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141.
The effect of low-level laser therapy (LLLT) on the cardiovascular system is not fully established. Since the endothelium is an important endocrine element, establishing the mechanisms of LLLT action is an important issue.The aim of the study was to evaluate the effect of transdermal LLLT on endothelial function.In this study, healthy volunteers (n?=?40, age?=?20–40 years) were enrolled. N?=?30 (14 female, 16 male, mean age 30?±?5 years) constituted the laser-irradiated group (LG). The remaining 10 subjects (6 women, 4 men, mean age 28?±?5 years) constituted the control group (CG). Participants were subjected to LLLT once a day for three consecutive days. Blood for biochemical assessments was drawn before the first irradiation and 24 h after the last session. In the LG, transdermal illumination of radial artery was conducted (a semiconductor laser λ?=?808 nm, irradiation 50 mW, energy density 1.6 W/cm2 and a dose 20 J/day, a total dose of 60 J). Biochemical parameters (reflecting angiogenesis: vascular endothelial growth factor (VEGF), fibroblast growth factor (FGF), angiostatin; antioxidative status: glutathione (GSH) and the nitric oxide metabolic pathway: symmetric dimethylarginine (SDMA), asymmetric dimethylarginine (ADMA) and l-arginine) were assessed. In the LG, a significant increase in GSH levels and considerable decrease in angiostatin concentration following the LLLT were observed. No significant differences in levels of the VEGF, FGF, SDMA, ADMA were observed.LLLT modifies vascular endothelial function by increasing its antioxidant and angiogenic potential. We found no significant differences in levels of the nitric oxide pathway metabolites within 24 h following the LLLT irradiation.  相似文献   
142.
We searched for an association between the interleukin 4 receptor gene (IL4R) rs1805015 and interleukin 13 gene (IL13) rs20541 polymorphisms and the development of antibodies to hepatitis B surface antigen (anti-HBs) in the case of hepatitis B virus (HBV) vaccination or infection in hemodialysis (HD) patients. HD patients who failed to respond to HBV vaccination did not differ in genotype frequencies of IL4R (TT 72.7%, CT 22.6%, CC 4.7%) and IL13 (CC 59.0%, CT 34.2%, TT 6.8%) from vaccine responders (IL4R TT 68.0%, CT 27.3%, CC 4.7%; IL13 CC 55.0%, CT 38.5%, TT 6.5%). HD patients who did not develop anti-HBs despite HBV infection also did not differ in genotype frequencies of IL4R (TT 67.8%, CT 26.8%, CC 5.4%) and IL13 (CC 60.7%, CT 33.9%, TT 5.4%) from HD patients who developed an anti-HBs response (IL4R TT 65.4%, CT 30.8%, CC 3.8%; IL13 CC 60.5%, CT 34.6%, TT 4.9%). In HD patients, neither the IL4R nor IL13 polymorphism is associated with anti-HBs development irrespective of whether an immunization is provoked by HBV vaccination or HBV infection.  相似文献   
143.
The objectives of this study were to assess the incidence of invasive pneumococcal disease (IPD) in Poland (2006-2009), where mass vaccination had not been implemented, and to determine the serotype distribution and antimicrobial susceptibility of Streptococcus pneumoniae isolates. The IPD incidence rates were highest among children under 2 years of age (3.39/100,000 in 2009) and children 2-5 years old (2.44/100,000). The most common serotypes were 14, 3, 1, 4, 19F, 23F, 6B, and 12F (61.7% of all isolates). In children aged less than 5 years, isolates of serotypes 14, 6B, and 19F were most prevalent (52.7% of the IPD cases). The PCV7, PCV10, and PCV13 covered 43.3%, 54.8%, and 68.8% of all IPD cases, and 68.7%, 76.3%, and 86.3% of cases involving children under 5 years of age. Penicillin resistance was found in 21.3% of the isolates responsible for meningitis and in 1.2% of isolates responsible for other invasive infections.Introduction of antipneumococcal conjugated vaccines into the national immunisation programme would likely lead to a significant reduction of IPD-associated morbidity among Polish children in particular, as well as in the population as a whole, especially in cases involving pneumococci with a decreased susceptibility to antibiotics.  相似文献   
144.
