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   175篇
  免费   6篇
  国内免费   7篇
耳鼻咽喉   1篇
儿科学   34篇
妇产科学   3篇
基础医学   8篇
口腔科学   9篇
临床医学   23篇
内科学   23篇
皮肤病学   4篇
神经病学   4篇
特种医学   46篇
外科学   3篇
综合类   1篇
预防医学   13篇
眼科学   4篇
药学   8篇
肿瘤学   4篇
  2023年   1篇
  2021年   1篇
  2019年   2篇
  2018年   1篇
  2017年   1篇
  2016年   2篇
  2015年   5篇
  2014年   5篇
  2013年   3篇
  2012年   4篇
  2011年   2篇
  2010年   8篇
  2009年   8篇
  2008年   6篇
  2007年   10篇
  2006年   1篇
  2004年   1篇
  2003年   2篇
  2002年   1篇
  2001年   2篇
  2000年   1篇
  1999年   6篇
  1998年   16篇
  1997年   13篇
  1996年   14篇
  1995年   8篇
  1994年   5篇
  1993年   8篇
  1992年   3篇
  1991年   1篇
  1990年   2篇
  1989年   2篇
  1988年   3篇
  1987年   2篇
  1986年   3篇
  1985年   7篇
  1984年   5篇
  1983年   1篇
  1982年   1篇
  1981年   2篇
  1980年   4篇
  1978年   1篇
  1977年   6篇
  1976年   6篇
  1975年   2篇
排序方式: 共有188条查询结果,搜索用时 459 毫秒
181.
182.

Background  

Depressive disorder is one of the most common disorders, and is highly prevalent in chronically ill patients. The presence of comorbid depression has a negative influence on quality of life, health care costs, self-care, morbidity, and mortality. Early diagnosis and well-organized treatment of depression has a positive influence on these aspects. Earlier research in the USA has reported good results with regard to the treatment of depression with a collaborative care approach and an antidepressant algorithm. In the UK 'Problem Solving Treatment' has proved to be feasible. However, in the general hospital setting this approach has not yet been evaluated.  相似文献   
183.
Scarce evidence suggests that inflammatory and metabolic dysregulation predicts poor response to antidepressants, which could result in worse depression outcome. This study prospectively examined whether inflammatory and metabolic dysregulation predicted the 2-year course of depressive disorders among antidepressant users. Data were from the Netherlands Study of Depression and Anxiety, including 315 persons (18–65 years) with a current depressive disorder (major depressive disorder, dysthymia) at baseline according to the DSM-IV criteria and using antidepressants. Inflammatory (C-reactive protein, interleukin-6 (IL-6), tumor-necrosis factor-α) and metabolic (waist circumference, triglycerides, high-density lipoprotein (HDL) cholesterol, blood pressure, fasting glucose) factors were measured at baseline. Primary outcome for course of depression was indicated by whether or not a DSM-IV depressive disorder diagnosis was still/again present at 2-year follow-up, indicating chronicity of depression. Elevated IL-6, low HDL cholesterol, hypertriglyceridemia, and hyperglycemia were associated with chronicity of depression in antidepressant users. Persons showing ⩾4 inflammatory or metabolic dysregulations had a 1.90 increased odds of depression chronicity (95% CI=1.12–3.23). Among persons who recently (ie, at most 3 months) started antidepressant medication (N=103), having ⩾4 dysregulations was associated with a 6.85 increased odds of depression chronicity (95% CI=1.95–24.06). In conclusion, inflammatory and metabolic dysregulations were found to predict a more chronic course of depressive disorders among patients using antidepressants. This could suggest that inflammatory and metabolic dysregulation worsens depression course owing to reduced antidepressant treatment response and that alternative intervention treatments may be needed for depressed persons with inflammatory and metabolic dysregulation.  相似文献   
184.
BACKGROUND: Invasive aspergillosis (IA) is an important cause of morbidity and mortality among immunocompromised patients. Echinocandins are novel antifungal molecules with in vitro and in vivo activity against Aspergillus species. METHODS: We investigated the efficacy and safety of caspofungin in the treatment of IA. Ninety patients with IA who were refractory to or intolerant of amphotericin B, lipid formulations of amphotericin B, or triazoles were enrolled to receive caspofungin. RESULTS: Efficacy was assessed for 83 patients who had infection consistent with definitions of IA and who received >or=1 dose of study drug. Common underlying conditions included hematologic malignancy (48% of patients), allogeneic blood and marrow transplantation (25% of patients), and solid-organ transplantation (11% of patients). Seventy-one patients (86%) were refractory to and 12 patients (14%) were intolerant of previous therapy. A favorable response to caspofungin therapy was observed in 37 (45%) of 83 patients, including 32 (50%) of 64 with pulmonary aspergillosis and 3 (23%) of 13 with disseminated aspergillosis. Two patients discontinued caspofungin therapy because of drug-related adverse events. Drug-related nephrotoxicity and hepatotoxicity occurred infrequently. CONCLUSION: Caspofungin demonstrated usefulness in the salvage treatment of IA.  相似文献   
185.
186.
Gibson  RM; Kansas  GS; Tedder  TF; Furie  B; Furie  BC 《Blood》1995,85(1):151-158
P-selectin is an integral membrane glycoprotein on stimulated platelets and endothelial cells that serves as a receptor for leukocytes. To estimate the density of P-selectin in membranes necessary to support adhesion, we incorporated purified P-selectin at varying concentrations into phospholipid bilayers that encapsulated glass microspheres. Maximal binding of these lipospheres to HL60 cells, a P-selectin ligand- expressing cell line, was approached at a P-selectin density of about 100 molecules per microns 2; half-maximal binding was observed at about 50 to 60 molecules per microns 2. Compatible results were obtained with P-selectin expressed on Chinese hamster ovary cells. The P-selectin density on stimulated platelets was estimated to be 150 to 200 molecules/microns 2. To identify the domains of P-selectin required for HL60 cell binding, chimeras of P-selectin and L-selectin were stably expressed in Chinese hamster ovary cells and clones that expressed the chimeras at the estimated physiologic density were selected. Chimeras containing the P-selectin lectin and epidermal growth factor (EGF) domains or the lectin, EGF, and short consensus repeats bound HL60 cells equivalently, but a chimera containing the P-selectin lectin domain alone bound HL60 cells much less well. These results indicate that at a physiologically relevant P-selectin density on membrane surfaces, the lectin, and EGF domains of P-selectin are together required for optimal leukocyte binding.  相似文献   
187.
Experience with a transfusion recipient education program about hepatitis C   总被引:1,自引:0,他引:1  
Shortly after test kits for antibodies to the hepatitis C virus (HCV) were licensed in May of 1990, our medical community undertook a public education program encouraging previous transfusion recipients to see their physicians about the wisdom of being tested for anti-HCV. In response, 1034 samples were received for testing. All samples repeatably reactive (RR) with anti-HCV enzyme-linked immunoassay (EIA) were tested further with a research recombinant immunoblot assay (RIBA). Overall, 76 of the 1034 (7.4%) recipient samples were RR and 64 of these (84.2%) were reactive with RIBA. Recipients transfused prior to surrogate testing (alanine aminotransferase [ALT] and anti-hepatitis B core [anti-HBc]) in 1986 showed a 8.6 percent reactivity with RIBA and those transfused after surrogate testing showed a 4.8 percent reactivity, a 44 percent reduction. Of the 57 recipient samples reactive with RIBA and suitable for assay, 11 (19.3%) had an elevated ALT. Among 76 randomly selected blood donors with RR EIAs studied for comparison with recipients, 20 (26.3%) were reactive with RIBA, 9 of which had an abnormal surrogate test that would have disqualified them. ALT concentrations were abnormal in 6 (30%) of the donors who were reactive on RIBA. We conclude that an education program that encourages previous transfusion recipients to seek medical advice about anti-HCV testing is practical from the standpoint of the blood center. We believe more widespread implementation of similar programs should be considered.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
188.

