全文获取类型
收费全文 | 153115篇 |
免费 | 10054篇 |
国内免费 | 771篇 |
专业分类
耳鼻咽喉 | 1406篇 |
儿科学 | 3898篇 |
妇产科学 | 2762篇 |
基础医学 | 20568篇 |
口腔科学 | 3456篇 |
临床医学 | 14723篇 |
内科学 | 32947篇 |
皮肤病学 | 2876篇 |
神经病学 | 14803篇 |
特种医学 | 6128篇 |
外国民族医学 | 6篇 |
外科学 | 23002篇 |
综合类 | 1904篇 |
现状与发展 | 2篇 |
一般理论 | 139篇 |
预防医学 | 11051篇 |
眼科学 | 3197篇 |
药学 | 10488篇 |
2篇 | |
中国医学 | 245篇 |
肿瘤学 | 10337篇 |
出版年
2023年 | 818篇 |
2022年 | 1238篇 |
2021年 | 2828篇 |
2020年 | 1956篇 |
2019年 | 2816篇 |
2018年 | 3427篇 |
2017年 | 2664篇 |
2016年 | 3045篇 |
2015年 | 3513篇 |
2014年 | 5031篇 |
2013年 | 6800篇 |
2012年 | 10518篇 |
2011年 | 11137篇 |
2010年 | 6349篇 |
2009年 | 6044篇 |
2008年 | 10196篇 |
2007年 | 10879篇 |
2006年 | 10348篇 |
2005年 | 10598篇 |
2004年 | 10001篇 |
2003年 | 9486篇 |
2002年 | 8906篇 |
2001年 | 1484篇 |
2000年 | 1112篇 |
1999年 | 1595篇 |
1998年 | 2106篇 |
1997年 | 1644篇 |
1996年 | 1421篇 |
1995年 | 1289篇 |
1994年 | 1140篇 |
1993年 | 1113篇 |
1992年 | 774篇 |
1991年 | 783篇 |
1990年 | 609篇 |
1989年 | 595篇 |
1988年 | 557篇 |
1987年 | 570篇 |
1986年 | 507篇 |
1985年 | 534篇 |
1984年 | 636篇 |
1983年 | 565篇 |
1982年 | 759篇 |
1981年 | 701篇 |
1980年 | 602篇 |
1979年 | 364篇 |
1978年 | 375篇 |
1977年 | 403篇 |
1976年 | 342篇 |
1975年 | 293篇 |
1974年 | 249篇 |
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
991.
Kaufmann R Fölster-Holst R Höger P Thaçi D Löffler H Staab D Bräutigam M;CASMCDE-Study Group 《The Journal of allergy and clinical immunology》2004,114(5):1183-1188
BACKGROUND: Data on the efficacy of pimecrolimus cream 1% within the first days of treatment are scarce, as in previous studies, the first postbaseline assessment was performed only after 1 week. OBJECTIVE: We sought to investigate the onset of action of pimecrolimus cream 1% in infants with mild to very severe atopic eczema. METHODS: We used pimecrolimus cream 1% (n = 129) or vehicle cream (n = 66) administered in a double-blind manner for 4 weeks and then open-label pimecrolimus cream 1% for 12 weeks, with a 4-week follow-up period. RESULTS: Pimecrolimus cream 1% reduced the mean Eczema Area and Severity Index at 4 weeks by 71.5% compared with an increase of 19.4% with vehicle ( P < .001). The reduction in the Eczema Area and Severity Index with pimecrolimus cream 1% was significant at day 4 (38.5% vs 17.6% increase with vehicle). Significant improvements in caregivers' assessments of pruritus and sleep loss were observed with pimecrolimus cream 1% by day 2 ( P < .03) and day 3 ( P = .002), respectively, compared with vehicle. Responses to pimecrolimus cream 1% were sustained during the open-label phase, and pimecrolimus cream 1% was well tolerated. Symptoms of atopic eczema returned gradually after discontinuation. CONCLUSION: Pimecrolimus cream 1% was well tolerated and effective in patients with mild to very severe atopic eczema, with rapid onset of action and no disease rebound after discontinuation. 相似文献
992.
