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41.
The aim of the study was to investigate whether a supplement of antioxidants to subjects with a high working pace can influence the antioxidant capacity. The study was parallel and double blind with 98 subjects randomised into two groups. One of the groups was given a test drink with antioxidants for 4 weeks (450 ml/day) while the other group took a corresponding amount of placebo drink. The test drink contained: 2 mg beta-carotene/100 ml, 40 mg alpha-tocopherol/100 ml, 80 mg ascorbic acid/100 ml, 2 mg pyridoxine/100 ml, 15 mg magnesium/100 ml, 0.2 mg manganese/100 ml, 1 mg zinc/100 ml, 0.1 mg copper/100 ml and 10 microg selenium/100 ml. Consumption of the test drink for 4 weeks increased the total plasma antioxidant capacity by 7% (ferric reducing ability of plasma method, P<0.05 compared with the placebo group), and the content of selenium and selenoprotein P in serum was raised by 16-17% (P<0.001 compared with the placebo group). No significant changes were found in the placebo group. The test drink also contained Lactobacillus plantarum 299v (5 x 10(7) cfu/ml) and 4 weeks' consumption led to a significant increase of Lb. plantarum 299v in the faeces. In conclusion, consumption of a drink rich in different antioxidants can increase the antioxidant capacity in subjects with a high working pace. This can be valuable since it may increase the protection against reactive oxygen radicals.  相似文献   
42.
BACKGROUND: Systemic administration of antibiotics or selective decontamination is frequently used in the prophylaxis and treatment of infections originating from the gastrointestinal flora. In this study, we wanted to compare the protective effect of enteral administration of lactobacilli to gentamicin against severe intra-abdominal infection. METHODS: Male Sprague-Dawley rats underwent cecal ligation and puncture (CLP). Rats were pretreated with saline, Lactobacillus R2LC, and gentamicin. Bacterial growth and endotoxin levels in the blood, reticuloendothelial system (RES)-function, and intestinal transit were determined up to 24 hours after CLP. RESULTS: CLP-provoked bacteremia was significantly reduced by 48% and 55% in lactobacilli- and gentamicin-treated rats, respectively. Notably, CLP-induced endotoxemia was abolished at 12 hours, and reduced by 47% at 24 hours, in rats pretreated with lactobacilli. Gentamicin reduced endotoxin levels provoked by CLP by 86% at 12 hours, but had no effect at 24 hours. Lactobacilli had no effect on the clearance of Escherichia coli (E coli) from the blood, whereas intestinal transit was increased in lactobacilli-treated animals, suggesting that the beneficial effect of Lactobacillus R2LC is not related to an increase of phagocytic capacity but may rather be partly attributable to an enhanced intestinal motility. CONCLUSION: Enteral administration of Lactobacillus R2LC attenuates bacteremia and endotoxemia associated with intra-abdominal infection in rats.  相似文献   
43.
OBJECTIVE: To evaluate the role of target temperature (28 degrees or 34 degrees C) in cardiac surgery on regional oxygenation during hypothermia and rewarming and systemic inflammatory response. DESIGN: Prospective, controlled, and randomized clinical study. SETTING: University hospital. PARTICIPANTS: Elderly patients (mean age 70 +/- 2 years) with acquired heart disease with an anticipated bypass time exceeding 120 minutes (n = 30). INTERVENTIONS: The patients were cooled to either 28 degrees C (n = 15) or 34 degrees C (n = 15). At hypothermia, bypass blood flow was reduced twice from full flow (2.4 L/min/m(2) body surface area [BSA]) to 2.0 L/min/m(2). MEASUREMENTS AND MAIN RESULTS: Hepatic and jugular venous oxygen tension and saturation were higher at 28 degrees C than at 34 degrees C. In comparison with the preoperative values, at 28 degrees C hepatic venous values were higher; whereas at 34 degrees C, they were lower. The reduction of pump blood flow during hypothermia, from 2.4 to 2.0 L/min/m(2)was accompanied by reductions of central, jugular, and hepatic oxygenation at both target temperatures. During rewarming, central and regional venous oxygenation decreased irrespective of the preceding temperature. The decrease was most pronounced in hepatic venous blood, with the lowest individual values <10%. Serum concentrations of C3a and IL-6 increased during hypothermia and increased further during rewarming irrespective of the preceding temperature. CONCLUSION: During cardiopulmonary bypass, hypothermia at 28 degrees C increases regional and central venous oxygenation better than at 34 degrees C. In contrast, venous oxygenation decreases during rewarming irrespective of the preceding temperature. No significant difference in the systemic inflammatory response associated with target temperature was detected.  相似文献   
44.
