全文获取类型
收费全文 | 37080篇 |
免费 | 2619篇 |
国内免费 | 161篇 |
专业分类
耳鼻咽喉 | 282篇 |
儿科学 | 1080篇 |
妇产科学 | 734篇 |
基础医学 | 4608篇 |
口腔科学 | 643篇 |
临床医学 | 3577篇 |
内科学 | 8332篇 |
皮肤病学 | 564篇 |
神经病学 | 3922篇 |
特种医学 | 1144篇 |
外国民族医学 | 1篇 |
外科学 | 5263篇 |
综合类 | 527篇 |
一般理论 | 30篇 |
预防医学 | 3047篇 |
眼科学 | 741篇 |
药学 | 2623篇 |
1篇 | |
中国医学 | 54篇 |
肿瘤学 | 2687篇 |
出版年
2023年 | 238篇 |
2022年 | 352篇 |
2021年 | 718篇 |
2020年 | 480篇 |
2019年 | 707篇 |
2018年 | 816篇 |
2017年 | 626篇 |
2016年 | 679篇 |
2015年 | 819篇 |
2014年 | 1163篇 |
2013年 | 1628篇 |
2012年 | 2428篇 |
2011年 | 2714篇 |
2010年 | 1504篇 |
2009年 | 1389篇 |
2008年 | 2285篇 |
2007年 | 2587篇 |
2006年 | 2453篇 |
2005年 | 2549篇 |
2004年 | 2294篇 |
2003年 | 2186篇 |
2002年 | 2020篇 |
2001年 | 340篇 |
2000年 | 261篇 |
1999年 | 391篇 |
1998年 | 451篇 |
1997年 | 338篇 |
1996年 | 344篇 |
1995年 | 281篇 |
1994年 | 243篇 |
1993年 | 272篇 |
1992年 | 230篇 |
1991年 | 218篇 |
1990年 | 181篇 |
1989年 | 160篇 |
1988年 | 171篇 |
1987年 | 152篇 |
1986年 | 117篇 |
1985年 | 177篇 |
1984年 | 246篇 |
1983年 | 206篇 |
1982年 | 242篇 |
1981年 | 248篇 |
1980年 | 240篇 |
1979年 | 118篇 |
1978年 | 132篇 |
1977年 | 127篇 |
1976年 | 115篇 |
1974年 | 92篇 |
1973年 | 76篇 |
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
111.
112.
Jane Avery Serene Manzar Ashtari Philip R Szeszko Sanjiv Kumra 《Revue canadienne de psychiatrie》2007,52(3):135-145
OBJECTIVES: To critically review and integrate, from a developmental perspective, recent magnetic resonance imaging (MRI) studies of 4 childhood psychiatric disorders: schizophrenia, bipolar disorder (BD), attention-deficit hyperactivity disorder (ADHD), and major depressive disorder (MDD). METHOD: We reviewed published reports in refereed journals. We briefly describe the major findings with respect to the brain morphometry, chemistry, and function of children with psychiatric disorders and synthesize the reports in a summary to update clinicians. RESULTS: Some cortical grey matter abnormalities associated with schizophrenia appear to predate the onset of frank psychosis and continue to advance after the onset of psychosis, at least in more severe cases. Pediatric BD is associated with abnormalities in a circuit, thought to be involved in mood regulation, that encompasses the amygdala, striatum, and ventral PFC. Frontostriatal abnormalities are reported consistently in ADHD, potentially reflecting abnormalities in the development of cognitive control. Children with MDD show prefrontal cortical alterations that may differ in familial and nonfamilial subtypes of MDD. CONCLUSIONS: Results from neuroimaging studies of childhood psychopathology reveal abnormalities in the developmental trajectories observed in healthy children. Although MRI has increased our understanding of the pathophysiology of these disorders, routine neuroimaging for children with severe emotional disturbances is not indicated for diagnostic purposes. 相似文献
113.
114.
Cefazolin plus ceftazidime versus imipenem/cilastatin monotherapy for treatment of CAPD peritonitis--a randomized controlled trial. 总被引:2,自引:0,他引:2
Chi-Bon Leung Cheuk-Chun Szeto Kai-Ming Chow Bonnie Ching-Ha Kwan Angela Yee-Moon Wang Siu-Fai Lui Philip Kam-Tao Li 《Peritoneal dialysis international》2004,24(5):440-446
BACKGROUND: Peritonitis is a serious complication of peritoneal dialysis (PD). We studied the efficacy of imipenem/cilastatin monotherapy in the treatment of PD-related peritonitis. METHODS: We performed an open-label, randomized control study comparing imipenem/cilastatin monotherapy (treatment group) versus cefazolin plus ceftazidime (control group) in the treatment of PD peritonitis. The result was further compared to a historic group treated with cefazolin plus netilmycin. Outcome measures were primary response rate at day 10 and complete cure rate. RESULTS: We enrolled 51 patients in the treatment group, 51 in the control group, and identified 96 in the historic group. The primary response rate to the assigned antibiotics was 49.0%, 51.0%, and 49.0% for the treatment, control, and historic groups, respectively (p = 0.97). The primary response rate allowing for change in antibiotic was 82.4%, 90.2%, and 82.3%, respectively, for the three groups (p = 0.41). The complete cure rate was 72.5%, 80.4%, and 82.3%, respectively (p = 0.60). Tenckhoff catheter removal was needed in 6 cases in the treatment group, 6 cases in the control group, and 13 cases in the historic group (p = 0.90). CONCLUSIONS: We concluded that monotherapy of imipenem/cilastatin has similar efficacy compared to the two standard regimens of cefazolin plus ceftazidime or netilmycin in the treatment of PD peritonitis. 相似文献
115.
