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ObjectiveThe purpose of this study was to determine whether chiropractic clinicians modulate spinal manipulation (SM) thrust characteristics based on visual perception of simulated human silhouette attributes.MethodsWe performed a cross-sectional within-participant design with 8 experienced chiropractors. During each trial, participants observed a human-shaped life-sized silhouette of a mock patient and delivered an SM thrust on a low-fidelity thoracic spine model based on their visual perception. Silhouettes varied on the following 3 factors: apparent sex (male or female silhouette), height (short, average, tall), and body mass index (BMI) (underweight, healthy, obese). Each combination was presented 6 times for a total of 108 trials in random order. Outcome measures included peak thrust force, thrust duration, peak preload force, peak acceleration, time to peak acceleration, and rate of force application. A 3-way repeated measures analysis of variance model was used to for each variable, followed by Tukey's honestly significant difference on significant interactions.ResultsPeak thrust force was reduced when apparent sex of the presented silhouette was female (F1,7 = 5.70, P = .048). Thrust duration was largely invariant, except that a BMI by height interaction revealed a longer duration occurred for healthy tall participants than healthy short participants (F4,28 = 4.34, P = .007). Compared to an image depicting obese BMI, an image appearing underweight lead to reduced peak acceleration (F2,5 = 6.756, P = .009). Clinician time to peak acceleration was reduced in short compared to tall silhouettes (t7 = 2.20, P = .032).ConclusionVisual perception of simulated human silhouette attributes, including apparent sex, height, and BMI, influenced SM dose characteristics through both kinetic and kinematic measures. The results suggest that visual information from mock patients affects the decision-making of chiropractic clinicians delivering SM thrusts.  相似文献   
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《Radiography》2022,28(2):454-459
IntroductionMR facilities must implement and maintain adequate screening and safety procedures to ensure safety during MR examinations. The aim of this study was to evaluate a multi-step MR safety screening process used at a 7T facility regarding incidence of different types of safety risks detected during the safety procedure.MethodsSubjects scheduled for an MR examination and having entered the 7T facility during 2016–2019 underwent a pre-defined multi-step MR safety screening process. Screening documentation of 1819 included subjects was reviewed, and risks identified during the different screening steps were compiled. These data were also related to documented decisions made by a 7T MR safety committee and reported MR safety incidents.ResultsPassive or active implants (n = 315) were identified in a screening form and/or an additional documented interview in 305 subjects. Additional information not previously self-reported by the subject, regarding implants necessitating safety decisions performed by the staff was revealed in the documented interview in 102 subjects (106 items). In total, the 7T MR safety committee documented a decision in 36 (2%) of the included subjects. All of these subjects were finally cleared for scanning.ConclusionA multi-step screening process allows a thorough MR screening of subjects, avoiding safety incidents. Different steps in the process allow awareness to rise and items to be detected that were missed in earlier steps.Implications for practiceSafety questions posed at a single timepoint during an MR screening process might not reveal all safety risks. Repetition and rephrasing of screening questions leads to increased detection of safety risks. This could be effectively mitigated by a multi-step screening process. A multi-disciplinary safety committee is efficient at short notice responding to unexpected safety issues.  相似文献   
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CRF55_01B是我国报道的HIV-1主要流行毒株之一,具有较为独特的流行病学和基因进化特征。近几年HIV-1分子流行病学监测发现CRF55_01B已经成为我国第五个主要流行HIV-1毒株。本研究从他的发现起源、流行情况、致病性和耐药性及参与的重组等方面进行综述,并讨论了与其流行密切相关的社会和生物学因素。  相似文献   
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Following adoption of moderately hypofractionated radiotherapy as a standard for localised prostate cancer, ultrahypofractioned radiotherapy delivered in five to seven fractions is rapidly being embraced by clinical practice and international guidelines. However, the question remains: how low can we go? Can radiotherapy for prostate cancer be delivered in fewer than five fractions? The current review summarises the evidence that radiotherapy for localised prostate cancer can be safely and effectively delivered in fewer than five fractions using high dose rate brachytherapy or stereotactic body radiotherapy. We also discuss important lessons learned from the single-fraction high dose rate brachytherapy experience.  相似文献   
