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Background. Therapeutic failure in preventing renal disease progression in type 2 diabetic nephropathy (DN) is due to a failure in the early detection of DN by microalbuminuria and the inappropriate correction of renal hemodynamic maladjustment secondary to glomerular endothelial dysfunction. Methods. Thirty patients associated with normoalbuminuric type 2 DN were subject to the following studies: tubular function by means of fractional excretion of magnesium (FE Mg), vascular function by means of determining the circulating endothelial cell, VEGF, VEGF/TGF B ratio, and intrarenal hemodynamic studies. Results. FE Mg, circulating endothelial cells, and TGF B were abnormally elevated, and VEGF/TGF B ratio was decreased in these normoalbuminuric patients. The intrarenal hemodynamic study revealed a hemodynamic maladjustment characterized by a preferential constriction at the efferent arteriole and a reduction in peritubular capillary flow. Following treatment with vasodilators, a decrease in efferent arteriolar resistance and increase in peritubular capillary flow as well as glomerular clearance were observed. Conclusion. FE Mg appears to be a more sensitive marker than microalbuminuria for the early detection of DN. Increased endothelial cell injury is reflected by enhanced circulating endothelial cell loss in conjunction with the increased TGF B and the decreased ratio between VEGF and TGF B. This is further supported by the dysfunctioning glomerular endothelium, which is characterized by hemodynamic maladjustment and a reduction in the peritubular capillary flow. A correction of such hemodynamic maladjustment by multidrug vasodilators effectively improves renal perfusion and restores renal function in type 2 DN.  相似文献   
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Renal microvascular disease and tubulointerstitial fibrosis are usually demonstrated in aging in humans and animals. It has recently been proposed that renal microvascular disease is the crucial determinant of tubulointerstitial disease or fibrosis. Enhanced circulating endothelial cell loss is a biomarker that reflects glomerular endothelial injury or renal microvascular disease, and fractional excretion of magnesium (FE Mg) is a sensitive biomarker that reflects an early stage of tubulointerstitial fibrosis. In aging in humans, both of these biomarkers are abnormally elevated. In addition, a glomerular endothelial dysfunction determined by altered hemodynamics associated with peritubular capillary flow reduction is substantiated. A correction of such hemodynamic alteration with vasodilators can effectively improve renal perfusion and restore renal function. Thus, anti-aging therapy can reverse the renal microvascular disease and dysfunction associated with the aging process.  相似文献   
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The in vitro activity of HR 756, 7-[2-(2-amino-4-thiazolyl)-2-(Z)-(methoximino)acetamido] cephalosporanic acid, was investigated against 659 isolates. HR 756 inhibited Neisseria and Haemophilus species at concentrations similar to those needed with ampicillin. It inhibited beta-lactamase-producing N. gonorrhoeae and H. influenzae. HR 756 was the most active compound tested against members of the Enterobacteriaceae, inhibiting most isolates of Escherichia coli, Klebsiella pneumoniae, Proteus mirabilis, Salmonella, Enterobacter, and Shigella at concentrations of less than 0.1 mug/ml. It was twice as active as carbenicillin against Pseudomonas aeruginosa and inhibited Bacteroides fragilis as well as cefoxitin. HR 756 killed E. coli, Staphylococcus aureus, and P. aeruginosa at rates similar to other beta-lactam antibiotics.  相似文献   
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Oxidative stress has been proposed to be involved in colorectal cancer development. Many dark pigments of plants have potent oxidative stress preventive properties. In this study, unpolished Thai rice was assessed for antioxidant activity using 1,1-diphenyl-2-picrylhydrazyl (DPPH) and 2,2'-azinobis-3-ethylbenzothiazoline-6-sulfonic acid (ABTS) methods. Red strain unpolished Thai rice was also administered to rats exposed to azoxymethane (AOM) for induction of aberrant crypt foci (ACF). Serum malondialdehyde (MDA) and ferric reducing antioxidant power (FRAP) were investigated for cellular oxidative stress and serum antioxidants, respectively. Red pigment unpolished Thai rice demonstrated high antioxidant activity and was found to significantly and dose dependently decrease the total density and crypt multiplicity of ACF. Consumption of Thai rice further resulted in high serum antioxidant activity and low MDA cellular oxidative stress. Interestingly, the density of ACF was strongly related to MDA at r=0.964, while it was inversely related with FRAP antioxidants (r=-0.915, p<0.001). The results of this study suggest that the consumption of red strain of unpolished Thai rice may exert potentially beneficial effects on colorectal cancer through decrease in the level of oxidative stress.  相似文献   
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Recognition of early stage of diabetic kidney disease, under common practice using biomarkers, namely microalbuminuria, serum creatinine level above 1?mg/dL and accepted definition of diabetic kidney disease associated with creatinine clearance value below 60?mL/min/1.73?m2, is unlikely. This would lead to delay treatment associated with therapeutic resistance to vasodilator due to a defective vascular homoeostasis. Other alternative biomarkers related to the state of microalbuminuria is not sensitive to screen for early diabetic kidney disease (stages I, II). In this regard, a better diagnostic markers to serve for this purpose are creatinine clearance, fractional excretion of magnesium (FE Mg), cystatin C. Recently, renal microvascular disease and renal ischemia have been demonstrated to correlate indirectly with the development of diabetic kidney disease and its function. Among these are angiogenic and anti-angiogenic factors, namely VEGF, VEGF receptors, angiopoietins and endostatin. With respect to therapeutic prevention, implementation of treatment at early stage of diabetic and nondiabetic kidney disease is able to restore renal perfusion and function.  相似文献   
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Interleukin 12 (IL‐12) is an inflammatory cytokine that promotes the response of the immune system. This cytokine has been implicated as a potent stimulator of several diseases characterized by inflammatory‐induced bone destruction, such as rheumatoid arthritis and periodontitis. Yet, the exact role of IL‐12 in the development and progress of periodontitis has not been clarified. Several studies have demonstrated a positive correlation between the level of IL‐12 and the severity of periodontal destruction. Deletion of IL‐12 in mice with periodontitis significantly suppressed the level of bone destruction. Interestingly, next to a role in modulating the pathogenesis, IL‐12 also has immunological‐regulatory properties. This cytokine induces expression of immunosuppressive molecules, such as indoleamine‐pyrrole 2,3‐dioxygenase (IDO). Thus, these findings suggest both negative and positive influences of IL‐12 in periodontal disease. It is currently proposed that the diversity of action of cytokines is a molecular key which regulates biological development and homeostasis. Accordingly, the actions of IL‐12 might be one of the mechanisms that regulate homeostasis of periodontal tissue during and following inflammation. Therefore, this article aims to review both destructive and protective functionalities of IL‐12 with an emphasis on periodontal disease.  相似文献   
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Streptococcus suis causes meningitis, septicemia, arthritis, endocarditis and death in both pigs and humans. Sudden death is rarely documented in the forensic field and almost all cases were diagnosed pre-mortem. Here we report a 49-year-old man who died from S. suis type 2 infection. S. suis was identified as the causative pathogen using bacterial culture, standard biochemical and coagglutination tests, specific DNA amplification by polymerase chain reaction, and histopathologic examination. We discuss the postmortem investigation of a suspected S. suis infection.  相似文献   
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