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91.
92.
本文以腺苷酸为测定物,探讨了以国产自动平衡记录仪为高效液相色谱记录并定量分析结果的方法。结果表明,从自动平衡记录上得到峰形、计算结果均与原机所带积分仪的一致。其稳定性、灵敏度和线性响应均能达到高效液相色谱检测器的要求,是一种可以代替积分仪分析结果的经济、可靠的方法。  相似文献   
93.
用病例对照研究方法探索建德县罹患流行性出血热(EHF)的危险因素。经临床诊断和血清学证实的97例EHF病例,按年龄、性别和住同一医院与其他疾病病人作1:1配对调查。条件logistic回归模型分析,发现村中曾有EHF史、外出他县、野宿和直接接触鼠类四个因素是罹患EHF的危险因素,其相对危险度分别为35.67、11.94、18.18和7.36。病例家属隐性感染率(4.95%)与对照家属隐性感染率(5.12%)相似;病例与对照家中捕获的鼠类及其EHF抗体、抗原阳性率无显著性差异。  相似文献   
94.
检测198例各型乙肝患者血小板功能的五个项目:血小板总数、粘附试验、聚集试验、血块退缩、血小板第3因子有效性,发现各期乙肝患者血小板功能的异常有显著性差异(P<0.01).并提示乙肝患者除有血小板数量的改变外,还有质量的改变,因此,全面的血小板功能检测可作为估计乙肝患者肝损害程度的辅助指标.  相似文献   
95.
Total fluorescence from arterial tissue is influenced by three factors: the absorption coefficient of tissue at a specific excitation wavelength, the laser excitation power and the fluorescence coefficient which is related to chemical species in tissue. These various influences were demonstrated by the following experimental results in vitro: (1) the effect of increasing power on fluorescence intensity, (2) the total fluorescence intensity in normal aorta and plaque and (3) the effect of a chromophore such as β-carotene on total fluorescence intensity. The fluorescence intensity of normal artery is an incremental function of laser excitation power, and the fluorescence emission from normal artery compared to fluorescence emission from plaque is significantly different at the same excitation power. The total fluorescence of normal artery was measured to be twice as great as that of atheromatous plaque (relative mean ratio of 2.58±0.46 compared to unity,p<0.0002 at 488 nm; relative mean ratio of 2.57±0.51 compared to unity,p<0.0009 at 514 nm). The total fluorescence emission decreases with the increase of β-carotene content in arterial tissue (R=0.97). These emission differences, when intensified by an exogenous chromophore of β-carotene, may provide an improved guidance signal for diagnosis of plaque from normal artery during laser angioplasty procedures.  相似文献   
96.
TuberculosisandSchistosomiasisarethemajorcontagiousdiseaseswhicharethemostdangeroustothepeople’shealth Inordertogetridofthem ,wemustlookforamoreusefulvaccine Bythetech niquesofmolecularbiology ,2 6 0 0 0DaGlutathionStransferase (GST) genewasclonedintotheE coli MycobacteriumtransferringandexpressionvectorpBCG 2 0 0 0totransformittoMycobacteriumsmeg matismc2 15 5 (MS)andBCGseparatelyinordertoconstructrMS Sj2 6GSTvaccineandrBCG Sj2 6GSTvaccine Inthisstudy ,theBALB/cmicewereimmu niz…  相似文献   
97.
用乙二醇法诱导大鼠产生草酸钙结石,用45~Ca示踪测定法了解中草药复方制剂(PESM)对草酸钙结石形成的抑制作用。结果显示,实验组肾脏放射性强度明显减少(实验组3.47±3.52cpm/mg,对照组10.89±14.24cpm/mg)。干肾重量明显下降(实验组306.0±47.0mg,对照组343.1±59.4mg),说明PESM能明显抑制肾脏草酸钙结石的形成。  相似文献   
98.
Sixty-seven cases of chronic hepatitis were treated with Radix Astragali. After treatment (2-month course), the clinical improvement rate in 38 cases of the Stagnation of the Liver-Qi and Deficiency of the Spleen type was 92.1%, and in 26 cases of the Deficiency of Liver Yin and Kidney Yin type was 88.5%, more effective than in the control group (P<0.05). The regulative effect to the levels of serum hormone was observed in the patients of the Stagnation of the Liver-Qi and Deficiency of the Spleen type treated with this medicine. The results showed that the levels of serum triiodothyronine, estradiol (female) and testosterone (male) were increased after treatment (1.40±1.38 ng/dl, 129.30±1.23 pg/ml and 496.24±1.47 ng/dl). Pre-treatment levels were 1.22±1.49 ng/dl, 104.60±1.45 pg/ml and 398. 17±1.55 ng/dl respectively (P<0.05); however, the level of serum prolactin (2.75±4.46 ng/ml) was lower after treatment than before treatment (3.20±3.82 ng/ml,P<0.05). No obvious changes were observed in the levels of serum follicle stimulating hormone, luteinizing hormone, thyroid stimulating hormone, thyroxine, triiodothyronine uptake ratio and cortisol after treatment.  相似文献   
99.
