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81.
Meta-analysis方法的研究进展 总被引:12,自引:0,他引:12
Meta analysis方法近年国内已逐渐开展应用 ,本文就其基本概念、应用范围、操作步骤及常用的统计学方法作一综述。1 Meta analysis基本概念Meta analysis方法的思想可追溯到 2 0世纪 30年代 ,最初应用于教育学、心理学等社会科学领域是在 6 0年代[1] ,70年代初Ligh和Smith提出了可以由不同研究结果汇总原始数据进行综合分析[2 ] ,1976年由Glass首次命名Meta analysis[3] 。Meta analysis一词的意思是morecomprehensive ,即更加全面的综合或超… 相似文献
82.
威斯康星卡片分类测验用于注意缺陷多动障碍的meta分析 总被引:2,自引:1,他引:2
目的 分析注意缺陷多动障碍 (ADHD)患儿与正常儿童在威斯康星卡片分类测验 (WCST)中各指标成绩的差异。方法 复习国外 14篇有关文献 ,对ADHD患儿和正常儿童WCST的 4个指标 (持续性错误数、分类完成数、非持续性错误数和持续性反应数 )进行meta分析。结果 ADHD和正常对照组在WCST的持续性错误数、完成分类数和非持续性错误数的成绩差异有统计学意义 ,且可靠性较好。两组的持续性反应数也有统计学意义 ,但其可靠性较差。ADHD患儿的平均持续错误数比正常儿童高 0 4 6倍标准差。正常儿童的平均完成分类数比ADHD组高 0 37倍标准差。ADHD患儿的平均非持续性错误数比正常儿童高 0 37倍标准差。ADHD患儿的平均持续性反应数比正常儿童高 0 30倍标准差。 4个指标的效应尺度均在小至中的范围。结论 WCST值得推广应用于ADHD患儿 ,较敏感的指标包括持续性错误数、完成分类数和非持续性错误数。ADHD患儿可能存在前额叶功能缺陷。 相似文献
83.
Ramtin R. Kassir Christopher H. Rassekh John B. Kinsella John Segas Ricardo L. Carrau James A. Hokanson 《The Laryngoscope》1997,107(1):56-61
To assess the role of adjuvant therapy in the treatment of osteogenic sarcoma of the head and neck, treatment and survival information from 173 patients with osteosarcoma of the head and neck was entered into a database. A meta-analysis of the data was attempted with primary emphasis on the effect of adjuvant therapy on disease outcome. The overall 5-year survival was 37%. Patients with mandibular and maxillary tumors had similar survival rates; both groups fared significantly better than patients with extragnathic tumors (P<0.001). Treatment with surgery alone was associated with significantly longer survival rates (P<0.03) than surgery with adjuvant therapy. In the majority of patients reported, information about surgical margins was not available. For this reason, the differences may not adequately represent the effect of adjuvant therapy. While there have been encouraging results with adjuvant treatment protocols for long bone osteosarcoma, the ultimate role of radiation and chemotherapy in the management of osteosarcoma of the head and neck remains unproven. Nevertheless, we recommend that adjuvant therapy be considered due to the poor prognosis in osteosarcoma of the head and neck. 相似文献
84.
生长抑素和生长激素联合治疗胰腺炎与单用生长抑素对照研究的Meta分析 总被引:2,自引:0,他引:2
目的进一步了解生长抑素和生长激素联合治疗与单用生长抑素治疗胰腺炎的疗效差异。方法应用Meta分析方法,对6项研究生长抑素和生长激素联合治疗胰腺炎的病死率、并发症进行同质性检验和合并效应量的估计。结果病死率同质性检验χ2=3.156,P>0.05,并发症同质性检验χ2=1.210,P>0.05,均具有同质性,可以合并进行分析。病死率合并效应量的估计OR合并=3.164,R合并95%可信区间为1.390~7.200,OR合并的检验P<0.05,并发症合并效应量估计OR合并=3.209,R合并95%可信区间为1.747~5.900。结论生长抑素联合治疗组的病死率低于单用生长抑素治疗组。联合治疗组疗效优于生长抑素单用组。 相似文献
85.
