全文获取类型
收费全文 | 510819篇 |
免费 | 37422篇 |
国内免费 | 11878篇 |
专业分类
耳鼻咽喉 | 6189篇 |
儿科学 | 10032篇 |
妇产科学 | 11462篇 |
基础医学 | 65252篇 |
口腔科学 | 14303篇 |
临床医学 | 48713篇 |
内科学 | 93954篇 |
皮肤病学 | 10130篇 |
神经病学 | 31816篇 |
特种医学 | 18445篇 |
外国民族医学 | 126篇 |
外科学 | 70660篇 |
综合类 | 39034篇 |
现状与发展 | 41篇 |
一般理论 | 72篇 |
预防医学 | 30076篇 |
眼科学 | 13047篇 |
药学 | 46239篇 |
236篇 | |
中国医学 | 12893篇 |
肿瘤学 | 37399篇 |
出版年
2023年 | 2721篇 |
2022年 | 6374篇 |
2021年 | 9118篇 |
2020年 | 6993篇 |
2019年 | 6665篇 |
2018年 | 8513篇 |
2017年 | 7914篇 |
2016年 | 7255篇 |
2015年 | 10269篇 |
2014年 | 13356篇 |
2013年 | 15254篇 |
2012年 | 21810篇 |
2011年 | 22648篇 |
2010年 | 15781篇 |
2009年 | 13827篇 |
2008年 | 18203篇 |
2007年 | 18689篇 |
2006年 | 17630篇 |
2005年 | 15860篇 |
2004年 | 13169篇 |
2003年 | 12555篇 |
2002年 | 11484篇 |
2001年 | 30735篇 |
2000年 | 30838篇 |
1999年 | 25219篇 |
1998年 | 6092篇 |
1997年 | 5206篇 |
1996年 | 4567篇 |
1995年 | 4102篇 |
1994年 | 3688篇 |
1993年 | 3177篇 |
1992年 | 16342篇 |
1991年 | 15078篇 |
1990年 | 14386篇 |
1989年 | 14136篇 |
1988年 | 12742篇 |
1987年 | 12201篇 |
1986年 | 11191篇 |
1985年 | 10392篇 |
1984年 | 6945篇 |
1983年 | 5621篇 |
1982年 | 2726篇 |
1979年 | 5483篇 |
1978年 | 3349篇 |
1977年 | 2972篇 |
1975年 | 2645篇 |
1974年 | 3067篇 |
1973年 | 2870篇 |
1972年 | 2828篇 |
1971年 | 2773篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
181.
After a comprehensive rernew of the literature on syphilitic
aortitis, Longcope, (1) stated in 1913; ": . . . the presence of spiro:
chetes in these lesions, as might be expected, cannot by any means be
constantly demonstrated with Levaaiti stain. . . . . . . That these
organisms are ''Treponema pallidum seems almost certain thouS:h actual
proof of such by culture from the arterial lesions, a most difficult task,
or direct inoculation into animals, has not as yet been accomplished." 相似文献
182.
183.
184.
185.
D Y Jones K W Miller B P Koonsvitsky M L Ebert P Y Lin M B Jones H F DeLuca 《The American journal of clinical nutrition》1991,53(5):1281-1287
The effect of olestra on vitamin D status was assessed in a 6-wk, double-blind, placebo-controlled study involving 202 free-living adults. Subjects consumed a total of 20 g/d of olestra or triglycerides in cookies eaten at each meal. A 20-micrograms ergocalciferol capsule was taken with each morning meal. Serum 25-hydroxyergocalciferol (25-OHD2) concentrations rose from approximately 5.7 to 39.0 and 31.7 nmol/L in the placebo and olestra groups, respectively, at week 6. At week 6, 25-OHD2 contributed 46-54% to total serum 25-OHD concentration compared with 11% at baseline. The 19% decrease in serum 25-OHD2 concentrations produced by olestra in this study is equivalent to a decrease of approximately 1.2 nmol/L under nonsupplemented dietary conditions. Ingesting 20 g olestra/d in the diet is thus not expected to affect vitamin D nutritional status. 相似文献
186.
187.
Differentiation of blast cells from a Down's syndrome patient with transient myeloproliferative disorder 总被引:2,自引:0,他引:2
Suda J; Eguchi M; Akiyama Y; Iwama Y; Furukawa T; Sato Y; Miura Y; Suda T; Saito M 《Blood》1987,69(2):508-512
A male neonate with Down's syndrome and congenital myeloproliferative disorder was studied. His blood picture showed the unique coexistence of leukocytosis with matured cells and a large number of blast cells. The in vitro proliferation and differentiation of blast cells into various lineages in the presence of phytohemagglutinin-stimulated leukocyte conditioned medium (PHA-LCM) was examined by using a liquid culture and a methylcellulose culture system. The differentiation of blast cells into myeloid cells was confirmed by specific cytochemical stainings, electron microscopy, and an immunologic study. No specific factors in the plasma of the patient promoted the proliferation or differentiation of blast cells. The cellular composition of colonies grown in methylcellulose culture from single blast cells was studied by a micromanipulation technique. High plating efficiency was observed. Of 136 cultures, 78 showed colony growth. Half of the blast cells were colony-forming cells that could proliferate and differentiate into basophils, neutrophils, eosinophils, macrophages, and erythrocytes in the presence of PHA-LCM. Using the blast cells with a high differentiation capacity to the basophil pathway, we studied the effect of recombinant granulocyte-macrophage colony-stimulating factor (GM- CSF). Recombinant GM-CSF support neutrophils, eosinophils, and macrophages but not typical basophils. These findings of the cell differentiation of blast cells into various kinds of cells in vitro were in agreement with the finding of neutrophilia, eosinophilia, basophilia, and thrombocythemia in this patient. 相似文献
188.
Y Yoshimura M Oka T Sugihara K Mishima 《International journal of oral and maxillofacial surgery》1986,15(2):196-200
A case of a branchial cyst with a high amylase activity of the cyst fluid was found in a 58-year-old female. The literature on branchial cysts with high amylase activity is reviewed. Amylase that showed high activity in the cystic fluid was revealed to be due to the salivary isoenzymes (S3 and S4) which migrated more to the anodic side on electrophoresis. 相似文献
189.
Complications following ureteroscopy 总被引:1,自引:0,他引:1
We report 4 cases of ureteral injury and stricture formation following ureteroscopic stone manipulation. Possible etiologies of stricture formation and our methods of managing them are discussed. The complications of ureteroscopy have been reported only rarely and the ureteroscopist should be aware that the procedure is not always benign. 相似文献
190.