首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   729篇
  免费   33篇
  国内免费   1篇
耳鼻咽喉   7篇
儿科学   2篇
妇产科学   10篇
基础医学   80篇
口腔科学   16篇
临床医学   72篇
内科学   307篇
皮肤病学   8篇
神经病学   31篇
特种医学   33篇
外科学   62篇
预防医学   30篇
眼科学   6篇
药学   59篇
中国医学   4篇
肿瘤学   36篇
  2023年   5篇
  2022年   3篇
  2021年   19篇
  2020年   11篇
  2019年   9篇
  2018年   7篇
  2017年   7篇
  2016年   11篇
  2015年   7篇
  2014年   14篇
  2013年   25篇
  2012年   54篇
  2011年   37篇
  2010年   31篇
  2009年   19篇
  2008年   60篇
  2007年   48篇
  2006年   45篇
  2005年   35篇
  2004年   32篇
  2003年   37篇
  2002年   33篇
  2001年   23篇
  2000年   22篇
  1999年   17篇
  1998年   11篇
  1997年   5篇
  1996年   5篇
  1995年   3篇
  1994年   3篇
  1993年   1篇
  1992年   22篇
  1991年   12篇
  1990年   14篇
  1989年   10篇
  1988年   9篇
  1987年   12篇
  1986年   8篇
  1985年   10篇
  1984年   8篇
  1983年   1篇
  1982年   4篇
  1980年   1篇
  1979年   6篇
  1978年   2篇
  1977年   2篇
  1964年   1篇
  1962年   2篇
排序方式: 共有763条查询结果,搜索用时 16 毫秒
21.
In vitro and in vivo antidermatophyte activities of NND-502, a new imidazole antimycotic agent, were compared with those of two existing antifungal agents, lanoconazole and terbinafine. NND-502 exhibited strong in vitro antifungal activity against Trichophyton spp.; its MIC was 1 to 4 times lower than that of lanoconazole or terbinafine. In an in vivo study with a guinea pig model of tinea pedis, 7-day topical treatment with a 0.5% solution of NND-502 (dissolved in polyethylene glycol 400) was more effective than that with a 0.5% solution of either lanoconazole or terbinafine for eradicating fungi from the infected feet. When the duration of treatment was shortened to 3 days, a topical 1% solution of NND-502 achieved a complete mycological cure, while topical 1% solutions of lanoconazole and terbinafine did not.  相似文献   
22.
The therapeutic efficacy of short-term treatment with a 1% cream of lanoconazole, a new imidazole antimycotic agent, in comparison with that of a 1% cream of terbinafine was evaluated in the guinea pig model of tinea pedis. Each agent was topically applied once a day for 3 or 7 consecutive days, starting on day 10 postinfection, and a culture study was conducted on day 5 after the last treatment with each agent. The 1% cream of lanoconazole was as highly effective as the 1% cream of terbinafine in terms of eradicating the fungi from the infected feet.  相似文献   
23.
In experimental autoimmune myocarditis (EAM) there is a characteristic initial focal inflammatory response in the myocardium, induced mainly by CD4(+) T cells and macrophages, which leads to massive myocardial damage. Macrophage inflammatory protein-1alpha (MIP-1alpha) induces chemotaxis in lymphocytes, eosinophils, basophils, and macrophages. We assessed the potential role of MIP-1alpha in the pathogenesis of EAM in rats immunized with porcine myosin. Following immunization, the levels of MIP-1alpha mRNA in EAM showed an increase on Day 11 and peaked on Day 17. MIP-1alpha-positive cells were predominantly immunoreactive to OX6 antibody (dendritic cells) and ED2 antibody (resident macrophages) by Day 14. Marked cellular infiltration was seen on Day 17 with the major population of MIP-1alpha-positive cells also positive for ED1 (inflammatory macrophages). We then examined the association of MIP-1alpha with the development of myocardial inflammation. Rats were divided into three groups: Group A consisted of EAM rats (n = 10); Group B consisted of EAM rats treated with anti-MIP-1alpha (1 mg/kg) on Days 11, 13, and 15, before the onset of initial inflammation (n = 5); and Group C consisted of EAM rats treated with anti-MIP-1alpha from the start of the initial inflammation on Days 14, 16, and 18 (n = 5). Rats were euthanized on Day 21 and three transverse sections of the heart were prepared to determine the percentage of the area affected by inflammatory lesions. This area of inflammation was significantly smaller in Group B (27 +/- 4%) than in Groups A (51 +/- 6%) or C (50 +/- 6%) (p < 0.01), indicating that the administration of antibody before the initiation of inflammation, in part, will inhibit myocardial inflammation. These data suggest that MIP-1alpha may play an important role in the recruitment of inflammatory cells in the early stages of EAM.  相似文献   
24.
