全文获取类型
收费全文 | 1686篇 |
免费 | 58篇 |
国内免费 | 14篇 |
专业分类
耳鼻咽喉 | 6篇 |
儿科学 | 131篇 |
妇产科学 | 16篇 |
基础医学 | 147篇 |
口腔科学 | 36篇 |
临床医学 | 215篇 |
内科学 | 374篇 |
皮肤病学 | 19篇 |
神经病学 | 96篇 |
特种医学 | 231篇 |
外科学 | 257篇 |
综合类 | 36篇 |
预防医学 | 74篇 |
眼科学 | 19篇 |
药学 | 47篇 |
1篇 | |
肿瘤学 | 53篇 |
出版年
2021年 | 11篇 |
2020年 | 13篇 |
2019年 | 18篇 |
2018年 | 18篇 |
2017年 | 12篇 |
2016年 | 12篇 |
2015年 | 25篇 |
2014年 | 27篇 |
2013年 | 33篇 |
2012年 | 35篇 |
2011年 | 40篇 |
2010年 | 50篇 |
2009年 | 56篇 |
2008年 | 53篇 |
2007年 | 39篇 |
2006年 | 42篇 |
2005年 | 49篇 |
2004年 | 48篇 |
2003年 | 45篇 |
2002年 | 49篇 |
2001年 | 50篇 |
2000年 | 39篇 |
1999年 | 47篇 |
1998年 | 102篇 |
1997年 | 89篇 |
1996年 | 103篇 |
1995年 | 62篇 |
1994年 | 58篇 |
1993年 | 46篇 |
1992年 | 35篇 |
1991年 | 35篇 |
1990年 | 32篇 |
1989年 | 43篇 |
1988年 | 38篇 |
1987年 | 45篇 |
1986年 | 29篇 |
1985年 | 36篇 |
1984年 | 24篇 |
1983年 | 23篇 |
1982年 | 17篇 |
1981年 | 19篇 |
1980年 | 11篇 |
1979年 | 6篇 |
1978年 | 7篇 |
1977年 | 11篇 |
1976年 | 14篇 |
1975年 | 9篇 |
1973年 | 6篇 |
1971年 | 8篇 |
1966年 | 6篇 |
排序方式: 共有1758条查询结果,搜索用时 15 毫秒
11.
The compartment syndrome is an extremely rare complication after varicose vein surgery. If the early symptoms are not recognized and a treatment is not performed immediately most patients lose sensomotory function. Three cases with compartment syndrome after varicose vein stripping were the reason to point out the anatomy and pathophysiology of this complication and to explain the surgical technique. 相似文献
12.
Screening for complement deficiency in bacterial meningitis 总被引:1,自引:0,他引:1
T Ernst PJ Späth C Aebi UB Schaad MG Bianchetti 《Acta paediatrica (Oslo, Norway : 1992)》1997,86(9):1009-1010
Seventy-seven children with bacterial meningitis were screened for complement deficiency. Both the classical and the alternate pathways were normal in 75 patients. Transiently reduced total haemolytic activity of the classical pathway was documented in a boy with meningococcal meningitis. Total haemolytic activity of both the classical and the alternate pathways were reduced in another patient with pneumococcal meningitis: individual complement components determination indicated predominant activation of the alternate pathway. 相似文献
13.
14.
15.
16.
The major burden of preterm birth is in the developing world, where most of the increasing death and morbidity is secondary to infectious diseases such as malaria, HIV, tuberculosis, bacterial vaginosis and intestinal parasites. In some developing countries, the growth of medical care has outstripped the growth of preventive public health, with an associated increase in iatrogenic preterm births. In developed countries, more than one-third of preterm births are medically indicated because of conditions such as fulminating pre-eclampsia or severe intrauterine growth restriction. Neither of these conditions is currently preventable. One in five preterm births is associated with multiple pregnancy, and these have been greatly increased by assisted reproduction techniques. The use of tocolytics has proved disappointing perhaps because inflammation rather than spontaneous uterine activity is increasingly recognised as the final common pathway. Inappropriate antibiotics used late in pregnancy are ineffective and may have adverse effects. Currently, the most promising interventions are public health related and include reducing the transmission of communicable diseases, improvements in the management of diabetes and reduction in harmful behaviours such as smoking and drug abuse. 相似文献
17.
