全文获取类型
收费全文 | 64711篇 |
免费 | 4051篇 |
国内免费 | 332篇 |
专业分类
耳鼻咽喉 | 634篇 |
儿科学 | 1710篇 |
妇产科学 | 1569篇 |
基础医学 | 8713篇 |
口腔科学 | 2139篇 |
临床医学 | 6146篇 |
内科学 | 14230篇 |
皮肤病学 | 1416篇 |
神经病学 | 6369篇 |
特种医学 | 1963篇 |
外科学 | 8594篇 |
综合类 | 266篇 |
一般理论 | 26篇 |
预防医学 | 5130篇 |
眼科学 | 1047篇 |
药学 | 4233篇 |
1篇 | |
中国医学 | 248篇 |
肿瘤学 | 4660篇 |
出版年
2024年 | 88篇 |
2023年 | 702篇 |
2022年 | 1326篇 |
2021年 | 2458篇 |
2020年 | 1470篇 |
2019年 | 2076篇 |
2018年 | 2434篇 |
2017年 | 1714篇 |
2016年 | 1872篇 |
2015年 | 2145篇 |
2014年 | 2929篇 |
2013年 | 3657篇 |
2012年 | 5317篇 |
2011年 | 5491篇 |
2010年 | 2799篇 |
2009年 | 2534篇 |
2008年 | 4179篇 |
2007年 | 4092篇 |
2006年 | 3709篇 |
2005年 | 3537篇 |
2004年 | 2940篇 |
2003年 | 2668篇 |
2002年 | 2354篇 |
2001年 | 702篇 |
2000年 | 630篇 |
1999年 | 637篇 |
1998年 | 418篇 |
1997年 | 342篇 |
1996年 | 293篇 |
1995年 | 268篇 |
1994年 | 257篇 |
1993年 | 194篇 |
1992年 | 351篇 |
1991年 | 274篇 |
1990年 | 262篇 |
1989年 | 251篇 |
1988年 | 194篇 |
1987年 | 182篇 |
1986年 | 165篇 |
1985年 | 170篇 |
1984年 | 115篇 |
1983年 | 94篇 |
1982年 | 71篇 |
1981年 | 56篇 |
1980年 | 59篇 |
1979年 | 59篇 |
1978年 | 74篇 |
1977年 | 43篇 |
1976年 | 47篇 |
1973年 | 44篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
91.
Antonio Fea Andrea Grosso Marilena Rabbione Federico Grignolo 《Albrecht von Graefes Archiv fur klinische und experimentelle Ophthalmologie》2007,245(2):315-317
Background Optic disc anomalies are frequently associated with Alagille syndrome. We report here the first case of a patient with Alagille
syndrome combined with optic pit and serous macular detachment.
Methods A male patient with Alagille syndrome was referred from the pediatric hepatology department for investigation of visual loss
in the right eye. Anterior segment examination showed evidence of posterior embryotoxon, confirmed by gonioscopic evaluation.
Dilated fundus examination revealed serous macular detachment and optic pit.
Results OCT 3 scans confirmed the clinical findings.
Conclusions Optic pit is uncommon and should prompt a search for genetic disorders or development abnormalities. The association between
the two syndromes in this patient might be due to failure of correct neuroectodermal development, for which a common genetic
pathway is likely. 相似文献
92.
Composite tissue (limb) allografts in rats. III. Development of donor-host lymphoid chimeras in long-term survivors 总被引:2,自引:0,他引:2
C W Hewitt K S Black S F Dowdy G A Gonzalez B M Achauer D C Martin D W Furnas E B Howard 《Transplantation》1986,41(1):39-43
Eight LEW rat recipients possessing long-term-surviving (206-701 days) LBN vascularized hind limb allografts (CTAs) were tested for donor-host lymphoid chimerism. The recipients received various cyclosporine (CsA) treatment protocols in order to induce indefinite CTA acceptance. Histological examination of long-term-surviving CTAs demonstrated normal-appearing bone marrow in the donor limb. Lymphocytes isolated from host hemopoietic tissues (peripheral blood and/or spleen) by ficoll-hypaque density gradient centrifugation were tested against LEW-anti-BN antisera. Comparisons were made to standard curves employing various known concentrations of LBN and LEW cell combinations. The level of lymphocyte agglutination (dependent variable) showed a significant (P less than 0.025-0.005) linear relationship to the concentration of LBN donor cells (independent variable) present. Lymphocyte suspensions isolated from long-term CTA host peripheral blood and/or spleen showed a mean of 19.7% (+/- 9.7-95% confidence interval) donor LBN mononuclear cells present. Thus, it appeared that lymphoid cells originated from, and/or were released from LBN donor bone marrow into the circulation, resulting in chimeric repopulation of hemopoietic tissues. The presence of donor immunocytes in these limb allograft recipients may have been beneficial, and thus could have helped contribute to the long-term CTA survival observed. 相似文献
93.
