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991.
The past decade has seen renewed interest in the neuropathology of schizophrenia. The advent of new postmortem techniques and functional imaging, along with a greater understanding of the neuropsychology of schizophrenia, have provided many new clues to the nature of the underlying brain dysfunction in this disorder. There has also been a greater understanding of the presence of severe cognitive dysfunction among many elderly persons with schizophrenia. In this article, a series of investigations are described that seek to answer basic questions about the neuropathology of schizophrenia, in particular as it pertains to cognitive impairment. The first study describes neuropathological findings in 100 consecutively autopsied persons with schizophrenia, the majority of whom had had detailed antemortem assessments. Results from this first study prompted the conclusion that schizophrenia is not characterized by classical, histologically identifiable neuropathology. Moreover, most cases of dementia in schizophrenia are probably not the result of neuropathologically identifiable dementing illnesses. The next four studies examined chemical markers that are altered in Alzheimer's disease and some other dementing conditions and have also been suggested to be abnormal in schizophrenia: choline acetyltransferase, catecholamines and indolamines, neuropeptides, and synaptic proteins. Schizophrenia cases as a group did not show a cholinergic deficit; nor did they differ from elderly comparison cases with respect to cortical catecholamines and indolamines. Among the schizophrenia cases, however, cognitive impairment was negatively correlated with choline acetyltransferase activity. Those with cognitive impairment showed evidence of cortical noradrenergic and serotonergic deficits. Neuropeptide deficits were also present in schizophrenia, but their pattern differed from that seen in Alzheimer's disease. Increased synaptic protein activity was found in the cingulate cortex of persons with schizophrenia, and this activity was correlated with schizophrenia symptoms. From this second series of studies, it was concluded that some biological measures in schizophrenia may be related to cognitive impairment (e.g., cortical amines), whereas others may be related to diagnosis (e.g., neuropeptide deficits). In addition, synaptic organization may correlate with schizophrenia symptoms.  相似文献   
992.
Recent evidence suggests that the cost as well as the morbidity associated with the maintenance of hemodialysis access is increasing rapidly; currently, the cost exceeds 1 billion dollars and access related hospitalization accounts for 25% of all hospital admissions in the U.S.A. This increase in cost and morbidity has been associated with several epidemiological trends that may contribute to access failure. These include late patient referral to nephrologists and surgeons, late planning of vascular access as well as a shift from A-V fistulaes to PTFE grafts and temporary catheters, which have a higher failure rate. The reasons for this shift in the types of access is multifactorial and is not explained by changes in the co-morbidities of patients presenting to dialysis. Surgical preference and training also appear to play an important role in the large regional variation and patency rate of these PTFE grafts. We propose a program for early placement of A-V fistulae, a continuous quality improvement, multidisciplinary program to monitor access outcome, the development of new biomaterials, and a research plan to investigate pharmacological intervention to reduce development of stenosis and clinical interventions to treat those that do develop, prior to thrombosis.  相似文献   
993.
Studies on 33 anesthetized white mice were used to determine the motor representation of facial muscles and limb muscles by an intracortical microstimulation method. Microstimulation produced predominantly ipsilateral movement responses of facial muscles and contralateral responses in fore- and hindlimb muscles. Low-threshold stimulation in the left and right hemispheres showed a clear asymmetry of the motor representation of the facial muscles. Movement responses of the hindlimbs were obtained on microstimulation of the frontal regions of the neocortex, demonstrating the existence of multiple motor representations of muscles in the neocortex.  相似文献   
994.