BACKGROUND: It is uncertain whether atherosclerosis is accelerated in premenopausal and postmenopausal patients with long-term well-controlled systemic lupus erythematosus (SLE). METHODS: We measured the intima-media thickness (IMT) of the carotid arteries and the cardio-ankle vascular index (CAVI) in 39 women with SLE and in age- and sex-matched controls. RESULTS: In the premenopausal state, carotid plaque was detected only in SLE patients (36%). In the postmenopausal state, the maximum IMT was about 2-fold greater in SLE patients than in control subjects (1.3+/-0.7 vs. 0.7+/-0.2 mm, p<0.001). CAVI was higher in both the premenopausal and postmenopausal SLE patients. The serum amyloid A protein (SAA) was higher in SLE patients in the premenopausal state (p=0.025), while remnant like particle-cholesterol (RLP-C), the homeostasis model assessment of insulin resistance (HOMA-IR), and SAA were significantly increased in postmenopausal SLE patients (p=0.001, p<0.001 and p<0.05, respectively). Multiple regression analysis revealed that the maximum IMT was associated with cumulative PSL dosage (p=0.027) and SAA (p=0.074) in the premenopausal SLE patients, and with HOMA-IR (p<0.001) in the postmenopausal SLE patients. CONCLUSION: Atherosclerosis is accelerated in long-term well-controlled SLE. More attention should be given to subclinical inflammation and insulin resistance in the management of SLE patients.  相似文献   
25.
BACKGROUND: T-cell-mediated myocardial damage is known to be involved in acute myocarditis and dilated cardiomyopathy. Recently, we found that tumor necrosis factor (TNF) ligand superfamily costimulatory molecules, especially 4-1BBL, played an important role in the myocardial damage of murine acute viral myocarditis. METHODS AND RESULTS: To investigate the roles for CD27L, CD30L, OX40L and 4-1BBL, which belong to TNF ligand superfamily, in the development of acute myocarditis and dilated cardiomyopathy, we analyzed the expression of these antigens in the myocardial tissues of patients with acute myocarditis and dilated cardiomyopathy. We also examined expression of the receptors for these molecules, CD27, CD30, OX40 and 4-1BB, which belong to TNF receptor superfamily, on the infiltrating cells. Strong expression of CD27L, CD30L and 4-1BBL and weak to moderate expression of OX40L was found in the cardiac myocytes of patients with acute myocarditis. Moderate expression of CD27L, CD30L and 4-1BBL and weak expression of OX40L was found on the cardiac myocytes of patients with dilated cardiomyopathy. Most of the infiltrating cells expressed CD27, CD30 and 4-1BB and a part of the infiltrating cells expressed OX40. CONCLUSIONS: Our findings suggest that expression of TNF ligand superfamily costimulatory molecules on cardiac myocytes may play a role in the cell-mediated myocardial damage in patients with acute myocarditis and dilated cardiomyopathy as in murine viral myocarditis.  相似文献   
26.
Genetic analysis on formalin‐fixed paraffin‐embedded (FFPE) tissue specimens has become a mainstream method, from conventional direct sequencing to comprehensive analysis using next‐generation sequencing (NGS). In this study, we evaluated the quality of DNA and RNA extracted from FFPE sections, derived from surgical specimens of different tumor types. Electrophoresis was performed using a 4200 TapeStation to evaluate DNA and RNA fragmentation. DNA Ct values were higher and significantly increased over a period of 4 years compared with those from cell lines or frozen tissues. The RNA integrity number equivalent (RIN) ranged from 1 to 4.1 and DV200 ranged from 7.3 to 81%. Twelve of the 108 cases were analyzed by NGS using the AmpliSeq Cancer HotSpot Panel v2 on a Miniseq system. A sufficient number of reads and coverage were obtained in all cases. Our results revealed that NGS analysis was sufficient for FFPE‐derived DNA within 4 years of preservation. Conversely, approximately 20% of the RNA derived from FFPE within 4 years from the collection could be inappropriate for gene analysis based on RIN and DV200. It was suggested that FFPE would be adequate for genetic analysis, although it is desirable to store frozen specimens for the tumor tissues to be subjected to genetic analysis.  相似文献   
27.
The pathophysiologic basis for the exuberant intracellular growth of Mycobacterium avium complex (MAC) in AIDS patients is unclear but may relate to altered expression of modulatory cytokines. Interleukin (IL)-1, IL-6, and TNF- expression by monocytes from AIDS patients and healthy subjects (HS) stimulated with isogeneic MAC strains (SmT, smooth-transparent, virulent; SmD, smooth-domed, avirulent) was examined. Spontaneous cytokine production was not observed in patients with AIDS. MAC strains induced less IL-1 and IL-1 release in AIDS patients than HS (P < 0.05). The ratio of cell-associated to supernatant IL-1 also was increased in AIDS patients (P = 0.03). IL-1 mRNA expression paralleled protein release in either group of subjects. In both HS and AIDS patients, stimulation with SmD induced more IL-1 and TNF- release by monocytes compared to SmT. In AIDS patients, SmD also induced greater IL-6 release than SmT (P < 0.01). Alterations in monocyte expression and compartmentalization of the regulatory cytokines IL-1 and IL-6 may enhance bacterial replication and contribute to the patho-genesis of MAC infection in AIDS.  相似文献   
28.
