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71.
眼轴线后部眶容积增大与眼球内陷比值的测定研究 总被引:1,自引:0,他引:1
目的:通过测量眼眶爆裂性骨折伴有眼眶扩大患者的后部眼眶容积、观察眼球内陷出现的时间及程度,研究后部眶容积扩大与眼球内陷的关系比值,为病情预测和眶内填充手术提供比较精确的参考数据。方法:将96例患者按发病时间分为早期病例组(60例、受伤时间1周以内)和晚期病例组(36例、受伤时间3个月以上),早期组除进行后部眼眶容积测量外,分别于1周、2周、3周测定眼球突出度(相差>1mm为阳性),记录眼球内陷出现时间,用卡方检验进行统计学分析;晚期组测量后部眶容积增大值和眼球内陷量,对其相关性采用Pearson统计方法进行统计学分析,并得出回归方程及相关系数。结果:早期组60例患者中,(58.33%)例患者在1周内出现眼球内陷,4(880%)例在2周内出现内陷,3周时有5(388.33%)例呈现出内陷;2周时出现眼球内陷的例数与1周时有显著性差异(χ2=62.484,P<0.001),2周时出现眼球内陷例数与3周时无差异(χ2=1.563,P>0.05),1周时出现眼球内陷例数与3周时有显著差异(χ2=76.885,P<0.001),后部眶容积增大与眼球内陷的比值约为1.0,两者之间呈正相关(r=0.994,P<0.001),即后部眶容积每增加1ml,产生1.0mm的眼球内陷。结论:眼球内陷通常于伤后2周~3周出现,3个月时趋向稳定;后部眶容积增大与眼球内陷产生比值为1.0,呈正相关;后部眶容积扩大与眼球内陷比值可预测发生眼球内陷的可能性和程度,为手术矫正眼球内陷提供可靠、精确的参考,具有十分重要的临床指导意义。 相似文献
72.
放射性脑损伤是放射治疗的严重的并发症,其与脑肿瘤复发的鉴别诊断非常困难,目前主要依靠影像学诊断,核磁共振弥散加权像、磁共振波谱、正电子发射型计算机体层显像、单光子发射计算机体层显像等被认为对于鉴别诊断有一定的帮助,但其敏感性和特异性还有待于进一步研究。最终确诊依赖标本的组织学检查。 相似文献
73.
Severe hemorrhagic radiation proctitis advancing to gradual cessation with hyperbaric oxygen 总被引:3,自引:0,他引:3
Dr. Jacky Charneau MD Gilles Bouachour MD Bruno Person MD Pascal Burtin MD Jean Ronceray MD Jean Boyer MD 《Digestive diseases and sciences》1991,36(3):373-375
Summary We report a case of a male patient suffering from a severe hemorrhagic radiation proctitis which gradually ceased with hyperbaric oxygen. We discuss the mechanisms of chronic radiation injury and the effect of the hyperbaric oxygen. This therapy is proposed as an alternative to surgical intervention for this abnormality. 相似文献
74.
目的:探讨改进的微波辐射器探头治疗宫颈糜烂的疗效。方法:将微波辐射器探头由双直线形、双针形、单针形等点线状改进成为“单舌形”和“双舌形”两种弧形平面探头,用于治疗宫颈糜烂。分析1999-2002年450例宫颈糜烂治疗资料,其中300例经微波治疗(A组),150例经C02—激光治疗(B组),随访1—3个月。结果:两组治疗后3个月内A组治愈率明显高于B组(P<0.005),总有效率A组明显高于B组(P<0.025)。两组术中、术后不良反应比较:术中宫颈创面出血A组明显低于B组(P<0.005),术中腹痛、脱痂期出血量、术后局部感染率方面两组相似。结论:所改进的微波辐射器探头治疗宫颈糜烂治愈率高,操作安全,术后并发症少,医患乐于接受。 相似文献
75.
