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781.

Purpose  

This clinical trial reports the use of hydroxyethyl starch (HES70/0.55/4) at very high dosages during surgery. HES70/0.55/4 has the lowest molecular weight among all HES products, and thus may have the least side effects. This observational retrospective study clarified the effects of high-dose HES70/0.55/4 on coagulation and renal function up to 1 month after massive bleeding during surgery.  相似文献   
782.
Abstract: A 59-year-old woman was admitted to our hospital because of heart failure. In 1988, she underwent aortic valve replacement with an Omnicarbon valve and mitral valve replacement with a bioprosthetic valve. She was doing well until July in 1996 when she developed heart failure. Echocardiography revealed massive mitral valve regurgitation, and cinefluoroscopy showed implanted Omnicarbon valve dysfunction with a leaflet opening angle of 35 degrees. At reoperation, it was revealed that pannus formation prevented the valve from functioning well. The pannus was resected through the major orifice, and the leaflet was rotated toward the right anterolateral orientation. The worn bioprosthetic valve was replaced with a mechanical one. Postoperative cinefluoroscopy of the rotated Ominicarbon valve showed the opening angle to be 61 degrees.  相似文献   
783.
Phosphodiesterases in the vascular system.   总被引:2,自引:0,他引:2  
Cyclic adenosine 3',5'-monophosphate (cAMP) and cyclic guanosine 3',5'-monophosphate (cGMP) are second messengers involved in the intracellular signal transduction of a variety of extracellular stimuli in several tissues. In the vascular system, these nucleotides play important roles in the regulation of vascular tone and in the maintenance of the mature contractile phenotype in smooth muscle cells. Given that cyclic nucleotide signaling regulates a wide variety of cellular functions, it is not surprising that cyclic nucleotide phosphodiesterases (PDEs). In paticular, the accumulating data showing that there are a large number of different PDE isozymes have triggered an equally large increase in interest about these enzymes. At least 11 different gene families of PDEs are currently known to exist in mammalian tissues. Most families contain several distinct genes, and many of these genes are expressed in different tissues as functionally unique alternative splice variants. This article reviews many of the important aspects about the structure, cellular localization, and regulation of each family of PDEs. Particular emphasis is placed on new information obtained in the last few years about vascular disease. The development of novel methods to deliver more potent and selective PDE inhibitors to individual cell types and subcellular locations will lead to new therapeutic uses for this class of drugs in diseases of the vascular system.  相似文献   
784.
A 73-year-old woman evidencing an abnormal shadow on chest X-ray film since 1993 was admitted after a tumor of the left 8th rib was diagnosed in 2001. Computed tomography showed a low-density mass with coarse calcification arising from the left 8th rib and protruding into the abdominal cavity. The tumor was diagnosed as low-grade chondrosarcoma by incision biopsy and was resected together with the left 7th, 8th, and 9th ribs. The chest wall was reconstructed using Marlex mesh. Histological findings were compatible with Grade I chondrosarcoma. The patient had a long clinical course without distant metastasis thanks to the tumor's low malignancy.  相似文献   
785.
The efficacy and safety of fibrinolysis and subsequent transluminal (FAST) therapy were evaluated in 195 patients with acute myocardial infarction (AMI) for the early achievement of thrombolysis-in-myocardial-infarction grade 3 (TIMI-3) flow in the infarct-related artery. Intravenous thrombolysis using the optimal dose of a thrombolytic agent was initiated immediately after arrival in the emergency room, followed by coronary angiography and adjuvant percutaneous coronary intervention. A comparison of the thrombolysis alone (n=83) and thrombolysis plus intervention (n=112) groups showed significant differences in the time interval from hospital arrival to achievement of TIMI-3 flow (66.2+/-23.7 vs 111.6+/-29.6 min, p<0.0001), creatine kinase-MB release (295+/-201 vs 468+/-322 U/L, p=0.0003) and peak troponin T (23.6+/-16.9 vs 38.9+/-25.9 ng/ml, p<0.0001). No significant differences were observed in either 30-day mortality or complications. The TIMI-3 flow at the initial angiography was significantly higher with a single bolus of mutant tissue-type plasminogen activator (t-PA) monteplase than with an accelerated infusion of t-PA (60% vs 32%, p=0.005). In conclusion, the early restoration of TIMI-3 flow by FAST therapy reduced the degree of myocardial damage with a low risk of complications. TIMI-3 flow was achieved at an earlier stage with monteplase and this agent may be beneficial in the FAST therapy.  相似文献   
786.
Fenoterol, a beta2-adrenoceptor selective agonist, belongs to the arylethanolamine class. To understand the receptor subtypes responsible for beta-adrenoceptor-mediated relaxation of guinea pig taenia caecum, we investigated the effect of fenoterol. Fenoterol caused concentration-dependent relaxation of the guinea pig taenia caecum. Propranolol, bupranolol and butoxamine produced shifts of the concentration-response curve for fenoterol. Schild regression analyses carried out for propranolol, butoxamine and bupranolol against fenoterol gave pA2 values of 8.41, 6.33 and 8.44, respectively. However, in the presence of 3 x 10(-4) M atenolol, 10(-4) M butoxamine and 10(-6) M phentolamine to block the beta1-, beta2- and a-adrenoceptor effects, respectively, Schild regression analysis carried out for bupranolol against fenoterol gave pA2 values of 5.80. These results suggest that the relaxant response to fenoterol in the guinea pig taenia caecum is mediated by both the beta2- and the beta3-adrenoceptors.  相似文献   
787.
