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51.
A procedure is described for standardising the determination of adenosine 5-triphosphate and phosphocreatine concentration ([ATP] and [PC], respectively, in absolute arbitrary units) in human muscle by nuclear magnetic resonance (NMR) spectroscopy. The individual 31phosphorus (21P)-NMR spectra obtained on equal hemispherical tissue volumes (muscle plus skin and fat) were corrected for the thickness of the skin and of the subcutaneous fat. The volumes investigated were standardised using an external reference. The procedure described made possible the comparison of high energy phosphate concentrations among different subjects. It was applied to the assessment of [ATP] and [PC] in four groups of sedentary subjects (children, and adults aged 20–35, 35–50 and over 50 years), and in a group of athletes (volleyball players). The [ATP] and [PC] were not statistically different in the groups investigated.  相似文献   
52.
AIMS: Human chorionic gonadotrophin (hCG) is a useful marker for chorionic proliferative disorders, such as choriocarcinoma. Although hCG synthesis in lung cancers is frequent, primary pulmonary choriocarcinoma (PCC) is rare. To clarify the differences between primary choriocarcinoma and hCG-producing giant cell carcinoma (GCC) of the lung, we compared the clinicopathological and immunohistochemical findings of these tumours. METHODS AND RESULTS: Three patients, one with PCC and two with hCG-producing GCC, were included in this study. They were all middle-aged men and habitual smokers. The growth of these tumours and the progression of the clinical courses were extremely rapid, and the patients all died within 8 months after the pulmonary tumours were found. Haemorrhagic appearance was a common macroscopic feature of the specimens obtained. Microscopically, both types of tumours mainly consisted of atypical polygonal cells. While PCC contained many syncytial trophoblast-like multinucleated cells that had strong immunoreactivity for anti-hCG, such cells were relatively few in hCG-producing GCC. These histological and immunohistochemical findings reflected the serum test result for hCG, which was higher in the case of PCC. CONCLUSIONS: There are a few differences between PCC and hCG-producing GCC, as described above. Reliable distinction between them seems to be difficult for pathologists and worthless for clinicians.  相似文献   
53.
To investigate the representation of motor sequence, we tested transfer effects in a motor sequence learning paradigm. We hypothesize that there are two sequence representations, effector independent and dependent. Further, we postulate that the effector independent representation is in visual/spatial coordinates, that the effector dependent representation is in motor coordinates, and that their time courses of acquisition during learning are different. Twelve subjects were tested in a modified 2x10 task. Subjects learned to press two keys (called a set) successively on a keypad in response to two lighted squares on a 3x3 display. The complete sequence to be learned was composed of ten such sets, called a hyperset. Training was given in the normal condition and sequence recall was assessed in the early, intermediate, and late stages in three conditions, normal, visual, and motor. In the visual condition, finger-keypad mapping was rotated 90 degrees while the keypad-display mapping was kept identical to normal. In the motor condition, the keypad-display mapping was also rotated 90 degrees, resulting in an identical finger-display mapping as in normal. Subjects formed two groups with each group using a different normal condition. One group learned the sequence in a standard keypad-hand setting and subsequently recalled the sequence using a rotated keypad-hand setting in the test conditions. The second group learned the sequence with a rotated keypad-hand setting and subsequently recalled the sequence with a standard keypad-hand setting in the test conditions. Response time (RT) and sequencing errors during recall were recorded. Although subjects committed more sequencing errors in both testing conditions, visual and motor, as compared to the normal condition, the errors were below chance level. Sequencing errors did not differ significantly between visual and motor conditions. Further, the sequence recall accuracy was over 70% even by the early stage when the subjects performed the sequence for the first time with the altered conditions, visual and motor. There were parallel improvements thereafter in all the conditions. These results of positive transfer of sequence knowledge across conditions that use dissimilar finger movements point to an effector independent sequence representation, possibly in visual/spatial coordinates. Initially the RTs were similar in the visual and the motor conditions, but with training RTs in the motor condition became significantly shorter than in the visual condition, as revealed by significant interaction for the testing stage and condition term in the repeated measures ANOVA. Moreover, using RTs for single key pressing in the three conditions as baseline indices, it was again observed that RTs in the visual and motor conditions were not significantly different in the early stage, but motor RTs became significantly shorter by the late testing stage. These results support the hypothesis that the motor condition benefits more than the visual because it uses identical effector movements to the normal condition. Further, these results argue for the existence of effector dependent sequence representation, in motor coordinates, which is acquired relatively slowly. The difference in the time course of learning of these two representations may account for the differential involvement of brain areas in early and late learning phases found in lesion and imaging studies.  相似文献   
54.
