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91.
92.
BACKGROUND: Glomerular filtration rate (GFR) in humans and animals might be determined with precision by measuring the clearance of an ideal marker, such as inulin. However, the use of inutest, an inulin analog, is limited by its cost and accessibility. The present study tested whether low calorie commercial sugar (LC sugar) can be used to measure GFR during normal and renal dysfunction. METHODS: Two groups of 6 male Wistar rats weighing 300 to 350 g were included. One group was treated with a daily dose of cyclosporine (CsA) 30 mg/kg subcutaneously for 7 days and the other group was formed by nontreated control rats. In one half of each group, GFR was evaluated by using inutest and in the other half by using LC sugar. GFR was also evaluated by using a wide LC sugar plasma concentration range in an additional group. RESULTS: In nontreated rats, the mean GFR evaluated with LC sugar was 2.2 +/- 0.1 mL/min. This value is equal to that obtained with inutest: 2.3 +/- 0.1 mL/min. CsA administration produced a significant reduction of renal blood flow and renal function. The GFR reduction induced by CsA was similarly determined by both LC sugar and inutest to be at 1.0 +/- 0.2 and 1.1 +/- 0.2 mL/min (P= NS), respectively. In addition, GFR did not change when LC sugar plasma concentration gradually increased. CONCLUSION: Our results show that in both normal and pathophysiologic conditions, LC sugar is a good marker of GFR similar to the gold standard inutest. 相似文献
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94.
Sudden cardiac death is an elusive process that claims a significant number of lives annually in the United States. It is often associated with increased mortality within the first year after myocardial infarction, with the highest frequency occurring among patients with left ventricular dysfunction. Therefore, increasing survival rates in patients with a history of both disorders is an important goal of therapy. Recent trials suggested that an implantable cardioverter-defibrillator (ICD) in these patients may be superior to medical intervention in reducing the high mortality rate. Four major trials measured the benefits of an ICD for patients at risk for life-threatening ventricular arrhythmias. We assessed whether patients in these trials received adequate drug therapy as directed by American College of Cardiology-American Heart Association guidelines. One aim was to determine if medicated patients who served as controls in the trials were fairly represented. Furthermore, the need for improved overall guideline adherence was apparent. 相似文献
95.
目的探讨在老年2型糖尿病合并缺血性心脏病患者中尿微量蛋白在加重缺血性心脏病进展方面的作用。方法将66例老年2型糖尿病合并缺血性心脏病患者按24h尿微量蛋白排泄量分为:尿微量蛋白正常组及尿微量蛋白阳性组,分别对血脂、空腹血糖、血清胰岛素、胰岛素敏感指数、纤维蛋白原、颈动脉内-中膜厚度、颈总动脉粥样硬化等级积分、硬化斑块指数、心脏彩超室间隔厚度及射血分数等加重缺血性心脏病进展等指标进行比较分析。结果66例老年2型糖尿病合并缺血性心脏病患者尿微量蛋白阳性组高密度脂蛋白、载脂蛋白A、胰岛素敏感指数、年龄、纤维蛋白原、硬化斑块指数、颈总动脉粥样硬化等级积分、室间隔厚度及射血分数显著高于尿微量蛋白阴性组(P<0.05,P<0.01)。结论尿微量蛋白的出现能够加速糖尿病合并缺血性心脏病的发展进程,它的出现预示着缺血性心脏病的预后不良。 相似文献
96.
NJ Hoogenraad JD Mitchell NA Don TM Sutherland AC Mc Leay 《Archives of disease in childhood》1980,55(4):292-295
The activity of urea cycle enzymes was assayed in duodenal biopsy specimens obtained from a female infant who presented with neonatal hyperammonaemia. All enzyme levels were normal except N-acetyl glutamate-dependent carbamyl phosphate synthetase 1 (CPS1) which was half the mean activity in normal control specimens. A similar deficiency of CPS1 was also shown in duodenal specimens from the patient's mother who became slightly symptomatic after relatively high protein meals and during pregnancy, and had spontaneously modified her diet to one with protein restriction. The patient is growing normally on a dietary regimen similar to that spontaneously adopted by her mother. Urea cycle enzyme activity in the duodenal biopsy material from the controls was similar to that found in the normal human liver and appears to have distinct advantages as a means of assaying for urea cycle defects in patients with hyperammonaemia and their relatives. 相似文献
97.
