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51.
OBJECTIVE: Treatment with erythropoiesis-stimulating factors (ESFs) can ameliorate anemia associated with cancer and chemotherapy. However, half of anemic cancer patients do not respond even to high doses. To determine factors that are predictive of a treatment response, a multicenter, prospective study was performed. PATIENTS AND METHODS: Investigated factors were baseline erythropoietin, reticulocytes and soluble transferrin receptor (sTfR) after 2 weeks, and reticulocytes and hemoglobin after 4 weeks. Anemic patients with solid tumors received 150 microg/week of darbepoetin concomitantly with chemotherapy. The dose was doubled if hemoglobin did not increase by >1 g/dl after 4 weeks. Patients were considered responders if hemoglobin increased by >or=2 g/dl or reached a level >or=12 g/dl within 8-12 weeks. RESULTS: In total, 196 patients were enrolled; 61% of the intention-to-treat (ITT) and 68% of the per-protocol population were responders. In the ITT population, the hemoglobin increase after 4 weeks indicated an 11-fold higher chance of response (odds ratio, 11.0; 95% confidence interval [CI], 5.1-23.6; sensitivity, 88%; specificity, 60%). In a multiple logistic regression model including all factors, the area under the receiver operating characteristic curve was 0.78 (95% CI, 0.71-0.84). The combination of sTfR after 2 weeks and hemoglobin after 4 weeks was as predictive as the combination of all five tested factors. CONCLUSION: So far, an early hemoglobin increase remains the single most predictive factor for response to ESF treatment. In contrast to anemic patients with lymphoproliferative malignancies, serum erythropoietin had little predictive value in patients with solid tumors.  相似文献   
52.
Background Negative surgical margins minimize the risk of local recurrence after breast-conserving surgery. Intraoperative frozen section analysis (FSA) is one method for margin evaluation. We retrospectively analyzed records of patients who received breast-conserving therapy with intraoperative FSA of the lumpectomy cavity to assess re-excision rates and local control. Methods Records were retrospectively reviewed for individuals who underwent breast-conserving surgery for ductal carcinoma in situ (DCIS) or invasive carcinoma between 1993 and 2003. Inclusion criteria were a minimum of 2 years follow-up and intact tumor at the time of operation. The major outcome measure was local recurrence. The Kaplan-Meier test was used to evaluate local recurrence rates between groups. Results 290 subjects with an average age of 57.2 years (range 27–89) underwent 292 lumpectomies with FSA. 11.3% had DCIS, 73.3% had infiltrating ductal, 5.8% had infiltrating lobular, and 9.6% exhibited other forms of invasive carcinoma. 70 subjects underwent additional resection at the time of breast surgery, 16 underwent subsequent re-excision, and 17 underwent subsequent mastectomy. At a median follow-up of 53.4 months (range 5.8–137.8), there were six local recurrences (2.74%) in patients who had breast-conserving procedures and two local recurrences in patients who underwent mastectomy. There were no statistically significant associations among local recurrence rate, tumor size, nodal status, or overall stage. Local recurrences were higher in patients with DCIS compared with invasive carcinoma, and tumors >2cm. Conclusions Intraoperative FSA allows resection of suspicious or positive margins at the time of lumpectomy and results in low rates of local recurrence and re-excision. The low local recurrence rate reported here is comparable to those reported with other margin assessment techniques.  相似文献   
53.
一阶导数差示脉冲极谱法的建立及在药物分析中的应用   总被引:11,自引:0,他引:11  
梁云爱  张天民 《药学学报》1992,27(2):135-138
本文研究了一阶导数差示脉冲极谱法,并将其运用于扑尔敏、氟哌啶醇、维生素B6及其制剂的定量分析中。方法简便、快速、灵敏、结果准确。  相似文献   
54.
Karkouti  K  Beattie  WS  Dattilo  KM  McCluskey  SA  Ghannam  M  Hamdy  A  Fedorko  L  Yau  TM 《Journal canadien d'anesthésie》2005,52(1):A64-A64
Canadian Journal of Anesthesia/Journal canadien d'anesthésie -  相似文献   
55.
56.
Summary: Oral ofloxacin has been successfully used in our centres for the primary treatment of peritonitis complicating continous ambulatory peritoneal dialysis (CAPD). In view of the progressive rise in the resistance rate to ofloxacin among peritoneal bacterial isolates, a study was conducted to determine if oral ofloxacin remains a viable first line treatment for CAPD peritonitis in our centres and if the result can be improved by changing from an oral to an intraperitoneal (i.p.) route. In patients on three 2 L daily CAPD exchanges, ofloxacin given at the i.p. dosage of 200 mg loading followed by 25 mg/L of peritoneal dialysate achieved overnight trough peritoneal levels which are at least four times the minimal 90% inhibitory concentration (MIC90) of most bacterial pathogens without significant accumulation in the systemic circulation. This i.p. dosage was therefore chosen for the clinical study and the result was compared to that using ofloxacin given in the oral dosage of 400 mg loading followed by 300 mg once daily as maintenance. of all the recruited episodes, 35 were eligible for analysis. the overall primary cure rate including primary failures and relapses was 55.6% (10/18) in the oral treatment group and 70.6% (12/17) in the i.p. treatment group. the corresponding figures for gram positive bacterial (g +) infections were 36.4% and 50%, for gram negative bacterial (g -) infections were 66.7 and 80% and for culture negative infections were 75 and 80%. In culture positive cases, all treatment failures were due to resistant infections which were observed in 42.3% of all bacterial isolates, 47.1% of g + isolates and 33.3% of g - isolates. Due to the high background level of bacterial resistance among our CAPD population, ofloxacin monotherapy given either by the oral or the i.p. route can no longer be recommended for the primary treatment of CAPD peritonitis.  相似文献   
57.
