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91.
①目的 调查长途汽车司机有关艾滋病( A I D S)的知识及对 A I D S的态度,为进一步在该人群中开展艾滋病知识的宣传教育、制订有关预防措施提供依据。②方法 对青岛市 3 个长途汽车运输公司以单纯随机抽样方法抽取74 名进行调查,调查表采用匿名自填方式。③结果 大多数调查对象对艾滋病的病原体、传播途径、临床表现及潜伏期病人的危险性认识不足,而对艾滋病的有关知识感兴趣,并希望通过各种途径加以了解。④结论 长途汽车司机对有关艾滋病的知识了解较少,应加强对该人群有关艾滋病知识的宣传教育。 相似文献
92.
Grech V 《European journal of epidemiology》1999,15(10):881-887
Differing pathological haemodynamics in cardiac malformations lead to varying modes and timings of presentation. This study identifies historical trends in presentation of congenital heart disease in a population-based study. All patients diagnosed as having congenital heart disease in Malta between 1960–1994 were included (n = 868). Analysis was carried out on trends in referral sources, modes of presentation and birth prevalence. The number of patients diagnosed with congenital heart disease increased over the period under study. For both patients not requiring intervention (n = 283) and those requiring intervention (n=585), the proportion diagnosed prior to hospital discharge increased (p 0.005). There was a decreasing trend for general practitioners to refer cases (p < 0.0001), and an increasing trend for paediatricians to refer such patients (p 0.0003). The commonest presentation to the general practitioner was an incidental finding (92%), while paediatricians referred more patients for cyanosis or heart failure (p 0.005). For lesions not requiring intervention, the commonest lesion referred was ventricular septal defect from all sources. For lesions requiring intervention, the commonest lesion detected prior to hospital discharge was tetralogy of Fallot. Atrial septal defects were the commonest lesions detected after discharge by both paediatricians and general practitioners. An increase in the proportion of hospital diagnoses is attributed to increasing rate of hospital delivery, and greater training and experience in doctors performing neonatal examinations prior to discharge. Patients diagnosed after discharge are increasingly diagnosed by paediatricians due to an increasing pool of paediatricians and better parent awareness and education. 相似文献
93.
94.
Kenya Murase Shuji Tanada Takeshi Inoue Yoshifumi Sugawara Ken Hamamoto 《European journal of nuclear medicine and molecular imaging》1993,20(1):32-38
Attenuation coefficient maps (-maps) are a useful way to compensate for non-uniform attenuation when performing single photon emission tomography (SPET). A new method was developed to record single photon transmission data and a-map for the brain was produced using a four-head SPET scanner. Transmission data were acquired by a gamma camera opposite to a flood radioactive source attached to one of four gamma cameras in the four-head SPET scanner. Attenuation correction was performed using the iterative expectation maximization algorithm and the-map. Phantom studies demonstrated that this method could reconstruct the distribution of radioactivity more accurately than conventional methods, even for a severely non-uniform-map, and could improve the quality of SPET images. Clinical application to technetium-99m hexamethylpropylene amine oxime (HMPAO) brain SPET also demonstrated the usefulness of this method. Thus, this method appears to be promising for improvement in the image quality and quantitative accuracy of brain SPET.This work was presented in part at the World Congress on Medical Physics and Biomedical Engineering, 7–12 July 1991, Kyoto, Japan 相似文献
95.
96.
外周原始神经外胚层肿瘤形态学免疫表型及临床预后研究 总被引:10,自引:2,他引:10
目的:探讨外周原始神经外胚层肿瘤(PNET)的临床表现,病理及免疫组织化学特点及预后。方法:对15例外周原始神经外胚层肿瘤进行临床资料及预后,病理组织形态学和超微结构特点及免疫组化表型研究。结果:患者以男性为主,男女之比约为6.5:1,年龄6~35岁,年龄中位数为16,发生部位较多,可发生在直肠,腹膜后,腹股沟,淋巴结,胸壁,睾丸,鼻腔及骨组织等;免疫组化:肿瘤均弥漫表达CD99,并不同程度地表达NSE,SYN,CgA等,但不表达CK,Desmin,LCA等,其中1例表达组织化学染色PAS,随访最长时间为24月。结论:PNET是一种发生在年轻男性,进展迅速,预后非常差的恶性小圆细胞肿瘤,认识其临床病理特点及免疫组化表型对于该恶性肿瘤的诊断及临床治疗意义重大。 相似文献
97.
