首页 | 官方网站   微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   3676篇
  免费   180篇
  国内免费   14篇
医药卫生   3870篇
  2022年   25篇
  2021年   75篇
  2020年   35篇
  2019年   65篇
  2018年   83篇
  2017年   51篇
  2016年   50篇
  2015年   57篇
  2014年   86篇
  2013年   136篇
  2012年   196篇
  2011年   195篇
  2010年   116篇
  2009年   92篇
  2008年   182篇
  2007年   174篇
  2006年   161篇
  2005年   176篇
  2004年   183篇
  2003年   179篇
  2002年   124篇
  2001年   114篇
  2000年   145篇
  1999年   136篇
  1998年   47篇
  1997年   36篇
  1996年   27篇
  1995年   25篇
  1994年   32篇
  1993年   24篇
  1992年   66篇
  1991年   75篇
  1990年   70篇
  1989年   64篇
  1988年   70篇
  1987年   68篇
  1986年   67篇
  1985年   69篇
  1984年   47篇
  1983年   42篇
  1982年   19篇
  1981年   20篇
  1980年   14篇
  1979年   32篇
  1978年   20篇
  1977年   9篇
  1976年   9篇
  1975年   15篇
  1973年   13篇
  1972年   8篇
排序方式: 共有3870条查询结果,搜索用时 31 毫秒
1.
Even if the relationships between nutrition and inflammatory bowel disease (IBD) remain underexplored, the current literature is providing, day by day, much more evidence on the effects of various diets in both prevention and treatment of such illnesses. Wrong dietary habits, together with other environmental factors such as pollution, breastfeeding, smoke, and/or antibiotics, are among the theoretical pathogenetic causes of IBD, whose multifactorial aetiology has been already confirmed. While some of these risk factors are potentially reversible, some others cannot be avoided, and efficient treatments become necessary to prevent IBD spread or recurrence. Furthermore, the drugs currently available for treatment of such disease provide low-to-no effect against the symptoms, making the illnesses still strongly disabling. Whether nutrition and specific diets will prove to effectively interrupt the course of IBD has still to be clarified and, in this sense, further research concerning the applications of such dietary interventions is still needed.  相似文献   
2.
3.
4.
5.
The implantation of chondrocytes, seeded on matrices such as hyaluronic acid or collagen membranes, is a method that is being widely used for the treatment of chondral defects. The aim of the present study was to evaluate the distribution, viability and phenotype expression of the cells seeded on a collagen membrane just at the time of the implantation. Twelve patients who were suffering from articular cartilage lesions were treated by the MACI® procedure. The residual part of each membrane was tested by colorimetric assay (MTT) and histochemical and ultrastructural analyses were carried out. In all of the samples a large number of viable cells, quite homogenously distributed, was detected. The cells expressed the markers of the differentiated hyaline chondrocytes. These data reassure in that the MACI procedure provides a suitable engineered tissue for cartilage repair, in line with the clinical evidences emerging in the literature.  相似文献   
6.
7.
Twenty-seven patients with metastatic adenocarcinoma of the prostate were treated with the new luteinizing hormone-releasing hormone analog, Zoladex (ICI 118,630) for up to ninety-eight weeks. Initially, treatment was randomized between Zoladex 250 micrograms and 500 micrograms self-injected subcutaneously every day for a minimum period of twelve weeks following which a sustained-release, once-monthly depot formulation of Zoladex 3.6 mg s.c. was used. Acute rises in serum gonadotropins and testosterone during the first two days were followed by declines in hormone levels over the following three weeks. Median time to castration with 500 micrograms/day was twenty-two days compared with forty-three days with 250 micrograms/day (p = 0.06). No significant endocrinologic changes occurred during the transfer to the depot, and serum testosterone remained 95 per cent suppressed throughout the duration of the study. After three months the median daily serum Zoladex concentrations ranged between 0.47 and 0.53 ng/ml and were not significantly different among the three dosage forms. No specific correlation among serum Zoladex concentrations, endocrinologic parameters, and tumor response rates were found. Hot flashes initially, and decreased libido were the only common complaints. Zoladex was well tolerated, and no side effects required dose-modification or removal from the study. Tumor response rates up to one year appeared to be comparable to the conventional endocrine therapies. This analog in monthly depot formulation is recommended for further clinical evaluation.  相似文献   
8.
Segments 15 mm in length were excised from the femoral veins of rats and preserved by refrigeration at 4 C in lactated Ringer's solution for periods up to 21 days. The findings show that veins can be preserved for up to seven days and successfully grafted to recipients. Although there was some success in preserving vein segments for more than seven days, a high rate of thrombosis occurred after implantation in the recipients. It is generally accepted that damaged endothelium causes thrombosis. The light and electron microscopic observations in this study, however, suggest that the condition of the endothelium may not be the only important factor in the patency of small vessels. A thickened and prominent elastic lamina may also play a role in keeping the lumen open.  相似文献   
9.
Mydriasis in giant-cell arteritis   总被引:1,自引:0,他引:1  
A previously healthy 60-year-old woman developed headache, cervical pain, bilateral mydriasis (right greater than left), and bilateral conjunctival injection as the sole manifestations of acute giant-cell arteritis.  相似文献   
10.
The protean manifestations of a novel maternally inherited point mutation of the mitochondrial genome are reported. The proband showed isolated, spastic paraparesis. A brother, who had suffered from a multisystem progressive disorder, ultimately died of cardiomyopathy. Another brother is healthy. The proband's mother showed truncal ataxia, dysarthria, severe hearing loss, mental regression, ptosis, ophthalmoparesis, distal cyclones, and diabetes mellitus. A muscle biopsy performed in the proband failed to show the morphological abnormalities typical of mitochondrial disorders; the activities of respiratory chain complexes were normal. However, complex I and IV activities were low in the muscle homogenate of the affected mother and brother. Sequence analysis of mtDNA showed a heteroplasmic mutation of the tRNA(Ile) gene (G4284A). The mutation load was approximately 55%, 80%, and 90% in the muscle mtDNA of the proband, his mother, and his affected brother, respectively. Mutation was undetected in the healthy brother, as well as in 100 control samples. Several cybrid clones containing homoplasmic mutant mtDNA from the proband showed significant reductions of complex IV activity and maximum oxygen consumption rate, compared with homoplasmic wild-type clones derived from the same subject.  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司    京ICP备09084417号-23

京公网安备 11010802026262号