全文获取类型
收费全文 | 4576篇 |
免费 | 175篇 |
国内免费 | 88篇 |
专业分类
耳鼻咽喉 | 69篇 |
儿科学 | 129篇 |
妇产科学 | 43篇 |
基础医学 | 816篇 |
口腔科学 | 22篇 |
临床医学 | 251篇 |
内科学 | 1010篇 |
皮肤病学 | 81篇 |
神经病学 | 289篇 |
特种医学 | 200篇 |
外科学 | 552篇 |
综合类 | 180篇 |
现状与发展 | 1篇 |
预防医学 | 208篇 |
眼科学 | 38篇 |
药学 | 500篇 |
1篇 | |
中国医学 | 102篇 |
肿瘤学 | 347篇 |
出版年
2023年 | 43篇 |
2022年 | 98篇 |
2021年 | 91篇 |
2020年 | 90篇 |
2019年 | 117篇 |
2018年 | 119篇 |
2017年 | 91篇 |
2016年 | 70篇 |
2015年 | 91篇 |
2014年 | 153篇 |
2013年 | 164篇 |
2012年 | 142篇 |
2011年 | 127篇 |
2010年 | 91篇 |
2009年 | 104篇 |
2008年 | 104篇 |
2007年 | 109篇 |
2006年 | 111篇 |
2005年 | 249篇 |
2004年 | 211篇 |
2003年 | 223篇 |
2002年 | 144篇 |
2001年 | 150篇 |
2000年 | 128篇 |
1999年 | 118篇 |
1998年 | 137篇 |
1997年 | 124篇 |
1996年 | 85篇 |
1995年 | 103篇 |
1994年 | 60篇 |
1993年 | 76篇 |
1992年 | 45篇 |
1991年 | 54篇 |
1990年 | 37篇 |
1989年 | 39篇 |
1988年 | 41篇 |
1987年 | 46篇 |
1986年 | 51篇 |
1985年 | 63篇 |
1984年 | 71篇 |
1983年 | 44篇 |
1982年 | 65篇 |
1981年 | 74篇 |
1980年 | 67篇 |
1979年 | 66篇 |
1978年 | 71篇 |
1977年 | 42篇 |
1976年 | 40篇 |
1972年 | 30篇 |
1968年 | 26篇 |
排序方式: 共有4839条查询结果,搜索用时 15 毫秒
41.
42.
Glycoprotein B of bovine herpesvirus type 4: Its phylogenetic relationship to gB equivalents of the herpesviruses 总被引:1,自引:0,他引:1
Michael Goltz Hermann Broll Annette Mankertz Wolfgang Weigelt Hanns Ludwig Hans-Jörg Buhk Kerstin Borchers 《Virus genes》1994,9(1):53-59
In order to estimate the phylogenetic relationship of BHV-4 among the herpesviruses, we have cloned and sequenced its glycoprotein B (gB). The 2.6 kb open reading frame codes for a 874 amino acid long protein. The comparison of its deduced amino acid sequence with those of its counterparts in 19 distinct herpesviruses groups BHV-4 into the -herpesvirinae. The calculation of an evolutionary tree emphasized that BHV-4 is more closely related to herpesvirus saimiri (HVS) than to Epstein-Barr virus (EBV). However, in contrast to EBV and HVS, the gB of BHV-4 contains a putative protease cleavage site and 20 potential N-glycosylation sites. The alignment of the amino acid sequences revealed that 10 cysteine and 7 proline residues, as well as the motifs SPF and GQLG, were completely conserved among the 20 investigated gBs. 相似文献
43.
Florence P. Haseltine Vincent A. Lynch Daniel L. Van Dyke W. Roy Breg Uta Francke John M. Opitz 《American journal of medical genetics. Part A》1982,13(2):115-123
Cells from three patients with early gonadal failure and a balanced reciprocal translocation involving the long arm of the X chromosome and an autosome were studied. Fibroblasts from a patient with a similar balanced reciprocal translocation but normal reproductive capabilities were also studied. Two of the four patients were found to have serologically detectable H-Y antigen on their cells. Since H-Y antigen has been found on the cells of other patients with X chromosome abnormalities but without a Y chromosome, it is thought that the X chromosome plays a role in the regulation of H-Y antigen expression. This study suggests that the long arm of the X chromosome may be involved but the location of a regulatory gene cannot be identified in these studies. These cases do not permit us to implicate H-Y antigen as a cause of gonadal dysgenesis and early gonadal failure in females who have structurally abnormal X chromosomes. 相似文献
44.
