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31.
BACKGROUND: The purpose of this study was to search for a more effective transfusion-monitoring system than the existing system of retrospective peer review. STUDY DESIGN AND METHODS: This research used a study-control, preintervention and postintervention design, to evaluate the effectiveness of a prospective physician self-audit transfusion-monitoring system that functioned without the direct involvement of transfusion service physicians. This research also evaluated the effectiveness of issuing to physicians a memo with transfusion guidelines. Three process indicators were used to assess physician behavior at various stages of the blood-ordering process: 1) the number of crossmatches ordered per admission, 2) the transfusion-to- crossmatch ratio, and 3) the number of blood units returned to the laboratory after physician self-auditing. The study used two outcome indicators to reflect overall blood utilization: 1) the percentage of patients who received red cell transfusions and 2) the number of blood units transfused per recipient each month. RESULTS: The prospective physician self-audit system implemented at the study hospital did not reverse physician transfusion decisions, and the process of issuing to physicians a memo with transfusion guidelines at the control hospital failed to reduce blood usage. However, a transient reduction in blood utilization was observed at the study hospital. CONCLUSION: The reduction was hypothesized to be due to a Hawthorne effect, in which observed behavior is affected by the subject's awareness of the research study.  相似文献   
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Promyelocytic leukemic HL-60 cells were incubated with different fatty acids. Arachidonic acid (AA; 20:4, n-6) and eicosapentaenoic acid (EPA; 20:5, n-3) were the most potent inhibitors of proliferation in a dose- dependent way. Retinoic acid (RA) was used as a positive control. Inhibitors of cyclooxygenase and lipoxygenase or addition of antioxidants did not influence the effect of EPA or AA on cell proliferation. Increased capacity to generate superoxide anions after phorbol ester treatment and a reduced serglycin messenger RNA level in cells treated with AA or EPA indicated that these fatty acids induced differentiation in HL-60 cells similar to that induced by RA. However, down-regulation of the c-myc mRNA level, also typical for differentiation with RA in HL-60 cells, was not observed in cells incubated with AA or EPA. Flow cytometric analyses showed that in cultures incubated with AA or EPA, the proportion of cells in the G1 phase of the cell cycle increased. Similar effects were observed with RA. By flow cytometry and light scatter analyses it could be shown that AA made 8% of the cells apoptotic and 7% necrotic. The corresponding numbers were 21% and 10% for RA-treated cells, and 19% and 32% for EPA- treated cells. The present study shows that AA and EPA reduce the proliferation rate of HL-60 cells. This is mediated by mechanisms independent of eicosanoids or lipid peroxidation products and is due to effects both on apoptosis/necrosis and cell differentiation.  相似文献   
33.
Human T-cell lymphotropic virus I (HTLV-I)-induced adult T-cell leukemia (ATL) cells constitutively express interleukin-2 (IL-2) receptors identified by the anti-Tac monoclonal antibody (MoAb), whereas normal resting cells do not. This observation provided the scientific basis for a trial of intravenous anti-Tac in the treatment of nine patients with ATL. The patients did not suffer untoward reactions and did not have a reduction in the normal formed elements of the blood, and only one of the nine produced antibodies to the anti-Tac MoAb. Three patients had transient mixed, partial, or complete remissions lasting from 1 to more than 8 months after anti-Tac therapy, as assessed by routine hematologic tests, immunofluorescence analysis of circulating cells, and molecular genetic analysis of HTLV-I provirus integration and of the T-cell receptor gene rearrangement. The precise mechanism of the antitumor effects is unclear; however, the use of a MoAb that prevents the interaction of IL-2 with its receptor on ATL cells provides a rational approach for the treatment of this malignancy.  相似文献   
34.
BackgroundEndoscopy is required for formal diagnosis of many upper gastrointestinal (UGI) conditions including oesophageal cancer (OC). There is a paucity of data on endoscopy findings in East Africa as access to testing is challenging for patients. We describe the findings of 10 years of UGI endoscopy in Mbale Regional Referral Hospital (MRRH).MethodRecords of patients that underwent UGI endoscopy in MRRH, November 2009 – March 2019 were retrospectively analysed. Indication, macroscopic findings, histology and patient demographics were retrieved. Sub-group analyses were performed on those with a histological diagnosis of oesophageal cancer.Results833 eligible patients received single UGI procedures during the study period. Mean age was 54.8 years, range 16-93 years and 56.9% of patients were male. The main indication was dysphagia (42%) and the most common findings OC (34%) and gastritis (28%). 151 patients had histologically proven OC with a median age of 60 years and a 2:1 male to female ratio. 145/151 (96%) of samples tested revealed squamous cell carcinoma (SCC).ConclusionThose undergoing endoscopy in MRRH are most commonly male patients presenting in their 5th decade with dysphagia. There is a high proportion of significant findings including gastritis, peptic ulcer disease, and oesophageal cancer.  相似文献   
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36.