Central visual fields were investigated by automated static perimetry in a group of healthy myopic individuals with peripapillary crescents and tigroid fundus changes only. Results were compared with 'emmetropic' and 'myopic subjects without crescents' control groups. The sample comprised 122 young, healthy volunteers between the ages of 18.5 and 35.4 years, free from any ocular or systemic disease, with refractive errors ranging from +4.00 D to −25.75 D. Central visual fields were examined using programs 30-2 and 30-1 of the Humphrey Field Analyzer (HFA), which in combination yield a test point resolution of 4.2° within the central 30°. Visual field analysis showed a decline in the differential light sensitivity in myopes with peripapillary changes only, compared with the control groups. These field changes became more pronounced as the degree of myopia, axial length and area of the peripapillary crescent increased. Results suggest that the sensitivity decline of the central field occurs in subjects with axial lengths above 26 mm and more than 5 D of myopia. Knowledge of the likely field defects encountered in myopia will assist practitioners to distinguish between physiological and pathological fields in myopes.  相似文献   
145.
BACKGROUND: Results of peritoneal equilibration test (PET) suggest prolonged effect of polyglucose dialysis solution (PG-DS) on peritoneal permeability. OBJECTIVES: An evaluation of dialysate-to-plasma ratio (D/P) of urea, DIP creatinine, and D/D0 glucose (ratio of dialysate glucose at designated dwell time to dialysate glucose at 0 dwell time), and mass transfer area coefficients (KBD) of these solutes in PET before introduction, during administration, and after discontinuation of PG-DS hi patients treated with continuous ambulatory peritoneal dialysis (CAPD). DESIGN: Single-center prospective study with PG-DS; retrospective selection of the control group. SETTING: Peritoneal dialysis unit in a university hospital. PATIENTS: Fourteen patients (11 males; age 45.1 +/- 8.5 years) treated with CAPD for 17.5 +/- 9.9 months. 7.5% PG-DS was used for the overnight exchange. After discontinuation of the PG-DS, standard dialysis solutions, as previously used, were reintroduced. The control group was selected to match both CAPO duration and peritoneal permeability of the patients in the PG-DS group at the start of the study. METHODS: Standard PET was carried out at 1.6 +/- 0.8 months before the introduction of PG-DS (study period I, n = 14), after 1.2 +/- 0.6 months' use of PG-DS (study period II, n = 14), after 4.4 +/- 0.8 months' use of PG-DS (study period Ill, n = 11), after 8.8 +/- 2.2 months' use of PG-DS (study period IV, n = 9), and at 2.0 +/- 0.6 months after PG-DS discontinuation (study period V, n = 11). Patients in the control group underwent PET at similar time intervals (control periods I-V). RESULTS: In the PG-DS group, a tendency toward increased peritoneal permeability for urea and creatinine was shown during the consecutive study periods. D/D0 glucose was significantly higher only in the PET performed during use of PG-DS (periods II-IV) compared to results obtained in period I. In the control group, both D/P and KBD of both urea and creatinine remained unchanged, but K90 glucose was higher in the first 2 hours of the PET in control period V compared to respective values in control period III. CONCLUSION: Changes in peritoneal permeability are observed In CAPD patients treated with PG-DS. These changes may be at least partially related to the administration of polyglucose.  相似文献   
146.
AIMS/BACKGROUND: Green illumination is commonly used to image vessels of the retina and conjunctiva. The purpose was to derive the best optical set-up for imaging vessels of the conjunctiva. METHODS: The concept of exposure density was used to predict a digital camera response to imaging vessels on a scleral background. Practical verification was performed to verify vessel contrast because of the difficulties in measuring the spectral components of the imaging system, such as the spectral reflectivity of vessels and sclera. Images of the same conjunctiva were repetitively taken through different coloured filters, using the Nikon FS-2 photo slit-lamp and recorded on different coloured channels of the Kodak DCS 100 digital camera. Gaussian blurred tubular models were fitted to densitometric profiles across three vessels from each image, allowing vessel contrast and width to be objectively measured. These measures were compared using different optical set-ups. RESULTS: Optimal exposure density calculations and vessel contrast was obtained with the xenon light source filtered with Wratten 99 (green) and Wratten 96 (neutral density, 0.2 log units) gelatine absorption filters using the green channel of the digital camera. This image set-up was associated with a 46% (99% CI 43-51%) to 64% (99% CI 58-72%) increase in contrast compared with vessels imaged without filtration, using the combined colour channel of the digital camera. Although differences in vessel widths resulted, absolute differences were marginal. CONCLUSION: With the increased use of digital imaging, and the need for image processing of vascular networks, image optimisation is beneficial. This study verified the optimal set-up for non-invasively imaging vessels of the bulbar conjunctiva.  相似文献   
147.
