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991.
聚合酶链反应和噬菌体裂解试验监测鼠疫菌的应用比较研究 总被引:2,自引:1,他引:1
应用聚合酶链反应 (PL-PCR)技术和噬菌体裂解试验同时对 80株鼠疫菌 ,1株假结核株、 1株大肠杆菌埃希氏菌进行检测并作比较。结果显示经噬菌体裂解试验 82株菌均在 18~ 2 0 h显示出噬菌斑 ,而其中 2株聚合酶链反应为阴性 ,另 80株全部为鼠疫菌特异性扩增带 ,比较清晰、典型、稳定 ,它有助于鼠疫菌快速特异诊断 相似文献
992.
《中国矫形外科杂志》被引分析研究 总被引:5,自引:1,他引:4
目的:分析《中国矫形外科杂志》被引情况,从文献引证角度了解该刊学术水平和期刊质量。方法:利用清华大学同方光盘股份有限公司研制开发的中国医院知识仓库期刊全文数据库中的数据,用定量分析的方法,对《中国矫形外科杂志》被引情况进行统计、分析和研究。结果:总被引2039篇次,被引频次逐年上升。2002年自引率1839%,单篇平均被引1.2次,影响因子0.293。结论:《中国矫形外科杂志》已形成自己的学术风格和专业特点,具有较高的被引率,是我国骨科领域的精品期刊之一。 相似文献
993.
994.
Purpose. The inhibitory effects of omeprazole on diazepam metabolism in vitro and in vivo are compared in the rat.
Methods. 3-hydroxylation and N-demethylation of diazepam was investigated in the presence of a range of omeprazole concentrations (2-500µM) in hepatic microsomes and hepatocytes. Zero order infusions together with matched bolus doses of omeprazole were used to achieve a range of steady state plasma concentrations (10-50mg/ L) and to study the diazepam-omeprazole interaction in vivo.
Results. The 3-hydroxlation pathway was more prone to inhibition (KIs 108 ± 30 and 28 ± 11 µM in microsomes and hepatocytes, respectively) than the demethylation pathway (KIs of 226 ± 76 and 59 ± 27 µM in microsomes and hepatocytes, respectively). In both in vitro systems, the mechanism of inhibition was competitive with Km/KI ratios larger than 1 for the 3HDZ pathway and smaller than 1 for the NDZ pathway. There was an omeprazole concentration dependent decrease in diazepam clearance in vivo which could be modelled using a simple inhibition equation with a KI of 57µM (19.8mg/L). In contrast there was no statistically significant change in the steady state volume of distribution for diazepam in the presence of omeprazole.
Conclusions. The in vivo KI for the omeprazole: diazepam inhibition interaction shows closer agreement with the KI values obtained in hepatocytes than with those observed in microsomes. 相似文献
995.
用十二烷基硫酸钠或十二烷基磺酸钠与亚硫酸的混合液浸泡玉米,能有效地降低玉米淀粉中的蛋白质含量,较单独用亚硫酸浸泡,所得玉米淀粉的蛋白质含量可分别降低40%和35%。 相似文献
996.
Clinical symptoms and findings in cranial computed tomography (CT) were evaluated in 326 patients with intracerebral hemorrhage (ICH). Localizations of ICH were the lobes (n = 254), the basal ganglia (n = 46), the pons and brain stem (n = 13) and the cerebellum (n = 8). Multiple hematomas were present in nine patients. An initial coma (n = 225) was most frequent in ICH of the pons (n = 7), cerebellum (n = 6), and the frontal (n = 71) and temporal (n = 66) lobes. Epileptic seizures (n = 70) were most common in hematomas of the frontal (n = 24), temporal (n = 19) and parietal (n = 12) lobes and the basal ganglia (n = 6). A history of hypertension was given in 140 patients; 119 of these had an ICH with a size of ≥3 cm. Mortality (n = 162) was high with ICH in the pons and brain stem (10 out of 13), in the frontal (54 out of 98) and parietal (32 out of 58) lobes and the basal ganglia (n = 23). A size of the ICH of 3 cm or more in cranial CT and an associated ventricular hemorrhage were associated with a bad outcome. An initial disturbance of consciousness was the only reliable clinical predictor of outcome (chi-square, p < 0.001). Katamnestic evaluation of 66 of the 164 survivors after 5.2 years revealed seizures in 20 patients and mild neurological deficits in 41. Another 14 patients were partially, and nine totally dependent Nineteen patients had died in between; there was only one death attributable to another ICH. 相似文献
997.