Recent evidences suggest that the extracts of plant products are able to modulate innate immune responses. A saponin GL and a chalcone ILG are representative components of Glycyrrhiza uralensis, which attenuate inflammatory responses mediated by TLRs. Here, we show that GL and ILG suppress different steps of the LPS sensor TLR4/MD-2 complex signaling at the receptor level. Extract of G. uralensis suppressed IL-6 and TNF-α production induced by lipid A moiety of LPS in RAW264.7 cells. Among various G. uralensis-related components of saponins and flavanones/chalcones, GL and ILG could suppress IL-6 production induced by lipid A in dose-dependent manners in RAW264.7 cells. Furthermore, elevation of plasma TNF-α in LPS-injected mice was attenuated by passive administration of GL or ILG. GL and ILG inhibited lipid A-induced NF-κB activation in Ba/F3 cells expressing TLR4/MD-2 and CD14 and BMMs. These components also inhibited activation of MAPKs, including JNK, p38, and ERK in BMMs. In addition, GL and ILG inhibited NF-κB activation and IL-6 production induced by paclitaxel, a nonbacterial TLR4 ligand. Interestingly, GL attenuated the formation of the LPS-TLR4/MD-2 complexes, resulting in inhibition of homodimerization of TLR4. Although ILG did not affect LPS binding to TLR4/MD-2, it could inhibit LPS-induced TLR4 homodimerization. These results imply that GL and ILG modulate the TLR4/MD-2 complex at the receptor level, leading to suppress LPS-induced activation of signaling cascades and cytokine production, but their effects are exerted at different steps of TLR4/MD-2 signaling.  相似文献   
29.
Caveolins—caveolin‐1, ‐2, ‐3 (Cav1, 2, 3)—are major components of caveolae, which have diverse functions. Our recent study on the temporomandibular joint (TMJ) revealed expressions of Cav1 and muscle‐specific Cav3 in some synovial fibroblast‐like type B cells with well‐developed caveolae. However, the involvement of Cav3 expression in the differentiation and maturation of type B cells remains unclear. The present study therefore examined the chronological alterations in the localization of Cav3 in the synovial lining cells of the rat TMJ during postnatal development by immunocytochemical techniques. Observations showed immature type B cells possessed a few caveolae with Cav1 but lacked Cav3 protein at postnatal day 5 (P5). At P14, Cav3‐immunopositive type B cells first appeared in the synovial lining layer. They increased in number and immunointensity from P14 to P21 as occlusion became active. In immunoelectron microscopy and double immunolabeling with heat shock protein 25 (Hsp25) and Cav3, coexpressed type B cells developed rough endoplasmic reticulum and numerous caveolae, while the Cav3‐immunonegative type B cell with Hsp25 immunoreaction possessed few of these. Results suggest that Cav3 expression, which is closely related to added functional stimuli, reflects the differentiation of the type B synoviocytes. Anat Rec, 291:233–241, 2008. © 2008 Wiley‐Liss, Inc.  相似文献   
30.
The immunological aspects of autoimmune myocarditis are difficult to understand because of the existence of many infectious agents and animal models suggesting different mechanisms in autoimmune myocarditis. To overcome these difficulties, two strains of mice, C3H/HeN and C3H/HeJ, showing different immune responses to mycobacteria, were immunized with myosin mixed with BCG. The C3H/HeN mice with a wild-type Toll-like receptor 4 (TLR4) showed severe myocarditis, whereas the C3H/HeJ mice with nonfunctional mutated TLR4 did not. CD4(+) cells from both strains of mice exhibited appreciable proliferative responses following myosin stimulation; however, the cytokines from these cells differed between these two strains. The C3H/HeN mice showed T helper (Th)1-type cytokine responses, whereas the expressions of mRNA in C3H/HeJ mice were Th2-type cytokine. When both of these strains of immunized mice were inoculated with a plasmid encoding cDNA of interleukin (IL)-4 or agonistic IL-4, the development of myocarditis was inhibited in C3H/HeN mice. Moreover, C3H/HeJ mice, in which development of myocarditis was not induced by immunization of myosin mixed with BCG, showed myocarditis after injection of IL-4 antagonistic mutant DNA for the induction of Th1-type immune responses. The results suggested that the induction of autoimmune myocarditis by myosin is affected by Th1-type immune responses.  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号