PURPOSE: To determine the cytotoxicity potential of soft contact lens disinfection solutions. METHODS: Three modifications of the United States Pharmacopeia (USP) elution test were conducted: trypan blue uptake test; regrowth of cells after exposure; and quantitation of viable cells after exposure test. Cycled lenses were also tested according to the USP direct-contact test. We compared the cytotoxicity profile of neutralized AOSept (CIBA Vision, Duluth, GA) disinfectant, SOLO-care Soft (CIBA Vision, Duluth, GA) brand multipurpose solution, OPTI-FREE Express (Alcon, Ft. Worth, TX) multipurpose disinfecting solution (with ALDOX), ReNu (Bausch & Lomb, Rochester, NY) multipurpose solution, ReNu MultiPlus (Bausch & Lomb, Rochester, NY) multipurpose solution, and COMPLETE Comfort PLUS (Allergan, Irvine, CA) multipurpose solution. Appropriate positive and negative controls were used for each test. RESULTS: Neutralized AOSept, SOLO-care soft, and COMPLETE Comfort PLUS solutions were noncytotoxic by all four test methods. ReNu MPS and ReNu MultiPlus both were noncytotoxic by the USP direct contact test and the USP elution-based trypan blue uptake and cell regrowth tests, but both yielded less than 50% of viable cells. In the three USP Elution test methods, OPTI-FREE Express (with ALDOX) exhibited cytotoxicity. CONCLUSIONS: These solutions have shown widely varying cytotoxicity potential. Neutralized AOSept, SOLO-Care Soft, and COMPLETE Comfort Plus were noncytotoxic by all four tests. ReNu MultiPlus and ReNu MPS inhibited the growth of cells after exposure. OPTI-FREE Express (with ALDOX) may have a higher potential for ocular irritation correlating to severe cytotoxicity in vitro.  相似文献   
148.
149.
Primary biliary cirrhosis (PBC) is an autoimmune liver disease with unknown etiology. Patients with PBC have antimitochondrial autoantibodies (AMA) and additionally 50% of them have antinuclear antibodies (ANA). A 15-amino acid fragment (DRKASPPSGLWSPAY) from the C-terminal part of the nuclear envelope glycoprotein gp210 has been proposed as one of the antigenic targets for ANA. The aim of this work was to develop an immunoenzymatic assay for determination of gp210 autoantibodies using for its binding a synthetic pentadecapeptide derived from the gp210 amino acid sequence and to determine level of these autoantibodies in sera of patients with PBC and other autoimmune liver diseases from Poland. Polystyrene microtitration plates coated with the synthetic peptide were consecutively incubated with diluted sera, anti-human immunoglobulin G (IgG) antibodies conjugated with horseradish peroxidase, and with tetramethylobenzidine. Optical density (OD) was read at 450 nm. The mean values of the intra- and interassay of variation coefficients of the test were 4.1 and 10.2%, respectively. Anti-gp210 was detected in 44% of PBC patients and in 6% of patients with PSC. The results were negative for healthy blood donors and other controls. The specificity of the test was 99%, so the anti-gp-210 autoantibodies estimated on DRKASPPSGLWSPAY can be a reliable marker of PBC.  相似文献   
150.
New vectors and strategies for cardiovascular gene therapy   总被引:3,自引:0,他引:3  
Cardiovascular diseases are the major cause of morbidity and mortality in both men and women in industrially developed countries. These disorders may result from impaired angiogenesis, particularly in response to hypoxia. Despite many limitations, gene therapy is still emerging as a potential alternative for patients who are not candidates for traditional revascularization procedures, like angioplasty or vein grafts. This review focuses on recent approaches in the development of new gene delivery vectors, with great respect to newly discovered AAV serotypes and their modified forms. Moreover, some new cardiovascular gene therapy strategies have been highlighted, such as combination of different angiogenic growth factors or simultaneous application of genes and progenitor cells in order to obtain stable and functional blood vessels in ischemic tissue.  相似文献   
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