全文获取类型
收费全文 | 19654篇 |
免费 | 1142篇 |
国内免费 | 68篇 |
专业分类
耳鼻咽喉 | 239篇 |
儿科学 | 504篇 |
妇产科学 | 363篇 |
基础医学 | 2828篇 |
口腔科学 | 415篇 |
临床医学 | 1750篇 |
内科学 | 3642篇 |
皮肤病学 | 812篇 |
神经病学 | 2286篇 |
特种医学 | 1143篇 |
外国民族医学 | 11篇 |
外科学 | 2992篇 |
综合类 | 155篇 |
一般理论 | 5篇 |
预防医学 | 977篇 |
眼科学 | 314篇 |
药学 | 1057篇 |
中国医学 | 64篇 |
肿瘤学 | 1307篇 |
出版年
2023年 | 144篇 |
2022年 | 218篇 |
2021年 | 476篇 |
2020年 | 314篇 |
2019年 | 448篇 |
2018年 | 485篇 |
2017年 | 441篇 |
2016年 | 539篇 |
2015年 | 566篇 |
2014年 | 748篇 |
2013年 | 910篇 |
2012年 | 1442篇 |
2011年 | 1503篇 |
2010年 | 889篇 |
2009年 | 765篇 |
2008年 | 1274篇 |
2007年 | 1260篇 |
2006年 | 1205篇 |
2005年 | 1196篇 |
2004年 | 1021篇 |
2003年 | 951篇 |
2002年 | 890篇 |
2001年 | 215篇 |
2000年 | 205篇 |
1999年 | 240篇 |
1998年 | 211篇 |
1997年 | 150篇 |
1996年 | 157篇 |
1995年 | 104篇 |
1994年 | 105篇 |
1993年 | 82篇 |
1992年 | 100篇 |
1991年 | 111篇 |
1990年 | 73篇 |
1989年 | 73篇 |
1988年 | 71篇 |
1987年 | 79篇 |
1986年 | 70篇 |
1985年 | 68篇 |
1984年 | 60篇 |
1983年 | 48篇 |
1982年 | 47篇 |
1981年 | 45篇 |
1980年 | 48篇 |
1979年 | 58篇 |
1978年 | 47篇 |
1977年 | 40篇 |
1976年 | 32篇 |
1973年 | 27篇 |
1972年 | 26篇 |
排序方式: 共有10000条查询结果,搜索用时 31 毫秒
31.
Flow cytometry is a quantitative cytologic technique with demonstrated utility in the assessment of prostate cancer as well as other tumors. The authors summarize current data on its use in disease detection and diagnosis, prognostic evaluation, and monitoring of response to therapy. They also project future developments. 相似文献
32.
Immunoglobulin Gene Rearrangement in Plasma Cell Dyscrasias: Detection of Small Clonal Cell Populations in Peripheral Blood and Bone Marrow 总被引:1,自引:0,他引:1
Falko Fend Katharina Weyrer Johannes Drach Andrea Schwaiger Florian Umlauft Kurt Grü newald 《Leukemia & lymphoma》1993,10(3):223-229
The bone marrow (BM) and peripheral blood (PB) samples of 71 patients with plasma cell dyscrasias were analysed by the Southern blot technique for the presence of clonal immunoglobulin (Ig) gene rearrangements. 53% of BM samples examined were archival material such as air dried BM slides or frozen trephine biopsies. The results were related to bone marrow plasmacytosis as determined by cytology and flow cytometry, and other clinical parameters. Clonal Ig gene rearrangements were found in BM samples of 45 (83%) of 54 MM patients and in 3 of 6 patients with monoclonal gammopathy of unknown significance (MGUS). Clonal cell populations in the PB were detected in 11 (30%) of 37 examined MM patients, but in none of the patients with MGUS or solitary plasmacytoma of bone. PB involvement was associated with progressive disease. Circulating monoclonal cells were significantly associated with higher M-protein levels (p 0.05). Thus, circulating clonal precursor cells are encountered more frequently in active MM. 相似文献
33.
34.
Pneumonia is one of the leading causes of morbidity, hospitalization, and mortality in both industrialized and developing countries. In particular, pulmonary infections acquired in the community, and pneumonias arising in the hospital setting, represent a major medical and economic problem and thus a continuous challenge to health care. For the radiologist, it is important to understand that community-acquired pneumonia (CAP) and nosocomial pneumonia (NP) share a number of characteristics, but should, in many respects be regarded as separate entities. CAP and NP arise in different populations, host different spectra of causative pathogens, and pose different challenges to both the clinician and the radiologist. CAP is generally seen in outpatients, is most frequently caused by Streptococcus pneumoniae, Mycoplasma pneumoniae, Haemophilus influenzae, and Chlamydia, and its radiologic diagnosis is relatively straightforward. NP, in contrast, develops in the hospital setting, is commonly caused by gram-negative bacteria, and may generate substantial problems for the radiologist. Overall, both for CAP and NP, imaging is an integral component of the diagnosis, important for classification and differential diagnosis, and helpful for follow-up. 相似文献
35.
