev Biol Beijing 100080 Peoples R China

Mutations of the first position T and the third position G in TTGACA, the ' - 35' element of sorghum psbA gene promoter, were induced using chemically synthesized 20 nt oligonucleotide primer. Three mutants were produced: ATTACA, GTGACA, and ATGACA. Then the protein binding affinity of the mutants and the wild type sorghum psbA gene promoter was tested in a spinach chloroplast protein extract system. Gel retardation assay of the

关键词： sorghum ( Sorghum valgare P.) psbA gene 5’-noncodlng region site-specific mutagenesis expression control.

Morphology and biology of Cyclops scutifer Sars, 1863 in high mountain lakes of East Siberia (including Lake Amut)

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Chinese Journal of Oceanology and Limnology 2017年第2期35卷 258-264页

作者： Natalya G. SHEVELEVA Mydygma ts. ITIGILOVA Ayushcuren CHANANBAATOR Institute of Limnology Siberian Branch of Russian Academy Science Ulan-Batorskaya 3 lrkutsk 664033 Russian Federation Institute of Natural Resources Ecology and Cryology Siberian Branch of Russian Academy Science Nedorezova 16a Chita 672014 Russian Federation Institute of Biology Mongolian Academy of Science Pr. Zhukova Ulan-Bator 210351 Mongolia

Data on zooplankton from 13 high-mountain lakes of East Siberia have shown that the Holarctic copepod Cyclops scutifer Sars,1863 dominates among *** July,its abundance comprised 64%-98%of the total plankton fauna in the pelagial of these lakes,approximately 30%in the littoral zone and10%in small northern thermokarst *** measurements and morphological descriptions based on scanning microscope images are supplemented by the data on its geographic distribution and phenology.

关键词： high mountain lakes Cyclops scutifer morphology biology distribution

Nasopharyngeal carcinoma treatment paradigm after HK0501–a potential way forward

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Cancer Communications 2022年第9期42卷 801-803页

作者： Sharon S Poh Joseph ts Wee Department of Radiation Oncology National Cancer Centre SingaporeSingapore 169610Singapore Oncology Academic Clinical Program Duke-NUS Medical SchoolSingapore 169857Singapore

The Hong Kong Nasopharyngeal Carcinoma(NPC)Study Group 0501 trial(HK0501)is the first trial that directly compares induction(IC)versus adjuvant chemotherapy(AC)both given together with concurrent chemoradiation(CCRT)treatment,which long has been a contentious issue[1].Its most salient finding is that when adjusted for platinum doses and other significant factors,the timing of the chemotherapy sequence is not *** the era where chemotherapy is administered at maximum tolerated doses(MTD),the induction strategy has the advantage because of better *** the other hand,with the realization that there may be more ways to skin a cat,adjuvant metronomic chemotherapy has gained traction at the 2021 American Society of Clinical Oncology(ASCO)meeting[2]and provides an alternative to the decades’old dogma of *** chemotherapy works by exerting an anti-angiogenic effect[3-6]and also has immune effects like removing regulatory T cells(Tregs)[7]and myeloid-derived suppressor cells(MDSCs)from the tumour microenvironment[8]and causing dendritic cell maturation,which upregulates and primes the anti-tumor T cell immune response[9,10].Pediatricians are probably the first to successfully incorporate 2 years of maintenance metronomic chemotherapy in their childhood acute lymphoblastic leukaemia protocols[11]which now boast cure rates of over 90%[12].

关键词： doses Nasopharyngeal Carcinoma

Co-morbidity,not age predicts adverse outcome in clostridium difficile colitis

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World Journal of Gastroenterology 2000年第2期6卷 198-201页

作者： ts Dharmarajan M Sipalay R Shyamsundar EP Norkus CS Pitchumoni Divisions of Geriatrics Our Lady of Mercy Medical Center BronxNew YorkUSA Department of Biomedical Research Our Lady of Mercy Medical CenterBronxNew YorkUSA Divisions of Gastroenterology Our Lady of Mercy Medical Center BronxNew YorkUSA

AIM To examine whether age alone or co-morbidity is a risk factor for death in olderadults who developed Clostridium difficile(Cd)colitis during *** A retrospective,observationalstudy design was performed in our Lady ofMercy Medical Center,a 650-bed,urban,community-based,university-affiliated teachinghospital.121 patients with a positive diagnosisof Cd colitis Caged 23-97 years)were studied,and data pertinent to demographic variables,medical history,co-morbidity,physicalexamination,and laboratory results *** was examined as a continuousvariable and stratified into Age1(ts Cd colitis occurs more frequentlywith advancing age(55% of cases >80 years).However,age,per se,had no effect onmortality.A history of cardiac disease(P=0.036),recurrent or refractory infection>4weeks(P=0.007),low serum total protein(P=0.034),low serum albumin(P=0.001),antibiotic use >4 weeks(P<0.010),use of over 4 antibiotics(P=0.026),and use of certainclasses of antibiotics(P=0.035-0.004)werepredictive of *** was stronglypredicted by the use of penicillin-like antibioticsplus clindamycin,in the presence ofhypoalbuminemia,refractory sepsis,andcardiac disease(P=0.00005).CONCLUSION Cd colitis is common in the ***,unlike co-morbidity,age alonedoes not affect the clinical outcome(survival vsdeath).

