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171.
OBJECTIVE: The objective of the study was to examine the alterations of fibrin generation in dogs with haemangiosarcoma using resonance thrombography. The second objective was to evaluate the sensitivity of this method for the detection of hypofibrinogenaemia and/or increased fibrin(ogen) degradation product (FDP) concentration. ANIMALS, METHODS: Resonance thrombogram (RTG) measurements with two different instruments were performed in 30 unselected dogs with haemangiosarcoma, 14 of which had decreased fibrinogen and 28 of which had an increased FDP concentration (p<0.0001). RESULTS: The RTG-reaction time was less sensitive than the fibrin formation time (RTG-f) and fibrin amplitude (RTG-F). The RTG-f and RTG-F indicated reliably a decrease in fibrinogen concentration (sensitivity: 0.93). The sensitivity of detection of increased FDP levels was considerably higher than that of thrombin time. However, false-negative results were found even at FDP concentrations > or =120 mg/l, especially in cases with high fibrinogen level. Both machines showed similar sensitivity. CONCLUSIONS: The results of this study indicate that canine haemangiosarcoma is frequently associated with severe alterations of fibrin generation due to low fibrinogen and high FDP levels leading to distinct RTG abnormalities. The global test RTG reacts sensitively to a decreased fibrinogen level whereas its accuracy to detect FDP concentrations occurring under pathophysiological conditions is limited. A significant alteration of fibrin generation induced by FDPs may not occur until the serum FDP concentration exceeds 60 mg/l.  相似文献   
172.
BACKGROUND: The purpose of this study was to test the feasibility and effectiveness of cryoablation therapy (SurgiFrost trade mark CryoCath, Endocare Inc., Irvine, California, USA) for linear epicardial treatment of atrial fibrillation in an acute off-pump sheep model. METHODS: After thoracotomy, we performed epicardial cryoablation (2 min intervals at -160 degrees C) with pacing electrodes positioned at the left atrial appendage (LAA), the pulmonary veins (PVs), the right atrial appendage (RAA), and the vena cava cranialis (VCC) in 8 sheep. Circular epicardial ablations were performed with online temperature measurement in the ascending aorta and in the esophagus. The sheep were sacrificed two hours after ablation procedure, and heart, lungs, and esophagus were retrieved for histological examination. Out of all 8 sheep, histo-pathological analysis was performed on the RAA and VCC in 6 sheep and on the CAA and PV in all 8 sheep. RESULTS: Thin-walled structures such as PVs and VCC showed electrical isolation. No significant changes in temperature in the descending aorta and the esophagus were observed. There was evidence of extensive transmural alteration including vascular lesions, myocardial degeneration and necrosis as well as epi- and endocardial necrosis in the left atria in three of 8 cases, in the right atria in 5 of 6 cases, in the VCC in 6 of 6 cases, and in the PV in 5 of 8 cases. Mild lesions of the muscular layer of the esophagus were found in 7 of 8 cases. CONCLUSIONS: Epicardial cryoablation is not effective on thicker tissues like LAA and RAA due to the rewarming of the current blood flow. However, thin tissues like VCC and PV can be isolated. Further chronic studies are necessary to evaluate the potential for regeneration of adjacent structures.  相似文献   
173.
Thromboembolism in pregnancy is a major contributor to pregnancy morbidity and mortality with potentially serious adverse effects for both mother and fetus. The purposes of this article are to explore the impact of heritable and acquired thrombophilias on pregnancy and to determine the appropriateness of screening for thrombophilias in pregnancy. In determining the appropriateness of screening, attention was given to the changes that occur in the coagulation and fibrinolytic systems during normal pregnancy. The impact of different heritable and acquired thrombophilias on maternal venous thromboembolism, fetal loss, and its impact on certain obstetric conditions are then explored. Guidelines and conclusions are made as to the appropriateness of screening. TARGET AUDIENCE: Obstetricians & Gynecologists, Family Physicians. LEARNING OBJECTIVES: After completion of this article, the reader should be able to list the various thrombophilias associate with pregnancy, to describe the impact of thrombophilias on pregnancy, and to outline the appropriate screening guidelines for thrombophilias during pregnancy.  相似文献   
174.
