全文获取类型
收费全文 | 12034篇 |
免费 | 738篇 |
国内免费 | 85篇 |
专业分类
耳鼻咽喉 | 111篇 |
儿科学 | 358篇 |
妇产科学 | 230篇 |
基础医学 | 1295篇 |
口腔科学 | 539篇 |
临床医学 | 1022篇 |
内科学 | 2689篇 |
皮肤病学 | 230篇 |
神经病学 | 698篇 |
特种医学 | 450篇 |
外国民族医学 | 4篇 |
外科学 | 1820篇 |
综合类 | 528篇 |
一般理论 | 10篇 |
预防医学 | 764篇 |
眼科学 | 318篇 |
药学 | 1016篇 |
中国医学 | 70篇 |
肿瘤学 | 705篇 |
出版年
2023年 | 151篇 |
2022年 | 443篇 |
2021年 | 794篇 |
2020年 | 411篇 |
2019年 | 487篇 |
2018年 | 615篇 |
2017年 | 340篇 |
2016年 | 391篇 |
2015年 | 399篇 |
2014年 | 528篇 |
2013年 | 654篇 |
2012年 | 924篇 |
2011年 | 922篇 |
2010年 | 471篇 |
2009年 | 413篇 |
2008年 | 604篇 |
2007年 | 617篇 |
2006年 | 541篇 |
2005年 | 532篇 |
2004年 | 535篇 |
2003年 | 414篇 |
2002年 | 428篇 |
2001年 | 88篇 |
2000年 | 70篇 |
1999年 | 72篇 |
1998年 | 116篇 |
1997年 | 87篇 |
1996年 | 72篇 |
1995年 | 75篇 |
1994年 | 55篇 |
1993年 | 42篇 |
1992年 | 21篇 |
1991年 | 42篇 |
1990年 | 43篇 |
1989年 | 53篇 |
1988年 | 35篇 |
1987年 | 33篇 |
1986年 | 43篇 |
1985年 | 30篇 |
1984年 | 26篇 |
1983年 | 29篇 |
1982年 | 19篇 |
1981年 | 24篇 |
1980年 | 28篇 |
1979年 | 15篇 |
1978年 | 11篇 |
1977年 | 16篇 |
1976年 | 13篇 |
1975年 | 14篇 |
1974年 | 10篇 |
排序方式: 共有10000条查询结果,搜索用时 187 毫秒
31.
Serum ionic fluoride levels in haemodialysis and continuous ambulatory peritoneal dialysis patients 总被引:1,自引:1,他引:0
al-Wakeel JS; Mitwalli AH; Huraib S; al-Mohaya S; Abu-Aisha H; Chaudhary AR; al-Majed SA; Memon N 《Nephrology, dialysis, transplantation》1997,12(7):1420-1424
High serum fluoride (F-) in patients with chronic renal failure (CRF) and
end-stage renal disease (ESRD) is associated with risk of renal
osteodystrophy and other bone changes. This study was done to determine F-
in normal healthy controls and patients with ESRD on haemodialysis (HD) or
peritoneal dialysis (PD). Seventeen healthy controls (12 males, 5 females)
and 39 ESRD patients on dialysis (17 males, 22 females) were recruited in
the study in a community with 47.4 +/- 3.28 microM/l (range 44-51 microM/l)
of F- content in drinking water. Control subjects showed a mean serum F-
concentration of 1.08 +/- 0.350 microM/l. Males in control group showed
slightly higher F- levels (1.15 +/- 0.334, range 0.55-1.9 microM/l) than
females (0.92 +/- 0.370, range 0.6-1.5 microM/l). Mean serum F-
concentration did not correlate significantly with age and sex among
control subjects, whereas such correlation was observed in patients with
ESRD on dialysis. Mean serum F- concentration was significantly higher in
patients on dialysis (2.67 +/- 1.09, range 0.8-5.2 microM/l) than normal
controls. When grouped according to sex, the mean serum F- concentration in
males (3.05 +/- 1.04, range 1.8-5.2 microM/l) was significantly higher than
females (2.38 +/- 1.08, range 0.8-5.2 microM/l). When patients were grouped
according to age, it was observed that F- concentration was significantly
higher in patients with age groups 21-70 (2.86 +/- 1.05) than those with
age group 13-20 years (1.42 +/- 0.531). Thus F- concentration correlated
with age and sex, being higher in males and above 20 years. Despite
appreciable clearance of F- (39-90%) across the peritoneum, patients on
CAPD showed higher serum F- concentration than those on HD (3.1 +/- 1.97 vs
2.5 +/- 1.137 microM/l). Of the total 39 patients on dialysis 39% had their
serum F- concentration above 3.0 microM/l, posing the risk of renal
osteodystrophy.
相似文献
32.
33.
The evolution of a biodegradable membrane for use in urological surgery. A summary of 109 in vivo experiments 总被引:3,自引:0,他引:3
R Scott R Mohammed S D Gorham D A French M J Monsour A Shivas T Hyland 《British journal of urology》1988,62(1):26-31
The evolution of a collagen/vicryl composite membrane designed as a prosthetic material for use in urinary tract surgery is described. The early experiments in which collagen film alone was used to repair experimental ureterotomies are reviewed together with our first experiments with the collagen/vicryl prosthesis in the repair of partial nephrectomies and of full thickness defects created in the urinary bladder of experimental rabbits. These early results led to the preparation of a composite using a more highly purified collagen and employing a method of sterilisation (gamma irradiation) which would be acceptable for regular use in medical products. The results of a further series of partial nephrectomy and full thickness bladder repairs show that irradiation does not compromise the efficacy of the collagen/vicryl composite in vivo. 相似文献
34.
