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51.
Introduction There is a known difference in breast cancer survival between races in the US for which several factors such as social, lifestyle and genetic factors may be relevant. Method This is a retrospective study among women entitled to free treatment in the US department of defense health care system. Within this group, we investigated the temporal trend of absolute survival of 13,793 of White and African American aged 20–59 years and diagnosed between 1980 and 1999 with breast cancer. Result There is a 3% overall improvement in survival in whites which can be explained by an earlier detection, and a two percent decrease in AA with a distinct pattern by age group. In the 40–49 year age group, the survival in white increases from 84.5% in the year 1980–1984 to 87.4 % in the year 1995–1999, in AA we estimate a decrease from 79.7% to 78.5%. When accounting for stage at diagnosis a slight reduction in survival in whites and a strong reduction in AA indicates a significant interaction between race and calendar period. The differences in survival patterns between blacks and whites are mainly caused by breast cancer and not by other causes. Conclusion The gap in survival which strongly increased with calendar period cannot be explained by unequal access to health care. Possible explanations include a lower participation of early detection programs for breast cancer in AA and an increasing prevalence of obesity over time which is more pronounced in AA than in whites.  相似文献   
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Injecting drug users (IDU) were enrolled from two detoxification clinics and two needle/syringe exchange programmes (NEP) in central and northwest Bangladesh. Syphilis, hepatitis C and HIV rates were highest in IDU from the NEP of central Bangladesh (23, 66.5 and 1.4%, respectively), whereas current hepatitis B infection rates were highest in IDU from the NEP of northwest Bangladesh (12%). Five HIV strains were subtype C and one E/B. The 32 base pair (bp) deletion of the CCR5 gene was not detected.  相似文献   
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In this ongoing prospective study conducted in University Cardiac Center, Bangabandhu Sheikh Mujib Medical University (BSMMU), Dhaka, from July 2004 to January 2006. Fifty (50) patients (mean age 56+/-7.2 years) underwent stentangioplasty were evaluated. The study group of 50 patients consisted of 42 (84%) men and 08 (16%) women. The aim of this study was to evaluate in-hospital success, failure and complications during the procedures. About risk factors 19(38%) had hypertension, 13(26%) were smoker, 11(22%) suffered from diabetes mellitus, 05(10%) had family history of ischaemic heart disease. Average left ventricular ejection fraction was 54+/-7. Target vessel percutaneous coronary angioplasty (PTCA) were done in 61 vessel, intracoronary stent implanted in 58 vessels, direct stenting were done in 35 cases, failed PTCA were in 03(6%) cases and two had dissection. The native vessels had a mean reference diameter of 2.91 mm and their luminal diameter increased significantly after percutaneous coronary intervention (PCI). All the patients were discharged by one to three days of the procedure with improvement of their clinical condition. In conclusion, intracoronary stent deployment in coronary artery stenosis following balloon angioplasty is a valid and beneficial strategy with good in-hospital results.  相似文献   
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BACKGROUND: Low birth weight is generally an outcome of a fetal insult or nutritional insufficiency. Recent studies have shown that such exposure early in life may have long-term implications for later immunocompetence and susceptibility to infectious diseases. OBJECTIVE: We aimed to investigate the effect of birth weight on immune function in preschool-age children. DESIGN: A birth cohort cross-sectional study was conducted in children (n = 132) aged 60.8 +/- 0.32 mo who were born in Matlab, a rural area of Bangladesh, and whose weight and length were measured within 72 h of birth. The outcome measures were thymopoiesis, T cell turnover, acute phase response, and percentage of lymphocytes. RESULTS: Children born with low birth weight (<2500 g; LBW group, n = 66) had significantly higher concentrations of T cell receptor excision circles in peripheral blood mononuclear cells-a biomarker for thymopoiesis-and significantly higher serum bactericidal activity and C-reactive protein concentrations than did children born with normal birth weight (>or=2500 g; NBW group, n = 66) (P < 0.05 for both). The LBW group children had significantly lower concentrations of interleukin 7 in plasma (P = 0.02), shorter telomere length in peripheral blood mononuclear cells (P = 0.02), and a lower percentage of CD3 T cells (P = 0.06) than did the NBW group children. CONCLUSIONS: Greater peripheral T cell turnover (shorter telomeres and lower CD3 concentrations) due to immune activation (elevated C-reactive protein concentrations and bactericidal activity) may have resulted in a greater need for replenishment from the thymus (higher T cell receptor excision circles); these events may cause lower immune functional reserve in preschool-age children born with LBW. Thus, LBW has implications for immunocompetence and increased vulnerability to infectious diseases in later life.  相似文献   
56.
Three dimensional (3D) bioplotting requires appropriate crosslinkers to crosslink the hydrogel precursor while simultaneously maintaining the viability of embedded cells. However, the evaluation and comparison of various types of crosslinkers in bioplotting remains underexplored to date. This paper presents our study of the influence of three ionic crosslinkers—calcium chloride (CaCl2), barium chloride (BaCl2), and zinc chloride (ZnCl2)—on the mechanical and biological properties of 3D bioplotted alginate scaffolds. The scaffold mechanical properties characterized included the elastic modulus, swelling, and degradation while the biological properties considered included Schwann cell viability and surface morphology. The mechanical and biological properties of the bioplotted scaffolds were both dependent on the crosslinkers used for fabrication; specifically, crosslinking ions resulted in the elastic modulus of the hydrogels decreasing in the order BaCl2>CaCl2>ZnCl2 over 42 days while Schwann cell viability decreased in the order CaCl2>BaCl2>ZnCl2 over 7 days. Taken together, these results offer insights that are effective in terms of manipulating the 3D bioplotting process so as to tune and optimize the mechanical and biological performance of the plotted scaffolds for tissue engineering applications.  相似文献   
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Glycyrrhiza glabra L. (Fabaceae), commonly known as ‘liquorice’, is a well‐known medicinal plant. Roots of this plant have long been used as a sweetening and flavouring agent in food and pharmaceutical products, and also as a traditional remedy for cough, upper and lower respiratory ailments, kidney stones, hepatitis C, skin disorder, cardiovascular diseases, diabetes, gastrointestinal ulcers and stomach ache. Previous pharmacological and clinical studies have revealed its antitussive, antiinflammatory, antiviral, antimicrobial, antioxidant, immunomodulatory, hepatoprotective and cardioprotective properties. While glycyrrhizin, a sweet‐tasting triterpene saponin, is the principal bioactive compound, several bioactive flavonoids and isoflavonoids are also present in the roots of this plant. In the present study, the cytotoxicity of the methanol extracts of nine samples of the roots of G. glabra, collected from various geographical origins, was assessed against immortal human keratinocyte (HaCaT), lung adenocarcinoma (A549) and liver carcinoma (HepG2) cell lines using the in vitro 3‐[4,5‐dimethylthiazol‐2‐yl]‐2,5‐diphenyl tetrazoliumbromide cell toxicity/viability assay. Considerable variations in levels of cytotoxicity were observed among various samples of G. glabra. Copyright © 2015 John Wiley & Sons, Ltd.  相似文献   
59.
TO THE EDITOR: The increased severity of Clostridium difficile infection is primarily attributed to the appearance of an epidemic strain characterized as PCR ribotype 027 (1). The only report that identified epidemic C. difficile ribotype 027 in an American country outside of North America comes from Costa Rica, raising the possibility that strains 027 might also be present in other countries of Latin America (2). Several studies between 2001 and 2009 have been conducted in South American countries to detect the incidence of C. difficile infection in hospitalized patients, but they did not identify which C. difficile strains were causing these infections (3).  相似文献   
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