A total of 40 patients with acute pelvic inflammatory disease (acute PID) were examined over a period of 7 months to determine the diagnostic value of laparoscopic examination in these cases. The most important findings were: the clinical diagnosis of acute PID was confirmed by laparoscopy in 55% of patients; laparoscopy was especially of value in differentiating potentially lethal conditions such as ectopic pregnancy and acute appendicitis from acute PID in 15% of patients; laparoscopically obtained microbiological specimens provide a more accurate means of determining the microbiological aetiology of acute PID than vaginally obtained specimens.  相似文献   
175.
The mitogen-activated protein kinase (MAPK) p38 modulates a variety of cellular functions, including proliferation, differentiation and cell death. However, we report here a novel function for p38, i.e. the regulation of cytotoxic lymphocyte-mediated cytotoxicity. Stimulation of NK cells by either cross-linking of their FcgammaRIII receptors or by binding to NK-sensitive target cells induces the phosphorylation and activation of p38, and also of its upstream regulators MKK3/MKK6. Pharmacologic analyses suggest that Src-family and Syk-family protein tyrosine kinases couple the NK cell surface receptors to p38 activation. The role of p38 in the cytotoxic function of NK cells was tested by treatment of NK cells with the cell-permeable, p38-specific inhibitor SB203580. Interestingly, exposure to the drug reduced both antibody-dependent cellular cytotoxicity and natural cytotoxicity, but maximal inhibitory concentrations resulted in only partial inhibition. Collectively, these results suggest that the p38 MAPK pathway is stimulated during the development of NK cell-mediated cytotoxicity and that efficient killing is influenced by both p38-dependent and p38-independent pathways. More broadly, this study identifies the regulation of cell-mediated killing as a novel role for p38 in cytotoxic lymphocytes.  相似文献   
176.
BACKGROUND: Earlier studies have documented that the prevalence of decreased bone mineral density (BMD) is elevated in patients with inflammatory bowel disease. The objective of this study was to investigate the prevalence of vertebral deformities in inflammatory bowel disease patients and their relation with BMD and bone turnover. METHODS: One hundred and nine patients with Crohn's disease (CD) and 72 with ulcerative colitis (UC) (age 44.5+/-14.2 years) were studied. BMD of the hip (by dual X-ray absorptiometry) was measured and a lateral single energy densitometry of the spine for assessment of vertebral deformities was performed. Serum markers of bone resorption (carboxy-terminal cross-linked telopeptide of type I collagen) and formation (procollagen type I amino-terminal propeptide) were measured, and determinants of prevalent vertebral deformities were assessed using logistic regression analysis. RESULTS: Vertebral deformities were found in 25% of both CD and UC patients. Comparing patients with and without vertebral deformities, no significant difference was found between Z-scores and T-scores of BMD, or levels of serum carboxy-terminal cross-linked telopeptide of type I collagen and serum procollagen type I amino-terminal propeptide. Using logistic regression analysis the only determinant of any morphometric vertebral deformity was sex. The presence of multiple vertebral deformities was associated with older age and glucocorticoid use. CONCLUSION: The prevalence of morphometric vertebral deformities is high in CD and UC. Male sex, but neither disease activity, bone turnover markers, clinical risk factors, nor BMD predicted their presence. The determinants for having more than one vertebral deformity were age and glucocorticoid use. This implies that in addition to screening for low BMD, morphometric assessment of vertebral deformities is warranted in CD and UC.  相似文献   
177.
The atrioventricular valves of 25 dogs of different breeds and age were examined grossly and microscopically following histochemical staining and immunohistochemical labelling for collagen types I, III and VI, and for fibronectin and laminin. Foci of cartilage were identified in the tricuspid septal leaflet within the fibrosa (n=21) or spongiosa (n=3). These were further characterized as either fibrocartilage, predominantly composed of collagens I and VI, or hyaline cartilage consisting of laminin and collagens III and VI. Eighteen of the dogs were of large breed and seven of small breed. Retrospective echocardiographic findings were available from five cases and in three of these a hyperechogenic structure was identified corresponding to the cartilage focus (0.1, 1.12 and 5.63mm(2) in size). The clinical significance and mechanism of formation of these cartilaginous foci remain undetermined, although factors such as breed, size and concurrent chronic valvular disease may be significant.  相似文献   
178.
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