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   89148篇
  免费   10444篇
  国内免费   4833篇
耳鼻咽喉   915篇
儿科学   1632篇
妇产科学   837篇
基础医学   5312篇
口腔科学   1914篇
临床医学   11855篇
内科学   9017篇
皮肤病学   1198篇
神经病学   2527篇
特种医学   3746篇
外国民族医学   1篇
外科学   8203篇
综合类   21602篇
现状与发展   13篇
一般理论   3篇
预防医学   12084篇
眼科学   1090篇
药学   9166篇
  119篇
中国医学   8445篇
肿瘤学   4746篇
  2024年   489篇
  2023年   1436篇
  2022年   2775篇
  2021年   3573篇
  2020年   3269篇
  2019年   1763篇
  2018年   2222篇
  2017年   2794篇
  2016年   2275篇
  2015年   3858篇
  2014年   4762篇
  2013年   6183篇
  2012年   7609篇
  2011年   7938篇
  2010年   7364篇
  2009年   6697篇
  2008年   6447篇
  2007年   6159篇
  2006年   5445篇
  2005年   4294篇
  2004年   3036篇
  2003年   2513篇
  2002年   2013篇
  2001年   1971篇
  2000年   1353篇
  1999年   714篇
  1998年   445篇
  1997年   454篇
  1996年   449篇
  1995年   369篇
  1994年   297篇
  1993年   275篇
  1992年   248篇
  1991年   241篇
  1990年   218篇
  1989年   222篇
  1988年   214篇
  1987年   197篇
  1986年   184篇
  1985年   174篇
  1984年   140篇
  1983年   133篇
  1982年   108篇
  1981年   98篇
  1980年   79篇
  1979年   91篇
  1978年   59篇
  1977年   80篇
  1976年   62篇
  1975年   56篇
排序方式: 共有10000条查询结果,搜索用时 14 毫秒
91.
92.
This paper examines medical malpractice law as it applies to medically necessary oral health care. The basic legal concepts and reported cases involving medically necessary oral health care are reviewed. It is concluded that dental professionals and consumer advocates must advance their educational and legislative advocacy efforts so that health professional colleagues and the public will become aware of the importance of these services and insurers will routinely include coverage of medically necessary oral health care in their medical and dental policies. While failure to provide medically necessary oral health care can be violative of patient rights and legally actionable, medical malpractice litigation should always be the behavior modifier of last resort.  相似文献   
93.
94.
We report an infant with multiple congenital anomalies, including craniosynostosis, tetralogy of Fallot variant, and limb anomalies associated with a maternal deletion of 15q15-22.1. Only two other patients have been reported with a similar deletion, but the deletion was paternal in both cases. We review our patient's findings and compare them to previously reported individuals with similar 15q abnormalities. Our patient allows an expansion of phenotype associated with mid-15q deletions to include severe craniosynostosis, congenital heart disease, and limb anomalies. This will assist in prenatal counseling and predicting postnatal outcome for other affected individuals. The specific breakpoints in our patient and the other patients with similar deletions may also assist in determining a critical region for suture formation.  相似文献   
95.
Cytopathic effect of in situ gene therapy in prostate cancer   总被引:3,自引:0,他引:3  
This is a morphologic study of in situ gene therapy effects in patients with prostate cancer using the Herpes Simplex VirusThymidine Kinase gene (HSV-tk) followed by ganciclovir. Prostatectomy specimens from the first 4 patients showed the following morphologic changes: (1) various degrees of necrosis were seen in cancer foci; (2) cytopathic changes were seen across the whole spectrum of Gleason grades; (3) the normal prostate was rarely affected by necrosis, but contained an intense mononuclear infiltrate; (4) loss of nuclear detail was a common finding. Volumetric studies showed that only portions of the tumor show morphologic effects as well as an inverse relationship between percentage of affected tumor and prostate and tumor size. An inflammatory response was observed, with predominance of CD20-positive cells in normal prostate tissue, CD8 (cytotoxic T cells) in the tumor, and macrophages in all areas of the treated prostates. We believe that these changes represent the cytopathic effect of our in situ gene therapy on prostate cancer, and that they trigger a local immune response.  相似文献   
96.
