全文获取类型
收费全文 | 25343篇 |
免费 | 1232篇 |
国内免费 | 83篇 |
专业分类
耳鼻咽喉 | 335篇 |
儿科学 | 1428篇 |
妇产科学 | 607篇 |
基础医学 | 2778篇 |
口腔科学 | 576篇 |
临床医学 | 1441篇 |
内科学 | 5288篇 |
皮肤病学 | 803篇 |
神经病学 | 1517篇 |
特种医学 | 829篇 |
外科学 | 3247篇 |
综合类 | 1015篇 |
一般理论 | 15篇 |
预防医学 | 1248篇 |
眼科学 | 1392篇 |
药学 | 2251篇 |
1篇 | |
中国医学 | 179篇 |
肿瘤学 | 1708篇 |
出版年
2023年 | 171篇 |
2022年 | 428篇 |
2021年 | 873篇 |
2020年 | 431篇 |
2019年 | 553篇 |
2018年 | 710篇 |
2017年 | 489篇 |
2016年 | 612篇 |
2015年 | 592篇 |
2014年 | 931篇 |
2013年 | 1133篇 |
2012年 | 1587篇 |
2011年 | 1731篇 |
2010年 | 969篇 |
2009年 | 796篇 |
2008年 | 1212篇 |
2007年 | 1257篇 |
2006年 | 1264篇 |
2005年 | 1067篇 |
2004年 | 990篇 |
2003年 | 835篇 |
2002年 | 772篇 |
2001年 | 725篇 |
2000年 | 718篇 |
1999年 | 575篇 |
1998年 | 253篇 |
1997年 | 193篇 |
1996年 | 169篇 |
1995年 | 165篇 |
1994年 | 135篇 |
1993年 | 107篇 |
1992年 | 374篇 |
1991年 | 371篇 |
1990年 | 339篇 |
1989年 | 333篇 |
1988年 | 290篇 |
1987年 | 256篇 |
1986年 | 241篇 |
1985年 | 237篇 |
1984年 | 174篇 |
1983年 | 136篇 |
1981年 | 95篇 |
1979年 | 158篇 |
1978年 | 102篇 |
1977年 | 83篇 |
1975年 | 83篇 |
1974年 | 101篇 |
1973年 | 93篇 |
1972年 | 119篇 |
1970年 | 78篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
101.
Although Acinetobacter is usually a species of low virulence, it is becoming increasingly more important as a cause of hospital outbreaks, particularly on intensive care units. Antibiotic resistance can develop rapidly. This organism has not been reported to cause skin abscesses previously. We describe a case of a neonate who developed an Acinetobacter abscess on our neonatal intensive care unit. 相似文献
102.
H M Sharma C Dwivedi B C Satter K P Gudehithlu H Abou-Issa W Malarkey G A Tejwani 《Pharmacology, biochemistry, and behavior》1990,35(4):767-773
Maharishi-4 (M-4), an ayurvedic food supplement, was tested for anticarcinogenic and anticancer properties against 7,12-dimethylbenz(a)anthracene (DMBA)-induced mammary tumors in rats. The 6% M-4-supplemented diet protected DMBA-induced carcinogenesis by reducing both tumor incidence and multiplicity during initiation and promotion phases. The control animals who developed tumors when supplemented with M-4 diet for four weeks showed tumor regression in 60% of cases. There was no significant difference in the food intake or weight gain in rats who were on M-4-supplemented diet compared to control group. Possible mechanisms of action of M-4 are discussed. 相似文献
103.
An unusual retinal manifestation of arteriovenous communications is reported in a case showing a combination of Sturge-Weber and Kippel-Trenaunay syndromes. The arteriovenous communications are thought to be similar to those seen in the limbs in Parkes-Weber syndrome. This retinal finding indicates that the three syndromes are intricately related to each other and may be an incomplete manifestation of a single pathophysiologic entity which may be named neurocutaneous angiomatosis. 相似文献
104.
105.
106.
107.