极低频电磁场与儿童白血病关系的Meta分析 总被引:1,自引:0,他引:1
目的 探讨极低频电磁场与儿童白血病的关联程度.方法 采用Meta分析的方法,对国内外公开发表的8篇关于极低频电磁场与儿童白血病的流行病学研究文献进行综合定量再分析.根据资料一致性检验采用固定效应模型计算总OR值.结果 极低频电磁场与儿童白血病之间总OR值为1.58,95%可信区间(95%CI)为1.24~2.03,差异有统计学意义(χ^2=13.11,P<0.01).结论 极低频电磁场与儿童白血病具有高度联系,是儿童白血病的危险因素之一. 相似文献
86.
原发性肝癌发病主要危险因素的Meta分析 总被引:16,自引:0,他引:16
目的 :探讨中国人群肝癌发生的主要危险因素 ,为预防决策提供依据。方法 :利用 Meta分析方法综合国内 1987~ 2 0 0 2年关于肝癌发病危险因素的研究文献 15篇。累计病例 4 795例 ,对照 5 90 4例。结果 :各因素合并比值比分别为 :HBV感染 OR=8.90 (95 CI:7.19~ 11.0 0 ) ;乙肝病史 OR=10 .0 2 (95 CI4 .83~ 2 0 .78) ;抗 - HCV OR=4 .4 1(95 CI:2 .72~ 7.14 ) ;肝癌家族史 OR=3.17(95 CI:2 .4 3~ 4 .13) ;饮酒 OR=1.79(95 CI:1.35~ 2 .39) ;饮沟塘水 OR=1.77(95CI:1.30~ 2 .4 2 ) ;吸烟 OR=1.4 1(95 CI:1.0 5~ 1.89)。结论 :目前影响中国人群肝癌发生的主要因素为乙肝病史、HBV感染、遗传因素、丙型肝炎病毒感染等 相似文献
87.
John L. Moran MBBS FRACP Patricia J. Solomon PhD David E. Warn PhD 《Health services & outcomes research methodology》2004,5(3-4):207-226
Methodological aspects of meta-analytic practice, heterogeneity, publication bias, metaregression and effect metric, were investigated in 14 meta-analyses reflecting major therapeutic concern in Critical Care practice. Compared with the standard Q test, the exact Zelen test was more sensitive in identifying heterogeneity. Assessment of heterogeneity impact by the I 2 statistic was consistent with inferences afforded by both the Q and Zelen test. Publication bias was subject to test and metric determination: funnel plots exhibited variable asymmetry across studies and between metrics; the regression asymmetry test appeared more sensitive than the rank correlation test; the “trim and fill” method was the most sensitive, but suggested, on the basis of quantification of the effects of potentially missing studies, that meta-analyses may be resistant to such missingness. Metaregression of treatment effect against control risk using Bayesian hierarchical regression in all metrics (log odds ratio, log risk ratio and RD) suggested that naïve linear regression approaches over-diagnosed significant relationships and exhibited regression dilution. Heterogeneity, publication bias and risk related treatment effects all demonstrate estimator and metric dependence; the RD metric would appear the most capricious in this regard. 相似文献
88.