A genetically mild obesity syndrome of pubertal onset in a highly inbred line of rats differentiated as beta (beta) has been described. It was discovered in both sexes fed a stock diet for rodents. Hyperphagia was not noticeable. Total fat content reached 31 percent of total body weight in mature males. Obesity was associated with normal plasma cholesterol values and hypertriglyceridemia. Fasting blood sugar levels at maturity were within the normal range for rats, but significantly higher than in lean alpha (alpha) controls. This syndrome developed into a mild glucose intolerance and glucosuria in older obese rats. 相似文献
94.
Antonella d’Arminio Monforte Paola Cinque Luca Vago Aleandro Rocca Antonella Castagna Cristina Gervasoni Maria Rosa Terreni Roberto Novati Andrea Gori Adriano Lazzarin Mauro Moroni 《Journal of neurology》1996,244(1):35-39
Twenty patients with AIDS who had intracranial lesions underwent both brain biopsy and cerebro-spinal fluid (CSF) examination
to compare histological diagnosis with the polymerase chain reaction (CSF-PCR) for the identification of infectious agents.
CSF-PCR was performed for herpes simplex virus, varicella zoster virus, cytomegalovirus (CMV), JC virus (JCV), Epstein-Barr
virus (EBV), Toxoplasma gondii and Mycobacterium tuberculosis. A definitive diagnosis was obtained by brain biopsy in 14 patients (2 with astrocytoma, 12 with brain infection). CSF-PCR
was positive for EBV DNA in 3 of 3 cases of primary cerebral lymphoma, positive for JCV DNA in 6 of 7 biopsy-proven (and one
autopsy-proven) cases of progressive multifocal leukoencephalopathy (PML). CSF-PCR was positive for CMV DNA in one biopsy-proven
and one autopsy-proven case of CMV encephalitis (the former also had PML) and positive for M. tuberculosis DNA in one case of tuberculous encephalitis. None of the five toxoplasmic encephalitis cases (one definite, four presumptive)
were T. gondii DNA positive. There was close correlation between histology and CSF-PCR for CMV encephalitis, PML and PCL. Antitoxoplasma
therapy affected the sensitivity of both histological and CSF-PCR methods.
Received: 8 November 1995 Received in revised form: 9 July 1996 Accepted: 19 July 1996 相似文献
95.
96.
The spatial and temporal pattern of expression of the protein products of immediate early genes (IEGs) c-fos, fos B, and egr-1 were mapped in medial preoptic area (MPOA) and ventral bed nucleus of stria terminalis (VBST) during maternal behavior in rats. Immunocytochemical analysis indicated significant increases in the number of cells expressing c-Fos after 2 h of pup exposure, while Fos B levels showed a delayed response, reaching maximal levels after 6 h. 相似文献
97.
98.
99.
Pathological root resorption has clinical symptoms of great importance when it appears in permanent teeth, as its etiology is not always clear. It is important to examine all local and general factors before determining its "idiopathic" cause. A case of spontaneous loss of permanent teeth in a 19 year-old female is presented. Through a meticulous study correlating the clinical history and the evolution of the symptoms, we can suspect that non-dental medical interventions requiring general anesthesia can lead to the loss of permanent teeth through root resorption. 相似文献
100.
In a catamnestic study an analysis of the clinical results as well as of the spermatograms are reported on 545 andrological patients with "atrophy" (that means reduced testis volume) or absence of one testis and a contralaterally normal developed testis. It can be demonstrated that there do not exist any differences concerning the size and consistency of the present testis and with regard to absence or lost of one testis (hemicastration). In case of testicular atrophy exists a more disadvantageous reproductive function. In case of tumor as a reason for hemicastration the teratoma shows better conditions for the quality of the spermatograms and for reproduction. Accordingly the histological findings of the testis after hemicastration/absence are not so large in the present remained testis. In cases of one-sided orchitis the spermatogram quality is better than in one-sided varicocele with atrophy at the same side. 相似文献