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991.
In the revelation effect, the probability of labeling a target or a lure as "old" on item recognition tests increases if just prior to their recognition judgment, participants first identify a disguised version of the test item. The same occurs with interpolated tasks that occur just prior to a recognition judgment if the task shares constituents with the test items. One explanation of this test bias is an increased feeling of familiarity that comes from the identification stage preceding the recognition judgment (e.g., D. C. LeCompte, 1995; C. R. Lou, 1993). This study's finding in 4 experiments that 2-alternative forced-choice recognition either yields no effects of revelation or an "antirevelation" effect, even when both items were studied or nonstudied, is incongruent with this explanation. The authors argue that revelation decrements familiarity, and this results in a more liberal criterion shift. They also argue that their theory is more consistent with previous empirical data.  相似文献   
992.
Skin does more than present one's "face" to the world; it plays a vital role in the maintenance of physical and mental health. As our most ancient interface, skin retains the ability to respond to both endogenous and exogenous stimuli, sensing and integrating environmental cues while transmitting intrinsic conditions to the outside world. As such, it has long been a target for the application of both medical and nonmedical therapies of healthy and diseased states. Our understanding of how the skin and topical therapies affect health is in its infancy. Conversely, we known little of how our internal systems affect our skin. By exploring an elaborate web of neuro-immuno-cutaneous-endocrine (NICE) phenomena, we seek to shed light on the generally acknowledged, but inadequately defined, relationship between mental and physical health. We use skin as our window, noting some of the biological mediators linking nervous, immune, cutaneous, and endocrine functions. It is likely that these mediators are important in homeostasis, and that they affect several dermatologic and psychiatric conditions.  相似文献   
993.
The possibility that the experiences of the "hidden" child survivors of the Holocaust (those who survived outside of the concentration camps during the Nazi occupation) had a pathological effect on their offspring was examined by comparing volunteer, matched samples of adult children of "hidden" child survivors of the Holocaust with adult children of nontraumatized U.S.-born Jewish parents on personality variables measured by the Sixteen Personality Factor Questionnaire (Cattell, Eber, & Tatsuoka, 1970). The MANOVA results indicated that there were no differences in the personality characteristics of the two groups.  相似文献   
994.
PURPOSE: This study was designed to develop improved criteria for the diagnosis of infective endocarditis and to compare these criteria with currently accepted criteria in a large series of cases. PATIENTS AND METHODS: A total of 405 consecutive cases of suspected infective endocarditis in 353 patients evaluated in a tertiary care hospital from 1985 to 1992 were analyzed using new diagnostic criteria for endocarditis. We defined two "major criteria" (typical blood culture and positive echocardiogram) and six "minor criteria" (predisposition, fever, vascular phenomena, immunologic phenomena, suggestive echocardiogram, and suggestive microbiologic findings). We also defined three diagnostic categories: (1) "definite" by pathologic or clinical criteria, (2) "possible," and (3) "rejected." Each suspected case of endocarditis was classified using both old and new criteria. Sixty-nine pathologically proven cases were reclassified after exclusion of the surgical or autopsy findings, enabling comparison of clinical diagnostic criteria in proven cases. RESULTS: Fifty-five (80%) of the 69 pathologically confirmed cases were classified as clinically definite endocarditis. The older criteria classified only 35 (51%) of the 69 pathologically confirmed cases into the analogous probable category (p < 0.0001). Twelve (17%) pathologically confirmed cases were rejected by older clinical criteria, but none were rejected by the new criteria. Seventy-one (21%) of the remaining 336 cases that were not proven pathologically were probable by older criteria, whereas the new criteria almost doubled the number of definite cases, to 135 (40%, p < 0.01). Of the 150 cases rejected by older criteria, 11 were definite, 87 were possible, and 52 were rejected by the new criteria. CONCLUSION: Application of the proposed new criteria increases the number of definite diagnoses. This should be useful for more accurate diagnosis and classification of patients with suspected endocarditis and provide better entry criteria for epidemiologic studies and clinical trials.  相似文献   
995.
This work presents a comparison of probabilistic and deterministic health risk estimates based on data from an industrial site in the northeastern United States. The risk assessment considered exposures to volatile solvents by drinking water ingestion and showering. Probability densities used as inputs included concentrations, contact rates, and exposure frequencies; dose-response inputs were single values. Deterministic risk estimates were calculated by "reasonable maximum exposure" (RME) approach recommended by the EPA Superfund program. The RME noncarcinogenic risk fell between the 90th and the 95th percentile of the probability density; the RME cancer risk fell between the 95th percentile and the maximum. These results suggest that in this case (1) EPA's deterministic RME risk was reasonably protective, (2) results of probabilistic and deterministic calculations were consistent, and (3) commercially available software Monte Carlo software effectively provided multiple risk estimates recommended by recent EPA guidance.  相似文献   
996.