从医务人员的证据意识谈举证责任倒置 总被引:2,自引:0,他引:2
文章从剖宫产术后伴发腰腿痛病例分析入手,认为举证责任倒置就在我们诊疗工作中,就在我们协调医患关系的过程中。因此需要在临床实践中去感悟举证责任置的深刻含义,从而树立证据意识,做好证据的收集与保存工作,一旦发生诉讼有证为据,并由此提出了“医学证据学”的构想,而医学证据的特点有待进一步深入研究。 相似文献
998.
本文研究了15个水稻品种的抗性遗传,品种国眉占的抗性受一对隐性基因控制,BG367-4受两对隐性基因控制;三桂占1、Suweon294、KAU1727、IR13539-100-2-2-2-3、IR749-5-2-1-1以及IR13240-108-2-2-3均受一对显性基因控制;IR25586-108-1-2-2-2受两对显性基因控制;三黄占2、三叶占1、铁六选;新惠占1、GENG77-4以及IR13427-40-2-3-3都受一对显性基因和一对隐性基因因控制,同时对12个具有不同抗性水平的水稻品种苗期的抗菌表现进行了遗传型稳定性分析。结果表明,不同品种的抗性稳定性有明显差异,TN1是极稳定的高感品种TG367-4、25586-108-1-2-2-2以及Mudgo是非常稳定的高抗;一叶占1、三桂占1和铁六这三个抗级品种的抗虫也较稳定;;而抗级品种国眉占、三黄占2、Suweon294和抗品种包选2、辐包矫21的抗虫性不稳定。 相似文献
999.
A morphometric analysis of the developing organ of Corti and its component hair cells was carried out in an age-graded series of Syrian golden hamsters with the aid of scanning electron microscopy. The purpose was to establish a quantitative framework that would provide insight into the rules and principles by which the mammalian cochlea attains its adult proportions. This study examined postnatal development at two day intervals from birth to 22 days after birth. Our analysis included measures of cochlear length and hair cell numbers as well as measures of hair cell sizes in each of five sectors along the cochlear spiral. Our results demonstrate several principles of cochlear development: (1) The full two and one-fourths turns seen in the adult cochlea are already present at birth, but the cochlea continues to elongate for the next 10–12 days. (2) Development of hair cells in the apex generally lags behind that in the base. Whereas the stereocilia and apical margins of hair cells are clearly defined in the basal turn, they become well defined in the apex only postnatally. (3) Growth in cochlear length occurs mainly by increases in cell size rather than in cell numbers; although hair cells do increase in numbers during the first 4 days of cochlear growth, this increase involves addition of hair cells only to preexisting regions of the cochlear apex. Moreover, the full complement of hair cells is established 6 days before the full size of the cochlea is attained; in contrast, hair cell growth occurs at all positions along the cochlear spiral and spans the entire period of cochlear elongation. (4) The period of hair cell growth exceeds the period of organ of Corti growth and appears to be possible by decreases in intercellular spacing, primarily in the apical region of the cochlea; inner and outer hair cell growth was complete between 16 and 18 days after birth. (5) Inner and outer hair cell neighbors remain virtually constant at different ages indicating that the spatial relationships between the two hair cell populations is preserved as the cochlea grows. (6) Comparison with previous developmental studies of auditory function in the hamster reveals that the age of 16 days after birth, when hair cells attain their mature sizes, coincides with the onset of brainstem auditory evoked responses. Growth of hair cell somas alone, however, cannot explain either the subsequent maturation of evoked potential thresholds or changes in frequency representation in the developing cochlea. © Wiley-Liss, Inc. 相似文献