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101.
Dongrun Tang Guoxiang Song Shimin Cui Lingen Chen Qingbin LiDepartment of Ophthalmology the Second Affiliated Hospital Tianjin Medical UniversityTianjin ChinaDepartment of Neurosurgery Tianjin Huan Hu Hospital 《眼科学报》1994,(3)
By digital subtraction angiography(DSA), the authors made observations on 108 normal ophthalmic arteries in 80 patients with regard to the origins, courses, branching, morphology and anastomoses of the vessels. The merits and demerits of DSA in observing the ophthalmic artery were discussed. Eye Science 1994; 10: 157- 162. 相似文献
102.
103.
石杉碱甲对基底核大细胞部损毁所致工作记忆障碍的影响 总被引:7,自引:1,他引:6
目的:研究石杉碱甲对基底核大细胞部(NBM)损毁诱导的工作记忆障碍的影响。方法:采用八臂迷宫延迟板程序研究空间记忆。胆碱乙酰转移酶(ChAT)活力测定采用[^3H]乙酰辅酶A转变成[^3H]乙酰胆碱的方法。结果:单侧损毁NBM(卡因酸0.02μmol)导致空间记忆障碍。在不同的延迟间隔,大鼠完成程序产生的正确数减少和错误数增多。损毁侧大脑皮层ChAT酶的含量下降了大约40%。石杉碱甲(0.2mg· 相似文献
104.
有学者认为,所谓改革,就是在持续的摸索和尝试中不断调整步伐、不断自我修正的过程。医疗卫生领域的改革实践同样如此。 相似文献
105.
OBJECTIVE: Many patients with haemorrhoids are investigated because of the fear of missing colorectal cancer (CRC). The aim of this study was to determine whether a primarily clinical approach regarding the need for investigation was safe and did not miss patients with CRC. PATIENTS AND METHODS: Data was collected prospectively on 589 consecutive patients with the principle diagnosis of haemorrhoids at first clinic visit. All had clinical assessment including rigid sigmoidoscopy and were treated by phenol injection or banding. They were categorized for (1) no review unless symptoms persisted -'One Stop SOS' (2) outpatient review or (3) investigation. To check for the development of CRC they were contacted by postal questionnaire or telephone interview with a minimum of one year from diagnosis and treatment. All 589 patients were cross-referenced with the Pathology database and the Hospital Information Services System. RESULTS: Four hundred and sixty-nine (80%) answered the questionnaire; 352 patients (60% of the total group) fell in the 'one stop SOS' outpatient category; 95 (16%) patients were followed up to review response to treatment for large haemorrhoids; 105 (18%) were investigated with barium enema (12%), flexible sigmoidoscopy (4%), colonoscopy (1%) and miscellaneous (1%); 37 (6%) patients were either given a haemorrhoidectomy date or referred on with a different diagnosis. No patients selected for 'one-stop' treatment developed CRC. Five (0.8%) patients were diagnosed with CRC after appropriate investigation was instituted for suspicious symptoms. One patient with distal transverse colon cancer had a delayed diagnosis as she was investigated initially by flexible sigmoidoscopy. CONCLUSION: Most patients with the primary diagnosis of symptomatic haemorrhoids do not need investigation. 相似文献
106.
The acquisition of new food allergy after orthotopic liver transplantation is now a well described phenomenon, mainly reported in children. The etiology of this phenomenon is at present unclear, but has been ascribed by some to tacrolimus treatment. Here we report a case of liver transplant acquired food allergy (LTAFA) in a child who received a split liver graft. The case is remarkable for the absence of new food allergy in the adult recipient of the same graft. This suggests that host-specific factors play an important role in the development of food allergy after liver transplantation, and emphasizes the predisposition that children have toward this phenomenon. Possible mechanisms underlying the development of food allergy after liver transplantation are discussed. In conclusion, tacrolimus treatment alone cannot account for LTAFA. Host factors such as the maturity of immune regulatory mechanisms are likely to play a critical role in the development of new food allergy after a liver transplant. 相似文献
107.
Involvement of Apoptosis in 3-nitropropionic Acid-induced Ischemicl Tolerance to Transient Focal Cerebral Ischemia in Rats 总被引:3,自引:0,他引:3
Preconditioningofbraintissueswithsub lethalstressesorstimulicanresultinresistancetosubse quentlethalischemiceventsinaresponsecalledis chemictolerance .Recently ,severalstudieshaveshownthatasinglesystemicdoseof 2 0mg/kg 3 NPAcausednohistopathologicalabnorm… 相似文献
108.
109.
Ⅰ、Ⅲ型前胶原基因第2外显子核酶对靶RNA的体外切割活性的研究 总被引:5,自引:0,他引:5
目的 体外研究锤头型α1Ⅰ型及Ⅲ型前胶原基因第2外显子片段核酶对各自靶RNA分子的切割活性及反应条件。同时观察两反义核酶对瘢痕中成纤维细胞胶原合成的影响。方法 将含α1Ⅰ型及Ⅲ型前胶原基因第2外显子片段的重组质粒(pT-Ⅰ、pT-Ⅲ),经体外^32P标记转录后形成产物靶RNA。同时将含特异性核酶基因的重组质粒(pT-gⅠ、pT-gⅢ)进行非标记的体外转录,产物(核酶)与各自的^32P-靶RNA按不同的条件混和反应,电泳后放射自显影观察结果。将构建好的核酶以脂质体包裹后导入培养的成纤维细胞内,采用图像分析法观察核酶对成纤维细胞Ⅰ型、Ⅲ型胶原蛋白mRNA合成的影响。结果 两种核酶在37℃、42℃均能有效切割各自的靶RNA,对Mg^2 浓度的要求范围较宽(10~20mmol/L);反应温度从65℃逐渐降至并维持在37℃的条件下核酶切割活性显提高。Ⅰ、Ⅲ型胶原蛋白mRNA的表达明显降低,胶原蛋白生成降低,胶原生成明显受抑制。结论 针对α1Ⅰ型及Ⅲ型前胶原基因第2外显子片段的核酶能有效地在体外对靶RNA进行切割并能有效地抑制瘢痕中成纤维细胞胶原的合成。 相似文献
110.
目的目前国内对QCT骨密度测量的质量控制研究较少,本文介绍了QCT骨密度测量的准确度、精密度试验方法和意义。方法使用东芝CT机自带体模和软件为测量工具,测量四川大学华西骨质疏松研究中心等研制的QCT骨体模(称四川体模)的骨密度值。四川体模固定于15cm深的水浴中模拟人体腰椎,东芝体模置于水浴容器与扫描床面之间,按照人腰椎QCT骨密度测量相同的条件和方法进行操作,每日1次对测量体模连续测量25日,计算SD和CV,分别以25次测量125d25次测量/1d基线作3m的shewhart图。结果测量四川体模从小到大三管骨密度分别的准确度误差为-60.4%、-39.1%和-13.6%,其分别的校正系数为2.69、1.64、1.15,相关系数为0.9966,回归方程Y=35.6+0.958X(X为测量骨密度,Y为校正后骨密度)。本型QCT机骨密度测量的25次/1d及25次,25d精密度误差分别为1.25~5.54%和1.98~7.87%。25次125d的精密度误差要大于25次,d,显示机器一日内精密度误差变化小,随时间延长其变化增大。以25次125d的结果为基线绘制的shewhart图优于25次/d。结论一切QCT骨密度测量都应进行质量控制,准确度必须予以校正,精密度试验应在此基础上进行。这样结果才真实、科学、可靠并具有可比性。 相似文献