Jane A. Kent-Braun PhD Khema R. Sharma MD Michael W. Weiner MD Robert G. Miller MD 《Muscle & nerve》1994,17(10):1162-1169
We investigated the role of metabolism in muscle fatigue during voluntary exercise in persons with mild multiple sclerosis (MS). Six MS and 8 healthy control subjects performed intermittent, progressive, isometric contractions of the ankle dorsiflexors, during which we measured maximum voluntary force (MVC), inorganic phosphate (Pi), phosphocreatine (PCr), and pH. During exercise. MVC fell sooner in MS, but by the end of exercise the relative decrease in MVC was similar in both groups. In contrast, at the end of exercise Pi/PCr increased to 1.86 ± 0.22 in controls but to only 0.66 ± 0.04 in MS (P < 0.01); likewise, pH was 6.75±0.04 in controls and unchanged (7.06 ± 0.04) in MS (P <0.01). The smaller metabolic change at the same relative exercise intensity suggests a failure of muscle activation that is present even in mild MS. Neurophsyiologic measures of activation indicated some central activation failure and no neuromuscular junction impairment in MS, and suggested that activation failure beyond the muscle membrane(excitation–contraction coupling) may be important in MS. We conclude that metabolic factors do not play a significant role in the development of muscle fatigue during voluntary exercise in mild MS. © 1994 John Wiley & Sons, Inc. 相似文献
108.
Kaufmann SJ; Sharif K; Sharma V; McVerry BA 《Human reproduction (Oxford, England)》1998,13(2):498-499
The patient was diagnosed in childhood as having severe congenital
neutropenia and had recurrent admissions with severe infections. In 1987,
prior to getting married, she was sterilized. She continued to require i.v.
antibiotics when she contracted a severe infection. On one occasion, she
was treated with growth colony stimulating factor (G- CSF). Her increased
neutrophil count was sustained following this treatment. In June 1993, she
wished to start a family and underwent in- vitro fertilization (IVF)
treatment. G-CSF was given prior to oocyte retrieval. She conceived on her
first cycle and an ultrasound scan revealed a singleton pregnancy.
Throughout the course of the pregnancy, her white cell count was monitored
closely and remained at <1.0x10(9)/l. The pregnancy progressed
uneventfully and at 37 weeks gestation she was admitted for G-CSF
injections. At 38 weeks she was delivered of a boy weighing 3350 g, by
elective Caesarean section. His white cell count was normal. This is the
first case of G-CSF being used before conception and during pregnancy in a
patient with congenital neutropenia. It shows that advances in cytokine
therapy and close interdisciplinary liaison can lead to a successful
outcome and help patients, who would otherwise remain childless, to achieve
a family.
相似文献
109.
110.
Kalpana Agarwal Anita Mukherjee Archana Sharma Ramesh Sharma Kuldip Raj Bhardwaj Soumitra Sen 《Environmental and molecular mutagenesis》1992,19(4):323-326
Fenfluramine, an amphetamine derivative used in the treatment of obesity, has been evaluated in vivo in the bone marrow cells of Swiss albino mice using two cytogenetic endpoints for assessing its genotoxic and clastogenic potentials. Concentrations of 0.75, 1.5, 3.0, and 5.0 mg/kg b.w. were administered orally for the study of sister chromatid exchange frequencies and chromosome aberrations (CA). SCE frequencies showed a positive dose response; 1.5 mg/kg being the minimum effective concentration. Fen caused a prolongation of cell cycle at all concentrations. Except for the minimum therapeutic dose (0.75 mg), all other doses (1.5, 3.0, and 5.0 mg) showed a significant increase in the percentage of damaged cells over that of the vehicle control. The degree of clastogenicity was directly proportional to the dosage used and inversely related with the duration of treatment. A gradual reduction of the clastogenic potential was observed after 12 and 24 hr of exposure, indicating that the maximum effect occurs at the middle or late synthetic phase of the cell cycle. This study, probably the first detailed screening of the drug for its genotoxicity, shows that Fen is moderately clastogenic and a DNA damaging agent in vivo. 相似文献