全文获取类型
收费全文 | 21692篇 |
免费 | 1432篇 |
国内免费 | 41篇 |
专业分类
耳鼻咽喉 | 133篇 |
儿科学 | 737篇 |
妇产科学 | 727篇 |
基础医学 | 2919篇 |
口腔科学 | 397篇 |
临床医学 | 3516篇 |
内科学 | 4121篇 |
皮肤病学 | 236篇 |
神经病学 | 2180篇 |
特种医学 | 335篇 |
外科学 | 1639篇 |
综合类 | 290篇 |
一般理论 | 31篇 |
预防医学 | 2937篇 |
眼科学 | 189篇 |
药学 | 1348篇 |
中国医学 | 18篇 |
肿瘤学 | 1412篇 |
出版年
2023年 | 97篇 |
2022年 | 171篇 |
2021年 | 356篇 |
2020年 | 235篇 |
2019年 | 403篇 |
2018年 | 416篇 |
2017年 | 299篇 |
2016年 | 375篇 |
2015年 | 436篇 |
2014年 | 641篇 |
2013年 | 1025篇 |
2012年 | 1474篇 |
2011年 | 1459篇 |
2010年 | 824篇 |
2009年 | 793篇 |
2008年 | 1422篇 |
2007年 | 1431篇 |
2006年 | 1421篇 |
2005年 | 1456篇 |
2004年 | 1382篇 |
2003年 | 1366篇 |
2002年 | 1311篇 |
2001年 | 220篇 |
2000年 | 193篇 |
1999年 | 228篇 |
1998年 | 273篇 |
1997年 | 239篇 |
1996年 | 192篇 |
1995年 | 210篇 |
1994年 | 190篇 |
1993年 | 185篇 |
1992年 | 174篇 |
1991年 | 173篇 |
1990年 | 142篇 |
1989年 | 164篇 |
1988年 | 140篇 |
1987年 | 140篇 |
1986年 | 113篇 |
1985年 | 116篇 |
1984年 | 151篇 |
1983年 | 119篇 |
1982年 | 134篇 |
1981年 | 122篇 |
1980年 | 125篇 |
1979年 | 84篇 |
1978年 | 85篇 |
1977年 | 58篇 |
1976年 | 58篇 |
1974年 | 49篇 |
1973年 | 46篇 |
排序方式: 共有10000条查询结果,搜索用时 361 毫秒
71.
Role of substance P in several models of bladder inflammation 总被引:1,自引:0,他引:1
Judith Luber-Narod Tammy Austin-Ritchie Carl Hollins III Mani Menon Rajwant K. Malhotra Stephen Baker Robert E. Carraway 《Urological research》1997,25(6):395-399
Substance P (SP) is a peptide found in the sensory nervous system which has multiple biologic effects including stimulation of muscle contraction, pain nociception, immune cell functions, plasma extravasation and a constellation of inflammatory effects. Here we investigate the role of SP in several animals models of bladder inflammation. Using the female Lewis rat, inflammation was induced using either xylene, lipopolysaccharide (LPS) or polyinosinic-polycytidylic acid (polyIC). Inflammation occurred rapidly (4 h) and was maintained in each model for at least 7 days. Each of these protocols decreased the bladder content of immunoreactive SP by approximately 50%, suggesting enhanced release. There was no change in the urinary frequency of these animals over 3 weeks, suggesting that urinary frequency changes are not mediated by acute inflammation. We also found that the SP receptor (NK1) antagonist, (?)CP96345, was unable to block the inflammation produced by polyIC, suggesting that SP is not an obligatory mediator of immune cell stimulation in this model. 相似文献
72.
Suzanne D. LeBlang M.D. Diego B. Nuñez M.D. Anton Serafini M.D. Robert C. Duncan Ph.D. M. Judith Donovan Post M.D. Berta M. Montalvo M.D. Jose I. Becerra M.D. 《Emergency radiology》1997,4(4):191-199
The purpose of this study was to evaluate the ability of helical computed tomography (CT) to detect arterial injuries in gunshot wounds to the neck. In a blinded retrospective review, 54 helical CT scans of the cervical spine were evaluated for bullet/bone fragments, subcutaneous air, bullet path, hematoma, spine fractures, and pharyngoesophageal compromise. The distance of fragments to a major vessel was calculated. CT findings that correlated significantly with major arterial injury included the presence of fragments (bullet/bone) close to a major vessel (2.5 mm) and spine fractures. Visualizing fragments <5 mm from a vessel or a transcervical bullet trajectory predicted 12 of 13 major arterial injuries. We conclude that CT clearly depicts anatomic damage. Specific findings, such as the location of fragments and bullet trajectory adjacent to a vessel and spine fractures, indicate a higher probability of vascular damage, thus directing more definitive evaluation. 相似文献
73.