Human red cells (RBCs) were collected in CPDA-1 and then freeze-dried in lyoprotective solution. The lyophilized RBCs were then stored at -20 degrees C for 7 days. At the end of the storage period, the lyophilized RBCs were rehydrated and washed in dextrose saline. The washed, reconstituted, lyophilized RBCs were resuspended in final wash solutions of ADSOL, CPDA-1, or a special additive solution containing glucose, citrate, phosphate, adenine, and mannitol, and then they were stored at 4 degrees C for an additional 7 days. The main purpose of this study was to determine whether human RBCs can be lyophilized in such a manner that normal metabolic, rheologic, and cellular properties are maintained during rehydration and subsequent storage in standard blood bank preservative solutions. Our results show that reconstituted, lyophilized RBCs maintained levels of ATP, 2,3 DPG, lactate, and cellular properties that are equal to or better than those in control nonlyophilized RBCs stored for a comparable period in CPDA-1. Reconstituted, lyophilized RBCs stored at 4 degrees C after rehydration also show better maintenance of ATP, 2,3 DPG, and lactate than do control RBCs stored in the same preservative solutions for comparable periods.  相似文献   
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38.
目的观察自体细胞因子诱导杀伤细胞(CIK细胞)治疗HBVDNA阳性肝硬化患者的近期疗效。方法33例HBVDNA阳性肝硬化患者给予CIK细胞治疗,在体外培养前后以及回输体内后检测CD3^+、CD3^+CD4^+、CD3^+CD8^+、CD3^+CD56^+、CD25^+细胞以及mDC和pDC。比较治疗前后病毒学指标及肝脏功能的变化。结果培养结束以及回输体内后,CD3^+细胞、CD3^+CD8^+细胞、CD3^+CD56^+细胞较培养前显著升高,mDC和pDC在回输后也明显增高。12例患者HBVDNA阴转,4例患者拷贝数下降大于2个log。在14例HBeAg阳性患者中有10例阴转,2例出现HBeAb转换。肝脏功能较治疗前有所好转。所有患者均能耐受治疗。结论ClK细胞可明显提高免疫效应细胞数量,具有一定的抗病毒效果,毒副作用低,对患者伤害小,安全性高,不良反应小,经过护理干预,患者的症状和体征得到改善,取得了显著疗效。  相似文献   
39.
Rationale Evidence on sequential trial with atypical antipsychotics has been scarce. Objectives We conducted an algorithm-based antipsychotic pharmacotherapy. Materials and methods In this open-label study, patients with schizophrenia (DSM-IV) were treated with antipsychotic monotherapy, step-by-step, with each trial lasting up to 8 weeks. At baseline, they were highly symptomatic to score more than 54 in the total Brief Psychiatric Rating Scale (BPRS1–7) score. When the posttreatment BPRS score was above 70% of the baseline, they were subsequently treated with another and up to three atypicals. Basically, anticholinergics were prohibited, and only adjunctive allowed was lorazepam. The secondary endpoint was a clinical status good enough to be discharged for 66 inpatients and a successful continuation therapy with the same antipsychotic agent for more than 6 months for 12 outpatients. Results Three groups of 26 patients each were randomized to Olanzapine, Quetiapine, or Risperidone. Thirty-nine (50%) responded to the first agent (Olanzapine16, Quetiapine9, Risperidone14), and 14 responded to the second. Only two showed response to the third, and 16 failed to respond to all three antipsychotics, with only 7 dropouts. Overall, there were 22 Olanzapine, 14 Quetiapine, and 19 Risperidone responders. Based on the secondary outcome, 20 Olanzapine-treated (average maximum dose, 15.4 mg), 10 Quetiapine-treated (418 mg), and 20 Risperidone-treated (4.10 mg) patients responded. The difference in response as the first choice was significant (p < 0.05). Relative doses of those failing to respond were comparable (Olanzapine 18.3 mg, Quetiapine 564 mg, Risperidone5.47 mg). Extrapyramidal symptoms did not change significantly. Conclusions When the first atypical antipsychotic is inadequate, switching to the second is worth trying, although some remain treatment-refractory. Quetiapine may be inferior to Olanzapine and Risperidone in symptomatic patients.  相似文献   
40.
目的:探讨敲低PI3Kp85α表达对人乳腺癌细胞系MCF-7细胞生长的影响和机制.方法:用靶向PI3Kp85α的siRNA转染人乳腺癌细胞系MCF-7,使用Real-time PCR法鉴定转染PI3Kp85α表达水平;MTT法评价PI3Kp85α siRNA对乳腺癌细胞系MCF-7生长的影响;流式细胞术检测转染后细胞周期分布和凋亡;采用免疫荧光染色及Western blot方法观察IA型PI3K/AKT通路主要成员的表达.结果:Real-timePCR结果显示PI3Kp85α siR-NA转染导致PI3Kp85α表达下调;MTT结果显示PI3Kp85α siRNA转染抑制肿瘤细胞生长;流式细胞术检测可见PI3Kp85α siRNA转染组细胞周期存在G_0/G_1期阻滞而且凋亡率显著高于对照组与空载体组(F=19.255,P=0.002).结论:应用PI3Kp85α siRNA转染人乳腺癌细胞系MCF-7细胞,可抑制其增殖和诱导细胞凋亡,因此PI3Kp85α可以作为人乳腺癌基因治疗的候选靶点.  相似文献   
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