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Effect of initial chirp on near-infrared supercontinuum generation by a nanosecond pulse in a nonlinear fiber amplifier

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Chinese Physics B 2013年第8期22卷 445-450页

作者：宋锐侯静王泽锋肖瑞陆启生 College of Optoelectronic Science and Engineering National University of Defense Technology beijing {1. of radiation medicine

Theoretical and experimental research on the effect of initial chirp on near-infrared supercontinuum generation by a nanosecond pulse in a nonlinear fiber amplifier is carded out. The complex Ginzburg-Landau equation is used to simulate the propagation of the pulse in the fiber amplifier and the results show that pulses with negative initial chirp produce the widest supercontinuum and pulses with positive initial chirp produce the narrowest supercontinuum when the central wavelength of the pump lies in the normal dispersion region of the gain fiber. A self-made line width narrowing system is utilized to control the initial chirp of the nanosecond pump pulse and a four-stage master oscillator power amplifier configuration is adopted to produce a high power near-infrared suppercontinuum. The experimental results are in good agreement with simulations which can provide some guidance on further optimization of the system in future work.

关键词： fiber laser supercontinuum initial chirp fiber amplifier

radiation Effects on the Immunological Functions and Membranes of Alveolar Macrophages of Rats

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Biomedical and Environmental Sciences 1991年第4期4卷 348-358页

作者： GONG YIFEN, Hu LIANPING AND Wu DECHANGinstitute of {1. medicine, beijing, China institute of {1. medicine Beijing China.

Alveolar macrophages (AM) from BCG activated Wistar rat were irradiated with different doses of Gamma rays in vitro. The effects of radiation on their immunological functions and membrane damage were studied. The non-specific cytotoxicity and specific phagocytosis of AM irradiated with dose of 0, 1.0, 300 and 500 Gy decreased with the increase in dose. The relative fractions of Lactate Dehydrogenase and Beta-glucuronidase (β-glu) activity in supernatant increased with the increase in dose. There was a correlation between the suppression of immunological functions and the degree of damage of cytoplasmic and lysosomal membranes of AM after irradiation. Na2SeO3, a protective agent of cell membranes, alleviated this effect on the suppressive cytotoxicity indices of irradiated AM.

关键词： radiation Effects on the Immunological Functions and Membranes of Alveolar Macrophages of Rats

Suppression of Radioactive Strontium Absorption by Sodium Alginate in Animals and Human Subjects

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Biomedical and Environmental Sciences 1991年第3期4卷 273-282页

作者： GONG YIFENG, HUANG ZHAOJIAN, QIANG MEIYU, LAN FUXING,BAI GUANG, MAO YIXIAN MA XlNPEl AND ZHANG FENGGE The institute of {1. medicine, beijing, China and The institute of Atomic Energy, beijing, China institute of {1. medicine Beijing China.

The effect of 23 sodium alginate preparations from different species of algae (Sargassum sp.) and kelp (Laminaria sp.) on reducing the absorption of strontium was studied in detail. A pilot production procedure has been established. Na alginate from S. siliquastrum was proven to be a potent agent for reducing Sr absorption, with high efficiency and virtually no toxicity. It reduced the body burden of strontium 3.3-4.2 fold in rats. Strontium absorption in human subjects was reduced by 78% ( ±8.9) or completely suppressed the increase of serum Sr at 2 h after ingestion of stable Sr in volunteers and decrease 24 h urine Sr to similar extent. No undesirable effects on gastrointestinal function was observed nor were Ca, Fe, Cu and Zn metabolism changed, both in the animal experiments and in human. It was concluded that alginate preparations derived from Sargassum species are a suitable antidote against radiostrontium absorption on a long-term basis, when added to bread at a 6% level. In cases of emergency, an alginate syrup preparation appears to be more suitable because of its rapid action.

关键词： Suppression of Radioactive Strontium Absorption by Sodium Alginate in Animals and Human Subjects

A new horizon for neuroscience:terahertz biotechnology in brain research

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Neural Regeneration Research 2025年第2期20卷 309-325页

作者： Zhengping Pu Yu Wu Zhongjie Zhu Hongwei Zhao Donghong Cui Shanghai Key Laboratory of Psychotic Disorders Shanghai Mental Health CenterShanghai Jiao Tong University School of MedicineShanghaiChina Department of Psychiatry Kangci Hospital of JiaxingTongxiangZhejiang ProvinceChina Shanghai Synchrotron radiation Facility Shanghai Advanced Research InstituteChinese Academy of SciencesShanghaiChina Key Laboratory of Interfacial Physics and Technology Shanghai Institute of Applied PhysicsChinese Academy of ScienceShanghaiChina National Facility for Protein Science in Shanghai Shanghai Advanced Research InstituteChinese Academy of SciencesShanghaiChina