Quality systems and total process control in blood banking   总被引:3,自引:0,他引:3  
Blood banking has dramatically changed in the past few years. Is the old business hierarchy and medical model for management still workable? How do we want to organize our work today for success in the future? Implementation of quality systems may seem overwhelmingly complex at this time to many blood banking establishments. However, by methodically adhering to the requirements of organization development described in this review, blood centers can achieve goals of quality improvement and TPC. The FDA and the pharmaceuticals and medical device industries have set the direction and provided guidance to blood establishments. The AABB, American Society for Quality Control, the American Society for Training and Development, and numerous other professional organizations can contribute information and materials. The FDA's document on quality assurance and the CFR are the basic texts guiding the approach presented in this paper. The organization's structure and processes may need to be reengineered to meet the requirements of a culture based on quality and process control.  相似文献   
58.
We report the beneficial effects of enzyme replacement therapywith mannose-terminated human glucocerebrosidase (‘Ceredase’)in a patient suffering from transfusion-dependent bone marrowfailure due to Gaucher's disease. Treatment with low-dose enzymeinfusions, given twice weekly, rapidly reversed the haematopoieticfailure and incapacitating skeletal disease. It appears likelythat prior splenectomy favourably influenced the response tothis therapy.  相似文献   
59.
BACKGROUND: Since screening for antibody to hepatitis C virus (HCV) was introduced in 1990, posttransfusion hepatitis has been reduced to nearly background levels. This has led to reconsideration of the value of testing donated blood for elevated alanine aminotransferase (ALT). The contribution of ALT testing in detecting seronegative infection was evaluated by the performance of polymerase chain reaction (PCR) for hepatitis B virus (HBV) or HCV in plasma from ALT-elevated blood units. STUDY DESIGN AND METHODS: Testing was performed on 375 units of plasma, derived from an equivalent of 47,500 blood donations, with a highly sensitive hemi-nested PCR procedure. Using a triplet of primers directed at the conserved regions of HBV DNA and 5'-noncoding regions of HCV RNA, the hemi-nested PCR assay can reliably amplify 10 viral molecules to levels detectable in ethidium bromide-stained agarose gels. Pools of plasma from groups of four donors were screened with hemi-nested PCR. For any reactive pools, the plasma from individual donors was retested twice on different aliquots. RESULTS: Two of 375 units, both with midrange ALT elevation, were repeatedly reactive in hemi-nested PCR (one each for HBV DNA and HCV RNA). However, samples from the two suspect donors tested 9 and 5 months later revealed no seroconversion, elevated ALT, or viral genomes in hemi-nested PCR. CONCLUSION: The lack of confirmed HBV or HCV infection in this study representing an estimated 47,500 voluntary blood donations suggests that routine ALT testing for further prevention of posttransfusion hepatitis after exclusion of HBV- and/or HCV-seropositive blood may be superfluous.  相似文献   
60.
van 't Veer  C; Hackeng  TM; Delahaye  C; Sixma  JJ; Bouma  BN 《Blood》1994,84(4):1132-1142
The procoagulant subcellular matrix of stimulated endothelial cells that contains tissue factor (TF) was used to investigate the mechanism by which TF pathway inhibitor (TFPI) inhibits thrombin formation initiated by TF/factor VIIa (FVIIa) under flow conditions. Purified coagulation factors VII, X, and V and prothrombin were perfused at a wall shear rate of 100 s-1 through a flow chamber containing a coverslip covered with matrix of cultured human umbilical vein endothelial cells. This resulted in a TF- and FVII-dependent FXa and thrombin generation as measured in the effluent at the outlet of the system. Inhibition of this TF/FVIIa-triggered thrombin formation by TFPI purified from plasma was dependent on the amount of TF present on the endothelial cell matrix. The rate of prothrombinase assembly and steady-state levels of thrombin formation were decreased by TFPI. Because persistent albeit decreased steady-state levels of thrombin formation occurred in the presence of TFPI, we conclude that plasma- TFPI does not inhibit FXa present in the prothrombinase complex. The addition of FIX and FVIII to perfusates containing FVII and FX increased the FXa generation on endothelial matrices, and counteracted the inhibition of thrombin formation on endothelial cell matrices by TFPI. Our data provide further evidence for the hypothesis that the rapid inactivation of TF/FVIIa by TFPI in combination with the absence of either FVIII or FIX causes the bleeding tendency of patients with hemophilia A or B.  相似文献   
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