Expression profiling identifies the CRH/CRH-R1 system as a modulator of neurovascular gene activity.
Jan M Deussing Claudia Kühne Benno Pütz Markus Panhuysen Johannes Breu Mary P Stenzel-Poore Florian Holsboer Wolfgang Wurst 《Journal of cerebral blood flow and metabolism》2007,27(8):1476-1495
Corticotropin-releasing hormone receptor type 1 (CRH-R1)-deficient mice display reduced anxiety-like behavior, a chronic corticosterone deficit, and an impaired neuroendocrine stress response caused by disruption of the hypothalamic-pituitary-adrenocortical (HPA) axis. The molecular substrates and pathways of CRH/CRH-R1-dependent signaling mechanisms underlying the behavioral phenotype as well as the consequences of lifelong glucocorticoid deficit remain largely obscure. To dissect involved neuronal circuitries, we performed comparative expression profiling of brains of CRH-R1 mutant and wild-type mice using our custom made MPIP (Max Planck Institute of Psychiatry) 17k cDNA microarray. Microarray analysis yielded 107 genes showing altered expression levels when comparing CRH-R1 knockout mice with wild-type littermates. A significant proportion of differentially expressed genes was related to control of HPA and hypothalamic-pituitary-thyroid (HPT) axes reflecting not only the disturbance of the HPA axis in CRH-R1 mutant mice but also the interplay of both neuroendocrine systems. The spatial analysis of regulated genes revealed a prevalence for genes expressed in the cerebral microvasculature. This phenotype was confirmed by the successful cross-validation of regulated genes in CRH overexpressing mice. Analysis of the cerebral vasculature of CRH-R1 mutant and CRH overexpressing mice revealed alterations of functional rather than structural properties. A direct role of the CRH/CRH-R1 system was supported by demonstrating Crhr1 expression in the adult murine cerebral vasculature. In conclusion, these data suggest a novel, previously unknown role of the CRH/CRH-R1 system in modulating neurovascular gene expression and function. 相似文献
36.
Johannes Bjornsson John R. Goellner David Eugene Williams Mary V. Scheiber 《Journal of cancer research and clinical oncology》1986,111(3):289-290
Preoperative cytologic examinations were performed on bronchial material from 92 patients with postsurgical (pathologic) stage I (American Joint Committee) adenocarcinoma of the lung. All patients were followed up for at least 5 years or until death; thus, cases of adenocarcinoma metastatic to the lungs were virtually excluded. Only 22 patients (24%) had abnormal preoperative cytologic findings. This low cytologic sensitivity is ascribed to the small size and peripheral location of the tumors. Large lesions of high histologic grades were more likely to have positive preoperative cytologic findings than small, well-differentiated ones. 相似文献
37.
38.
39.
A. D. Kirk W. S. Cherikh M. Ring G. Burke D. Kaufman S. J. Knechtle S. Potdar R. Shapiro V. R. Dharnidharka H. M. Kauffman 《American journal of transplantation》2007,7(11):2619-2625
Transplant patients are at the risk for posttransplant lymphoproliferative disease (PTLD), a virally-driven malignancy. Induction with the depleting antibody preparations Thymoglobulin and OKT3 is associated with PTLD suggesting that the T-cell depletion increases PTLD risk. We therefore studied 59 560 kidney recipients from the Organ Procurement and Transplantation Network/United Network for Organ Sharing (OPTN/UNOS) database for a relationship between induction agent use and PTLD. Two agents with comparable T-cell depletional effects, alemtuzumab and Thymoglobulin, were compared to nondepletional induction agents or no induction. The overall incidence of PTLD was 0.46% and differed significantly by induction strategy (p < 0.01): without induction (0.43%), basiliximab (0.38%), daclizumab (0.33%), Thymoglobulin (0.67%) and alemtuzumab (0.37%). Thymoglobulin was associated with significantly increased PTLD risk (p = 0.0025), but alemtuzumab (p = 0.74), basiliximab (p = 0.33) and daclizumab, which trended toward a protective effect (p = 0.06), were not. Alemtuzumab and Thymoglobulin treated patients did not differ in any established parameter affecting PTLD risk although alemtuzumab is known to have a more pronounced B-cell depleting effect. Interestingly, maintenance therapy with an mTOR inhibitor was strongly associated with PTLD (0.71%, p < 0.0001). Thus, depletional induction is not an independent risk factor for PTLD. Rather, maintenance drug selection or perhaps the balance between B- and T-cell depletion may be more relevant determinants of PTLD risk. 相似文献
40.
Stefan Beckers Michael Fries Johannes Bickenbach Matthias Derwall Ralf Kuhlen Rolf Rossaint 《Critical care (London, England)》2004,9(2):R110