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1.
双波长紫外分光光度法测定贝母中腺苷和胸苷的含量   总被引:4,自引:0,他引:4  
将4种贝母的甲醇提取物经薄层色谱法粗分离后,直接用双波长紫外分光光度法测定其含量。结果表明,该方法线性关系好,腺苷和胸苷标准曲线的相关系数均为0.9999,同时也发现平贝、炉贝和伊贝中腺苷都占核苷总量60%以上,而浙贝中仅占约40%,提示贝母生药的抗凝血活性可能与贝母中核苷类化合物的种类和含量的差别有关。  相似文献   
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Background. Increased cardiovascular disease risk is very well known in nephrotic syndrome. Coronary flow reserve measurement by trans-thoracic echocardiography reflects coronary microvascular and endothelial function. However, diastolic filling abnormalities by echocardiography may indicate diastolic dysfunction. Our aim was to evaluate endothelial and diastolic functions by trans-thoracic echocardiography in nephrotic syndrome. Methods. Eighteen patients with nephrotic syndrome (five females, 34 ± 17 years) and 30 controls (10 females, 35 ± 10 years) were evaluated in this cross-sectional observational study. Age, weight, lipid profile, glucose, blood urea nitrogen, creatinine, serum albumin, total protein, C-reactive protein, erythrocyte sedimentation rate, blood pressures, 24-hour urine volume, and protein were recorded. Glomerular filtration rate was estimated by Cockcroft-Gault Formula. Doppler flow and other echocardiographic parameters were measured by Vivid 7 echocardiography. Results. Coronary flow reserve was significantly lower in patients than controls (p < 0.001) and was negatively correlated with proteinuria (p < 0. 001), creatinine levels (p?=?0.03), total cholesterol (p?=?0.02), C-reactive protein (p?=?0.02), and erythrocyte sedimentation rate (p?=?0.005). E/A ratio was significantly lower in patients than in controls (p?=?0.005). DT was significantly higher in patients than in controls (p?=?0.01) and isovolumic relaxation time was similar in both groups. Conclusion. Coronary flow reserve and left ventricular diastolic filling are significantly impaired in nephrotic syndrome. Proteinuria, serum creatinine, total cholesterol and inflammation may have all contributory effects on endothelial dysfunction. Early evaluation of patients with nephrotic syndrome should include coronary flow and diastolic function by echocardiography.  相似文献   
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We evaluated the histopathological changes occurring in corneal endothelium after intracameral injection ropivacaine into rats. Intracamerally administered ropivacaine in 1, 0.5, and 0.1% concentrations resulted in impairment of hexagonal structure of corneal endothelial cells and inter-cellular junctions, destruction of microvilli on the cell surface, roughness of cell borders, picnotic nucleus, diffuse vacuolization, and crystalysis in mitochondria. The authors have stated that they do not have a significant financial interest or other relationship with any product manufacturer or provider of services discussed in this article. The authors also do not discuss the use of off-label products, which include unlabeled, unapproved, or investigative products or devices.  相似文献   
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BACKGROUND: Although seasonal variation of birth weight has been reported previously, contributing factors such as the meteorological factor and its specific period of exposure remain unclear. AIM: To investigate the effect of season on birth weight and to determine the meteorological factor and its specific period of exposure which can contribute to any seasonal variation in birth weight. METHODS: Retrospective analysis of 3333 singleton live births after 36 completed weeks of pregnancy. Maternal age, parity, route of delivery, sex and individual meteorological variables for the first, second, and third trimesters of each pregnancy were analysed using multiple regression analysis with the birth weight as the dependent variable. RESULTS: A seasonal pattern was observed with lowest birth weights in women who had their last menstrual periods in summer and autumn. Upon multiple regression analysis, sex, parity, mode of delivery, and the temperature which the mother was exposed to in the second trimester were the independent determinants of birth weight. CONCLUSION: Exposure to low outdoor ambient temperature in the midtrimester can be associated with low birth weight.  相似文献   
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In this study, the authors examined the concentrations and mineralogical analyses of asbestos, and investigated mesothelioma risk in southeastern Anatolia, Turkey. They used a gravimetric dust sampler to collect samples from 2 villages and 2 asbestos mines (1 active). Samples were then evaluated by an X-ray diffractometer and an electron microscope. The authors found high concentrations of asbestos in an active mine (4.9 fibers[f]/cm3) and at a house that was plastered with asbestos (1.24 f/cm3) and had a very active population. They found a low concentration (0.0042 f/cm3) in indoor measurements taken in Armutova village, and an even lower concentration (0.000081 f/cm3) in the inactive mine environment. Outdoor measurements included a low concentration of 0.007 f/cm3 in the village environment, and a high concentration of 1.17 f/cm3 on the mine road during the passing of a sheep herd. The people in the region are continuously exposed to asbestos during normal activities. This cumulative exposure to asbestos carries sufficient risks for mesothelioma development.  相似文献   