OBJECTIVE: In the present study, we evaluate our ability to predict surgical procedure repair or replacement using preoperative echocardiography. DESIGN: The reports from transthoracic echocardiographic examinations of 298 patients were analyzed and the gross anatomic lesions and the mechanisms involved were classified into one of three main groups (functional with normal valves, organic degenerated with hypermobile valve or organic degenerated without hypermobility). RESULTS: It was possible to assess the likelihood of repair in 226 patients (76%). The criteria used were institution based and reflect the surgical procedures during the study period (1995-1999). The proportion of patients undergoing repair was 58%. In patients with a high likelihood, repair was performed in 86%. The corresponding figures in the intermediate- and low-likelihood groups were 63 and 23%, respectively. Hypermobility in the posterior leaflet and functional mitral regurgitation led to repair in the majority of patients, while patients with hypermobility in the anterior or both valves more frequently underwent replacement. CONCLUSION: We conclude that it is possible to identify patients with a high likelihood of repair using transthoracic echocardiography.  相似文献   
45.
Leukocyte-endothelium interactions are dependent on a coordinated expression and function of specific adhesion molecules. The objective of the present study was to examine the role of selectin function and leukocyte rolling in tumor necrosis factor-alpha (TNF-alpha)-induced leukocyte adhesion and extravasation in venules in vivo. For this purpose, we used intravital microscopy in the mouse cremaster muscle stimulated for 2-3 h with TNF-alpha intrascrotally. Pretreatment with fucoidan, which inhibits P- and L-selectin, and a P-selectin monoclonal antibody (RB40.34) abolished TNF-alpha-stimulated leukocyte rolling. This great reduction in rolling caused a marked attenuation of firm adhesion and extravascular accumulation of leukocytes. When fucoidan and RB40.34 were administrated after stimulation with TNF-alpha, it was found that leukocyte rolling was greatly reduced whereas the number of firmly adherent leukocytes was completely unchanged, suggesting that the inhibitory effect of blocking P-selectin function on firm leukocyte adhesion and recruitment was due to the reduction in leukocyte rolling along the endothelium. Moreover, pretreatment with a monoclonal antibody against intercellular adhesion molecule-1 (ICAM-1) and a platelet-activating factor (PAF)-receptor antagonist had no effect of TNF-alpha-induced leukocyte rolling and adhesion, indicating that molecules other than ICAM-1 and PAF mediate firm adhesion and recruitment of leukocytes in TNF-alpha-activated tissues. Taken together, our data demonstrate that P-selectin function plays an important role in TNF-alpha-induced inflammatory cell recruitment by mediating leukocyte rolling as a precondition for cytokine-provoked firm adhesion and transmigration in vivo. These findings, thus, suggest that inhibition of P-selectin may be a central target for pharmacological intervention in inflammatory diseases.  相似文献   
46.
The beta-adrenoceptor blocking properties of IPS 339 and propranolol were studied on isolated preparations of trachea and of the slow-contracting soleus muscle from the guinea-pig. Both compounds antagonized the relaxation of the trachea and the depression of subtetanic contractions of the soleus produced by the beta2-selective agonist, terbutaline. On the soleus muscle the pA2-values for IPS 339 and propranolol were similar and close to those obtained for propranolol on the trachea. However, on the trachea the slope of the Schildplot for IPS 339 against terbutaline became less than one and a reliable pA2-value could not be calculated.  相似文献   
47.