目的:系统评价我国人群使用的各类降压药治疗原发性高血压痛的降压效果及安全性。方法:运用Meta分析法,对36项国内治疗原发性高血压的临床随机化试验结果进行综合分析。结果:钙拮抗药(CCBs)和ACE抑制药(ACEI)收缩压和舒张压净差值分别为0.36mmHg(P>0.05)和2.24mmHg(P<0.05),疗效率差为7.79%(P<0.05);短效CCBs与ACEIADR发生的RR值1.99(P<0.05)。ACEI和AⅡ拮抗药(AR-Ⅱ)收缩压与舒张压的净差值分别为-0.38和0.4mmHg(P>0.05);疗效率差3.16%(P>0.05);ADR发生的RR值3.55(P<0.05)。国产、合资降压药与进口同类药品的收缩压和舒张压净差值分别为0.30mmHg(P>0.05)和1.74 mmHg(P<0.05);疗效率差为-0.5%(P>0.05);ADR发生的RR值0.89(P>0.05)。高价与低、中价降压药收缩压和舒张压的血压净差异值分别为2.13 mmHg(P<0.05)和0.77 mmHg(P>0.05);疗效率差6.63%(P>0.05);ADR发生的RR值0.64(P>0.05)。结论:CCBs对舒张压降压明显,总疗效高于ACEI,ACEI疗效略高于AR-Ⅱ;同类国产或合资降压药与进口药物相比,对舒张压降压略明显,降压总疗效基本一致;中价降压药总疗效与高价药基本一致;对于轻中度高血压患者,低中价格的降压药同样可以达到一定的临床有效控制率。 相似文献
89.
药物流产与手术流产比较可接受性的Meta分析 总被引:1,自引:0,他引:1
目的 评价米非司酮配伍米索前列醇药物流产与手术流产终止早期妊娠的可接受性,为非意愿妊娠妇女选择流产方法提供参考和为临床医生的临床决策提供证据。方法 检索MEDLINE、EMBASE、Cochranelibrary、CBMdisc、CNKI、VIP等6个医学数据库,手工检索12种相关杂志,并追查参考文献。由2名评价员独立筛选、评价文献和提取数据。对没有异质性的文献进行Meta分析。结果 纳入9篇文献(3565例病例)。流产前妇女认为药物流产痛苦更少(OR=466.51,95%CI:91.37~2381.88);而手术流产更快捷(OR=0.02,95%CI:0.01~0.06)。流产后妇女对两种流产方法满意度相似,差异无统计学意义(P=0.89);药物流产的再选择率更高(OR=2.72,95%a:2.13~3.47);向他人推荐药物流产的比率也更高(OR=4.91,95%CI:2.16~11.16)。结论 药物流产是一种痛苦小的方法,但不如手术流产快捷,其再次选择率和推荐给他人的比率高于手术流产。药物流产与手术流产比较各有利弊,二者的满意度相似,不能相互代替。 相似文献
90.
We conducted a meta-analysis of randomized controlled clinical trials on steroid treatment for multiple sclerosis and optic
neuritis. Of the 25 trials comparing steroids and controls without steroid treatment that we identified 12 were selected for
this review. A meta-analysis was conducted to calculate the overall odds ratio across the studies for the numbers of patients
without functional improvement and with new relapses. The trials included a total of 1714 patients: 998 with multiple sclerosis
and 716 with optic neuritis. Any type of corticosteroids or adrenocorticotropic hormone (ACTH) treatment was considered, as
was any dosage, route of administration, and length of treatment. Main outcome measures were: (a) number of multiple sclerosis
patients who did not improve by at least one point on the EDSS or equivalent scale, or number of optic neuritis patients without
complete recovery of visual acuity at 8 or 30 days and at longer follow-up; (b) number of multiple sclerosis patients with
at least one new relapse, or number of optic neuritis patients in whom definite multiple sclerosis was diagnosed at longer
follow-up. We found that corticosteroids or ACTH produced a significant improvement in disability or visual acuity at 30 days
(odds ratio 0.49; 95 % CI 0.37–0.64). The improvement was not statistically significant at longer follow-up (0.85; 95 % CI
0.67–1.09). The treatment did not significantly reduce the number of patients with relapses (0.74; 95 % CI 0.54–1.01). Both
low and high doses were effective for 30-day improvement, but only high-dose and short-term therapy were factors that identified
subgroups with some reduction in the risk of new relapse. However, the power of the statistical analysis to detect a reliable
difference in the subgroups was low. Steroid treatment is therefore effective in accelerating short-term recovery in patients
with multiple sclerosis or optic neuritis. Whether steroids are also effective in reducing the risk of relapse, and the optimal
dose and length of treatment must still be determined.
Received: 5 August 1999, Received in revised form: 29 December 1999, Accepted: 22 January 2000 相似文献