Summary 5-day-old neonatal offspring of exercised or non-exercised pregnant Sprague Dawley rats were used to prepare primary cultures of beating myocardial cells. The cells from the exercise group exhibited a slower beating rate for both single and aggregate cells; a larger cell size; an increased percentage of contracting cells; a greater capacity to form confluent monolayers, and a greater viability. It was concluded that exercise during the period of pregnancy produced morphological alterations in the myocardium of the progeny.  相似文献   
55.
Medaka fish (Oryzias latipes) were exposed to various doses of X-rays or fast neutrons, and the frequency of micronucleated cells (MNCs) was measured in gills sampled at 12- or 24-hr intervals from 12 to 96 hr after exposure. The resulting time course of MNC frequency was biphasic, with a clear peak 24 hr after exposure, irrespective of the kind of radiation applied and the dose used. The half-life of MNCs induced in the gill tissues by the two exposures fluctuated around 28 hr, with no significant dose-dependent trend for either X-ray- or neutron-exposed fish. As assayed 24 hr after exposure, the MNC frequency increased linearly over the control level with increasing doses of both X-rays and fast neutrons. The relative biological effectiveness (RBE) of fast neutrons to X-rays for MNC induction was estimated to be 4.3 +/- 0.6. This value is close to the RBE value of 5.1 +/- 0.3 reported for fast neutron induction of somatic crossing-over mutations in Drosophila melanogaster that arise from recombination repair of DNA double-strand breaks. These results and other data support our conclusion that the medaka gill cell micronucleus assay is a reliable short-term test for detecting potential inducers of DNA double-strand breaks.  相似文献   
56.
目的 学生朋友心理辅导员是高校学生心理健康教育网络系统的重要组成部分。如何在较短的时间里,经过比较系统的培训,让普通的大学生成长为合格的学生朋友心理辅导员并承担起为同学进行心理护理的义务,是构建高校学生心理健康教育网络系统的关健。方法 明确培训目标和担任工作职能,培训内容科学,知识构成合理,培训方法灵活,进行培训前测与后测和培训效果评估,注重实践锻炼和心理督导。结果 培训结业的学员在各方面有比较真显著变化,心态明显改变,知识明显提高、助人技巧明显增强、人际交往明显改善,总体上呈现出积极、友爱、乐观、向上的精神面貌。结论 在高校能够培训出合格的学生朋友心理辅导员,并成为高校学生心理健康教育网络的重要力量。  相似文献   
57.