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目的:分析《伤寒杂病论》中厚朴的量效关系及配伍用药规律,以更好地指导临床。方法:总结归纳《伤寒杂病论》中含有厚朴的条文,采用SPSS 23.0统计软件分析厚朴剂量与相关因素之间的关系。结果:符合筛选条件含厚朴方剂共11首,占全书总方剂数的9.73%。二元相关性分析显示,厚朴单次用量与药味数、用水量、与剩余水量、单次服用水量和服用次数无明显相关性(P>0.05)。单因素逻辑回归分析显示,厚朴是否为主药与厚朴单次用量、用水量有相关性(P<0.05)结论:厚朴以配伍用药为主,未单独使用,多应用在阳明经证,从量效关系发现,厚朴是否为主药与厚朴单次用量、用水量有相关性。厚朴对于虚实类疾病通过配伍均可达到治疗效果,从药物作用气机的升降浮沉角度,厚朴在体内作用以降为主。厚朴小剂量使用,配伍麻黄、杏仁、生姜、桂枝等可治疗呼吸系统疾病,大剂量配伍半夏、人参、生姜、枳实等可治疗消化系统疾病。  相似文献   
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尚海方 《中国校医》2022,36(5):369-372
目的 对比分析两种剂型克霉唑在轻中度外阴阴道假丝酵母菌病(VVC)治疗中的临床价值。方法 以随机数字表法,将2019年5月—2020年8月收治的98例轻中度VVC患者予以分组,观察组49例,给予克霉唑乳膏治疗,对照组49例,给予克霉唑阴道片治疗,对两组治疗效果、症状缓解时间、不良反应发生情况及患者依从性予以观察。结果 观察组治疗总有效率为97.96%与对照组93.88%比较差异无统计学意义(χ2=0.2606,P=0.581);观察组外阴肿胀缓解时间比对照组短(2.63±0.51vs2.97±0.65 d,t=2.881,P=0.005),差异有统计学意义;观察组外阴瘙痒缓解时间比对照组短(2.35±0.47vs2.71±0.59 d,t=3.341,P=0.001);观察组阴道分泌物异常缓解时间比对照组短(2.92±0.63vs3.28±0.67 d,t=2.740,P=0.007);观察组不良反应发生率为8.16%,与对照组4.08%比较差异无统计学意义(χ2=0.178,P=0.625),;观察组用药依从率为100.00%稍高于对照组91.84%(χ2=2.346,P=0.168)。结论 在轻中度VVC治疗中,克霉唑阴道片与克霉唑乳膏均为安全、有效剂型,但克霉唑阴道乳膏起效相对较快,患者用药依从性相对较好,更具推广价值。  相似文献   
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IntroductionSelective internal radiation therapy (SIRT) is a potential treatment of primary renal cell carcinoma (RCC) deemed unsuitable for conventional therapy. RESIRT is the first-in-human study to evaluate safety and feasibility of SIRT for primary RCC.Patients and MethodsPatients with RCC, unsuitable for, or who declined conventional therapy, were eligible. A single transfemoral micro-catheter administration of yttrium-90 (Y-90) resin microspheres (SIR-Spheres) was delivered super selectively via the renal artery to the tumour at intended radiation doses of 75, 100, 150, 200, 300 Gy and a final cohort with a procedural endpoint of “imminent stasis,” in a dose-escalation design. Post-SIRT follow-up was 12 months. Study endpoints included safety and toxicity 30-days and 12-months post-SIRT and tumour response (RECIST v1.1).ResultsIn total, 21 patients were enrolled, mean (SD) age was 75 (9.3) years, WHO performance status was 0 in 81%, 12 (57%) had stage 3 chronic kidney disease, and 7 (33%) had prior contralateral nephrectomy. Overall, 71% of patients completed 12 months of follow-up. Intended doses were delivered without any dose-limiting toxicity. Seventeen out of 21 (81%) patients experienced an adverse event (AE) from any cause within 30 days post-SIRT; all SIRT-related AEs were grade 1 to 2. Best overall tumour responses were partial response 1/21 (4.8%), stable disease 19/21 (90.5%) and progressive disease 1/21 (4.8%).ConclusionThis study demonstrated good tolerability of SIRT at all dose levels including “imminent stasis” in treating primary tumours in RCC patients otherwise unsuitable for conventional therapy. SIRT with Y-90 resin microspheres may be a feasible treatment option for RCC.  相似文献   
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BackgroundIn the phase III MDS-005 study of patients with lower-risk, non-del(5q) myelodysplastic syndromes, lenalidomide was associated with a higher rate of ≥ 8 weeks red blood cell transfusion independence (RBC-TI) compared with placebo, but also with a higher risk of hematologic adverse events (AEs).Patients and MethodsThis analysis evaluated the ratio of clinical benefit-risk in patients treated with lenalidomide or placebo, and assessed the effect of lenalidomide dose reductions on response. Clinical benefit was a composite endpoint defined as RBC-TI, transfusion reduction ≥ 4 units packed red blood cells, hemoglobin increase ≥ 1.5 g/dL, or cytogenetic response.ResultsThe rate of clinical benefit was higher with lenalidomide than with placebo (31.9% vs. 3.8%). The ratio of response (RBC-TI and clinical benefit) to risk (hematologic AEs) favored lenalidomide over placebo. Patients who underwent ≥ 1 lenalidomide dose reduction had a longer duration of treatment, received a higher cumulative dose, and were more likely to experience clinical benefit versus patients without dose reductions.ConclusionDespite the occurrence of hematologic AEs, the overall benefit-risk profile supported lenalidomide treatment. Appropriate management of hematologic AEs by dose reductions may help patients with myelodysplastic syndromes to remain on treatment and achieve clinical benefit.  相似文献   
10.
放射性肺损伤是胸部肿瘤放疗后常见并发症,随着对放射性肺炎研究不断深入,如何为基础研究和药物干预寻求最佳的动物模型和效应评价已成为当前亟待解决的难题之一。通过检索近10年文献,对不同放射性肺损伤模型动物及放射部位的选择、照射剂量的确定、照射方法的比较和动物模型效应评价进行了对比研究,以期寻找建立放射性肺损伤动物模型的稳定方法和较为明确的效应机制,为防护和减缓放射性肺损伤的发生发展而进行的基础研究和药物研制提供可靠的方法。  相似文献   
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