首页 | 本学科首页   官方微博 | 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   1149篇
  免费   53篇
耳鼻咽喉   17篇
儿科学   12篇
妇产科学   12篇
基础医学   174篇
口腔科学   121篇
临床医学   67篇
内科学   205篇
皮肤病学   21篇
神经病学   131篇
特种医学   29篇
外科学   92篇
预防医学   206篇
眼科学   13篇
药学   55篇
中国医学   6篇
肿瘤学   41篇
  2023年   14篇
  2022年   26篇
  2021年   43篇
  2020年   32篇
  2019年   45篇
  2018年   39篇
  2017年   28篇
  2016年   30篇
  2015年   43篇
  2014年   68篇
  2013年   61篇
  2012年   105篇
  2011年   110篇
  2010年   57篇
  2009年   49篇
  2008年   67篇
  2007年   79篇
  2006年   52篇
  2005年   49篇
  2004年   40篇
  2003年   39篇
  2002年   28篇
  2001年   11篇
  2000年   16篇
  1999年   7篇
  1998年   2篇
  1997年   2篇
  1996年   2篇
  1995年   4篇
  1994年   4篇
  1991年   2篇
  1990年   4篇
  1989年   3篇
  1987年   5篇
  1986年   5篇
  1985年   3篇
  1984年   4篇
  1980年   1篇
  1979年   3篇
  1978年   3篇
  1977年   1篇
  1975年   2篇
  1974年   1篇
  1971年   1篇
  1970年   1篇
  1969年   3篇
  1965年   1篇
  1964年   1篇
  1956年   1篇
  1927年   1篇
排序方式: 共有1202条查询结果,搜索用时 217 毫秒
91.
A retrospective survey of the records of 33 patients with generalized acquired myasthenia gravis treated at Hospital das Clínicas, Medical School of The University of S?o Paulo, Brazil and in private practice, with and without thymectomy, is reported. Nineteen were thymectomized and 14 non operated. Both groups were demographically homogeneous and were followed from 8 to 24 years. Parameters for evaluating the natural history of disease and other ones for a comparative analysis of the improvement or remissions were established. The influence of the individualized therapy was evaluated by McNemar test (chi 2); the U-Mann-Whitney was used for evaluation of the populational behavior groups; variable parameter with possible influence in the useful life were studied by multivariate analysis. The difference of distance between both groups was not significant: (D2 = 0.08894); T2 = 7.17 (Hottelling test). There were differences of the isolate clinic parameter response in both groups, but the global analysis of the parameters did not permit to discriminate them, possibly because of interaction of the parameters influencing the analytic result. Inspite of the fact that superposition of the parameter occurred when analysed for a long period, we believe the early thymectomy to be beneficial. Our patients who had their operation at a younger age and specially those with recent disease had a maximum improvement.  相似文献   
92.
A purified citric acid soluble extract from human skeletal muscle (AEMA) and a phosphate-buffered saline extract from rabbit muscle acetone powder (EMA) were used to coat polystyrene beads in an enzyme-linked immunosorbent assay (ELISA). From 54 patients with myasthenia gravis, positive results were observed in 14. Five of 6 patients with thymoma had high levels of antibodies. With the diagnostic difficulties in detecting small and medium-sized thymoma, a sensitive assay for detection of antibodies to muscle antigen may be an important supplementary tool to detect tumors at early stages.  相似文献   
93.
94.
