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991.
Du Pan syndrome is a rare condition comprising complex brachydactyly with fibular hypoplasia that is inherited in an autosomal recessive manner. This article describes experience gained through the management of four patients with this disorder. The surgical management of the upper limb abnormalities is discussed and a detailed timetable for their treatment is suggested.  相似文献   
992.
OBJECTIVE: This study assessed the long-term mental health effects of the nuclear accident at Chernobyl. METHOD: Two population samples (N = 3,044), one from the Gomel region, close to the accident site, and one from Tver, 500 miles away, were studied 6 1/2 years after the event with the use of a variety of self-report questionnaires and a standardized psychiatric interview. RESULTS: The prevalence of psychological distress and DSM-III-R psychiatric disorders was exceptionally high in both regions. Scores on the self-report scales were consistently higher in the exposed region; however, a higher risk of DSM-III-R psychiatric disorders could be demonstrated only among women with children under 18 years of age in the exposed region. CONCLUSIONS: A substantial long-term mental health effect of the Chernobyl incident was demonstrated, mainly at a subclinical level.  相似文献   
993.
994.
OBJECTIVE: To determine anatomic patterns and clinical importance of increased radiopharmaceutical uptake in bones of horses used for show jumping, hunting, and eventing. DESIGN: Retrospective study. ANIMALS: 141 horses evaluated because of lameness. PROCEDURE: Medical records were reviewed, and information on results of physical examination, radiography, and scintigraphy were obtained. Scintigrams were evaluated to identify areas of increased radio-pharmaceutical uptake. RESULTS: 834 areas of increased radiopharmaceutical uptake were identified. Scintigraphy of the vertebral column was performed in 78 horses, and 50 had areas of increased radiopharmaceutical uptake involving the spinous processes. Scintigraphy of the proximal phalanx of the forelimb was performed in 88 horses. Similarly, scintigraphy of the proximal phalanx of the hind limb was performed in 99 horses, and scintigrams of 374 proximal phalanges were available for review. One hundred fifty-five scintigrams had areas of increased radiopharmaceutical uptake. Scintigraphy of the tarsal joint was performed in 99 horses, and scintigrams of 198 joints were available for review. Eighty-five had areas of increased radiopharmaceutical uptake. Overall, 214 of 834 areas of increased radiopharmaceutical uptake were definitively associated with lameness. CLINICAL IMPLICATIONS: Results of this study suggest that jumping creates unique stresses on the bones of horses. The distinctive patterns of increased radiopharmaceutical uptake identified in this study suggest that horses used for jumping may have a predilection to develop orthopedic disease at specific sites distinct from those in racehorses.  相似文献   
995.
Neurobiology of retinal dopamine is reviewed and discussed in relation to degenerative states of the tissue. The Introduction deals with the basic physiological actions of dopamine on the different neurons in vertebrate retinae with an emphasis upon mammals. The intimate relationship between the dopamine and melatonin systems is also covered. Recent advances in the molecular biology of dopamine receptors is reviewed in some detail. As degenerative states of the retina, three examples are highlighted: Parkinson's disease; ageing; and retinal dystrophy (retinitis pigmentosa). As visual functions controlled, at least in part, by dopamine, absolute sensitivity, spatial contrast sensitivity, temporal (including flicker) sensitivity and colour vision are reviewed. Possible cellular and synaptic bases of the visual dysfunctions observed during retinal degenerations are discussed in relation to dopaminergic control. It is concluded that impairment of the dopamine system during retinal degenerations could give rise to many of the visual abnormalities observed. In particular, the involvement of dopamine in controlling the coupling of horizontal and amacrine cell lateral systems appears to be central to the visual defects seen.  相似文献   
996.