H. Dobbelstein 《Journal of molecular medicine (Berlin, Germany)》1972,50(10):533-535
Zusammenfassung Eine Umfrage, die sich auf 55 Dialysezentren mit insgesamt 901 Patienten (90% aller in der BRD behandelten Patienten in einem chron. intermittierenden Dialyseprogramm) erstreckte, ergab, daß 7,6% der Kranken an einer klinisch manifesten Neuropathie leiden. Bei 127 von 307 untersuchten Patienten war die motorische Nervenleitgeschwindigkeit an den Beinen herabgesetzt.Die Aufgliederung der Patienten nach der wöchentlichen Dialysedauer und nach verschiedenen Dialysatortypen ergab eine statistisch signifikante Abnahme der Neuropathiehäufigkeit mit zunehmender Dialysedauer—sowohl bei den Spulen—wie auch bei den Plattengeräten. Bei klinisch manifester Neuropathie ließen sich die Symptome in der Regel durch eine Verlängerung der wöchentlichen Dialysedauer um 6 Std bessern.Fehlten Symptome seitens des peripheren Nervensystems, so ließ sich bei einer wöchentlichen Dialysedauer von 26 Std oder mehr, das Auftreten einer klinisch manifesten Neuropathie praktisch völlig verhüten. 相似文献
45.
46.
W. Schuetz K. Traeger T. Anhaeupl S. Schanda C. Rager J. Vogt M. Georgieff 《European journal of applied physiology》1995,70(1):81-87
Adrenaline infusion of 0.1 g · kg–1 · min–1 in healthy volunteers results in an increase of hepatic glucose production, an increase of the absolute number of occupied -adrenoceptors and specific changes in metabolism. To compare these effects with the changes induced by an endogenous catecholamine release, we investigated healthy volunteers during cycle ergometry. After fasting at least 14 h seven healthy subjects exercised for 90 min at an intensity of 20% below their individual anaerobic threshold. The rate of glucose production as well as the turnover rates of alanine and leucine were calculated using stable isotope tracers. High and low affinity -adrenergic binding sites on lymphocytes were determined by an equilibrium binding assay with (–)125 Iodocyanopindolol. After 90 min of cycling the rate of appearance of glucose increased significantly from means of 2.0 (SD 0.2) to 2.65 (SD 0.50) mg · kg–1 · min–1 with unchanged blood concentrations of glucose and lactate. The flux of the amino acids alanine and leucine decreased significantly from means of 0.91 (SD 0.21) to 0.62 (SD 0.14) mg · kg–1 · min–1 and from 0.40 (SD 0.05) to 0.32(SD 0.04) mg · kg–1 · min–1, respectively. The mean free fatty acid concentration increased significantly from 0.65 (SD 0.33) to 1.27 (SD 0.45) mmol · l–1 during the endurance trial. The increase of glucose turnover and the decrease of amino acid flux point to a metabolic shift towards enhanced utilization of free fatty acids. Adrenaline and noradrenaline concentrations showed a moderate but significant increase from means of 0.61 (SD 0.20) to 0.99 (SD 0.36) nmol · l–1 and from 2.27 (SD 0.75) to 3.46 (SD 0.38) nmol · 1–1, respectively. The number of high affinity -adrenergic binding sites per cell (-adrenoceptors) nearly doubled from 770 (SD 130) to 1490 (SD 150) during 90 min of cycling. The observed endogenous plasma catecholamine concentrations were not sufficient to change significantly the relative receptor occupancy. This would seem to indicate that the aerobic exercise induced effects depended more on the absolute number of occupied -adrenoceptors than on their relative receptor occupancy. When compared to the results of the adrenaline infusion experiment the increases of the hepatic glucose production and the increase of -adrenoceptors were very similar in both groups despite ten times higher adrenaline plasma concentrations in the infusion group. This would seem to indicate that -adrenoceptors mediated effects do not correlate with catecholamine plasma concentrations. 相似文献
47.