BACKGROUND: It has been demonstrated that mild hypothermia has obvious protective effect on both whole and local cerebral ischemia. However, the definite mechanism is still unclear for the brain protection of mild hypothermia on cerebral edema, inhibiting inflammatory reaction, stabilizing blood brain barrier, etc. OBJECTIVE: To investigate the effect of mild hypothermia on the expression of vascular endothelial growth factor and the infarct volume after cerebral ischemia in rats, and analyze the brain protective mechanism of mild hypothermia. DESIGN: A randomized grouping and controlled animal trial. SETTING: Department of Neurology, People's Hospital of Yunyang Medical College. MATERIALS: Twenty adult male SD rats of clean degree, weighing (250±30) g, were provided by the animal experimental center, School of Medicine, Wuhan University. The kits for SP immunohistochemistry were purchased from Beijing Zhongshan Golden Bridge Biotechnology Co., Ltd. METHODS: The experiments were carried out in the laboratory of Department of Neurology, Renmen Hospital of Wuhan University from May to July 2005. ① The 20 rats were divided randomly into normal temperature group (n =10) and mild hypothermia group (n =10). Models of permanent middle cerebral artery occlusion were established with modified nylon suture embolization. The rats were assessed with the Longa standards: 0 point for without nerve dysfunction; 1 for mild neurological deficit (fore claws could no extend completely); 2 for moderate neurological deficit (circling towards the affected side); 3 for severe neurological deficit (tilting towards the affected side); 4 for coma and unconscious; 1-3 points represented that models were successfully established. The rats of the normal temperature group were fed at room temperature, and those in the mild hypothermia group were induced by hypothermia from 2 hours postoperatively, and the rectal temperature was kept at 34-35 ℃ for 72 hours. ② Measurement of infarct volume: All the rats were anesthetized by intraperitoneal injection overdose sodium pentobarbital 7 days postoperatively, and then the heads were cut down to harvest brain. The brain tissues were placed into -20 ℃ refrigerator for 20 minutes, coronal sections of 2 mm were prepared. The infarct sites were not stained, whereas normal brain tissues were stained as red. The infarct volumes were calculated by using MPLAS-500 multimedia color pathological image&&word analytical system. ③ Counting positive cells of vascular endothelial growth factor protein: The brains were harvested by cutting heads, then coronal sections of 2 mm were prepared. Routine dehydration, hyalinization, wax immersion and embedding were performed, then the detected with SP immunohistochemistry, the kits were purchased from Beijing Zhongshan Golden Bridge Biotechnology Co., Ltd. The cells whose cytoplasm was yellow-brown were positive ones, a single sample as a unit, peri-ischemic site and ischemic core were selected, and the corresponding sites in controlateral hemisphere were taken as controls. Five visual fields were selected from each site to be observed under microscope, the cells were counted, and the average number of positive cells was calculated in each group. The numbers of positive cells were determined with the image analytical apparatus. MAIN OUTCOME MEASURES: Number of the positive cells of vascular endothelial growth factor protein; Infarct volume of rat brain tissue. RESULTS: All the 20 rats were involved in the analysis of results. ① Number of positive cells of vascular endothelial growth factor protein in brain tissue: It was obviously lower in the mild hypothermia group than in the normal temperature group [(24.02±5.05), (36.07±2.69) cells/high power visual field, P < 0.01]. ② Comparison of infarct volume of brain tissue: After MCAO, it was obviously smaller in the mild hypothermia group than in the normal temperature group [(153.25±23.14), (253.45±36.21) mm3, P < 0.01]. CONCLUSION: Mild hypothermia can inhibit the expression of vascular endothelial growth factor and decrease the volume of cerebral infarction. The inhibition of mild hypothermia on the expression of vascular endothelial growth factor may be one of the brain protective mechanisms.  相似文献   
100.
To set up a method of amplification for the whole CagA gene of Helicobacter pylori and its fingerprinting by restriction fragment length polymorphism(RFLP),nested PCR was employed in combination with TD-PCR to amplify the gene and EcoRI and Hind Ⅲ were used to generate the RFLP fingerprinting.Target DNA fragments from 13 of 20 samples were successfully amplified and the relevant RFLP fingerprintings were obtained.It is concluded that the method can be used to amplify the whole CagA gene and CagA gene has apparent diversity of RFLP profile.  相似文献   
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