74.
75.
P J Sheridan 《Molecular and cellular endocrinology》1991,76(1-3):C39-C45
If the above two hypotheses are correct, they would require at least one more specific nuclear receptor for T, and at least one membrane receptor to account for the very rapid effects induced by androgens on certain target tissues. If this is the case, clearly a single androgen receptor will not fill the bill. 相似文献
76.
77.
J. Richard Udry Ph.D. Judith Kovenock B.S. Naomi M. Morris M.D. M.P.H. Bea J. van den Berg M.D. 《Archives of sexual behavior》1995,24(3):329-337
Age at first intercourse for a sample of adult white women using variables measured during childhood is predicted. Childhood predictors were measured at birth, and ages 5 and 9–11, using existing public-use data on the women. Median age at first intercourse for the sample was 17.5 years. Early family predictors, early developmental characteristics, and temperamental characteristics during childhood together could predict about a fourth of the variance in age at first intercourse. The strongest predictors were motor skills and nightmares at age 5, church attendance with family at age 9, and domineering and mature personality at age 9.This research was supported by grants R01-HD23454 and P30-HD05798 from the National Institute of Child Health and Human Development. An earlier version of this paper was presented at the annual meetings of the Population Association of America, Denver, Colorado, April 30–May 2, 1992. 相似文献
78.
M A Sheridan E M Plisetskaya H A Bern A Gorbman 《General and comparative endocrinology》1987,66(3):405-414
Salmon (Oncorhynchus kisutch) somatostatin (sSS; 4 or 8 ng/g body wt) or synthetic Gillichthys urotensin II (UII; 2 or 4 ng/g body wt) were injected intraperitoneally into juvenile freshwater coho salmon. Both sSS and UII caused a dose-dependent increase in plasma free fatty acids (FFA) which diminished with time. sSS induced an initial (1 hr) transient hyperglycemia. By contrast, UII tended to induce hypoglycemia, this effect being significant 5 hr after injection of the higher dose. Both sSS and UII depressed plasma insulin titers 1 hr after injection. By 3 hr, the sSS-associated insulin depression was no longer observed. UII treatment induced a hyperinsulinemia which was present 3 and 5 hr after peptide administration. Although no decreases in liver total lipid concentration or in mesenteric fat total tissue mass were observed, lipolytic enzyme activity within each depot was significantly enhanced by both peptides. Neither sSS nor UII altered 3H2O incorporation into fatty acids or neutral lipids. However, enhanced lipogenesis, particularly by UII, was indicated by increased NADPH production resulting from glucose-6-phosphate dehydrogenase activity. Both sSS and UII enhanced glucose mobilization, as indicated by decreased liver glycogen content and increased liver glucose-6-phosphatase activity. UII, but not sSS, stimulated glycogen synthetase activity. These results suggest that both sSS and UII stimulate hyperlipidemia by enhancing depot lipase activity and that although both factors are potentially gluconeogenetic, sSS seems to be glycogenolytic and hyperglycemic, whereas UII may channel glucose to FFA synthesis. 相似文献
79.
Oscar A. Alvarez M.D. Judith A. Maples M.D. Fermin O. Tio M.D. Makau Lee M.D. Ph.D. 《The American journal of gastroenterology》1995,90(8):1350-1351
Cokeromyces recurvatus , a sporangiola-forming dimorphic is a rare cause of urogenital infection in humans. We report here a case of severe watery diarrhea due lo C. recurvains , which was treated successfully with high-dose oral nystatin therapy. We speculate that our patient was probably predisposed to infections due to opportunistic organisms, such as C. recurvatus , because of post-transplantation immunosuppression. To our knowledge, our patient represents the first documented case of diarrhea due to C. recurvatus in man und this ease highlights the potential pathogenic capability of this opportunistic organism in immunosuppressed patients. 相似文献
80.