Transport of Relational Structures in Groups of Diffeomorphisms   总被引:1,自引:0,他引:1  
This paper focuses on the issue of translating the relative variation of one shape with respect to another in a template centered representation. The context is the theory of Diffeomorphic Pattern Matching which provides a representation of the space of shapes of objects, including images and point sets, as an infinite dimensional Riemannian manifold which is acted upon by groups of diffeomorphisms. We discuss two main options for achieving our goal; the first one is the parallel translation, based on the Riemannian metric; the second one, based on the group action, is the coadjoint transport. These methods are illustrated with 3D experiments.
Laurent YounesEmail:
  相似文献   
997.
A "problem solving case" method of teaching practical pathology is described, illustrated and compared with more traditional teaching methods. This method offers many advantages-the most important being that it shows the effect of pathological lesions in an actual patient, thus emphasizing the relevance of pathology to clinical medicine. Other advantages are that self-assessmetn is encouraged; guidance is given on the depth of knowledge expected from a student; student response is favourable; no elaborate or expensive equipment is required; the method is economic in the use of staff time, and it is very flexible in use in terms both of time and place.  相似文献   
998.
The major reason for treating hypertension is to avoid complications of the disease as it affects "target organs." Treatment of the blood pressure is not the only way to avoid these complications, but it is part of the total practice of preventive medicine. Hypertension lasts for several decades in most patients, and there is time to destroy the patient through target organ effects or to save the patient through treatment. Diabetes, atherosclerosis, and other illnesses and operations pose special hazards to the patient with hypertension. Patients take many other drugs as well, and some of them react adversely with antihypertension medicines. Complications from blood pressure drugs involve nearly every organ system, more than most physicians can remember. These may be dose-related and can often be avoided by using smaller doses of more than one drug. Certain problems occur so frequently that they should be learned well. The physician should bear in mind that whatever develops may be due to the antihypertensive therapy. On the whole, however, medications for treatment of hypertension are remarkably safe and free from side effects.  相似文献   
999.
Fusion of plasma membranes between Chlamydomonas reinhardtii gametes has been studied by freeze-fracture electron microscopy of unfixed cells. The putative site of cell fusion developes during gametic differentiation and is recognized in thin sections of unmated gametes as a plaque of dense material subjacent to a sector of the anterior plasma membrane (Goodenough, U.W., and R.L. Weiss. 1975.J. Cell Biol. 67:623-637). The overlying membrane proves to be readily recognized in replicas of unmated gametes as a circular region roughly 500 nm in diameter which is relatively free of "regular" plasma membrane particles on both the P and E fracture faces. The morphology of this region is different for mating-type plus (mt+) and mt- gametes: the few particles present in the center of the mt+ region are distributed asymmetrically and restricted to the P face, while the few particles present in the center of the mt- region are distributed symmetrically in the E face. Each gamete type can be activated for cell fusion by presenting to it isolated flagella of opposite mt. The activated mt+ gamete generates large expanses of particle-cleared membrane as it forms a long fertilization tubule from the mating structure region. In the activated mt- gamete, the E face of the mating structure region is transformed into a central dome of densely clustered particles surrounded by a particle-cleared zone. When mt+ and mt- gametes are mixed together, flagellar agglutination triggeeeds to fuse with an activated mt- region. The fusion lip is seen to develop within the particle-dense central dome. We conclude that these mt- particles play an active role in membrane fusion.  相似文献   
1000.
Cardiac performance was evaluated in 12 infants with isolated total anomalous pulmonary venous return. Four had significant pulmonary venous obstruction and severe pulmonary hypertension (group A). Eight had no obvious venous obstruction, and the pulmonary pressures were lower (group B). In all subjects, right ventricular end-diastolic volume was increased (197% of predicted normal) and its ejection fraction was normal. Left ventricular volume was, generally speaking, still in the normal range (87% of predicted normal); however, its ejection fraction was reduced (0.57 vs normal of 0.73) and left ventricular output was low (3.08 L/min/m2 vs normal of 3.98). Left atrial volume was consistently small (53% of predicted normal) with an appendage of normal size. The infants in group A had smaller chamber volumes/m2 BSA than those in group B. Left atrial function was abnormal, characterized by reduced reservoir function and a greater role as "conduit" from right atrium to left ventricle. Left atrial size was not found to be critical in the surgical repair of TAPVR. Cardiac function is restored to normal following surgery.  相似文献   
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