Terahertz biotechnology has been increasingly applied in various biomedical fields and has especially shown great potential for application in brain *** this article,we review the development of terahertz biotechnology and its applications in the field of *** evidence indicates promising prospects for the use of terahertz spectroscopy and terahertz imaging techniques in the diagnosis of amyloid disease,cerebrovascular disease,glioma,psychiatric disease,traumatic brain injury,and myelin *** vitro and animal experiments have also demonstrated the potential therapeutic value of terahertz technology in some neuropsychiatric *** the precise underlying mechanism of the interactions between terahertz electromagnetic waves and the biosystem is not yet fully understood,the research progress in this field shows great potential for biomedical noninvasive diagnostic and therapeutic ***,the biosafety of terahertz radiation requires further exploration regarding its two-sided efficacy in practical *** review demonstrates that terahertz biotechnology has the potential to be a promising method in the field of neuropsychiatry based on its unique advantages.

关键词： biological effect brain neuron neuropsychiatry neuroscience non-thermal effect terahertz imaging terahertz radiation terahertz spectroscopy terahertz technology

STUDIES OF HAEMOPOIETIC STEM CELLS AND MICROENVIRONMENT IN CHRONIC IRRADIATED MICE

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Science China Chemistry 1983年第7期26卷 735-745页

作者：吴祖泽赵士富吴歧泰薛惠华严传双 beijing Academy of Military Medical Sciences institute of {1. medicine

Mice were irradiated at a dose rate of 70 rad per day for 25 days. Changes in properties and functions of haemopoietic stem cells and microenvironment were observed through a period of 1. months after termination of continuous irradiation. It was shown that the radiation damage of haemopoietic stem cells played an important role in the radiation-induced damage of haemopoiesis. This was further supported by the fact that transplantation of syngeneic bone marrow cells immediately after termination of continuous irradiation at 70 rad per day for 25 days would greatly improve the haemopoietic function of the irradiated mice, including the total recovery of CFU-S and numbers in the bone marrow and cell counts in the peripheral blood.

关键词： rate CFU STUDIES OF HAEMOPOIETIC STEM CELLS AND MICROENVIRONMENT IN CHRONIC IRRADIATED MICE

Gene therapy for pathological scar with hepatocyte growth factor mediated by recombinant adenovirus vector

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Science China(Life Sciences) 2003年第3期46卷 320-327页

作者：哈小琴苑宾李元敏劳妙芬吴祖泽 institute of {1. medicine Academy of Military Medical Sciences Beijing 100850 China

A complementary DNA (cDNA) encoding human hepatocyte growth factor was intro-duced into a replication-defective type 5 adenovirus (lacking E1. E3 domains) vector by homolo-gous recombination of intracellular plasmid DNA, thus a recombinant vector containing HGF (Ad-HGF) was obtained. Ad-HGF and Ad-GFP (adenovirus vector carrying green fluorescence protein gene) were expanded in 293 cells and purified by cesium chloride gradient centrifugation for large-scale preparation, then were infected to the primarily cultured scar fibroblast of rabbit ear to observe the transfer efficiency and expression level of HGF in vitro. To evaluate the effect of Ad-HGF on established scar Ad-HGF solution was injected into excessively formed scar, which bears some clinical and histologic similarities to human hypertrophic scars. The results showed that: (i) the transfer efficiency was 36.8%±1..1. on day 3 in primarily cultured scar fibroblasts treated with Ad-GFP and lasted more than 20 d; (ii) high-level expression of HGF protein was de-tected by means of ELISA in supernatant of scar fibroblasts treated with Ad-HGF, the amount of expression was 76 ng/4.0×1.5 cells on day 3; (iii) on day 32 after a single intradermal injection of Ad-HGF at different doses (8.6×1.9 pfu, 8.6×1.8 pfu, 8.6×1.7 pfu, 8.6×1.6 pfu) per scar, most of the scars in the former two dose groups were dramatically flattened, some were even similar to that of the normal skin. The value of HI (hypertrophic index) showed that there was a therapeutic effect of Ad-HGF on scars at the dose of 1.9 pfu and 1.8 pfu. Whereas no therapeutic effects were seen at lower dose (1.7 pfu and 1.6 pfu of Ad-HGF) groups. In addition, clusters of hair were ob-served to different extent on healed wound treated with Ad-HGF. Histopathologic examination re-vealed that in most healed wounds of Ad-HGF treated group, the dermal layer was thinner, the amount of fibrous tissue was much fewer, and hair follicles growth and sebaceous glands were observ

关键词： scar, hepatocyte growth factor, gene therapy, adenovirus vector.