Linda M. Gerber Joseph E. Schwartz Peter L. Schnall Thomas G. Pickering 《American journal of human biology》1995,7(2):173-182
The extent to which the relationship between body fat and blood pressure either differs by sex or explains sex differences in blood pressure is examined. Estimates of the relationship of blood pressure to several measures of adiposity in men and women were obtained from a systematic review of the literature and tests of whether these relationships differ by sex were performed. Analysis of covariance (controlling for age and race) was used for both casual and ambulatory blood pressure in the Cornell Worksite Blood Pressure Study (N = 276). In general, most adiposity measures were significantly related to casual and ambulatory blood pressure in men and women. Subscapular skinfold thickness and body mass index exhibited the strongest associations. The vast majority of adiposity/blood pressure associations were not significantly different for men and women. Finally, sex differences in adiposity did not account for much of the sex difference observed in blood pressure. © 1995 Wiley-Liss, Inc. 相似文献
993.
Thomas C. Baghai Peter Zwanzger Cornelius Schüle Christo Minov Stefanie Behrens Rainer Rupprecht Hans‐Jürgen Möller Rolf Engel Brigitta Bondy 《American journal of medical genetics. Part A》2002,114(5):530-532
Growing evidence suggests that G‐proteins may be involved in pathogenesis and treatment of affective disorders. Several studies have reported altered levels and/or activities of stimulatory G‐proteins in depression. The aim of this study was to investigate whether a polymorphism in the stimulatory α subunit of G‐proteins (T/C point mutation in exon 5; ATT → ATC at codon 131) is associated with major depression or response to antidepressant treatment. Therefore, we performed a case‐control association study with 212 depressive patients and 137 healthy, unrelated controls. There was no evidence for an association between the investigated polymorphism in the Gαs gene and major depression, as well as to treatment response. The results of our study are in concordance with recently published findings which do not support the hypothesis that the gene for the stimulatory α subunit of G‐proteins is a major susceptibility factor in the pathophysiology of major depression. © 2002 Wiley‐Liss, Inc. 相似文献
994.
Turley H Wykoff CC Troup S Watson PH Gatter KC Harris AL 《The Journal of pathology》2004,203(3):808-813
DEC1, also known as SHARP-2 or Stra13, is an important molecule in embryonic differentiation and has recently been identified to be strongly inducible by hypoxia. Its distribution in normal human tissues and most tumour types is unknown. In the present study, a polyclonal antiserum to a 10-amino acid peptide from DEC1 has been raised. Using this antiserum, DEC1 was shown to be widely expressed in most normal human tissues, but usually only in a proportion of cells and typically with a nuclear localization. In tumours, expression was either augmented (the commonest pattern) or occasionally decreased. Similarly, in most normal tissues, low or absent expression was observed in endothelial cells, whereas in many tumour samples endothelium was usually strongly positive. In tumours, there was a striking pattern of staining seen in connection with areas of necrosis, with absence of DEC1 expression within a zone of morphologically viable cells immediately adjacent to the necrotic zone. This suggests that while DEC1 may be up-regulated by hypoxia in cancer, in more extreme hypoxia it may have a role in cell death. Its interrelationship with other hypoxically regulated molecules, such as the hypoxia-inducible factors or carbonic anhydrase IX, and differentiation of tumours now requires further investigation. 相似文献
995.
996.
997.
