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   5161篇
  免费   302篇
  国内免费   24篇
耳鼻咽喉   63篇
儿科学   139篇
妇产科学   118篇
基础医学   690篇
口腔科学   596篇
临床医学   420篇
内科学   1087篇
皮肤病学   152篇
神经病学   317篇
特种医学   213篇
外科学   527篇
综合类   43篇
一般理论   1篇
预防医学   559篇
眼科学   95篇
药学   290篇
中国医学   39篇
肿瘤学   138篇
  2023年   47篇
  2022年   110篇
  2021年   192篇
  2020年   139篇
  2019年   134篇
  2018年   195篇
  2017年   122篇
  2016年   150篇
  2015年   177篇
  2014年   239篇
  2013年   299篇
  2012年   433篇
  2011年   425篇
  2010年   206篇
  2009年   210篇
  2008年   305篇
  2007年   296篇
  2006年   266篇
  2005年   239篇
  2004年   164篇
  2003年   146篇
  2002年   145篇
  2001年   109篇
  2000年   86篇
  1999年   75篇
  1998年   57篇
  1997年   39篇
  1996年   28篇
  1995年   29篇
  1994年   28篇
  1993年   29篇
  1992年   18篇
  1991年   28篇
  1990年   23篇
  1989年   27篇
  1988年   19篇
  1987年   17篇
  1986年   28篇
  1985年   13篇
  1984年   14篇
  1983年   12篇
  1982年   11篇
  1981年   15篇
  1980年   15篇
  1977年   11篇
  1976年   13篇
  1973年   10篇
  1971年   9篇
  1970年   16篇
  1969年   12篇
排序方式: 共有5487条查询结果,搜索用时 31 毫秒
101.
Haem oxygenase (HO) and its product carbon monoxide (CO) are associated with cytoprotection and maintenance of homeostasis in several different organs and tissues. This review focuses upon the role of exogenous and endogenous CO (via HO activity and expression) in various CNS pathologies, based upon data from experimental models, as well as from some clinical data on human patients. The pathophysiological conditions reviewed are cerebral ischaemia, chronic neurodegenerative diseases (Alzheimer''s and Parkinson''s diseases), multiple sclerosis and pain. Among these pathophysiological conditions, a variety of cellular mechanisms and processes are considered, namely cytoprotection, cell death, inflammation, cell metabolism, cellular redox responses and vasomodulation, as well as the different targeted neural cells. Finally, novel potential methods and strategies for delivering exogenous CO as a drug are discussed, particularly approaches based upon CO-releasing molecules, their limitations and challenges. The diagnostic and prognostic value of HO expression in clinical use for brain pathologies is also addressed.

Linked Articles

This article is part of a themed section on Pharmacology of the Gasotransmitters. To view the other articles in this section visit http://dx.doi.org/10.1111/bph.2015.172.issue-6  相似文献   
102.
103.
SETTING: Three mycobacteria reference laboratories in the south-eastern part of Brazil. OBJECTIVE: To evaluate the automated Mycobacteria Growth Indicator Tube (MGIT) for drug susceptibility testing of Mycobacterium tuberculosis. DESIGN: Performance of the automated BACTEC MGIT 960 (M960) system for testing M. tuberculosis susceptibility to streptomycin (SM), isoniazid (INH), rifampicin (RMP) and ethambutol (EMB) was evaluated with 95 clinical isolates and compared to the results of the radiometric BACTEC 460TB (B460) system, the proportion method (PM), and the resistance ratio method (RRM). Judicial susceptibility profiles of 88 isolates were defined based on two or more concordant results among B460, PM and RRM, and used as a reference for comparison with M960 results. RESULTS: Agreement rates between M960 and conventional methods were 95.2% with B460, 96.6% with the PM and 93.4% with the RRM. The lowest agreement rates were obtained for SM with the RRM and for EMB with B460. When comparing M960 with judicial susceptibility profiles, the agreement rate was 97.9%. The agreement rates obtained for INH and RMP were 99.2% and for SM and EMB they were 96.2% and 96.9%, respectively. The mean time to reporting the M960 results was 6.9 days. CONCLUSION: M960 offers great improvements when compared to the proportion and resistance ratio methods and would benefit patient treatment.  相似文献   
104.