目的 研究经肝动脉化疗栓塞 (THACE)治疗肝癌过程中 ,患者受到的X射线辐射 ,为THACE放射防护提供依据。方法 回顾性分析 82例HCC患者的辐射剂量资料 ,DSA机 (Angiostar Plus)配置穿透电离室型剂量监测系统 (DiamentorK1andDiamentorED) ,在线读取面积剂量乘积DAP(cGy cm2 )和入射表面剂量ESD(mGy) ,采用Monte Carlo转换因子估算有效剂量ED(mSv)。并分析近期 10例THACE患者 ,在提高基值管电压、减低透视脉冲频率和摄影帧数下对辐射剂量的影响。结果 82例HCC患者透视时间 (35 3± 2 1 1)min ,摄影 (2 34± 10 8)帧 ,DAP为 (2 174 8± 12 4 2 4 )cGy cm2 ,ESD为 (96 4± 6 32 )mGy ,ED为 (34 8± 19 9)mSv。透视对总DAP的贡献 (2 4 0± 12 7) %小于摄影 (75 9± 12 7) % ,透视对ESD值的贡献 (4 9 8± 14 9) % ,与摄影相似 (5 1 6± 14 2 ) %。近期的 10例THACE患者的每分钟透视剂量、每帧摄影剂量及总剂量都比HCC患者明显降低。结论 在THACE过程中患者受到一次性较大剂量X射线照射。适度提高基值管电压、减低透视脉冲频率和缩减摄影帧数 ,可以有效降低患者的辐射剂量 相似文献
76.
乳房体积生物立体测量系统的研制 总被引:7,自引:1,他引:6
目的 利用立体视觉方法建立乳房体积测量系统 ,并探讨其准确性和精确程度。方法 通过采用两台CCD摄相机从两个不同视角观察乳房模型 ,运用激光投射仪和光栅获得计算机能识别的平行采样点 ,依靠计算机图像处理技术和生物立体测量技术 ,求取乳房模型表面采样点的三维坐标 ,设计乳房体积测量运算模式 ,在Windows下编制程序 ,建立乳房体积测量和分析系统 ,应用所建的测量系统和水体积置换术分别对 12例乳房模型进行体积测量 ,并将两种测量方法及其结果进行比较和统计分析 ,观察其精确性和准确性。结果 本系统测量乳房体积实现了数据的快速处理 ,测试空间范围为12 0mm× 14 0mm× 80mm ,特点是快速、非接触性和非侵入性。与水体积置换方法比较 ,P =0 .4 73>0 .0 5 ,差值的 95 %可信区间为 - 14 .0 2~ 7.0 8ml。结论 本系统可应用于乳房体积测量 ,简捷而且精确 ,为临床工作提供了一种有效手段 ,并为软组织形态分析的开展提供了一种新的理论基础。 相似文献
77.
A new decontaminated hassles measure for adults, the Survey of Recent Life Experiences, was developed and validated. An initial pool of 92 items was administered to 100 subjects along with the Perceived Stress Scale. Fifty-one items were selected, based on significant correlations with the latter scale. The alpha reliability of the resultant final form of the Survey of Recent Life Experiences and its correlation with perceived stress were both high. In a separate cross-replication sample of 136 adults, the alpha reliability of the Survey and its correlation against the Perceived Stress Scale remained acceptably high. Moreover, separate-sex analyses supported the reliability and validity of the Survey of Recent Life Experiences across gender. Factor analysis of the Survey yielded six interpretable factors. Intercorrelations among subscales based on these factors were generally modest, suggesting that the scale is relatively free from contamination by psychological distress.The work reported was facilitated by a grant from the Social Sciences and Humanities Research Council of Canada's Small Grant Program, administered by the Office of Research Administration, York University. The authors appreciate the cooperation of staff at the Ontario Science Centre, Toronto, and the assistance of Maria Gurevich in verifying the data. 相似文献
78.
