全文获取类型
收费全文 | 70838篇 |
免费 | 4808篇 |
国内免费 | 134篇 |
专业分类
耳鼻咽喉 | 672篇 |
儿科学 | 2788篇 |
妇产科学 | 1905篇 |
基础医学 | 8959篇 |
口腔科学 | 909篇 |
临床医学 | 10191篇 |
内科学 | 12269篇 |
皮肤病学 | 1031篇 |
神经病学 | 6691篇 |
特种医学 | 1505篇 |
外科学 | 7139篇 |
综合类 | 885篇 |
一般理论 | 124篇 |
预防医学 | 9096篇 |
眼科学 | 1145篇 |
药学 | 4844篇 |
3篇 | |
中国医学 | 69篇 |
肿瘤学 | 5555篇 |
出版年
2023年 | 337篇 |
2022年 | 525篇 |
2021年 | 1231篇 |
2020年 | 827篇 |
2019年 | 1270篇 |
2018年 | 1445篇 |
2017年 | 1152篇 |
2016年 | 1270篇 |
2015年 | 1488篇 |
2014年 | 2059篇 |
2013年 | 3232篇 |
2012年 | 4666篇 |
2011年 | 5046篇 |
2010年 | 2751篇 |
2009年 | 2497篇 |
2008年 | 4461篇 |
2007年 | 4726篇 |
2006年 | 4599篇 |
2005年 | 4637篇 |
2004年 | 4425篇 |
2003年 | 4208篇 |
2002年 | 3820篇 |
2001年 | 926篇 |
2000年 | 841篇 |
1999年 | 876篇 |
1998年 | 868篇 |
1997年 | 727篇 |
1996年 | 626篇 |
1995年 | 621篇 |
1994年 | 538篇 |
1993年 | 469篇 |
1992年 | 632篇 |
1991年 | 558篇 |
1990年 | 550篇 |
1989年 | 535篇 |
1988年 | 520篇 |
1987年 | 480篇 |
1986年 | 457篇 |
1985年 | 491篇 |
1984年 | 439篇 |
1983年 | 378篇 |
1982年 | 358篇 |
1981年 | 327篇 |
1980年 | 272篇 |
1979年 | 329篇 |
1978年 | 283篇 |
1977年 | 174篇 |
1976年 | 173篇 |
1974年 | 187篇 |
1973年 | 164篇 |
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
81.
82.
The most common cause of illness in infancy and childhood is acute infection of the respiratory tract. Several recent studies have reported that life-threatening respiratory disease in infancy, such as pneumonia and bronchiolitis, is directly related to the smoking habits of parents. The effects of smoking are more hazardous to youngsters because babies and young children breathe more rapidly than adults. Because of this higher breathing rate, they inhale more air—and more pollution—in comparison to their total body weight. The harmful effects of cigarette smoking on infants and children and recommendations for specific interventions to minimize or eliminate this health hazard are discussed. 相似文献
83.
David Hirschwerk Christine C Ginocchio Maureen Bythrow Susan Condon 《Infection control and hospital epidemiology》2006,27(3):315-317
We cared for a patient with methicillin-resistant Staphylococcus aureus bacteremia who experienced clinical failure with daptomycin. The failure was accompanied by progressive elevation of the daptomycin minimum inhibitory concentration during treatment. DNA fingerprinting confirmed that the minimum inhibitory concentration elevation occurred within the same strain of methicillin-resistant Staphylococcus aureus. This observation provides important new information to clinicians who adopt this promising drug for treatment of serious infections caused by methicillin-resistant Staphylococcus aureus. 相似文献
84.
85.
86.
87.
88.