目的 评估虚拟模拟器UroMentorTM在输尿管镜培训中的应用价值. 方法 30名泌尿外科医师按单独完成输尿管镜例数< 20例和≥20例分成2组,分别为18名及12名.应用左输尿管下段取石模拟操作进行初评,包括:总操作时间、输尿管插管时间、损伤致出血点的数目、尝试插管次数以及综合总体评分(GRS),连续训练48 h后复评并与初评比较. 结果 经过模拟器训练后所有受试者总操作时间明显缩短[( 333±32)s及(228±18)s,P=0.001],GRS评分明显改善(24.4±2.1及28.1±1.2,P=0.010).少(无)经验组和有经验组初评总操作时间[(405±40)s及(262±22)s,P=0.014]、复评总操作时间[(276±12)s及(179±9)s,P=0.000]及初评GRS评分(19.6±2.5及29.2±1.3,P=0.009)、复评GRS评分(25.0±1.1及31.2±0.7,P=0.002)差异均有统计学意义.独立完成的输尿管镜例数与GRS评分相关(初评r=0.705,复评r=0.756). 结论虚拟模拟器URO MentorTM可以成为输尿管镜技能培训及评估的有效工具. 相似文献
98.
目的:构建含有双启动子的shRNA真核表达载体.方法:通过PCR分别扩增带有BamH Ⅰ、EcoR Ⅰ酶切位点的人U6启动子序列(U6-B/E)和带有Bgl Ⅱ、HindⅢ酶切位点的人U6启动子序列(U6-B/H),用BamH Ⅰ与EcoRⅠ双酶切pcDNA3.1(+)与PCR产物U6-B/E后进行连接,重组质粒命名为psPRO.再用BglⅡ与HindⅢ双酶切psPRO与PCR产物U6-B/H后进行连接,构建含有双启动子的shRNA真核表达载体.结果:酶切鉴定以及DNA测序结果显示载体构建成功.结论:构建双启动子的shRNA真核表达载体,使其在细胞中表达2个不同的siRNA,不仅筛选方便,而且可以通过建立这种模式化工具载体,为今后RNA干扰实验研究的开展和深入提供手段. 相似文献
99.
目的评价替比夫定治疗HBeAg阳性慢性乙型肝炎48周的疗效和安全性。方法将HBeAg阳性慢性乙型肝炎患者104例分为两组,治疗组53例,对照组51例。治疗组口服替比夫定600mg,每日1次,疗程48周;对照组口服阿德福韦酯10mg,每日1次,疗程48周。观察两组治疗12、24、36、48周时的HBV-DNA阴转率、ALT复常率、HBeAg阴转率、HBeAg血清转换率及治疗过程中的不良反应。结果治疗12、24、36、48周时,两组HBV-DNA阴转率、ALT复常率相比较差异有统计学意义(P﹤0.05),而HBeAg阴转率及HBeAg血清转换率相比较差异无统计学意义(P﹥0.05)。治疗组在服药期间未出现严重不良反应。结论替比夫定治疗HBeAg阳性慢性乙型肝炎是有效的和安全的。 相似文献
100.
目的 建立干槽症的小鼠模型.方法 取10只小鼠,随机分为实验组和对照组.每只小鼠腹腔注射1.5%戊巴比妥麻醉后,拔除上颌中切牙.实验组拔牙窝行肾上腺素止血,植入金黄色葡萄球菌标准菌种,对照组拔除上颌中切牙后无特殊处理.4天后观察两组拔牙窝情况并处死小鼠,取上颌骨进行组织切片、HE染色,观察两组拔牙窝的结构变化.结果 拔牙4天后,实验组拔牙窝见大量脓性分泌物,周围黏膜红肿,对照组拔牙窝粘膜呈粉红色,创口较拔牙后明显缩小,无明显分泌物.观察组织学HE染色切片发现,实验组拔牙窝可见大量炎性细胞及少量破骨细胞,对照组的拔牙窝内有新生结缔组织形成.结论 使用肾上腺素和金黄色葡萄球菌标准菌种可以成功地建立小鼠切牙拔牙窝的干槽症模型. 相似文献