Establishment of La-tPA/G-CSF dual transgenic mice and expression in their mammary gland

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Science China(Life Sciences) 1999年第3期42卷 330-336页

作者：卢一凡田靫邓继先程萱黄培堂 1. institute of Biotechnology Academy of Military Medicine Science 100071 Beijing China 2. Cardiovascular institute Academy of Medicine Science 100037 Beijing China

Expression vectors of human granulocyte colony stimulating factor (G-CSG ) and long acting tissue plas-minogen activator (La-tPA) in mammary gland were constructed using promoters of mouse whey acid protein gene (WAP) and sheep β-lactoglobulin gene (BLG) with sizes of 2.6 and 5 kb respectively. Two kinds of transgenic mice of G-CSF and La-tPA were produced with microinjection. The expression of G-CSF and La-tPA was achieved in mammary glands of transgenic mice, respectively. In order to establish dual transgenic mice of La-tPA /G-CSF, transgenic mice carrying G-CSF and La-tPA gene characterized with specific expression in mammary gland were mated. La-tPA/G-CSF dual transgenic mice were screened out from the hybrid offspring by Once-PCR. The co-expression of La-tPA and G-CSF in mammary gland of the dual transgenic mice was confirmed by the milk assayed and Northern blot analysis. Some parameters about the dual transgenic mice indicated that there were fewer litters than that of normal mice. The ratio of dual transgenes was 46.1.% in Fl generation, and offspring s sex ratio was normal. Hence a dual transgenic mouse model was established for the study of co-expression foreign proteins in mammary gland.

关键词： La-tPA/G-CSF mammary double transgenic mice.

Study on the Relationship Between Depletion of O^6-Methylguanine-DNA Methyltransferase and Cancer Chemotherapy

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Chinese Science Bulletin 1993年第6期38卷 501-505页

作者：陈建敏章扬培陈月能吴英范国才 beijing {1. of radiation medicine Beijing 100850 PRC

Drug resistance is still one of the major problems in cancer therapy. However, during the past several years, many efforts have been focused on reversing or depleting the molecular basis of drug resistance along with the elucidating of the mechanisms *** compounds such as 1.(4-amino-2-methyl-5-pyrimidinyl) methyl-3-(2-chloroethyl)-3-nitrosourea hydrochloride (ACNU) and 1. 3-bis-(2-chloroethyl)-1.nitrosourea (BCNU) are an important class of useful antitumor drugs. They exert their antitumor activity by alkylating the O^6 position of guanine and leading to a DNA interstrand cross-link. Introcellular O^6-methylguanine-DNA methyltransferase (O^6-MT) can repair the mentioned DNA lesions and thus plays an important role in determining the sensitivity of

关键词： O^6-methylguanine-DNA methyltransferase cancer chemotherapy ACNU streptozotocin tumor cell lines.

EMP INDUCES APOPTOSIS IN HUMAN LUNG CARCINOMA CELL LINE GLC-82

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Chinese Journal of Cancer Research 2002年第1期14卷 46-49页

作者：曹晓哲赵梅兰王德文董波 Department of Pathology Beijing Institute of Radiation Medicine Beijing

Objective: To study the effect of electromagnetic pulse (EMP) on apoptosis of human lung carcinoma cell line GLC-82. Methods: The injury changes in GLC-82 cells after irradiated by EMP (electric field intensity was 60 kV/m with 5 pulses/2 min) were analyzed by cytometry, MTT chronometry and flow cytometry. The immunohistochemical SP staining was used to determine the expressions of bcl-2 protein and p53 protein. The stained positive cells were analyzed by CMIAS-II image analysis system at a magnification 400. All data were analyzed by SPSS8.0 software. Results: EMP could obviously inhibited lung carcinoma cell line GLC-82 proliferation and increased the number of non-adherent cells. The absorbance value (A570) of MTT decreased immediately, at 0 h, 1.h and 6 h after the GLC-82 cells irradiated by EMP as compared with control group. The highest apoptosis rate was found to reach 1..38% by flow cytometry at 6 h after EMP irradiation. Down-regulation of bcl-2 expression and up-regulation of bax expression were induced by EMP. Conclusion: EMP promoted apoptosis of GLC-82 cells. At same time, EMP can down-regulate bcl-2 expression and up-regulate p53 expression in GLC-82 cells. The bcl-2 and the p53 protein may involve the apoptotic process.

关键词： EMP Apoptosis bcl-2 p53 GLC-82