全文获取类型
收费全文 | 7259篇 |
免费 | 312篇 |
国内免费 | 8篇 |
专业分类
耳鼻咽喉 | 188篇 |
儿科学 | 210篇 |
妇产科学 | 211篇 |
基础医学 | 1280篇 |
口腔科学 | 136篇 |
临床医学 | 630篇 |
内科学 | 1162篇 |
皮肤病学 | 195篇 |
神经病学 | 699篇 |
特种医学 | 426篇 |
外国民族医学 | 3篇 |
外科学 | 1033篇 |
综合类 | 32篇 |
一般理论 | 2篇 |
预防医学 | 364篇 |
眼科学 | 231篇 |
药学 | 404篇 |
中国医学 | 75篇 |
肿瘤学 | 298篇 |
出版年
2022年 | 44篇 |
2021年 | 72篇 |
2020年 | 45篇 |
2019年 | 86篇 |
2018年 | 91篇 |
2017年 | 80篇 |
2016年 | 100篇 |
2015年 | 123篇 |
2014年 | 152篇 |
2013年 | 246篇 |
2012年 | 347篇 |
2011年 | 360篇 |
2010年 | 241篇 |
2009年 | 231篇 |
2008年 | 325篇 |
2007年 | 311篇 |
2006年 | 328篇 |
2005年 | 297篇 |
2004年 | 313篇 |
2003年 | 311篇 |
2002年 | 274篇 |
2001年 | 137篇 |
2000年 | 127篇 |
1999年 | 139篇 |
1998年 | 91篇 |
1997年 | 86篇 |
1996年 | 56篇 |
1995年 | 64篇 |
1994年 | 45篇 |
1993年 | 49篇 |
1992年 | 88篇 |
1991年 | 76篇 |
1990年 | 72篇 |
1989年 | 61篇 |
1988年 | 81篇 |
1987年 | 78篇 |
1986年 | 52篇 |
1985年 | 74篇 |
1984年 | 45篇 |
1983年 | 49篇 |
1979年 | 45篇 |
1978年 | 39篇 |
1977年 | 42篇 |
1975年 | 46篇 |
1971年 | 40篇 |
1966年 | 36篇 |
1933年 | 36篇 |
1930年 | 38篇 |
1929年 | 45篇 |
1928年 | 43篇 |
排序方式: 共有7579条查询结果,搜索用时 31 毫秒
61.
Riedl M Czech T Slootweg J Czernin S Hainfellner JA Schima W Vierhapper H Luger A 《Endocrine pathology》1995,6(2):159-166
This report describes a case of lymphocytic hypophysitis in a 63-year-old man who presented with symptoms of a pituitary mass
lesion associated with hypothyroidism and hypogonadism. Postoperative endocrinological testing demonstrated gonadotropic,
thyrotropic, and corticotropic hypopituitarism, and the patient was commenced on replacement therapy with hydrocortisone and
levothyroxine. Histological examination of the pituitary tissue obtained by transsphenoidal surgery revealed lymphocytic hypophysitis
without evidence of a pituitary adenoma. The vast majority of patients with lymphocytic hypophysitis are women particularly
during pregnancy and the puerperium. Until recently only four men were reported in the literature. The pathogenesis of lymphocytic
hypophysitis is uncertain but autoimmune mechanisms are possibly involved. 相似文献
62.
Ehrlich ascites cells activate the alternative pathway of the human complement system 总被引:1,自引:0,他引:1
Incubation of Ehrlich ascites cells with normal or C1q or C2 deficient human sera results in killing of the cells. Killing occurred also in the absence of free Ca++, which supported by the fact that factor B and C3 were cleaved, leads to the conclusion that the alternative pathway of the complement system is activated on the surface of the Ehrlich ascites cells. 相似文献
63.
Interleukin-11 expression: its significance in eutopic and ectopic human implantation 总被引:5,自引:0,他引:5
von Rango U Alfer J Kertschanska S Kemp B Müller-Newen G Heinrich PC Beier HM Classen-Linke I 《Molecular human reproduction》2004,10(11):783-792
Embryo implantation and subsequent decidualization, trophoblast invasion and formation of a functional placenta are crucial for establishment and maintenance of pregnancy. Interleukin-11 signalling has been shown to be obligatory for adequate decidualization and trophoblast invasion in mice. Defects in IL-11 signalling in mice result in trophoblast over-invasion and fetal loss. The pathological situation of human tubal pregnancy resembles that of IL-11Ralpha(-/-) mice concerning these symptoms. As our interest is focused on the human early pregnancy, we compared IL-11 expression at the implantation site of ectopic tubal pregnancy (EP) to 1st and 2nd trimester of normal intrauterine pregnancies (IP), and to the normal cycling endometrium. The mRNA expression of IL-11 and IL-11Ralpha was analysed by semiquantitative RT-PCR. Protein expression was detected by western blotting and immunohistochemistry. IL-11Ralpha is expressed constitutively in all tissue specimens analysed. IL-11 is expressed predominantly during follicular and early luteal phase of the menstrual cycle. In IP, IL-11 expression peaks during the 1st trimester and declines from the beginning of the 2nd trimester onwards. In tubal abortions, IL-11 expression is reduced in comparison to vital EP and IP. Cultured primary endometrial and decidual epithelial cells were analysed for hormonal regulation of IL-11 by enzyme-linked immunosorbent assay and RT-PCR. IL-11 is up-regulated by estrogen and down-regulated by progesterone. Overall, our results indicate that in humans, IL-11 signalling is significantly involved in regulation of trophoblast invasion. In the case of tubal abortion, inadequate IL-11 signalling may therefore result in dysregulation of trophoblast invasion. 相似文献
64.
