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41.
Lester S. King 《The Journal of experimental medicine》1940,71(1):107-112
In mice affected with equine encephalomyelitis, the first pathological disturbance in infant animals is an inflammatory reaction, which is usually less pronounced in adult animals. A characteristic type of parenchymal damage appears to be independent of the inflammation. In such foci of injury there is initially a vacuolation of intercellular tissue. Neurones in such areas are at first intact, later show cytoplasmic changes, and finally nuclear alterations. Complete disintegration of tissue and all its elements may be the end result. 相似文献
42.
Sudden occlusion of the left anterior descending branch approximately 2 cm. below the ostium of the left circumflex coronary artery in the dog''s heart produces a mortality rate of approximately 50 per cent. In dogs weighing approximately 15 kilos surviving more than 24 hours (average 1 week), an infarction is produced which almost invariably measures 5 x 5 cm. on surface. Following coronary sinus obturation such secondary sudden occlusion of the left anterior descending branch is followed either by no infarction or by a reduction in the size of the infarct. The success of the procedure, quite apart from the mortality rate, depends upon the completeness of the coronary sinus obturation. On the other hand, sudden and complete coronary sinus obturation by itself is associated with a high operative mortality and apparently does not affect the mortality rate following subsequent sudden left anterior descending branch occlusion. Partial persistent obturation of the coronary sinus, however, is in itself associated with a low operative mortality. Furthermore, its experimental production in dogs appears to lower the mortality rate following subsequent sudden occlusion of the left anterior descending branch and to diminish the extent of the infarction. In the introduction to this report it was pointed out that there are three important desiderata to the problem of improving the coronary circulation in the human heart. The findings herein reported fulfill these requisites to an encouraging degree. It has been shown that following the outlined procedures, a functional increase in the blood supply to the heart can be produced in a significant proportion of experimental animals, this varying with the nature of the experimental procedure. The manipulation is simple, can be performed in the dog within approximately 20 minutes, and does not lead to appreciable pericardial adhesions. Increase in the nutrition of the myocardium is noted 1 week after the experimental procedure. Although no experiments employing sudden left anterior descending coronary branch occlusion were carried out sooner than 1 week, there is available anatomic evidence that within possibly 24 hours after coronary sinus occlusion a dilatation of the vascular bed occurs. In subsequent experiments attempts will be made to determine whether this early vascular dilatation is adequate to compensate for subsequent sudden left anterior descending branch occlusion. A discussion is given of the results following various coronary sinus occlusion procedures in which it is indicated that it is desirable to produce a partial or gradual occlusion in order to lower the mortality rate both of the initial procedure as well as of the subsequent sudden arterial occlusion. Experiments thus far reported on cardiopexy operations are lacking in evidence that they are associated with appreciable improvement in the vascular nutrition of the myocardium. 相似文献
43.
The effect of war on the suicide rate and on the relative likelihood of suicide as a proportion of total personal aggression was examined in the United States for the time period from 1933 to 1986. Once unemployment was controlled for, no effect of war was detected. 相似文献
44.
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46.
The factor structure of the Suicide Opinion Questionnaire (SOQ) was investigated in 2 studies. In the first study, the SOQ was administered to 568 participants to investigate the relative strength of 3 competing latent structure models previously identified in the literature. Confirmatory factor analyses provided no support for any of the prior models. An exploratory factor analysis of these data resulted in a weak 2-factor structure accounting for only 15.33% of the common variance. In the second study, this 2-factor structure was evaluated using SOQ data from 288 college students. Confirmatory factor analysis results failed to support the 2-factor model. Based on these results, the authors recommend that future research efforts should focus on developing a more contemporary and psychometrically sound measure of attitudes toward suicide. 相似文献
47.
Building on a recent paper by Lester (1997) on shame and suicide, a case is presented of a woman who made a serious attempt to kill herself, motivated in large part by shame. The therapeutic strategies employed are described, and the case brought to a successful resolution. 相似文献
48.
In a study of 78 undergraduates, 2 factors of music preferences were identified--(a) heavy metal and rock and (b) rap versus country. Music preferences contributed to the prediction of suicidal ideation only in the male students. 相似文献
49.
Charles M Lombardi Alison D Silhanek Fiona G Connolly Lester N Dennis 《The Journal of foot and ankle surgery》2002,41(2):96-103
The purpose of this study was to examine the effect of first metatarsophalangeal arthrodesis on the sagittal plane orientation of the first ray and the medial longitudinal arch. Lateral weightbearing radiographs of 48 patients (54 feet) having undergone the procedure were retrospectively reviewed. Patients were separated into three groups based on their preoperative diagnosis: hallux rigidus, hallux valgus, or rheumatoid forefoot deformity. First metatarsal declination, talometatarsal, talar declination, calcaneal inclination, and talocalcaneal angles were measured on pre- and postoperative radiographs. Multivariate analysis of variance determined that there was a significant postoperative change (p < .001) in angular measurements, particularly in the first metatarsal declination, talometatarsal, and talocalcaneal angles. There was also a significant difference (p < .01) in the angular measurements between the hallux rigidus group and the other two groups. However, the amount of change from pre- to postoperatively did not vary significantly between the groups. A calculation of Pearson correlation coefficients found no significant correlation between the hallux dorsiflexion angle and changes in angular measurements. The radiographic changes found in this study support Hicks' windlass model: fixed dorsiflexion of the hallux causes plantarflexion of the first ray and an increase in the medial longitudinal arch. 相似文献
50.
Lester M. Arguelles Xiaobin Wang Binyan Wang Hakan Demirtas Jianhua Yang Zhiping Li Liuliu Wang Xue Liu Genfu Tang Houxun Xing Xiping Xu 《Archives of osteoporosis》2007,2(1-2):7-20
Introduction This report examines the relationship of body mass index (BMI), percent body fat (%BF), and bone mass in a cohort of male
and female twins recruited from Anhui province, China, ages 6–18 years—577 male pairs (mean age = 11.4) and 478 female pairs
(mean age = 11.6).
Methods Whole body bone mineral content (WBMC) in (g), whole body bone area (WBA) in (cm2), and %BF were measured using DEXA (Lunar Prodigy, USA). Regression analysis of within-pair differences was used to assess
the strength of the association, and the analysis was stratified by gender and age group, where age cut-offs were based on
ages at spermarche or menarche estimated from large population based studies in China. Males were stratified at ages before
14 and age 14–18, and females at ages prior to 12 and age 12–18.
Results Univariately, BMI and %BF were associated with WBMC and WBA in the younger males and females, and in older males; %BF was
significant only in older females. Multivariate models included both BMI and %BF. Among the younger males, age < 14, BMI and
%BF were significantly associated with WBMC and WBA. In the younger females, age < 12, %BF was only significant to WBA. In
the older age group, only BMI was significant to WBMC and WBA in females, but in males, BMI was positively associated, and
%BF was negatively associated with both bone measures.
Discussion These findings show that association between BMI and %BF and bone mass differ across gender and developmental stages, and
%BF appears to be beneficial at younger ages, but detrimental or non-beneficial at older ages of development. 相似文献