OBJECTIVE: To determine whether administration of bacille Calmette-Guérin (BCG) vaccination to newly diagnosed IDDM patients can help preserve C-peptide secretion over the subsequent 18 months. RESEARCH DESIGN AND METHODS: Twenty-six IDDM patients, all of whom had been diagnosed within the previous year, had basal C-peptide levels >0.06 nmol/l, and had negative reactions to Mantoux's test, were randomized pairwise as they presented and were given either 0.1 ml (100 microg) BCG vaccine or 0.1 ml saline intradermally Both the patients and the investigators were blinded to the treatment. Fasting and glucagon-induced C-peptide levels and HbA1c were measured in all patients at enrollment and at 1, 3, 6, 9, 12, and 18 months after vaccination, and insulin dose was recorded at each visit. RESULTS: At enrollment, there was no significant difference in age, duration of diabetes, insulin dose, HbA1c, or fasting C-peptide levels between the BCG-vaccinated and control groups. The mean basal and stimulated C-peptide levels in the BCG-treated group did not differ significantly from those in the control group at any time during the 18 months of follow-up, and there was no difference in insulin dose or HbA1c at any time between the groups. CONCLUSIONS: BCG vaccination in children who have been recently diagnosed with IDDM does not affect the progressive decline in C-peptide levels or alter the clinical course of the disease.  相似文献   
995.
996.
A distinct form of aplasia cutis congenita presenting as linear facial skin defects has been described under a variety of names as Xp deletion syndrome. MIDAS (microphthalmia, dermal aplasia and sclerocornea) syndrome, MLS (microphthalmia and linear skin defects) and Gazali-Temple syndrome. The syndrome is lethal in males, and its severity in females varies from a relatively mild residual facial scarring with short stature to lethal developmental organ malformations. A new case with peculiar ultrastructural findings is presented. A review of the literature suggests that these associations represent a series of contiguous-gene syndromes.  相似文献   
997.
998.
Spoken words have a rich structural organization in memory, consisting of syllabic and subsyllabic representations. A phoneme monitoring paradigm, in which the target phoneme occurs more frequently in one syllabic position than another (e.g., onset of the 2nd syllable vs. the coda of the 1st syllable: neu-tral vs. nut-meg; C. Pallier, N. Sebastian-Galles, T. Felguera, A. Christophe, & J. Mehler, 1993) was used to explore the formation of syllabic structure during word processing. Experiment 2 investigated how a recognition system that uses syllabic structure processes words with unclear syllable boundaries (e.g., pa-lace or pal-ace?). Two methodological issues were explored: The importance of a baseline condition for measuring effects of induction (Experiment 1) and the form of the representation used in the induction paradigm (Experiment 3). Findings suggest that syllabic structure begins to form early in word processing, and they demonstrate the adequacy of the induction procedure for measuring such processes.  相似文献   
999.
Nursing has been concerned primarily with the visible aspects of health promotion and has shown little regard for what is invisible. Yet the hidden ideology powerfully shapes current approaches to health promotion. This paper examines and makes visible the ideology of individual responsibility which is embedded in individualistic health promotion, the primary orientation to health promotion. Ways in which this ideology is perpetuated within nursing curricula are described. Concrete strategies are proposed that may be considered by nurse educators as they seek to prepare students in health promotion, with particular emphasis on strategies that highlight its ideological underpinnings.  相似文献   
1000.
Certain constitutional chromosomal abnormalities increase the risk of malignancy and/or decrease treatment tolerance. We identified two patients with the XYY syndrome among a total of 444 male children with acute lymphoblastic leukemia who had complete cytogenetics studies. In both cases, the leukemic cell karyotype suggested a constitutional XYY abnormality that was confirmed in studies of lymphocytes obtained during remission. The incidence rate in our series is higher than that of the XYY syndrome in the general population (0.0045 vs. 0.001), but not significantly so. This finding and a literature review failed to confirm an increased frequency of the XYY syndrome among children with acute lymphoblastic leukemia. Both of our patients remain in remission 24 and 28 months, respectively, postdiagnosis. Their tolerance of intensive treatment, including high-dose methotrexate, suggests that the untoward treatment toxicity seen in patients with chromosomal abnormalities such as trisomy 21 does not extend to the XYY syndrome.  相似文献   
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