M. E. Perry Y. Mustafa S. K. Wood M. I. D. Cawley D. C. Dumonde K. A. Brown 《Rheumatology international》1997,17(4):169-174
A morphological examination of synovial tissue from 25 patients with rheumatoid arthritis revealed that binucleated or multinucleated
plasma cells were present in all samples and absent in synovia obtained from 16 control patients. Plasma cells containing
two, three of four nuclei constitutet a mean 3% of the total plasma cell population. They were aways found amongst plasma
cell infiltrates and in close association with small blood vessels. Ultrastructural analysis found no evidence of cellular
membranes separating the individual nuclei in binucleated or multinucleated plasma cells, suggesting that the cells did not
arise from fusion. Some of these plasma cells had a diameter approaching 100 μm, and many were in intimate contact with macrophages.
The demonstration of a few cells with mitotic figures within the infiltrates suggests that the maintenance of plasma cell
numbers in rheumatoid synovium may depend, in part, upon their local proliferation.
Received: 25 August 1997 / Accepted: 2 October 1997 相似文献
89.
90.
Effects of Ethanol in an Experimental Model of Combined Traumatic Brain Injury and Hemorrhagic Shock 总被引:3,自引:2,他引:1
Brian J. Zink MD Susan A. Stern MD Xu Wang MD Carl C. Chudnofsky MD 《Academic emergency medicine》1998,5(1):9-17
Objectives: Given that clinical and laboratory studies suggest that ethanol and hemorrhagic shock (HS) potentiate traumatic brain injury (TBI), the authors studied the effects of ethanol in a model of combined TBI and HS.
Methods: A controlled porcine model of combined TBI and HS was evaluated for the effect of ethanol on survival time, hemodynamic function, and cerebral tissue perfusion. Anesthetized swine (17–24 kg) were instrumented, splenectomized, and subjected to fluid percussion TBI with concurrent 25-mL/kg graded hemorrhage over 30 minutes. Two groups were studied: control ( n = 11) and ethanol ( n = 11). Ethanol, 3.5 g/kg intragastric, was given 100 minutes prior to TBI/HS. Systemic and cerebral physiologic and metabolic parameters were monitored for 2 hours without resuscitation. Regional cerebral blood flow (rCBF) and renal blood flow were measured with dye-labeled microspheres. Data were analyzed with 2-sample t-test and repeated-measures ANOVA.
Results: Ethanol levels at the time of injury were 162 ± 68 mg/dL. Average TBI was 2.65 ± 0.35 atm. Survival time was significantly shorter in the ethanol group (60 ± 27 min vs 94 ± 28 min, p = 0.011). The ethanol group had significantly lower mean arterial pressure, cerebral perfusion pressure, and cerebral venous
O2 saturation in the postinjury period. Cerebral O2 extraction ratios and cerebral venous lactate levels were significantly higher in the ethanol group. A trend toward lower postinjury rCBF in all brain regions was observed in the ethanol group.
Conclusion: In this TBI/HS model, ethanol administration decreased survival time, impaired the hemodynamic response, and worsened measures of cerebral tissue perfusion. 相似文献
Methods: A controlled porcine model of combined TBI and HS was evaluated for the effect of ethanol on survival time, hemodynamic function, and cerebral tissue perfusion. Anesthetized swine (17–24 kg) were instrumented, splenectomized, and subjected to fluid percussion TBI with concurrent 25-mL/kg graded hemorrhage over 30 minutes. Two groups were studied: control ( n = 11) and ethanol ( n = 11). Ethanol, 3.5 g/kg intragastric, was given 100 minutes prior to TBI/HS. Systemic and cerebral physiologic and metabolic parameters were monitored for 2 hours without resuscitation. Regional cerebral blood flow (rCBF) and renal blood flow were measured with dye-labeled microspheres. Data were analyzed with 2-sample t-test and repeated-measures ANOVA.
Results: Ethanol levels at the time of injury were 162 ± 68 mg/dL. Average TBI was 2.65 ± 0.35 atm. Survival time was significantly shorter in the ethanol group (60 ± 27 min vs 94 ± 28 min, p = 0.011). The ethanol group had significantly lower mean arterial pressure, cerebral perfusion pressure, and cerebral venous
O
Conclusion: In this TBI/HS model, ethanol administration decreased survival time, impaired the hemodynamic response, and worsened measures of cerebral tissue perfusion. 相似文献