Clinical trials for binary therapies, like boron neutron capture therapy (BNCT), pose a number of unique problems and challenges in design, performance, and interpretation of results. In neutron beam development, different groups use different optimization parameters, resulting in beams being considerably different from each other. The design, development, testing, execution of patient pharmacokinetics and the evaluation of results from these studies differ widely. Finally, the clinical trials involving patient treatments vary in many aspects such as their dose escalation strategies, treatment planning methodologies, and the reporting of data. The implications of these differences in the data accrued from these trials are discussed. The BNCT community needs to standardize each aspect of the design, implementation, and reporting of clinical trials so that the data can be used meaningfully. 相似文献
98.
Chittukadu K. Gajalakshmi Viswanathan Shanta Ranganathan Rama 《Cancer causes & control : CCC》1998,9(2):131-136
Objectives: This study was carried out to evolve a method to improve the registration of cancer mortality data in Chennai (Madras, India). Methods: Data on cancer deaths have been collected from the Vital Statistics Department (VSD) by a population-based cancer registry (PBCR) in Chennai only since 1982. The low mortality-to-incidence ratio during 1982-84 suggested under-registration of mortality data. Since 1985, the PBCR has taken special effort to ascertain the vital status of cancer cases by sending reply-paid postcards and/or making house visits. The data on all deaths occurring in Chennai, irrespective of stated cause of death in the death certificate, have been collected from the VSD since 1992. Results: Deaths that occurred in Chennai and obtained by sending reply-paid postcards and/or making house visits were registered in VSD as non-cancer causes of death; hence, these data were not collected from VSD. The sensitivity and positive predictive values of death certificates on cancer diagnosis based on 1992 and 1993 mortality data were 57 percent and 99.5 percent, respectively. Conclusion: Since the accuracy of death certificate information on cancer diagnosis is relatively low in a developing country such as in India, collecting data on all deaths will improve the mortality data registration in PBCRs. 相似文献
99.
Sadeghi H Allard P Shafie K Mathieu PA Sadeghi S Prince F Ramsay J 《Gait & posture》2000,12(3):257-264
Timing in peak gait values shifts slightly between gait trials. When averaged, the standard deviation (S.D.) in gait data may increase due to this inter-trial variability unless normalization is carried out beforehand. The objective of this study was to determine how curve registration, an alignment technique, can reduce inter-subject variability in gait data without perturbing the curve characteristics. Twenty young, healthy men participated in this study each providing a single gait trial. Gait was assessed by means of a four-camera high-speed video system synchronized to a force plate. A rigid body three-segment model was used in an inverse dynamic approach to calculate three-dimensional muscle powers at the hip, knee and ankle. Curve registration was applied to each of the 20 gait trials to align the peak powers. The mean registered peak powers increased by an average of 0.10±0.13 W/kg with the highest increases in the sagittal plane at push-off. After performing curve registration, the RMS values decreased by 13.6% and the greatest reduction occurred at the hip and knee, both in the sagittal plane. No important discontinuities were reported in the first and second derivatives of the unregistered and registered curves. Curve registration did not have much effect on the harmonic content. This would be an appropriate technique for application prior to any statistical analysis using able-bodied gait patterns. 相似文献
100.
评价一个正在进行尚未完成的临床试验 ,研究者常常采用期中分析方法。由于新药开始用于临床治疗时 ,其安全性和有效性方面存在很多不确定的因素 ,采用期中分析方法设计能有效解决这些问题。本文阐述了如何计划和实施期中分析的方法和作用 ,对期中分析有关组织的职责也进行了讨论。 相似文献