SETTING: Mycobacteria growth in media with the addition of inhibitory substances has been used in species identification. Growth of the Mycobacterium tuberculosis complex (MTC) is inhibited by rho-nitrobenzoic acid (PNB), whereas non-tuberculous mycobacteria (NTM) are resistant. OBJECTIVE: To develop a rapid PNB test using the automated BACTEC MGIT960 system and to evaluate its usefulness in the screening of mycobacterial isolates. DESIGN: PNB tests were performed in 93 MTC strains and 61 NTM strains from the Instituto Adolfo Lutz Culture Collection. PNB was added to L?wenstein-Jensen (LJ) medium and to BACTEC MGIT960 medium. RESULTS: The MTC strains were all PNB-susceptible, confirming the original identification. Among 10 NTM species, all were found to be resistant to PNB, except for one strain of M. kansasii and another of M. marinum. The median time to obtain presumptive identification of MTC by inhibition test in the BACTEC MGIT960 system was 6.3 days and for NTM it was 2.5 days. The presumptive identification of MTC in LJ was mostly obtained after day 20. CONCLUSION: The key finding of this analysis was the possibility of combining the traditionally accepted method proposed by Tsukamura and Tsukamura in 1964 with the modern, safe and rapid BACTEC MGIT960 methodology.  相似文献   
105.
Necrotizing fasciitis is a rare soft tissue infection and a life-threatening emergency, often fatal. Its incidence and management are described plentifully in the medical literature regarding the most common anatomical sites involved like the abdomen, lower and upper limbs, and perineum. However, available data and case reports of chest wall necrotizing fasciitis after thoracic procedures are scarce, mainly after major cardiac operations. We report and discuss a case of necrotizing fasciitis of the chest wall occurring in the immediate postoperative period of a cardiac procedure, and include a brief review of the concepts, pathophysiology, and treatment reported in the medical literature. We emphasize the need for early diagnosis and urgent and effective surgical debridement. Of importance is the fact that we have not found any references in the literature to cases similar or equal to the one we describe here, which occurred in the postoperative period of a cardiac procedure.  相似文献   
106.
OBJECTIVES: To compare the short-term prognosis of patients with severe acute rheumatic carditis when treated with an intravenous pulse of methylprednisolone in comparison with conventional treatment using oral prednisone. METHODS: We designed a randomized clinical trial in the setting of a university general hospital in Brazil. We randomly allocated 18 patients with the diagnosis of severe acute rheumatic carditis and congestive heart failure to receive an intravenous pulse as opposed to oral prednisolone. Methylprednisolone was administered in a dose of 1 g intravenously for 3 consecutive days in the first and second weeks, for two days in the third, and one day in the fourth week. Prednisone was administered in a dose of 1.5 mg/kg/day over the period of 4 weeks. RESULTS: The mean age of the patients was 11.1 +/- 3.7 years, with a median of 12 years. Patients on oral treatment showed a more pronounced decrease in the heart rate, sedimentation rate, and in the titres of C-reactive protein than those receiving intravenous therapy. At the end of treatment, a mild decrease in the left ventricular end-systolic dimension was found in those having oral treatment, compared to an increase in the group having intravenous treatment (p = 0.036). The ejection fraction showed a median increase of 5% in those undergoing oral treatment, and a median decrease of 6% in the group with intravenous therapy (p = 0.009). There were 5 therapeutic failures in those receiving intravenous therapy (56%), including 1 death. Therapeutic failures were not observed in those treated orally (p = 0.03). CONCLUSION: Intravenous treatment of methylprednisolone, as a single anti-inflammatory agent, was inferior to conventional treatment with oral prednisone in the control of severe rheumatic carditis.  相似文献   
107.
Here, we evaluated a previously established peptide nucleic acid-fluorescence in situ hybridization (PNA-FISH) method as a new diagnostic test for Helicobacter pylori clarithromycin resistance detection in paraffin-embedded gastric biopsy specimens. Both a retrospective study and a prospective cohort study were conducted to evaluate the specificity and sensitivity of a PNA-FISH method to determine H. pylori clarithromycin resistance. In the retrospective study (n = 30 patients), full agreement between PNA-FISH and PCR-sequencing was observed. Compared to the reference method (culture followed by Etest), the specificity and sensitivity of PNA-FISH were 90.9% (95% confidence interval [CI], 57.1% to 99.5%) and 84.2% (95% CI, 59.5% to 95.8%), respectively. In the prospective cohort (n = 93 patients), 21 cases were positive by culture. For the patients harboring clarithromycin-resistant H. pylori, the method showed sensitivity of 80.0% (95% CI, 29.9% to 98.9%) and specificity of 93.8% (95% CI, 67.7% to 99.7%). These values likely represent underestimations, as some of the discrepant results corresponded to patients infected by more than one strain. PNA-FISH appears to be a simple, quick, and accurate method for detecting H. pylori clarithromycin resistance in paraffin-embedded biopsy specimens. It is also the only one of the methods assessed here that allows direct and specific visualization of this microorganism within the biopsy specimens, a characteristic that allowed the observation that cells of different H. pylori strains can subsist in very close proximity in the stomach.  相似文献   
108.