In order to study the pattern of B cell involvement in acute nonlymphocytic leukemia (ANLL), multiple B lymphoid cell lines were established by Epstein-Barr virus transformation of peripheral blood mononuclear cells from two patients with the disease who were heterozygous for the X chromosome-linked glucose-6-phosphate dehydrogenase (G6PD). In one patient, the progenitor cells involved by the leukemia exhibited multipotent differentiative expression, whereas in the other patient the cells showed differentiative expression restricted to the granulocytic pathway. In the patient whose abnormal clone showed multipotent expression, the ratio of B-A G6PD in B lymphoid cell lines was skewed in the direction of type B (the enzyme characteristic of the leukemia clone) and significantly different from the 1:1 ratio expected. It is, therefore, likely that the neoplastic event occurred in a stem cell common to the lymphoid series as well as to the myeloid series. In contrast, evidence for B cell involvement was not detected in the patient whose ANLL progenitor cells exhibited restricted differentiative expression. These findings underscore the heterogeneity of ANLL. Clinically and morphologically similar malignancies in these two patients originated in progenitors with different patterns of stem cell differentiative expression. This difference may reflect differences in cause and pathogenesis. 相似文献
18.
Glial cell-derived neurotrophic factor upregulates the expression and activation of matrix metalloproteinase-9 in human pancreatic cancer 总被引:4,自引:0,他引:4
BACKGROUND: We have previously reported that the glial cell-derived neurotrophic factor (GDNF) promotes pancreatic cancer cell invasion in vitro. The purpose of this study was to determine whether GDNF regulates the expression and activation of matrix metalloproteinase-9 (MMP-9) in human pancreatic cancer cells. METHODS: We used human pancreatic cancer cell line MIA PaCa-2. The effect of GDNF on mRNA and protein expression was measured by Northern blot, Western blot and enzyme-linked immunosorbent assay. MMP proteolytic activity was detected by gelatin zymography. To determine which intracellular pathways were involved, we used the following inhibitors: tyrosine kinase inhibitor Genistein, MEK-1 inhibitor PD98059 and PI3-K inhibitor Wortmannin. RESULTS: GDNF increased MMP-9 mRNA and protein expression in MIA PaCa-2 cells in a dose-dependent manner. Treatment with GDNF enhanced gelatinolytic activity of the pro and active form of MMP-9. Inhibitor experiments showed that the expression and activity of pro MMP-9 was totally inhibited by Genistein and partially by Wortmannin, whereas PD98059 had no effect. All three compounds inhibited the activity of the active form of MMP-9. CONCLUSIONS: GDNF upregulates the expression and enzymatic activity of MMP-9 through different signaling pathways in MIA PaCa-2. These findings suggest that GDNF modulates MMP-9 expression and activation, and this may promote pancreatic cancer invasion. 相似文献
19.
Since death on the operating table is a relatively rare incident, it raises a number of special medicolegal questions that are discussed in this article. One of the major concerns for medical personnel is being accused of malpractice during treatment, as it is an obvious presumption on the part of laymen that death was directly related to the medical treatment as compared with other in-hospital deaths. Questions such as who is responsible for issues of informed consent and liability are discussed. Other important aspects such as communication with the bereaved, transparent chronological documentation of the death circumstances, questions regarding certification of death, questions arising from autopsy done to determine the reason of death, questions about malpractice, legal requirements concerning confidential medical communication and information about what must be sent to the professional indemnity insurance company are elucidated. There is also some special information presented for cases that involve the deaths of Jehovah's Witnesses. 相似文献
20.
Ventral wall hernias are common; despite this, there are no guidelines on the best surgical management. The aim of this study
was to examine the types of repair in use for abdominal wall hernias in the West of Scotland over a 3-month period. Data were
gathered on 120 patients. There were 60 incisional, 32 umbilical, and 28 epigastric hernias. The main indication for repair
was pain (78%), while 12 patients (10%), presented acutely with incarceration or strangulation. The most common method of
repair was sutured (55%), followed by mesh (29%) and Mayo repair (16%). There was no correlation between use of mesh and hernia
size or whether repair was for a recurrent hernia. Surgical practice varies widely in the repair of ventral wall hernias.
Clinical trials are required to establish the best method of repair for this common condition.
Electronic Publication 相似文献