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61.
A recombinant human antithrombin (rhAT; generic name: antithrombin Alfa) has recently been developed. A 37 year-old parturient with hereditary antithrombin deficiency, receiving rhAT infusion therapy, who successfully received an epidural catheter for analgesia and anesthesia during labor and cesarean delivery, is presented.  相似文献   
62.
Xanthine derivatives relax adult airway smooth muscle (ASM). To determine whether caffeine and theophylline relax preterm ASM contracted by acetylcholine, 27 tracheal rings obtained from seven preterm lambs (120-135 d gestation) were studied. ASM was contracted using 10(-5) M acetylcholine (control) after the muscle was stretched to the length at which maximum active tension was developed isometrically. Concentration-effect curves for each xanthine were obtained by cumulative addition of the drug. Theophylline produced a significant decrease (p less than 0.001) in active tension at each dose, whereas caffeine significantly increased (p less than 0.001) active tension at 10(-4) and 10(-3) M concentrations. Addition of caffeine and theophylline to previously uncontracted ASM did not alter tension. Thus, it appears that, in contrast to their effect on adult ASM, the xanthine derivatives caffeine and theophylline have differential effects on prestimulated ASM in preterm lambs. These findings raise important questions about various aspects of the current therapeutic use of caffeine and theophylline.  相似文献   
63.
While many reports have documented the effects of hydrocephalus on the ependyma and periventricular white matter, primarily in adult animal models, little is known about alterations specific to neurons. The present study has evaluated qualitatively the effects of hydrocephalus on the neurons and vasculature of the cerebral cortex in a neonatal animal model. The cisterna magna of 4 to 11-day-old kittens was injected with a solution of 25% kaolin to induce hydrocephalus. Ultrasonographic evidence of hydrocephalus was noted within 3-5 days of injection. Hydrocephalus progressed until day 18-25 postinjection when the animals were sacrificed. The cytologic and cytoarchitectural changes within the cortical mantle of affected animals were compared with control age-matched counterparts who had undergone intracisternal saline injections. Areas 4 (primary motor), 22 (association) and 17 (primary visual sensory) were examined light microscopically. Neurons from hydrocephalic brains exhibited 3 types of pathological response. Pyknotic somata were shrunken, disoriented and so hyperchromatic that neither nuclei or nucleoli could be delineated. Reactive somata were also shrunken and hyperchromatic, but nuclei and nucleoli could still be observed. Many neurons contained an abundance of vacuoles, giving their somata a flocculent appearance; these cells were termed 'spongy' neurons. Both normal and pathological neurons were smaller and disoriented, with a considerable decrease in neurons noted in areas 22 and 17 from severely hydrocephalic animals. The deeper cortical layers were more affected than the more superficial laminae in that more reactive and pyknotic neurons were present in layers V and VI. As the ventriculomegaly became more severe, changes could be observed in neurons within layers II and III. Furthermore, the cerebral vasculature exhibited a decrease in the number of vessels and a preponderance of profiles oriented parallel to the meningeal surface. The severity of these effects followed a rostral to caudal gradient, such that the occipital cortex demonstrated the most damage. These results suggest that both the motor deficits and the subtle cognitive deficiencies seen with hydrocephalus may be attributed to perturbation of neuronal and vascular elements in the cerebral cortex.  相似文献   
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65.
A study of Eustachian tube measurements in infants and children is presented. The study included 33 Eustachian tubes from normal temporal bones and 10 Eustachian tubes from temporal bones harbouring acute otitis media. The temporal bones underwent histologic serial sectioning. The lumen of the Eustachian tube's first portion, i.e. the pharyngeal part, was measured with the aid of a grid mounted on a microscope. These measurements show: A. The Eustachian tube lumen grows and enlarges to a small extent with age. B. Each age group presents a considerable variation in the range of area of the lumen comparable with the natural biological distribution. C. No statistical difference was found between the size of the pharyngeal portion of the lumen of the Eustachian tube from temporal bones which had acute otitis media and those coming from non-pathological ears. This comparison took into consideration age and physiological distribution. These findings are similar to our earlier findings regarding the isthmic region.  相似文献   
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67.
The end-stage renal disease (ESRD) population is aging, and currently approximately 50% of patients treated with maintenance dialysis are more than 65 years old. With advancing age comes challenges to maintaining the nutritional status of these patients. As patients get older, purchasing and preparing food may become more difficult. In addition, appetite may decrease, the occurrence of intercurrent illnesses may become more frequent, and nutrient requirements change. Mobility may decline, as well as cognitive function, and the combination of several of these factors may result in malnutrition. Since malnutrition has been demonstrated to impact survival in dialysis patients of all ages, appropriate attention to nutritional status and its management is essential for the elderly dialysis patient. This article reviews the issues associated with the maintenance of good nutrition in the elderly dialysis patient and describes the potential causes of malnutrition in these patients. It also reviews the nutrient requirements for older dialysis patients (which differ somewhat from those of younger patients), as well as the assessment of their nutritional status. Finally, recommendations for management of nutrition in the elderly dialysis patient are discussed.  相似文献   
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69.
This article introduces a four-part series on outcome scales used in Alzheimer's disease drug trials. First, it discusses the division of scales into four domains: cognition, functional ability/quality of life, behavior/mood, and global. Within each domain, the shortcomings of existing literature reviews are outlined, and the need for a more coherent view of the psychometric properties of the scales is emphasized. Second, the key concepts of reliability, validity, and responsiveness to change are defined and explained. This explanation also provides an overview of the statistical techniques used to assess measurement properties. Finally, the methods used to select the scales for review in the subsequent articles are explained, and each article is briefly introduced.  相似文献   
70.
OBJECTIVE: To examine the relationships among exposure to violence; tobacco, alcohol, and other substance use; depression; church attendance; and the use of violence among very young adolescents. METHODS: An 86-item confidential questionnaire was administered to 722 sixth grade students (mean age = 11.9+/-0.8 years) attending 4 middle schools serving neighborhoods in and around public housing. RESULTS: Boys had a higher mean violence scale score than girls (P < or =.0001), and students living in public housing had higher violence scale scores than other students (P< or =.0001). Self-reported use of violence was significantly associated with exposure to violence (r =.45); age (r =.28); frequency of church attendance (r = -.14); depression (r =.28); the probability of being alive at age 25 (r = -.09); the frequency of use of cigarettes (r =.39), alcohol (r =.37), and multiple substances (r =.38); and interest in a gang (r =.37). When all of these variables were analyzed with multiple linear regression, multiple substance use, exposure to violence, interest in a gang, male gender, cigarette smoking, and depression level accounted for 49.7% of the variation in the use of violence scale. CONCLUSION: Recent multiple substance use and lifetime exposure to violence and victimization were the strongest correlates with the frequency that these youth reported using violence and carrying weapons.  相似文献   
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