Nissum M Preuss D Harig A Lieberwirth U Betz C Neumann S Deravanessian E Bock M Wehmeier L Bonk T 《Psychiatric genetics》2002,12(2):109-117
Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) has become a powerful and widespread analytical tool in all fields of life science. Compared with other techniques, its high accuracy and sensitivity makes it a superior method, especially for the analysis of nucleic acids. Recent problems in the analysis of nucleic acids by MALDI-TOF MS can be solved using an automated MALDI-compatible sample-preparation system. Together with the reliable minisequencing assay, high-throughput genotyping of single nucleotide polymorphisms by MALDI-TOF MS is able to become a routine method in research, clinical genetics and diagnostics. 相似文献
65.
Characterization of a population of small macrophages in induced sputum of patients with chronic obstructive pulmonary disease and healthy volunteers 下载免费PDF全文
Frankenberger M Menzel M Betz R Kassner G Weber N Kohlhäufl M Häussinger K Ziegler-Heitbrock L 《Clinical and experimental immunology》2004,138(3):507-516
The inflammatory process in chronic obstructive pulmonary disease (COPD) is active mainly in the airways, but little is known about the properties of the inflammatory cells in this compartment. We have studied leucocytes in induced sputum of COPD patients compared to controls in order to uncover what types of macrophages might be involved in the disease. Sputum induction was performed by inhalation of nebulized sodium chloride solution. Leucocytes were isolated and stained with specific monoclonal antibodies for analysis in flow cytometry. Flow cytometry analysis revealed that a major portion of CD14+ macrophages in COPD has lower forward scatter, i.e. they are small macrophages. While in control donors these small macrophages accounted for 6.9% of all macrophages, the percentage of these cells in COPD was 45.7%. CD14 and HLA-DR expression was high on these small sputum macrophages while the large sputum macrophages expressed only low levels of these surface molecules, both in control donors and COPD patients. Small sputum macrophages of both control donors and COPD patients showed higher levels of constitutive tumour necrosis factor (TNF) compared to the large macrophages. TNF was inducible by lipopolysaccharide (LPS) preferentially in the small sputum macrophages in the control donors but there was no further induction in COPD patients. These data show that the small sputum macrophages are a major macrophage population in COPD and that these cells exhibit features of highly active inflammatory cells and may therefore be instrumental in airway inflammation in COPD. 相似文献
66.
67.
Gehring U Brunekreef B Fahlbusch B Wichmann HE Heinrich J;INGA Study Group 《Allergy》2005,60(8):1079-1082
BACKGROUND: Moisture is vitally important for house dust mites and they cannot survive in cold or hot-dry climates. AIMS OF THE STUDY: To investigate the influence of two extraordinarily cold and dry winters in 1995/1996 and 1996/1997 on house dust mite levels in German homes. METHODS: Dust samples were collected between June 1995 and December 2001 on the mattresses of 655 adults and 454 schoolchildren living in five different areas of Germany. We compared house dust mite allergen Dermatophagoides pteronyssinus (Der p 1) levels before and during the winters of 1995/1996 and 1996/1997 with levels after these winters. RESULTS: D. pteronyssinus (Der p 1) levels in samples taken after the cold winters of 1995/1996 and 1996/1997 were approximately two times lower than Der p 1 levels in dust samples collected before or during these respective winters (Geometric means: Erfurt 89 vs 33 ng/g; Hamburg 333 vs 219 ng/g; Bitterfeld, Hettstedt, and Zerbst 296 vs 180 ng/g). Except for Hamburg, the decrease in Der p 1 levels was statistically significant. D. pteronyssinus levels measured in dust samples collected in 2001 (i.e. 3 years after the two cold winters) show a statistically non-significant increase (Geometric means: Erfurt 33 vs 39 ng/g; Hamburg 219 vs 317 ng/g), suggesting that it may take a long time for mite allergen levels to increase again after a sudden decrease. CONCLUSION: We conclude that Der p 1 levels in German mattress dust samples have been approximately reduced by a factor of three to four by the two consecutive cold winters of 1995/1996 and 1996/1997. 相似文献
68.
Efficacy and safety of imatinib mesylate in advanced gastrointestinal stromal tumors 总被引:1,自引:0,他引:1
69.
Repeated measurements of body composition and subcutaneous fat distribution were obtained in female gymnasts to test the hypothesis of a selective response from localized fat deposits to intense physical training. Repeated measurements were obtained on the members of three nationally ranked collegiate gymnastic teams: at the beginning and peak of the training season. The highest ranked team was measured a third time, three weeks after the end of the competitive season. Body composition was estimated using anthropometry and bioelectric impedance; subcutaneous fat thickness was measured using skinfold calipers and ultrasound images of adipose tissue thickness (ATT). The mean difference between baseline and peak measurements were statistically significant (P ? .05) for the triceps and suprailiac skinfolds, and for the adipose tissue thickness at the suprailiac and hypogastric sites. There were no significant changes in weight, percentage of body fat, circumferences, or subcutaneous fat thickness at the subscapular, calf or medial thigh sites. In the team with three sets of measurements, only the triceps skinfold and the suprailiac ATT showed a statistically significant effect of training. © 1993 Wiley-Liss, Inc. 相似文献
70.