1,3-Butadiene and styrene are oxidized, in part, by cytochrome P450 2E1 and have been shown to metabolically interact in rodents exposed by inhalation to mixtures of both compounds. Because the reactive metabolites of butadiene and styrene are thought to be responsible for the toxicity of each compound, metabolic interactions may alter the response in animals exposed to mixtures of butadiene and styrene compared with the response in animals exposed to butadiene alone or styrene alone. The purpose of this study was to quantitate alterations in genotoxicity and cytotoxicity in male B6C3F1 mice exposed to mixtures of butadiene and styrene. Male B6C3F1 mice were exposed to 6.25, 62.5, 200, or 625 ppm butadiene alone, 50 ppm styrene alone, or mixtures of 6.25, 62.5, 200, or 625 ppm butadiene and 50 ppm styrene. Genotoxicity was assessed by quantitating the frequency of micronucleated polychromatic erythrocytes in bone marrow. Cytotoxicity was assessed by counting total spleen and thymus cells and by quantitating the frequency of polychromatic erythrocytes in the peripheral blood. Butadiene and mixtures of butadiene and styrene were genotoxic in mice, as shown by a significant increase in the frequency of micronucleated polychromatic erythrocytes. The increased frequency following exposure to mixtures of butadiene and styrene was not significantly different compared with the frequency following exposure to butadiene alone. Styrene and mixtures of butadiene and styrene were cytotoxic in mice, as shown by significantly decreased number of spleen cells. Exposure to mixtures of butadiene and styrene with butadiene concentrations of 62.5 or 625 ppm significantly reduced the number of thymus cells. Exposure to 200 ppm or 625 ppm butadiene alone, or to mixtures of 200 ppm or 625 ppm butadiene and 50 ppm styrene, significantly reduced the frequency of polychromatic erythrocytes in the peripheral blood. The results of the study demonstrate that exposure to mixture of butadiene and styrene does not reduce the respective genotoxicity of butadiene or cytotoxicity of styrene.  相似文献   
997.
AIMS: The objective of this study was to quantify the risk of serious blood and skin disorders associated with co-trimoxazole. METHODS: We conducted a population-based cohort study of serious blood and skin disorders requiring hospitalization among otherwise healthy users of co-trimoxazole at Group Health Cooperative and Puget Sound (GHC). RESULTS: During the years 1987 to 1993 we found six cases of co-trimoxazole-associated blood disorders and three cases of co-trimoxazole-associated skin disorders yielding risks of 5.6/100,000 (95% CI 2.6-12.2) and 2.8/100,000 (95% CI 0.9-8.2) respectively. In all cases found there was prompt recovery after discontinuation of co-trimoxazole. We found no cases of toxic epidermal necrolysis. CONCLUSIONS: We conclude that the risk of blood and skin disorders associated with the use of co-trimoxazole leading to hospitalization is low.  相似文献   
998.
BACKGROUND: Several published experimental results have shown that cultures of suspended bacteria exhibit increased growth in the spaceflight environment. HYPOTHESIS AND METHODS: To test whether these differences were due to fluid mechanics and not cellular effects, E. coli and B. subtilis were grown on agar cultures under static, agitated, and rotated conditions in the laboratory, and under low-gravity conditions on four Space Shuttle flights. Growth experiments were terminated with glutaraldehyde, and individual cells were counted after quantitative elution from the agar. RESULTS: The spaceflight results, in conjunction with static, rotation, and agitation experiments indicate that E. coli and B. subtilis cultures on agar, unlike their suspension grown counterparts, do not experience heightened final cell concentration when the inertial environment is changed. CONCLUSIONS: This finding points to fluid dynamics and extracellular transport phenomena and not cellular dynamics as the most likely cause of previously reported increases in bacterial growth in microgravity.  相似文献   
999.
The rate of information processing, as revealed in measures of reaction time, slows with advancing age and this slowing is most evident as processing complexity increases. This phenomenon, known as the Age-Complexity effect, has been attributed to general changes in the speed of processing that affect all components of processing indiscriminantly, both within and across tasks in a particular processing domain. That the slowing is thought to be task- and process-independent has led to the additional inference that it reflects reductions in a general processing resource. On the basis of converging evidence identified in a review of both behavioral and chronopsychophysiological studies, we argue that the slowing induced by older age is not generalized, but rather is both task-dependent and process-specific and, as such, cannot be explained in terms of a diminished general processing resource. We close by speculating that elements of the age-induced slowing can be interpreted within the context of the cognitive-energetical model.  相似文献   
1000.
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