35.
B G Henriksson S S?derstr?m A J Gower T Ebendal B Winblad A H Mohammed 《Behavioural brain research》1992,48(1):15-20
Brain nerve growth factor (NGF) was determined in two groups of aged rats: 'good' and 'poor' performers. The animals were selected out of a population of 40 aged rats (26-28 months old) trained in a spatial learning task. Animals performing well in the test had significantly higher NGF in the hippocampus when compared to 'poor' performers. No differences in the levels of NGF were found in the cortex, septum and cerebellum. The results implicate hippocampal NGF in cognitive functioning of aged rats, and suggests that the forebrain cholinergic neuronal atrophy which has been observed in cognitively impaired aged rats may be due to reduced availability of target-derived NGF. 相似文献
36.
Sendhil K Balasubramanian Ravindranath Tiruvoipati Mohammed Amin Kanakkande K Aabideen Giles J Peek Andrew W Sosnowski Richard K Firmin 《Journal of cardiothoracic surgery》2007,2(1):4-9
Background
Veno-arterial extracorporeal membrane oxygenation (ECMO) is a common modality of circulatory assist device used in children. We assessed the outcome of children who had ECMO following repair of congenital cardiac defects (CCD) and identified the risk factors associated with hospital mortality. 相似文献37.
Propofol versus traditional sedative agents for gastrointestinal endoscopy: a meta-analysis. 总被引:6,自引:0,他引:6
Mohammed A Qadeer John J Vargo Farah Khandwala Rocio Lopez Gregory Zuccaro 《Clinical gastroenterology and hepatology》2005,3(11):1049-1056
BACKGROUND & AIMS: Even though propofol has better recovery profile than traditional agents, its use is limited because of the perception of increased complication rates. Because an adequately powered trial comparing risk of propofol with traditional agents is lacking, we performed a meta-analysis of the current literature. METHODS: We searched Medline (1966-October 2004), EMBASE (1980-October 2004), and Cochrane controlled trials registry. The following 4 cardiopulmonary complications were assessed: hypoxia, hypotension, arrhythmias, and apnea. Procedures were divided into 3 groups: esophagogastroduodenoscopy group, colonoscopy group, and endoscopic retrograde cholangiopancreatography/endoscopic ultrasonography group. Pooled odds ratios for complications were calculated for all the procedures combined and then separately for the 3 groups. Random effects models were used for 2-proportion comparisons. RESULTS: Of the 90 citations identified, 12 original studies qualified for this meta-analysis and included 1161 patients. Of these, 634 received propofol, and 527 received midazolam, meperidine, and/or fentanyl. Most of the included studies were randomized trials of moderate quality and nonsignificant heterogeneity (Cochran Q = 4.81, P = .90). Compared with traditional sedative agents, the pooled odds ratio with the use of propofol for developing hypoxia or hypotension for all the procedures combined was 0.74 (95% confidence interval [CI], 0.44-1.24); for EGD, 0.85 (95% CI, 0.33-2.17); for colonoscopy, 0.4 (95% CI, 0.2-0.79); and for ERCP/EUS, 1.07 (95% CI, 0.38-3.01). CONCLUSIONS: Propofol sedation during colonoscopy appears to have lower odds of cardiopulmonary complications compared with traditional agents, but for other procedures, the risk of complications is similar. 相似文献
38.
Mohammed AL-JUMAILY Alexei KOZLENKOV Ilana MECHALY Agnes FICHARD Valerie MATHA Frederique SCAMPS Jean VALMIER Patrick CARROLL 《中国神经科学杂志》2007,(5)
目的在背根神经节(dorsal root ganglion,DRG)中等大小感觉神经元中可以观察到钙激活氯离子流(I_(Cl(Ca)))。在坐骨神经损伤模型中,在大多数大中神经元上诱导出类似的氯离子流。本文旨在探讨引起这个离子流的分子基础。方法使用常规的定量RT-PCR方法检测在DRG中三个基因家族的表达,这三个基因家族都具有诱导I_(Cl(Ca))的特点。结果在成年小鼠的DRG中,分别显示了在正常状态和坐骨神经损伤3天后CLCA,Bestrophin和Tweety基因家族成员的转录产物。结论mBestl和Tweety2可能在损伤诱导的DRG神经元I_(Cl(Ca))中发挥作用。 相似文献
39.
Focal liver lesions: characterization with triphasic spiral CT 总被引:15,自引:1,他引:14
40.
Valsamma Eapen Mona Essa Jakka Mohammed T Abou-Saleh 《Revue canadienne de psychiatrie》2003,48(6):402-407
OBJECTIVE: The prevalence of child psychiatric morbidity in the community is unknown in most developing countries, including those in the Arab region. METHOD: An epidemiologic study was carried out to estimate the prevalence of psychiatric morbidity and to determine the sociodemographic correlates in a sample of children in the community, aged 6 to 18 years, in A1 Ain, United Arab Emirates (UAE). RESULTS: We obtained a prevalence rate of 22.2% for overall morbidity, as classified in the DSM-1V, and 14.3% for those with significant dysfunction, with the most common diagnosis being mood disorders. Female sex, large family size, chronic life difficulties, family history of psychiatric disorder, and alcohol-related problems in a family member were significantly associated with DSM-IV diagnosis. CONCLUSION: Although the prevalence and symptomatology in this Middle East community are similar to those in Western studies, none of these children had received professional help, suggesting serious deficiencies in mental health care services in the country. 相似文献