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41.
目的:检测维甲酸(Retinoic acid,RA)诱导小鼠胚胎腭裂模型中胎鼠舌体发育过程中肌相关 microRNAs(MyomiRs)、成肌调节因子(Myogenic regulatory factors,MRFs)以及 Pax 基因的表达变化,探究 MyomiRs 在舌肌分化过程中的调控作用,推测RA 致胎鼠腭裂伴发舌异常的可能机制。方法:建立 RA 诱导小鼠胚胎腭裂模型,分别在 E13.5、E14.5、E15.5收集胎鼠舌体组织,用 SYBR GreenⅠ实时定量 PCR 检测舌体中 MRFs 和 Pax 基因的表达;用 TaqMan 探针实时定量 PCR 检测舌体中 MyomiRs 的表达。结果:胎鼠舌体发育过程中,正常组 miR-1和 miR-206相对表达量均持续上升,RA 诱导组二者变化趋势与正常组相似,但相对表达量均低于正常组,miR-1的结果在 E14.5和 E15.5具有统计学意义(P <0.01),miR-206的结果在 E13.5具有统计学意义(P <0.05)。正常组和 RA 诱导组胎鼠舌体中 MyoD 和 Myf5相对表达量都在 E14.5达到峰值,随后下降。RA 诱导组 MyoD 的表达在 E14.5显著低于正常组(P <0.05),在 E15.5显著高于正常组(P <0.01);RA 诱导组 Myf5的表达在 E15.5显著低于正常组(P <0.05)。正常组和 RA 诱导组胎鼠舌体中 Pax3表达均在 E14.5达到峰值,Pax7表达均在 E15.5达到峰值。RA 诱导组 Pax3的表达在 E14.5显著高于正常组(P <0.05);Pax7的表达则在 E13.5显著高于正常组(P <0.01)。结论:在舌肌分化过程以及RA 诱导腭裂胎鼠的舌发育异常中,miR-1/miR-206与 Pax3/Pax7及 Myf5/MyoD 的表达趋势具有相关性。RA 可能通过下调 miR-1/miR-206而靶向上调 Pax3/Pax7,进而下调 MyoD /Myf5表达,从而抑制舌肌分化,导致舌肌发育异常。  相似文献   
42.
INTRODUCTION: Patients with albinism have varying degrees of reduced vision, strabismus, iris transillumination, nystagmus, fundus hypopigmentation, and foveal hypoplasia. High refractive errors are common, but reduced vision persists due to nonrefractive factors, causing reluctance by some clinicians to prescribe spectacles. We sought to evaluate the effect of spectacle correction of refractive error on clinical findings and recorded compliance with refractive corrections, as little detailed data exist. METHODS: We prospectively examined 35 consecutive patients with albinism for whom glasses had been prescribed to determine if objective improvement in recognition visual acuity (VA), strabismus, anomalous head posture (AHP), fusion, or stereoacuity occurred with refractive correction. Parents or patients reported compliance with glasses wear (excellent: >75% of awake hours; good: 50-75% of awake hours; fair: 26-50% of awake hours; poor: <25%). RESULTS: Median age was 9.5 years (range: 3 to 30). Median refractive correction was 1.875 D spherical equivalent (range: -9.75 to +8.88 D). Glasses wear was initiated at a median age of 14 months (range: 3 months to 14 years). Mean binocular VA at distance was 20/80.9 corrected and 20/107.6 uncorrected ( P < 0.001). Mean VA at near was 20/28.4 corrected and 20/41 uncorrected ( P < 0.001). Mean strabismic deviation was 7.2 PD with glasses and 10.0 PD without glasses at distance ( P = 0.006) and 10.8 PD with glasses and 14 PD without glasses at near ( P = 0.042). Mean AHP at distance was 8.3 degrees with glasses and 7.3 degrees without glasses at distance ( P = 0.327) and 4.7 degrees both with and without glasses at near ( P = 0.308). Twenty-one patients had fusion with or without glasses, two had fusion only with glasses, and one patient had fusion only without glasses. The other patients did not have any detectable degree of fusion. Twenty-seven individuals had no stereoacuity with or without glasses, five had gross stereoacuity of 3000 seconds of arc both with and without glasses, and three had gross stereoacuity only while wearing glasses. Compliance was excellent in 29 patients, fair in four, and poor in two. CONCLUSION: This prospective study showed a significant improvement in corrected VA and alignment in persons with albinism, despite overall subnormal acuity. Some individuals also experienced improvement in binocular alignment and AHP. Compliance with spectacles was generally good. Therefore, refractive correction should be encouraged in persons with albinism as improvement in visual function is likely to occur.  相似文献   
43.
目的:筛选一株优良的抗生素产生菌。方法:通过人为诱变来动摇产生菌原有的严密控制机制。结果:得到一种抗生素生物合成能力异常的突变株。结论:此方法可过量合成人们所期望的抗生素。  相似文献   
44.
目的:考察盐酸特拉唑嗪胶囊的稳定性。方法:通过影响因素(强光照射、高温、高温),加速和留样考察实验,以含量为测定指标,考察胶囊的含量变化。结果:在温度40℃、60℃、光照3500LX及RH75%等因素影响下,胶囊的含量无明显变化。结论:在25℃时,通过经典恒温加速试验推测盐酸特拉唑嗪胶囊的失效期为2年。  相似文献   
45.
BACKGROUND: 13C breath test analysis requires accurate 13CO2 measurements. AIM:: To perform a multicentre study to evaluate the repeatability and reproducibility of breath 13CO2 analysis. METHODS: Two series of 25 paired randomly coded tubes (each consisting of 23 13CO2-enriched breath samples and two samples of standard reference pure CO2 with certified delta 13CPDB) were sent to participating centres for 13CO2 measurement. Each series of tubes was analysed 10 days apart. The repeatability and reproducibility of 13C measurements was assessed by Mandel's k and h statistics. RESULTS: Twenty-two centres participated in the study: 18 showed good inter- and intra-laboratory variability, whilst four showed abnormally high inter- or intra-laboratory variability. Breath test results were also significantly affected by the accuracy of the 13C analytical procedures. CONCLUSIONS: A low accuracy of 13C measurements may significantly affect the results of breath tests, leading to inappropriate clinical decisions. Standardization of 13C analysis is required to guarantee optimal 13C measurements and accurate 13C breath test results.  相似文献   
46.
目的建立炎琥宁原料药HPLC含量测定方法。方法采用Lnertsil ODS-3柱(5μm 250×4.6mm),乙腈—磷酸盐缓冲液45:55为流动相,检测波长251nm。结果炎琥宁在50~500μg范围内线性关系良好,相关系数为0.99997。平均回收率为99.39%(RSD为0.4)。结论本法简便、准确、灵敏度高、重现性好,可用于炎琥宁的质量控制。  相似文献   
47.