Accidents caused by brown spiders (Loxosceles genus) are frequent in Brazil and are associated with dermonecrotic lesions and, eventually, systemic reactions that may be lethal. The major species implicated with human envenoming have been: L. intermedia, L. gaucho and L. laeta. In this study we characterized the venom from Loxosceles similis, a species of spider normally found inside caves. L. similis venom was characterized by two-dimensional gel electrophoresis and enzymatic activity (dermonecrosis and haemolysis). The lethal dose to mice and the capacity of commercial anti-serum to neutralize this venom were also analysed. The cross-reactivity with anti-venoms against L. intermedia, L. laeta and L. gaucho were studied. Our results showed that this venom was able to induce severe dermonecrotic lesions and showed the presence of the bacteria Clostridium septicum in association with the fangs. In addition, we have cloned the DNA coding for a dermonecrotic protein (LsD1), using the genomic DNA of L. similis. The deduced amino acid sequence showed a toxin of approximately 31.2 kDa with an estimated pI of 7.37 and sequence similar to LiD1, a protein from the dermonecrotic family of Loxosceles intermedia spider venom, a synanthropic species of medical importance.  相似文献   
95.

We report the clinical and radiological results on the safety and efficacy of an unusual surgical strategy coupling anterior cervical discectomy and fusion and total disc replacement in a single-stage procedure, in patients with symptomatic, multilevel cervical degenerative disc disease (DDD). The proposed hybrid, single-stage, fusion–nonfusion technique aims either at restoring or maintaining motion where appropriate or favouring bony fusion when indicated by degenerative changes. Twenty-four patients (mean age 46.7 years) with symptomatic, multilevel DDD, either soft disc hernia or different stage spondylosis per single level, with predominant anterior myeloradicular compression and absence of severe alterations of cervical spine sagittal alignment, have been operated using such hybrid technique. Fifteen patients underwent a two-level surgery, seven patients received a three-level surgery and two a four-level procedure, for a total of 59 implanted devices (27 disc prostheses and 32 cages). Follow-up ranged between 12 and 40 months (mean 23.8 months). In all but one patient clinical follow-up (neurological examination, Nurick scale, NDI, SF-36) demonstrated significant improvement; radiological evaluation showed functioning disc prostheses (total range of motion 3–15°) and fusion through cages. None of the patients needed revision surgery for persisting or recurring symptoms, procedure-related complications or devices dislocations. To the authors’ best knowledge, this is the first study with the longest available follow-up describing a different concept in the management of cervical multilevel DDD. Although larger series with longer follow-up are needed, in selected cases of symptomatic multilevel DDD, the proposed surgical strategy appears to be a safe and reliable application of combined arthroplasty and arthrodesis during a single surgical procedure.

  相似文献   
96.
97.
98.
99.
100.
The rational of this study we intended to investigate whether the peripheral blood immunological/virological biomarkers were associated with distinct patterns of sleeping quality in patients with chronic hepatitis C-(HCV). Distinct well-established indexes/scores were used to categorize the sleeping quality of HCV patients, including the Pittsburgh Sleep Quality Index (PSQI), Epworth Sleepiness Scale and Fatigue Severity Scores. Our findings demonstrated that HCV patients classified as 'good sleeper' displayed an enhanced frequency of circulating CD8(+) T cells, lower frequency of activated (CD69(+)) neutrophils and eosinophils but enhanced frequency of activated lymphocytes besides lower seric levels of IL-4/IL-8/IL-10 but higher levels of IL-12, besides lower HCV virus load and lower anti-HCV IgG levels. In contrast, HCV patients classified as 'poor sleeper' displayed enhanced levels of activated neutrophils and eosinophils but lower frequency of activated lymphocytes, higher seric levels of IL-6/TNF-α/IL-10 but lower levels of IL-12 besides higher HCV virus load and increased anti-HCV IgG levels. Positive correlation was further confirmed by the relationship between the leucocyte activation status, the cytokine levels, the HCV viral load and the anti-HCV IgG reactivity with the PSQI indexes. Analysis of cytokine signature curves demonstrated that lower frequency of IL-10 was observed in HCV patients classified as 'good sleepers', whereas enhanced frequency of IL-6 was found HCV patients classified as 'poor sleepers'. In conclusion, our data suggest that immunological biomarkers (leucocytes activation status and seric cytokines levels) are likely to be associated with sleeping quality patterns in HCV patients, suggesting their putative use for clinical monitoring purposes.  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