Purified polymers have been isolated from 6-aminopenicillanic acid and from semi-synthetic penicillins and cephalosporins. All the polymers were shown to react with rabbit antibody of penicillins and cephalosporins. All the polymers were shown to react with rabbit antibody of penicilloyl specificity, as demonstrated by passive cutaneous anaphylaxis in guinea pigs, and the reactions were shown to be penicilloyl-specific by hapten inhibition experiments. The cephalosporin-derived polymers in addition reacted with rabbit antibodies raised to the corresponding cephalosporin conjugates of bovine gamma-globulin. Using direct skin tests, passive cutaneous anaphylaxis and an in vitro assay, no evidence was obtained that the polymers induced the formation of specific antibodies in baboons, guinea pigs and rabbits, but in baboons the induction of cell-mediated immunity, demonstrable by delayed skin test reactions, was shown.  相似文献   
97.
Papillary cystadenoma of the epididymis is an uncommon benign lesion that may occur sporadically or as a manifestation of von Hippel—Lindau (VHL) disease. Neither immunohistochemical studies nor molecular genetic analyses of the VHL gene have been reported previously for this lesion. The authors describe two cases of clear cell papillary cystadenoma of the epididymis, both of which were initially confused with metastatic renal cell carcinoma. Both lesions showed positive immunohistochemical staining for low and intermediate molecular weight keratins (Cam 5.2 and AE1/AE3), EMA, vimentin, α1-antitrypsin, and α1-antichymotrypsin. Each was negative for CEA. Because clear cell papillary cystadenoma is similar to renal cell carcinoma histologically, and because both occur as components of the von Hippel—Lindau disease complex, the authors analyzed both cases for the presence of mutations in the VHL gene. A somatic VHL gene mutation was detected in one of the two tumors by polymerase chain reaction followed by single-strand conformation polymorphism analysis. Direct sequencing revealed a cytosine to thymine transition at nucleotide 694, resulting in the replacement of an arginine with a stop codon after the sixth amino acid of exon 3. As the VHL gene is believed to function as a tumor suppressor gene, VHL gene mutations may play a role in the initiation of tumorigenesis in sporadic cystadenomas of the epididymis.  相似文献   
98.
99.
An acid-insoluble, methacrylic acid, methyl methacrylate copolymer (Eudragit L-100) was used to give an enteric coating to a grass pollen extract in order to protect it against gastric degradation. Substantial protection against the degradative effects of simulated gastric secretion was demonstrated using this preparation which was well tolerated by grass pollen-allergic volunteers. The enteric-coated allergen induced a greater secondary antibody response than did an aqueous presentation when administered orally to guinea pigs which had been primed previously by subcutaneous injection. This result indicates that an effective hyposensitisation regimen could consist of a short series of initial parenteral injections, followed by an oral course of the protected allergen.  相似文献   
100.
Performance-Based Incentive Compensation (PBIC) plans currently prevail throughout industry and have repeatedly demonstrated effectiveness as powerful motivational tools for attracting and retaining top talent, enhancing key indicators, increasing employee productivity, and, ultimately, enhancing mission-based parameters. The University of Arkansas for Medical Sciences (UAMS) College of Medicine introduced its PBIC plan to further the transition of the college to a high-performing academic and clinical enterprise. A forward-thinking compensation plan was progressively implemented during a three-year period.After the introduction of an aggressive five-year vision plan in 2002, the college introduced a PBIC plan designed to ensure the retention and recruitment of high-quality faculty through the use of uncapped salaries that reflect each faculty member's clinical, research, and education duties. The PBIC plan was introduced with broad, schoolwide principles adaptable to each department and purposely flexible to allow for tailor-made algorithms to fit the specific approaches required by individual departments.As of July 2006, the college had begun to reap a variety of short-term benefits from Phase I of its PBIC program, including increases in revenue and faculty salaries, and increased faculty morale and satisfaction.Successful implementation of a PBIC plan depends on a host of factors, including the development of a process for evaluating performance that is considered fair and reliable to the entire faculty. The college has become more efficient and effective by adopting such a program, which has helped it to increase overall productivity. The PBIC program continues to challenge our faculty members to attain their highest potential while rewarding them accordingly.  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