Background

Overall therapeutic outcomes of advanced non-small-cell lung cancer (NSCLC) are poor. The dendritic cell (DC) immunotherapy has been developed as a new strategy for the treatment of lung cancer. The purpose of this study was to evaluate the feasibility, safety and immunologic responses in use in mature, antigen-pulsed autologous DC vaccine in NSCLC patients.

Methods

Five HLA-A2 patients with inoperable stage III or IV NSCLC were selected to receive two doses of 5 × 107 DC cells administered subcutaneous and intravenously two times at two week intervals. The immunologic response, safety and tolerability to the vaccine were evaluated by the lymphoproliferation assay and clinical and laboratorial evolution, respectively.

Results

The dose of the vaccine has shown to be safe and well tolerated. The lymphoproliferation assay showed an improvement in the specific immune response after the immunization, with a significant response after the second dose (p = 0.005). This response was not long lasting and a tendency to reduction two weeks after the second dose of the vaccine was observed. Two patients had a survival almost twice greater than the expected average and were the only ones that expressed HER-2 and CEA together.

Conclusion

Despite the small sample size, the results on the immune response, safety and tolerability, combined with the results of other studies, are encouraging to the conduction of a large clinical trial with multiples doses in patients with early lung cancer who underwent surgical treatment.

Trial Registration

Current Controlled Trials: ISRCTN45563569  相似文献   
48.
本文初步研究了诺氟沙星缓释片的处方组成。并对不同处方进行了体外溶出试验,实验结果表明:本品的体外释药可维持12h以上且体外溶出符合一级动力学过程。  相似文献   
49.
PURPOSE: To assess survival of patients with metastatic breast cancer treated with high-dose chemotherapy (HDC) versus standard-dose chemotherapy (SDC). PATIENTS AND METHODS: SDC in four Cancer and Leukemia Group B (CALGB) trials was compared with hematopoietic stem-cell support in patients from the Autologous Blood and Marrow Transplant Registry. Cox proportional hazard regression incorporated potentially confounding effects. A total of 1,509 women were enrolled onto CALGB trials, and 1,188 women received HDC. No significant survival differences existed by CALGB trial or HDC regimen. Consideration was restricted to candidates for both SDC and HDC. The resulting sample included 635 SDC and 441 HDC patients. The outcome of interest was overall survival. RESULTS: The HDC group displayed better performance status. The SDC group had slightly better survival in first year after treatment. The HDC group had lower hazard of death from years 1 to 4 and had somewhat higher probability of 5-year survival (adjusted probabilities [95% confidence intervals], 23% [17% to 29%] v 15% [11% to 19%], P =.03). CONCLUSION: After controlling for known prognostic factors in this nonrandomized analysis of two large independent data sets, women receiving HDC versus SDC for metastatic breast cancer have a similar short-term probability of survival, and might have a modestly higher long-term probability of survival.  相似文献   
50.
PURPOSE: To evaluate the results of high-dose chemotherapy and autologous hematopoietic stem-cell transplantation (autotransplants) in patients with diffuse aggressive non-Hodgkin's lymphoma (NHL) who never achieve a complete remission with conventional chemotherapy. PATIENTS AND METHODS: Detailed records from the Autologous Blood and Marrow Transplant Registry (ABMTR) on 184 patients with diffuse aggressive NHL who never achieved a complete remission with conventional chemotherapy and subsequently received an autotransplant were evaluated. Transplants were performed between 1989 and 1995 and were reported to the ABMTR by 48 centers in North and South America. RESULTS: Seventy-nine (44%) of 184 patients achieved a complete remission or a complete remission with residual imaging abnormalities of unknown significance after autotransplantation. Thirty-four (19%) of 184 had a partial remission and 55 (31%) of 184 had no response or progressive disease. Eleven patients (6%) were not assessable for response because of early death. The probabilities of progression-free and overall survival at 5 years after transplantation were 31% (95% confidence interval [CI], 24% to 38%) and 37% (95% CI, 30% to 45%), respectively. In multivariate analysis, chemotherapy resistance, Karnofsky performance status score less than 80 at transplantation, age > or = 55 years at transplantation, receiving three or more prior chemotherapy regimens, and not receiving pre- or posttransplant involved-field irradiation therapy were adverse prognostic factors for overall survival. CONCLUSION: High-dose chemotherapy and autologous hematopoietic stem-cell transplantation should be considered for patients with diffuse aggressive NHL who never achieve a complete remission but who are still chemotherapy-sensitive and are otherwise transplant candidates.  相似文献   
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