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The purpose of this study was to determine the discriminative factors between rheumatoid arthritis (RA) patients with and without major depression (MD). We assessed subjective sleep quality, pain, and cell-mediated immune functions in RA patients with (n = 20) and without (n = 20) MD by using Pittsburgh Sleep Quality Index (PSQI), visual analogue scale (VAS), and fluorescein isothiocyanat (FITC) labeled CD3, CD4, CD8, CDI9, CD45, CD56, and HLADR T monoclonal antibodies by flow cytometry. We found that the RA patients with MD had significantly higher pain level, poorer sleep equality, higher HDRS points, and higher HLADR T cell level than those without MD; and that these variables are discriminant factors between patient groups. These findings suggest that the RA patients with MD may be differentiated from those without MD by using VAS, PSQI, and HLADR levels; that these variables correctly classify the depressed and non depressed groups up to an accuracy level of 96.8%.  相似文献   
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The objective of this study was to determine the acute effect of trimetazidine (TMZ) on the pre-fatigue, fatigue and post-fatigue contractile characteristics and tension-frequency relationships of isolated rat diaphragm muscle. Muscle strips were taken from the ventral-costal aspects of the diaphragm muscle of rats killed by decapitation. The muscle strips were suspended in organ baths containing Krebs solution, with a gas mixture of 95% O2 and 5% CO2 at 37 degrees C and pH 7.35-7.45. After determining the thermoregulation and optimum muscle length the muscles were subjected to direct supramaximal stimulation with 0.05 Hz frequency square pulses for periods of 0.5 msec to obtain control values. After adding 5 x 10(-6) and 5 x 10(-5) M trimetazidine solution to the respective bath media, the contractile parameters of the muscles were recorded. The contractile parameters were also recorded for both the trimetazidine and trimetazidine-free media after application of the high frequency fatigue protocols. Later, the tension-frequency relationship was determined by applying stimulating pulses of 10, 20, 50 and 100 Hz to the muscle strips. Whilst the twitch tension obtained from the 5 x 10(-6) and 5 x 10(-5) M trimetazidine media showed numerical increases compared to that of the controls, these were not statistically significant (p>0.05). The contraction time exhibited a dose dependent increase (p<0.001), whilst the contraction and relaxation rates did not differ significantly. The isometric contraction forces obtained with the different stimulating frequencies showed a significant increase in the tetanic contraction only at 100 Hz (p<0.05). A comparison of the pre- and post-fatigue twitch tensions in the trimetazidine media showed the post- fatigue twitch tensions to be significantly higher than those of the pre-fatigue contraction forces (p<0.05). In the 5 x 10(-6) and 5 x 10(-5) M trimetazidine media the increases in the post-fatigue contraction force were 22 and 30%, respectively. These results demonstrated that in isolated rat diaphragm muscle, TMZ significantly limited the mechanical performance decrease during fatigue. It is our opinion that trimetazidine contributed to the observed fatigue tolerance by eliminating the factors of fatigue, due to preservation of intracellular calcium homeostasis, provision of the ATP energy levels needed by ATPase dependent pumps and especially by keeping the intracellular pH within certain limits.  相似文献   
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Tuberculosis is still an important health problem in developing countries. A screening program was conducted upon learning that one of the teachers of a primary school in Ankara was diagnosed to have active pulmonary tuberculosis. A total of 341 students in the same building with the index case were screened for tuberculosis. There were 109 students with positive tuberculin test reaction. A higher ratio of tuberculin test positivity among the students of the teacher with active tuberculosis versus students vaccinated with BCG one year previously according to the routine vaccination program was determined. Isoniazid prophylaxis was given to the students with positive tuberculin test. The study shows the importance of an urgent work-up of index cases and their environment to prevent the spread of tuberculosis.  相似文献   
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