The aim of this pilot study was to assess the release of locally delivered doxycycline by poly (l-lactide-co-glycolide) (PLGA) microspheres in the periodontal pocket of patients with chronic periodontitis, treated by non-surgical periodontal therapy. Nineteen sites of non-adjacent teeth of four different patients were evaluated. Five milligram of PLGA microspheres loaded with 16 doxycycline hyclate (DOX) was administered per periodontal site. To quantify DOX released into the periodontal pocket, gingival crevicular fluid (GCF) was collected from the sites on days 2, 5, 7, 10, 15, and 20 after DOX application, and high-performance liquid chromatography was performed. Data were statistically assessed by ANOVA/Tukey test. At days 2, 5, and 7, the DOX concentration was stably sustained (23.33 ± 1.38, 23.4 ± 1.82, and 22.75 ± 1.33 μg/mL, respectively), with no significant differences over these assessment times (p > 0.05). At days 10 and 15, a tendency was observed toward a decrease in DOX concentration (21.74 ± 0.91 and 20.53 ± 4.88 μg/mL, respectively), but a significant decrease in GCF drug concentration (19.69 ± 4.70 μg/mL) was observed only on day 20. The DOX delivery system developed demonstrated a successful sustained release after local administration, as an adjunct to non-surgical periodontal therapy.  相似文献   
109.
BackgroundBreast-conserving treatment (BCT) provides better quality of life (QL) than mastectomy without reconstruction. Oncoplastic surgery (OS) encompasses a series of surgical techniques, increasing the indications for BCT, but few studies have evaluated the impact on QL in patients who undergo BCT with OS.Materials and MethodsA prospective, cross-sectional study was conducted in women who underwent BCT. We evaluated the characteristics of patients who underwent BCT with and without OS and the associated QL. QL was assessed through the EORTC QLQ-30, EORTC QLQ-BR23, and Breast Cancer Treatment Outcome Scale (BCTOS) questionnaires.ResultsA total of 300 patients underwent BCT, 72 underwent breast OS, and 37 underwent bilateral surgery. Patients who underwent OS were younger (p = 0.004), had a higher level of education (p = 0.01), had a smaller time interval since the end of treatment (p = 0.02), had tumours with greater dimensions (p = 0.003), and were more likely to receive neoadjuvant chemotherapy (p = 0.05). Based on the QL questionnaires, no difference was observed between the groups. Breast symmetry was not associated with high patient satisfaction (p = 0.55).ConclusionDespite the fact that OS was performed in patients with worse tumour conditions and in more demanding patients, OS allowed similar cosmetic results to classical BCT.  相似文献   
110.
The anti-inflammatory activity of Canavalia seed lectins (Canavalia gladiata [CGL], Canavalia maritima [ConM] and Canavalia brasiliensis [ConBr]) was evaluated by intravenous administration in rats. In non-sensitized rats, cellular edema elicited by carrageenan was reduced (45–51 %) by ConM and (44–59 %) by CGL. Osmotic edema elicited by dextran was reduced by ConM and CGL in 27 % and 29 %. ConM and CGL reduced the edema elicited by l-arginine in 53 % and that of prostaglandin E2 in 48 % and 36 %. Leukocyte migration elicited by carrageenan was reduced in 49 % by ConM and in 55 % by CGL (attenuated in 4× by glucose) and peritoneal TNF-α content in 82 %. In rats sensitized, ConM inhibited the paw edema and leukocyte migration elicited by ovalbumin in 34 % and 70 %. ConM and CGL are anti-inflammatory, mainly in cellular events mediated by prostaglandin E2, nitric oxide and TNF-α in non-sensitized rats. However, only ConM is anti-inflammatory in sensitized rats. CGL effect involves the lectin domain.  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