关键词： clostridium difficile colitis/old age comorbidity/old age diarrhea colitis/therapy physical examination

Rabeprazole vs esomeprazole in non-erosive gastro-esophageal reflux disease: A randomized, double-blind study in urban Asia

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World Journal of Gastroenterology 2005年第20期11卷 3091-3098页

作者： KM Fock EK Teo TL Ang ts Chua TM Ng YL Tan Division of Gastroenterology Department of Medicine Changi General Hospital Singapore

AIM：Gastro-esophageal reflux disease (GERD) is becoming increasingly common in Asia. Data on the efficacy of proton pump inhibitors in patients with non-erosive GERD (NERD)in Asia is lacking. This double-blind study compared the efficacy and safety of rabeprazole with esomeprazole in relief of symptoms in patients with ***: One hundred and thirty-four patients with reflux symptoms of NERD and normal endoscopy were randomized to receive rabeprazole 10 mg or esomeprazole 20 mg once daily for 4 wk. Symptoms were recorded in a diary and changes in severity of symptoms ***: At 4 wk of treatment, rabeprazole 10 mg and esomeprazole 20 mg were comparable with regards to the primary endpoint of time to achieve 24-h symptomfree interval for heartburn 8.5 d vs9 d and regurgitation 6 d vs 7.5 d. Rabeprazole and esomeprazole were also similarly efficacious in term of patient's global evaluation with 96% of patients on rabeprazole and 87.9% of patients on esomeprazole, reporting that symptoms improved(P=NS). Satisfactory relief of day- and night-time symptoms was achieved in 98% of patients receiving rabeprazole and 81.4% of patients receiving esomeprazole. Adverse events were comparable in both groups (P = NS).CONCLUSION: Rabeprazole 10 mg has a similar efficacy and safety profile in Asians with NERD as esomeprazole 20 mg. Further study is necessary to investigate whether the small differences between the two drugs seen in this study are related to the improved pharmacodynamicpro perties of rabeprazole. Both drugs were well tolerated.

关键词： Non-erosive esophageal reflux disease New proton pump inhibitors

Vitamin B12 deficiency and gastric histopathology in older patients

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World Journal of Gastroenterology 2005年第45期11卷 7078-7083页

作者： KR Dholakia ts Dharmarajan D Yadav S Oiseth EP Norkus CS Pitchumoni Department of Medicine University Hospital of New York Medical College ValhallaNYUnited States Department of Pathology Department of Medical Research

AIM: To compare upper gastric endoscopic and histopathologic findings in older adults in the presence and absence of B12 ***: A prospective analysis of upper gastric endoscopic and gastric histopathologic findings from 30 newly identified B12-deficient patients (11 males,19 females) and 16 controls with normal B12 status (6males, 10 females) was performed. For all subjects, the indication for upper endoscopy and gastric biopsy were unrelated to B12 status. A single pathologist, blinded to B12 status, processed and interpreted the biopsy samples. Endoscopic and histopathologic findings were correlated with age, gender, hematocrit (Hct), MCV and B12 ***: The B12-deficient group had significantly lower mean serum B12 levels compared to the controls (P＜0.00005) while their mean Hct, MCV and serum albumin levels were similar. Iron deficiency (ferritinbased) was present in 21% of B12-deficient patients and intrinsic factor antibodies were present in29% (5/17) of B12-deficient patients. The endoscopic findings revealed significantly different rates of gastritis and atrophy between the B12-deficient and control groups (P= 0.017).B12-deficient patients had significantly less superficial gastritis (62% vs 94%) and significantly more atrophic gastritis (28% vs 0%) as compared to the controls (P= 0.039). Intestinal metaplasia was similar in both groups. Helicobacter pyloriinfection rates were similar in the B12-deficient patients and controls (40% vs31%).CONCLUSION: Significantly different endoscopic findings and types of gastritis could often be observed in the presence and absence of B12 deficiency. Atrophy,based on endoscopy, and atrophic gastritis, based on histopathology, suggest the presence of B12 *** histopathology is not influenced by the age,gender, Hct or MCV of the patients.

关键词： Vitamin B12 deficiency Gastrichistopathology Older adults