Anthony P Cullen Olanrewaju M Oriowo Anita C Voisin 《Clinical & experimental optometry》1997,80(3):80-86
Concern about short- and long-term ultraviolet radiation (particularly UVB) damage to the eye has led to increased research in this area. Numerous studies have confirmed the pathogenic enhancing roles of reflected ultraviolet (UV) and visible radiation in our environment. There is concern that conventional sunglasses do not protect the eye adequately from reflected rays (albedo), especially on the lateral aspect, from behind and from below. Using eye models and computer ray tracing methods, the pathways of oblique rays incident at the temporal peripheral cornea have been plotted by Maloof, Ho and Coroneo.1 These rays are refracted and focused and theoretically can result in up to 20 times the concentration of incident irradiance at the nasal anterior chamber angle and nasal equatorial cortex of the crystalline lens. The purpose of this study was to determine the limits of angular subtense of the incident peripheral light which is refracted in this manner in human subjects and to investigate the relation between corneal shape and certain ocular parameters to the limits. A statistically significant positive correlation was found between temporal entrance angle and anterior chamber depth (r = 0.70, P< 0.0006). The entrance angle ranged from 15 degrees to 30 degrees and was located 10 degrees to 45 degrees posterior to the coronal plane. Our results support Maloof and colleagues' predictions for the implication of focused peripheral UV and high intensity visible radiation in the pathogenesis of pterygium and cortical cataract and emphasise the need for lateral eye protection in conditions of high ultraviolet albedo. 相似文献
79.
Moshe Stein N. Haim Abraham Kuten Yafa Doron Yehudi T. Ben Arieh Yoram Cohen 《Journal of surgical oncology》1992,51(4):270-273
Thirty-three patients with primary gastrointestinal lymphoma (GIL) followed at Ankara University Medical School have been evaluated. The most frequent locations of the disease are the small intestine (48.4%) and the stomach (39.3%). The intermediate and high grade lymphomas constitute 84.8% of the cases. The mean age of the patients with small intestinal lymphoma is 28.7 years and 47.1 years for those with gastric lymphoma. The patients treated with surgery and chemotherapy (S+CT) have a longer survival than those treated with chemotherapy (CT) alone. In conclusion: 1) Small intestinal lymphoma occurs more frequently than gastric lymphoma in our study. 2) The median age of the Turkish patients with primary GIL is approximately 10 years less than those in the Western countries. 3) The therapeutic results of S+CT are superior to those of CT in the early stages of the disease. 相似文献
80.
The effect associated with the substitution of adenine (A) for guanidine (G) in the promoter region of the apolipoprotein AI gene (?75 bp) with plasma apo AI and high-density lipoprotein (HDL) levels was investigated in the European Atherosclerosis Research Study (EARS). This is a study of healthy offspring (cases) of fathers who had suffered premature myocardial infarction (MI) before age 55 years (n = 565) and age- and sex-matched controls (n = 1,078) from 12 European countries, divided into 5 regions based on geography and language. The frequency of the polymorphism was not significantly different among the regions and the relative frequency of the rare A allele was similar in cases and controls (0.159 vs. 0.142) combining data from all regions. Individuals with one or more A allele had significantly higher plasma apo AI levels (P < 0.05) than individuals homozygous for the G allele. This effect was consistent in all regions. The data were analyzed separately in males and females. In females, those with one or more A allele had significantly higher apo AI levels (P = 0.05) than individuals homozygous for the G allele, and this raising effect of the A allele was greater in cases than controls for both apo AI (5.23% vs. 1.56%) and HDL (4.48% vs. 1.89%). In males, the A allele was associated with higher levels of apo AI and HDL, but the effect was much smaller and the differences did not reach statistical significance. In the females, where the effect of the A allele was strongest, the effect on apo AI associated with genotype was evident in non-smokers, and individuals with one or two A alleles had 3.6% higher apo AI and 3.14% higher HDL levels than individuals homozygous for the G allele. However, in the female smokers the raising effect of the A allele was greatly reduced (0.56%). Thus genetic variation in the promoter region of the apo AI gene is associated with differences in apo AI and HDL levels in healthy individuals throughout Europe, but the effect is modulated by gender, environmental factors such as smoking, and a family history of MI. 相似文献