Purpose

To perform qualitative analysis using scanning electron microscopy (SEM) of fracture surfaces for ceramic and polymeric dental materials broken via standardized flexural and crunch-the-crown (CTC) tests.

Materials and Methods

Zirconia, glass–ceramic, and polymeric (Trilor; TRI, Juvora; JUV, Pekkton; PEK) materials were loaded using crowns for CTC tests, discs (zirconia and glass–ceramics) for piston-on-3 ball tests, bars (polymer) for 3-point bend tests, and bars (zirconia, glass–ceramics) for 4-point bend tests. SEM was used to characterize the fracture surfaces and identify fracture surface features (e.g., origin, mist, hackle, and the direction of crack propagation [DCP]). Electron dispersive spectroscopy was used to identify the local chemistry.

Results

Fracture surface features were found to be less visually apparent for glass–ceramics than zirconia. For zirconia bars, fractures originated roughly midway between the corner and center for processing defects related to sintering. Fractures originated at the bottom corners of glass–ceramic bars (void or surface flaw) and PEK bars (surface flaw). TRI bar failures exposed glassy fibers. Fracture features were generally less discernable for discs compared to bars for zirconia and glass–ceramics. Ceramic crowns fractured into 2 to 3 pieces, with fractures originating at the occlusal surface and clear evidence for the DCP. Failures of TRI and JUV specimens (bars and crowns) were less catastrophic than for the ceramics, with exposed fibers (TRI) and surface cracks (JUV). PEK crown and bar fractures presented dimple (ductile) features formed due to microvoid coalescence followed by brittle crack propagation.

Conclusions

The critical flaws responsible for failure initiation were a function of material composition and test configuration. Fractographic analysis can reveal problems associated with the manufacturing of materials, their handling, grinding and finishing/polishing procedures, the structural design and choice of material, and the quality of the final laboratory-delivered restoration.  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