A consecutive series of 73 patients treated with intraarterial infusion of 5-fluorouracil (5-FU) for liver metastases from colorectal primary was studied retrospectively using multivariate analysis in order to find determinants of survival. Nontreatment factors had a great impact on variation in survival with liver tumor volume and metastases to lymph glands in the liver hilum as major prognostic determinants. In addition, survival from onset of treatment varied with the interval between the primary operation and the diagnosis of liver metastases. Treatment with intraarterial 5-FU was more effective when administered at long-term (3 months every 6 months) than at short-term (5 days every 6 weeks). Single temporary dearterialization, used as an adjunct to infusion of 5-FU, had a negative impact on length of survival and was followed by a high frequency of complications. The occurrence of hepatic arterial thrombosis was associated with comparatively good prognosis.  相似文献   
48.
Abstract: Colterol, procaterol, sulfonterol, terbutaline and three monophenolic derivatives of terbutaline were examined with respect to their ability to react in vitro on β-adrenoceptors in tissues isolated from guinea-pig. The effects measured were a) relaxation of the tracheal smooth muscle (mostly β2), b) depression of subtetanic contractions of the soleus muscle (β2), and c) increase in the force of the papillary muscle of the left ventricle (β1). Antagonistic effects were measured against isoprenaline as an agonist. The compounds studied showed a wide variation in selectivity, potency and intrinsic activity. All agonists showed a pronounced β2-selectivity, in general characterized by a higher intrinsic activity at β2- than at β1-adrenoceptors, while differences in affinity, as judged from the pA2-values were small. Partial agonists, such as sulfonterol, which did not cause a complete relaxation of a moderately contracted tracheal muscle, produced identical concentration-response curves from the trachea and soleus muscle. It is concluded that partial agonism at β1-adrenoceptors is an important factor for functional selectivity of β2-adrenoceptor agonists. On the other hand there seems to be no useful differences between the maximum effect elicited by a partial β2-adrenoceptor agonist on the skeletal muscle as compared with airway smooth muscle.  相似文献   
49.
Major liver resection: perioperative course and management   总被引:5,自引:0,他引:5  
This report investigates the perioperative course in 81 consecutive major liver resections, performed mainly because of primary liver cancer or colorectal liver secondaries. The liver was resected transabdominally with or without prior ligation of hilar structures. Intravenous nutrition consisted of 10% dextrose alone and was started preoperatively. Albumin or plasma was used rarely and only in conjunction with massive intraoperative transfusion of blood. Major complications, including four operative deaths (4.9%), consisted of bleeding and/or infection in eight (10%) patients and overt liver failure in two patients (2%) and occurred only after right and extended right lobectomies. Intraoperative blood loss was significantly larger in patients with postoperative complications than in patients with an uneventful postoperative course. The direct parenchymal approach was associated with a shorter operative time and an unchanged intraoperative bleeding. Coagulopathy and hypoalbuminemia did not cause any problems. Blood glucose levels were stable, and no patient suffered from hypoglycemia. It is concluded that major liver resection should be based on prevention of intraoperative bleeding and that preresection ligation of hilar structures offers no advantage in this respect. Infusion of hypocaloric glucose solutions should be started the day before operation, and routine administration of other nutrients does not seem necessary.  相似文献   
50.

Introduction  

To achieve any possible positive effect on the intestinal mucosa cells it is important that probiotics adhere tightly onto the intestinal mucosa. It has been shown in healthy volunteers that Lactobacillus plantarum 299v (Lp 299v) (DSM 9843), a probiotic bacterium, given orally in a fermented oatmeal formula adheres onto the intestinal mucosa, but whether this also occurs in critically ill patients is unknown.  相似文献   
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