全文获取类型
收费全文 | 770篇 |
免费 | 28篇 |
国内免费 | 28篇 |
专业分类
耳鼻咽喉 | 5篇 |
儿科学 | 31篇 |
妇产科学 | 10篇 |
基础医学 | 70篇 |
口腔科学 | 15篇 |
临床医学 | 55篇 |
内科学 | 101篇 |
皮肤病学 | 15篇 |
神经病学 | 29篇 |
特种医学 | 189篇 |
外科学 | 61篇 |
综合类 | 122篇 |
预防医学 | 24篇 |
眼科学 | 5篇 |
药学 | 56篇 |
1篇 | |
肿瘤学 | 37篇 |
出版年
2023年 | 5篇 |
2021年 | 3篇 |
2020年 | 3篇 |
2018年 | 7篇 |
2017年 | 8篇 |
2016年 | 6篇 |
2015年 | 6篇 |
2014年 | 11篇 |
2013年 | 25篇 |
2012年 | 25篇 |
2011年 | 17篇 |
2010年 | 26篇 |
2009年 | 34篇 |
2008年 | 25篇 |
2007年 | 38篇 |
2006年 | 26篇 |
2005年 | 20篇 |
2004年 | 19篇 |
2003年 | 14篇 |
2002年 | 14篇 |
2001年 | 12篇 |
2000年 | 14篇 |
1999年 | 14篇 |
1998年 | 41篇 |
1997年 | 37篇 |
1996年 | 42篇 |
1995年 | 24篇 |
1994年 | 21篇 |
1993年 | 21篇 |
1992年 | 13篇 |
1991年 | 9篇 |
1990年 | 13篇 |
1989年 | 28篇 |
1988年 | 26篇 |
1987年 | 18篇 |
1986年 | 29篇 |
1985年 | 28篇 |
1984年 | 14篇 |
1983年 | 9篇 |
1982年 | 17篇 |
1981年 | 9篇 |
1980年 | 12篇 |
1979年 | 2篇 |
1978年 | 6篇 |
1977年 | 9篇 |
1976年 | 9篇 |
1975年 | 7篇 |
1955年 | 2篇 |
1953年 | 2篇 |
1952年 | 1篇 |
排序方式: 共有826条查询结果,搜索用时 15 毫秒
101.
Magnetic resonance imaging of spinal-cord hemangioblastoma 总被引:2,自引:0,他引:2
102.
103.
104.
105.
Pseudoaneurysm is a well-documented but rare complication of retrograde femoral arterial puncture. We present six patients in whom pseudoaneurysm complicated this procedure. The pseudoaneurysm arose from the superficial femoral artery in five patients and from the profunda femoris artery in one. An arteriovenous fistula also arose from the superficial femoral artery in one patient. In no patient did the pseudoaneurysm arise from the common femoral artery. Two mechanisms are postulated as to why pseudoaneurysms rarely complicate puncture of the common femoral artery. 相似文献
106.
ME Black SS Hedgire S Camposano E Paul M Harisinghani EA Thiele 《Clinical genetics》2012,82(6):552-557
Black ME, Hedgire SS, Camposano S, Paul E, Harisinghani M, Thiele EA. Hepatic manifestations of tuberous sclerosis complex: a genotypic and phenotypic analysis. A retrospective review of the clinical records and radiological images of 205 patients with tuberous sclerosis complex (TSC) was performed to evaluate the prevalence and progression of hepatic lesions; examine the association of hepatic phenotype with genotype, age, and gender; and investigate the relationships between hepatic, renal, and pulmonary involvement. Hepatic angiomyolipomas (AML), cysts, and other benign lesions were identified in 30% of the cohort, and some lesions grew significantly over time. However, no patient had clinical symptoms or complications from hepatic lesions. TSC2 patients exhibited a higher frequency of AML compared to TSC1 patients (p = 0.037), and patients with no mutation identified exhibited a higher frequency of cysts compared to TSC2 patients (p = 0.023). Age was positively correlated with frequency of hepatic involvement (p < 0.001), whereas hepatic phenotype was independent of gender. Presence of hepatic AML was associated with presence of renal AML (p = 0.001). These findings confirm a high rate of asymptomatic hepatic lesions in TSC and further characterize the TSC phenotype. 相似文献
107.
108.