116.
Peter A. Schneider Peter W. Abcarian Darren Y. Ogawa Jean R. Leduc Philip W. Wright 《Annals of vascular surgery》1997,11(6):574-580
p < 0.01). Cumulative combined primary patency at 1 year by life-table methods was 82 ± 10% in the staged group and 83 ± 9%
in the simultaneous group (p= 0.79). Mean follow-up was 13 ± 6 months. There is a role for balloon angioplasty and stent placement in operative revascularization
of ischemic limbs in selected patients: patency was similar to that produced with the staged approach while the length of
stay was shorter. Intraoperative balloon angioplasty is safe and effective and stents permit a measure of control in assuring
an optimal intraoperative postangioplasty result. 相似文献
117.
Anne Deans Philip Steer 《BJOG : an international journal of obstetrics and gynaecology》1994,101(12):1099-1099
118.
Hubert O Ballard Philip Bernard Joseph Qualls William Everson Lori A Shook 《Journal of investigative medicine》2007,55(6):299-305
Bronchopulmonary dysplasia (BPD) is a pulmonary disorder that causes significant morbidity and mortality in premature infants. BPD is pathologically characterized by inflammation, fibrosis, and mucosal necrosis, which leads to emphysematous coalescence of alveoli. We tested the hypothesis that azithromycin, a macrolide antibiotic, would decrease the severity of lung injury in an animal model of BPD. Sixty-three rat pups were randomly divided equally into control, hyperoxia, and hyperoxia plus azithromycin groups. The hyperoxia groups were exposed to > 95% oxygen from days of life 4 to 14. On day 14, the animals were processed for lung histology and tissue analysis. Lung morphology was assessed by mean linear intercept, a measure of alveolar size, with larger values corresponding to lungs that are more emphysematous. The degree of lung inflammation was assessed by quantifying interleukin-6 (IL-6) from lung homogenate. Fifty pups survived to day 14 (control = 21, hyperoxia = 11, hyperoxia + azithromycin = 18). Mortality was increased in the hyperoxia group versus the control group (p < .0001). Treatment with azithromycin improved survival in animals subjected to hyperoxia (p < .05). Azithromycin significantly decreased lung damage as determined by the mean linear intercept in the hyperoxia groups (p < .001). Finally, azithromycin-treated pups had lower levels of IL-6 in lung homogenate from the hyperoxia groups (p < .05). Azithromycin treatment resulted in improved survival, less emphysematous change, and decreased IL-6 levels in an animal model of BPD. 相似文献
119.
We have investigated the ontogeny of MHC class I, class II, CD45, and macrophage antigens in wholemounts of normal human fetal retina at 10–25 weeks gestation (WG) using monoclonal antibodies and immunogold histochemistry. MHC class I antigens were expressed on retinal vascular endothelial cells and provided a useful marker of vessel organization from 14–25 WG. Microglial cells expressed immunoreactivity to MHC class I, class II, and CD45 antigens from 10 WG (pre-vascularization) and macrophage S22 (Mac S22) antigen from 14 WG (post-vascularization), although none of the antigens tested were detected on neuronal or macroglial elements. Microglia expressing MHC, CD45, and macrophage antigens occurred in both ramified and rounded forms with no close correlation being observed between morphology and antigenicity. The numbers of immunoreactive cells labeled with each of the four markers increased steadily throughout gestation in all specimens studied. Equivalent numbers of microglia expressed MHC class I, class II, and CD45 antigens in retinae at similar gestational ages; however, our data indicate that microglia expressing Mac S22 antigen comprise approximately 40% or less of the population of MHC and CD45-immunoreactive cells during development. Topographical analyses suggest that MHC class I, class II, and CD45-positive microglia enter the retina from both the peripheral retinal margin and the optic disc from at least 10 WG; Mac S22-positive cells appear in association with the development of the retinal vasculature and enter the retina via the optic disc after 14 WG. © 1995 Wiley-Liss, Inc. 相似文献
120.
Philip Darbyshire 《Nursing inquiry》1995,2(4):198-202
Reclaiming 'Big Nurse': a feminist critique of Ken Kesey's portrayal of Nurse Ratched in One Flew Over the Cuckoo's Nest Nurse Ratched or 'Big Nurse' in Ken Kesey's counter-culture novel One Flew Over the Cuckoo's Nest is one of popular culture's most arresting and memorable images of the nurse. She is, however, deemed to be remarkable primarily for her malice and authoritarianism. This paper argues that such a purely realist reading fails to fully appreciate the significance of the character of Nurse Ratched. A feminist critique of the novel contends that die importance of 'Big Nurse' is less related to how realistic/unrealistic or good/bad she is as a nurse. Nurse Ratched is important because she exemplifies all diat traditional masculinity abhors in women, and particularly in strong women in positions of power and influence. This paper explores the stereotype of 'Big Nurse' and argues that Kesey's vision of her ultimate 'conquest' is not a progressive allegory of 'individual freedom', but a reactionary misogyny which would deny women any function other than that of sexual trophy. 相似文献