目的 探讨中长跑有氧与无氧训练对血浆电解质及部分微量元素的影响 .方法 上海市及上海体院田径队中长跑运动员 ,根据个人运动专长 ,安排相应专项训练 ;12名进行有氧训练 ,14名进行无氧训练 ,分别在训练前及运动后即刻抽静脉血 ,检测血乳酸等电解质及微量元素铁、铜的水平 .结果 ①两组训练后 ,血乳酸、Na、Cl及无机磷(P)水平均显著升高 (p <0 .0 1) ;无氧组训练后 ,血清总钙 (Ca)及血清铁 (Fe)水平均显著升高 (p <0 .0 1) .②两组训练后 ,Cu水平显著下降 (p <0 .0 1,下降幅度均达 35 %以上 ) ;无氧组训练后 ,K水平有下降趋势 (p =0 .0 6 ) .③有氧组训练后 ,乳酸升高与K水平呈显著相关 ((r=- 0 .6 73,p <0 .0 5 ) ;无氧组训练后 ,乳酸升高与Mg水平显著相关 (r=0 .5 5 1,p<0 .0 5 ) ,与Na水平呈极显著相关 (r=0 .731,p <0 .0 1) .结论 ①有氧、无氧训练对电解质及微量元素水平的影响明显不同 .②无氧训练较有氧训练更需注意运动后电解质紊乱 ,尤需注意运动后血钙水平的升高及血钾水平的下降 .  相似文献   
58.
A polymorphic variant of the human angiotensin converting enzyme (ACE) gene was identified. The 'D' (rather than 'I') variant was associated with improvements in strength related to physical training. We set out to determine whether the response to different patterns of strength training might also differ. Ninty-nine Caucasian male non-elite athletes were randomly allocated into one of three groups: 31 non-training/control (CG: 31), single-set (SSG: 35) and multiple-set (MSG: 33). SSG and MSG trained three times a week for 6 weeks. Both training groups were underwent a strength-training program with two mesocycles (12-15 repetition maximum (RM) and 8-12 RM mesocycles). One RM loads in half squat and bench press were assessed before training and after the first and second mesocycles. ACE polymorphisms analysed by polymerase chain reaction (PCR) methods. Subjects with ACE II genotype in the MST group had improved strength development in 12-15 RM, while SST and MST groups had similar gains in 8-12 RM. Subjects with ACE DD genotype in both the SSG and the MSG had similar benefits from both 12-15 RM and 8-12 RM. Strength gains for subjects with ACE ID genotype in the SSG were similar to MSG gains in response to 8-12 RM loads but not with 12-15 RM loads. Additionally, subjects with DD genotype had superior strength gains in both strength training groups. Tailoring strength training programmes (single-set vs. multiple set) according to the athlete's ACE genotype may be advantageous.  相似文献   
59.
人际交往训练降低医学生心理应激反应的实验研究   总被引:3,自引:0,他引:3  
目的 探讨人际交往训练降低医学生心理应激反应的有效模式 ,以培养交往手段 ,促进身心健康 ,提高学习效率。方法 从云南中医学院中医专业 2 0 0 0级 8个班 ,41 2名学生中随机抽取 2个班 ,共 1 0 6人为被试对象 ,结合专业学习 ,在生理学课堂教学中贯穿人际交往训练 ,训练前后分别测查 90项症状自评量表 ( SCL-90 )和防御方式问卷 ( DSQ) ,并用 Q分类法检验被试课前和课后自我评价。最后 ,对被试和其余 6个班的学生进行生理测验 ,并对测验成绩进行比较。结果 被试在交友信心、乐观豁达、口头表达、积极接纳、说服技巧方面均比训练前有显著和极显著提高 ;且考前心理应激反应明显降低 ,防御方式趋向成熟 ,测验及格率高于其余 6个班。结论 结合专业进行人际交往训练可在近期内改善医学生的心理健康水平 ,有利于提高学习效率 ,深受大学生欢迎  相似文献   
60.
Summary The apparent efficiency of sub-maximum exercise tends to be lower in subjects with a large aerobic power. This is probably an artefact arising from neglect of the oxygen debt in the calculation of mechanical efficiency. Changes in the extent of oxygen debt can obscure an increased skill of performance with training. Efficiency is improved by repetition of a given mode of exercise, but not by other forms of training. Habituation is greater during work than at rest, but even during work the change in pulse rate of young men does not exceed 2–5 beats/min over 5 experimental days. Habituation is lost if the test procedure is not repeated during training; this can complicate assessments of training from the response to sub-maximum exercise.  相似文献   
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