Evaluation of atypical human immunodeficiency virus immunoblot reactivity in blood donors 总被引:6,自引:0,他引:6
NL Dock ; HV Lamberson Jr ; TA O''Brien ; DE Tribe ; SS Alexander ; BJ Poiesz 《Transfusion》1988,28(5):412-418
Blood donors reactive by enzyme-linked immunosorbent assay for antibody to the human immunodeficiency virus (HIV) who showed atypical patterns of viral core protein reactivity on Western blot were monitored for several months. Characterization of their antibodies was performed by 1) use of recombinant HIV proteins; 2) determination of cross-reactivity to HTLV-I, HTLV-II, and HTLV-IV: 3) assessment of immune status; and 4) identification of potentially interfering autoantibodies. Nineteen of 20 donors maintained the same HIV antibody reactivity throughout the follow-up period; the other donor became fully antibody-positive. Eighteen of 20 donors' sera showed clear reactivity with HIV recombinant core proteins. Ten of 19 donor samples demonstrated cross-reactivity to HTLV-IV; 3 of these 10 also cross-reacted with HTLV-I. The immune status of all donors was normal, although the medical histories and HLA antibody screens suggested possible autoimmune reactivity in 9 of 18 donors. During follow-up interviews, three donors reported possible risk factors for HIV infection that had not been acknowledged at the time of blood donation. We conclude that exclusion of donors with these atypical serologic test results is warranted while further studies to determine significance are being conducted. 相似文献
109.
Natural killer cell precursors in the CD44neg/dim T-cell receptor population of mouse bone marrow 总被引:1,自引:0,他引:1
Natural killer (NK) cells develop from the nonadherent cell component of NK long-term bone marrow (BM) cultures (NK-LTBMC). Because these nonadherent cells are depleted of mature NK cells and T cells, but appear to enriched for NK precursors, they were used as a starting population to begin to define the NK precursors that function in NK- LTBMC. As the stromal cell component of NK-LTBMC has been shown to support interleukin (IL)-2-induced, CD44 dependent, NK cell development from nonadherent NK precursors, NK-LTBMC stroma was used in a limiting dilution assay (LDA) to quantitate the precursors. NK-LTBMC in 96-well plates were irradiated (20 Gy) to kill hematopoietic cells (including the NK precursors), seeded with limiting dilutions of the cells to be quantitated, cultured with 500 U/mL IL-2 for 13 days and assayed for development of NK activity by adding 51Cr-labeled YAC-1 cells to the wells and evaluating the release of 51Cr after 4 hours. Flow cytometric analysis, sorting, and quantitation of the nonadherent cell component of NK-LTBMC showed that NK precursors were concentrated in the CD44neg/dim subset that comprised 10% of the "lymphoid" gated cells. When the CD44neg/dim subset was sorted from BM of mice treated with 5- fluorouracil (5-FU) day before (-1FUBM), there were about 30% T cells, but no NK-1.1+ cells. When the T cells were removed by sorting and the CD44neg/dim, alphabeta, gammadelta T-cell receptorneg (TCR-) subpopulation was seeded onto irradiated stroma with IL-2, they proliferated, developed NK activity, became NK-1.1+ and CD44bright and remained alphabeta, gammadelta TCR-. The frequency of NK precursors in this population as estimated from the LDA was about 1/500. 相似文献
110.
G Lesage SS Glaser S Gubba WE Robertson JL Phinizy J Lasater RE Rodgers G Alpini 《Gastroenterology》1996,111(6):1633-1644
BACKGROUND & AIMS: After partial hepatectomy, liver regeneration occurs with the return of hepatocyte mass to normal, Limited data exist regarding the renewal of the biliary tree after partial hepatectomy. This study tested the hypothesis that, after partial hepatectomy, the biliary tree regenerates by proliferation of the remaining cholangiocytes, leading to an increase in secretin-induced ductal bile secretion. METHODS: After 70% partial hepatectomy, cholangiocyte proliferation was assessed in situ by morphometric analysis and In vitro by measurement of 3H-thymidine incorporation. Ductal secretion was estimated by measurement of secretin receptor gene expression and adenosine 3',5'-cyclic monophosphate (cAMP) levels in vitro and by the effect of secretin on ductal bile secretion in vivo. RESULTS: DNA synthesis was undetectable in control cholangiocytes, increased and peaked at day 3 after partial hepatectomy, and returned to normal by day 28. Morphometric analysis showed regrowth of the biliary tree beginning at day 1 with restoration by day 10. The expression of secretin receptor gene and secretin-induced cAMP levels and secretin- induced bicarbonate-rich choleresis increased during the period of bile duct renewal. CONCLUSIONS: After partial hepatectomy, the increase in secretin-induced ductal bile secretion observed during bile duct renewal results from proliferation of remaining cholangiocytes. (Gastroenterology 1996 Dec;111(6):1633-44) 相似文献