Koert P Dingemans Peter Teeling Allard C van der Wal Anton E Becker 《Cardiovascular pathology》2006,15(4):203-212
Despite the discovery in 1990 that mutations in the fibrillin-1 gene cause the Marfan syndrome, the pathogenesis of the life-threatening dissections associated with this disease is far from elucidated. Both the massive number of known fibrillin-1 mutations that result in a heterogeneous patient population and the strongly heterogeneous histology of patients' aortae presumably contribute to this lack of knowledge. We performed a detailed ultrastructural immunoelectron microscopic and histochemical analysis of the dissected media of ascending aortae of 10 patients with Marfan syndrome and compared them with those of 6 patients without Marfan syndrome and 77 individuals without known aortic disease. Relatively similar abnormalities were found in both patient groups, although they were more numerous and more diffusely spread in the patients with Marfan syndrome than in the patients without Marfan syndrome. The most conspicuous ultrastructural defects were the formation of abrupt transverse tears in thick and compact elastic lamellae and the local breaking up of smooth muscle cell-elastic lamella connections (that largely consist of microfibrils and elastic extensions, protruding from the elastic lamellae). This breaking up was characterized by a strongly reduced number of microfibrils and a severe shortening of the elastic extensions. Finally, the elastic extensions detached from the lamellae to ultimately degenerate and disappear. These changes were found mainly in the oldest group of patients with Marfan syndrome, indicating that they represented a loss of previously normally developed structures. We also compared our findings with those from a recently developed murine Marfan model (Pereira L, Lee SY, Gayraud B, Andrilopoulos K, Shapiro SD, Bunton T, Biery NJ, Dietz HC, Sakai LY, Ramirez F. Pathogenetic sequence for aneurysm revealed in mice underexpressing fibrillin-1. Proc Natl Acad Sci. U. S. A. 1999: 96: 3819-3823). Next to similarities, several striking differences existed, demonstrating that this model is not fully representative of the human Marfan syndrome. 相似文献
998.
Hamid Hossain Volker Landgraf Reinhard Weiss Marion Mann Jaleh Hayatpour Trinad Chakraborty Peter Mayser 《Medical mycology》2007,45(1):41-49
The aim of the study was the characterization of Malassezia pachydermatis and its pigment-producing subgroup using biochemical tests and RAPD. It was of interest to determine whether particular RAPD patterns could be used to indicate pigment production, as well as a close genetic relatedness to Malassezia furfur. Therefore, 210 strains of M. pachydermatis were examined for morphology, catalase and ss-glucosidase activity, lipid and carbohydrate assimilation and the tryptophan-dependent synthesis of pigments. Of these, 114 strains were subjected to RAPD analyses. A multivariate logistic regression model was applied to classify M. pachydermatis isolates regarding their pigment production by using genetic and biological parameters. Biological and RAPD findings showed a high biological and genetic diversity within the species M. pachydermatis and within pigment producers. RAPD analysis revealed 28 genotypes within 114 strains tested. Pigment producing strains could not be assigned to a common RAPD profile, but a genetic relatedness of pigment-producing M. pachydermatis with M. furfur can be assumed. A particular RAPD pattern allowed statistically significant probability of pigment production (P<0.001) and might be used as a tool to rapidly detect pigment producing M. pachydermatis, e.g. in Malassezia-associated pityriasis versicolor. The reported method is useful for identification of pigment producing M. pachydermatis isolates and has advantages over established tests. 相似文献
999.
Susan J Paxton Dianne Neumark-Sztainer Peter J Hannan Marla E Eisenberg 《Journal of clinical child and adolescent psychology》2006,35(4):539-549
This research examined whether body dissatisfaction prospectively predicted depressive mood and low self-esteem in adolescent girls and boys 5 years later. Participants were early-adolescent girls (n = 440, Time 1 M age = 12.7 years) and boys (n = 366, Time 1 M age = 12.8 years) and midadolescent girls (n = 946, Time 1 M age = 15.8 years) and boys (n = 764, Time 1 M age = 15.9 years). After controlling for Time 1 of the relevant dependent variable, ethnicity, socioeconomic status, and body mass index, Time 1 body dissatisfaction was a unique predictor of Time 2 depressive mood and low self-esteem in early-adolescent girls (depressive mood: F = 4.80, p < .05; self-esteem: F = 9.64, p < .01) and midadolescent boys (depressive mood: F = 12.27, p < .001; self-esteem: F = 9.38, p < .01) but not in early-adolescent boys or midadolescent girls. These findings are consistent with the hypothesis that body dissatisfaction is a risk factor for depressive mood and low self-esteem in both girls and boys but in different phases of adolescence. 相似文献
1000.