Bonnet F Savès M Morlat PH Droz C Chêne G Peuchant E Bernard N Lacoste D Salamon R Beylot J 《Journal of clinical immunology》2002,22(2):75-82
We assessed the correlations between some plasma markers of immune activation (soluble receptors of interleukin 2 (sIL2-R) and TNFp75 (sTNFII-R) and usual markers of HIV infection in patients treated with protease-inhibitors (PI). Forty-six PI-naive HIV-1-infected adults were included in a 1-year prospective cohort from the initiation of a PI-containing regimen (M0). Measurements of CD4+cell count, plasma HIV-RNA, sIL2-R and sTNFII-R were performed at M0, M6, and M12. The evolution of sIL2-R from baseline to M12 was significantly different between immunological responders (IR) (CD4+count above 200/mm3 for subject having less than 200 CD4 +/mm3 at inclusion, or increase of at least 50 CD4+/mm3 for others) (58 UI/ml) and non-IR (+28 UI/ml) (P =0.01). The evolution of sTNFII-R between M0 and M12 was significantly different between virological responders (VR) (plasma HIV-1 RNA less than 500 copies/ml at M12) (–2.5 ng/ml) and non-VR (+0.2 ng/ml) (P =0.02). Our study shows significative correlations between the evolutions of soluble interleukin-2 and TNFR-II receptors and those of CD4+T-lymphocytes or HIV-RNA responses in patients under HAART. 相似文献
48.
Aidan P. McManus Barry A. Gusterson C. Ross Pinkerton Janet M. Shipley 《The Journal of pathology》1995,176(2):137-142
It is increasingly recognized that the identification of t(11;22)(q24;q12) is a useful aid in the accurate diagnosis of Ewing's sarcoma and related tumours. However, cytogenetic studies have a low success rate and adequate tumour is not always available. This study describes the use of fluorescence in situ hybridization (FISH) to detect translocations at 22q12, the site of the EWS gene involved in t(11;22)(q24;q12), on tumour touch imprints made from true cut core-needle biopsy and frozen tumour. Of the seven tumours analysed, five diagnosed as Ewing's sarcoma or primitive neuroectodermal tumour demonstrated chromosome translocation at 22q12. This is a rapid and reliable method to detect a diagnostically relevant chromosome translocation using minimal amounts of fresh or frozen tumour. 相似文献
49.
Renate Wachner Christian Wittekind Sabine von Kleist 《Virchows Archiv : an international journal of pathology》1984,402(4):415-423
Summary One hundred and twenty seven cases of lung tumors were studied by the immunoperoxidase technique for the presence of CEA and-HCG. Twenty-nine of these tumors were additionally stained for keratin and SP1. CEA and SP1 could be demonstrated in 80% of the studied cases, while-HCG was found in only 9%. SP1 revealed an almost identical staining pattern to CEA and keratin was found only in squamous cell carcinomas. The tissue positivity of none of these three markers correlated with tumor size, lymphnodal involvement or histological type.This study was supported by Deutsche Stiftung für Krebsforschung - Dr. Mildred Scheel-Stiftung 相似文献
50.
K.?Magari F.?Nishigaki T.?Sasakawa T.?Ogawa S.?MiyataEmail author Y.?Ohkubo S.?Mutoh T.?Goto 《Inflammation research》2003,52(12):524-529
Objective and design:To determine the effect of FK506 (tacrolimus) on paw inflammation, TNF- expression in joint, and bone and cartilage destruction in type II collagen-induced arthritis (CIA) model in rats.Methods:CIA was induced by immunization of female Lewis rats with an emulsion of bovine type II collagen and incomplete Freunds adjuvant. Paw inflammation was assessed by the increase in paw volume. Tumor necrosis factor (TNF) - expression in hind knee joint was assessed by immunohistochemical analysis. Lesions of bone and cartilage were assessed on the basis of histological change in knee joint, radiographic analysis in hind paw, bone mineral density in femora and proteoglycan contents in the cartilage of femoral heads. FK506 at doses of 1, 1.8 and 3.2 mg/kg or its placebo formulation was orally administered to rats for 28 days from the day after immunization (n = 10). Effect of FK506 was compared with that of vehicle (distilled water).Results:FK506 at a dose of 1.8 mg/kg significantly suppressed paw swelling (p < 0.01) and histological change in knee joint (p < 0.05). Tumor necrosis factor (TNF)- was mainly expressed in the region with a marked infiltration of inflammatory cells in the hind knee joint. FK506 (3.2 mg/kg) markedly reduced TNF- expression. FK506 at a dose of 1.8 mg/kg suppressed radiographic changes in hind paw (p < 0.05) and also recovered the decrease in bone mineral density in the femora (p < 0.05). Proteoglycan contents in the cartilage of femoral heads were determined to evaluate the cartilage destruction more quantitatively and found to significantly decrease in CIA rats. FK506 at a dose of 1.8 mg/kg recovered the loss of proteoglycan contents (p < 0.01).Conclusion:These results show that FK506 is effective in suppressing inflammation, TNF- expression in joint, and damage to bone and cartilage in rat CIA, and may be useful in the treatment of rheumatoid arthritis. 相似文献