788.
OBJECTIVE: Ischemia-reperfusion injury is a major factor in the early phase of lung transplantation. We hypothesized that aprotinin, a nonspecific serine protease inhibitor, attenuates ischemia-reperfusion lung injury by inhibiting the inflammatory response and suppressing NADPH oxidase. METHODS: We used an isolated rat lung model to test the above. A Control group was immediately perfused with fresh heparinized allogeneic blood after lung harvest without an ischemic period. Study lungs were flushed with low-potassium dextran (LPD) solution and stored for 18h at 4 degrees C then divided into two groups: the LPD group was flushed with LPD solution only, and the LPD+A group was flushed with LPD solution +200KIU/ml aprotinin. Lungs in all three groups were then reperfused with fresh heparinized allogeneic blood for 120min at 37 degrees C. RESULTS: Throughout reperfusion, PO(2) levels in the LPD+A group were similar to those in the Control group; although in the LPD group, PO(2) levels were significantly lower (P<0.05). Tissue MDA levels were significantly higher in the LPD group than the Control and LPD+A groups (P<0.05). IL-8 levels were significantly higher in the LPD group than the Control group (P<0.05), while in the LPD+A group they were similar to those in the Control group. Histological evaluation showed interstitial edema accompanied by neutrophil extravasation in the LPD group, whereas this effect was modest in the LPD+A group. An additional study of ischemia-reperfusion in an alveolar macrophage culture showed that the activitvation of NADPH oxidase, and translocation of p47(phox) from the cytosol to the membrane were suppressed in aprotinin group. CONCLUSIONS: Aprotinin attenuates ischemia-reperfusion lung injury by inhibiting the early inflammatory response, neutrophil extravasation and the production of oxygen free radicals through inhibition of the activation of the NADPH oxidase. The inhibition of p47(phox) translocation in alveolar macrophage seemed involved in this mechanism of aprotinin.  相似文献   
789.
OBJECTIVE: The purpose of this study was to establish selection criteria for intentional limited resection in patients with peripheral lung cancer. METHODS: Six hundred eighty-nine cases of cT1N0M0 peripheral non-small cell lung cancer were divided into groups according to maximum tumor diameter. The cases in each group were examined for histopathological invasive factors, and the results of a pilot study of intentional limited resection were assessed. RESULTS: The positive rate of invasive factors was 30.8% among the patients with tumors 2 cm or less in diameter, and significantly lower than the 44.0% noted in those whose tumor diameter was in the 2.1-3.0 cm range. The positive rate was significantly lower in 90 patients with type A or B adenocarcinoma, and none of these patients developed postoperative recurrence. In 24 of these 90 patients, the tumor diameter was in the 2.1-3.0 cm range. The 5-year survival rate in the 74 patients with pT1N0M0 and tumors 2 cm or less in diameter who underwent limited resection was 89.1%. CONCLUSIONS: We attempted to establish selection criteria for limited resection, with the aim of obtaining survival rates that was comparable to those obtained after lobectomy. The selection criteria established in this study are: 1, cT1N0M0 peripheral non-small cell lung cancer; 2, maximum tumor diameter 2 cm or less on diagnostic images, but a tumor diameter in the range of 2-3 cm in adenocarcinoma of Noguchi type A or B cases; 3, limited resection feasible based on tumor location.  相似文献   
790.
BACKGROUND: Although cryopreserved tissues are used clinically, the effects of cryopreservation on antigenicity leading to immune and non-immune responses are not well known. METHODS: We investigated the change of inflammatory effects of cryopreserved tissue by using spleen and aortic allografts from Class I antigen-disparate B6.C-H-2(bm1) (bm1; K(bm1), IA(b), D(b)), Class II antigen-disparate B6.C-H-2(bm12) (bm12; K(b), IA(bm12), D(b)) and Class I and Class II antigen-disparate (bm1 x bm12)F1 (K(bm1 x b), IA(b x bm12), D(b)) mice against C57BL/6 Cr Slc (B6; H-2(b)) mice. Cryopreservation was done in a programmed freezer and cryopreserved tissues were kept in the vapor phase of liquid nitrogen for 2 weeks and thawed at room temperature. RESULTS: Cryopreserved B6 spleen cells expressed almost the same levels of Class I (K(b) and D(b)) and Class II (IA(b)) antigens as observed in fresh B6 spleen cells. Cryopreserved bm1 and bm12 spleen cells had the same stimulator activities in mixed-lymphocyte reaction (MLR) and cytotoxic T-lymphocyte (CTL) assays compared with fresh bm1 and bm12 spleen cells, respectively. To elucidate the effects of cryopreserved tissues on immune response of recipients, descending aortas of (bm1 x bm12)F1 mice were implanted into the right common carotid artery of B6 (H-2(b)) mice with the cuff technique and the reactivities of recipient B6 mice against Class I antigen-disparate bm1 antigens and Class II antigen-disparate bm12 antigens were examined 4 weeks after implantation. In both MLR and CTL assays against bm1 or bm12 antigens, anti-donor reactivities were augmented and there was no significant difference between B6 mice grafted with fresh aortic allografts and those grafted with cryopreserved ones. Histologic analysis showed that mild infiltration of mononuclear cells into the adventitia was observed in both fresh and cryopreserved aortic allografts. The fibrous change was observed more strongly in cryopreserved aortic allografts compared with fresh aortic allografts. CONCLUSIONS: Cryopreservation has no effect on eliciting immune responses to Class I or Class II alloantigens, but has some effect on promoting fibrous change.  相似文献   
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