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991.
The incidence of penetrating wounds of the chest is rising rapidly. Opinions continue to differ on their management. Our experience with 200 consecutive cases of stab wounds of the chest between 1972 and 1975 were reviewed. There were 176 males and 24 females. The average age was 31 years; about two-thirds of the patients were under 30. About 74% presented with hemothorax or hemopneumothorax; 21 presented with pneumothorax. Eleven per cent had associated intra-abdominal injuries. Seventy-nine per cent were successfully treated with tube thoracostomy. About 15% underwent thoracotomy, with three deaths (mortality, 10%); the mortality for cardiac wounds was 16%; overall mortality was 1.5%. The overall complication rate was 5.5%, most occurring in patients with cardiac wounds and associated intra-abdominal injuries. The average period of hospitalization was 6.5 days. Treatment was individualized. Indications for each course of therapy are discussed.  相似文献   
992.
The effect of temperature on the activity of galactosyl- and sialyltransferases of rat liver Golgi membranes and the galactosyltransferase of serum has been studied. Arrhenius plots for three enzymes were different. Sharp breaks in the curves, indicative of phase transitions were observed for sialyltransferase (28 degree C) of Golgi and galactosyltransferase (34 degree C) of serum but not for galactosyltransferase of Golgi. The activation energy was greater above the break (above 28 degree C) than below for sialyltransferase of Golgi; The activation energy was lower (above 34 degree C) for galactosyltransferase of serum than below. Electron microscopic freeze replicas showed a patchy distribution of particles which increased as the temperature was raised accompanied by smooth areas. This was interpreted as representing lateral phase separation of the membrane components.  相似文献   
993.
994.
Early in the development of implant technology it became apparent that conventional dental imaging techniques were limited for evaluating patients for implant surgery. During the treatment planning phase, the recipient bed is routinely assessed by visual examination and palpation, as well as by periapical and panoramic radiology. These two imaging modalities provide a two-dimensional image of mesial-distal and occlusal-apical dimensions of the edentulous regions where implants might be placed. When adequate occlusal-apical bone height is available for endosteal implants, the buccal-lingual width and angulation of the available bone are the most important criteria for implant selection and success. However, neither buccal-lingual width nor angulation can be visualized on most traditional radiographs. Although clinical examination and traditional radiographs may be adequate for patients with wide residual ridges that exhibit sufficient bone crestal to the mandibular nerve and maxillary sinus, these methods do not allow for precise measurement of the buccolingual dimension of the bone or assessment of the location of unanticipated undercuts. For these concerns, it is necessary to view the recipient site in a plane perpendicular to a curved plane through the arch of the maxilla or mandible in the region of the proposed implants. Implant dentists soon recognized that, for optimum placement of implants, cross-sectional views of the maxilla and mandible were the ideal means of providing necessary pre-operative information. Today, the two most often employed and most applicable radiographic studies for implant treatment planning are the panoramic radiograph and tomography. Although distortion can be a major problem with panoramic radiographs, when performed properly they can provide valuable information, and are both readily accessible and cost efficient. To help localize potential implant sites and assist in obtaining accurate measurements, it is recommended that surgical stents be used with panoramic radiographs. In simple cases, where a limited number of implants are to be placed, panoramic radiography and/or tomography may be used to obtain a view of the arch of the jaw in the area of interest. For complex, cases, where multiple implants are required, the CT scan imaging procedure is recommended. Because of its ability to reconstruct a fully three dimensional model of the maxilla and mandible, CT provides a highly sophisticated format for precisely defining the jaw structure and locating critical anatomic structures. The use of CT scans in conjunction with software that renders immediate "treatment plans" using the most real and accurate information provides the most effective radiographic modality currently available for the evaluation of patients for oral implants. To follow patients after implant surgery, DSR can be helpful by addressing the limitations of other radiographic modalities in detecting postoperative changes. By eliminating unchanged information, DSR allows the clinician's eye to focus on actual changes that have occurred between the recordings of two images.  相似文献   
995.
There has been an abundance of research on the connections of the mammillary bodies but the projections from the lateral mammillary nucleus to the anterodorsal thalamic nucleus has remained a gray area due to a dearth of material which directly addresses the details of this pathway. This study seeks to further define the nature of this particular nerve connection within the mammillothalmic tract. The technique employed is fluorescent nerve tract tracing using two fluorescent tracers implanted separately into each anterodorsal thalamic nucleus then followed retrogradely to the soma of the neurons in the lateral mammillary nucleus. Fluorescent photomicrography allowed us to document the single and double labeled cells of the lateral mammillary nucleus. The single labeled cells can be categorized into ipsilaterally projecting neurons and contralaterally projecting neurons. About half of all labeled cells were bilaterally projecting double-labeled, a third was ipsilaterally projecting single-labeled and the remainder were contralaterally projecting single labeled-cells. There were no labeled cells traced to the medial mamillary nucleus. The mammillary bodies play an important role in the limbic circuitry and a part of the so-called "Papez Circuit". The pathway by which the mammillary body projects to the other structures of the limbic system and the way it connects the limbic system to other parts of the brain like the tegmentum is not fully understood. This clarification of the connection between the lateral mammilary nucleus and the anterodorsal thalamic nucleus is but one of the contemplated pathways.  相似文献   
996.
997.
Two hundred and eight patients of low back pain were studied in the department of orthopaedic surgery, GSVM Medical College, Kanpur. The patients were put on intensive conservative treatment in the form of analgesics, hard bed rest, spinal extension exercises, traction and lumbosacral support. Thirty-two patients did not respond to this treatment and their symptoms were of more than 6 months duration and they were subjected to epidural injection of local anaesthetic agent, saline and corticosteroids. The failed 6 cases were investigated for consideration of surgery. The aim of this study is to develop standardised strategy for the treatment of low back pain. For the low back pain patients not responding to intensive conservative treatment, an idea has been put forward in the form of epidural medication prior to considering them to surgery to prevent unnecessary incidence of "failed back". A trial of epidural injection is suggested to avoid surgery.  相似文献   
998.
The ability of amniotic membrane, obtained with 3 h of delivery of 28 infants, to interconvert 3H-cortisol and 14-C-cortisone has been examined. The conversion of cortisone to cortisol increases as a function of gestational age, being first seen at 29.5 weeks and reaching values of 50--55% at term (n = 28, r = 0.615, P less than 0.01). Furthermore, a net gain of the active hormone (cortisol) resulting from the bidirectional interconversion of cortisol and cortisone ("C-11 activation index") appears at 31 weeks and reaches 40--50% by term (n = 28, r = 0.674, P less than .001). We speculate that this phenomenon could be an important source of active glucocorticoid for the fetus.  相似文献   
999.
In experiments on cats subject to study was the effect of histamine and nicotine used in different doses on the level of "key" metabolites of the carbohydrate metabolism and on the catecholamines balance in the wall of vessels of different functional purpose at the instant of the maximum, bioelectric and motor response to a vasomotor agent. It was shown that the vasodilation phase observed after introduction of the mediatory type drugs was attended by activation of the carbohydrate metabolism this proving the energy-dependence of the relaxation process. The presence of variously oriented and differently marked changes in the content of the carbohydrate metabolites in vessels vessels of diverse functional purpose made it possible to classify the vessels according to the type of metabolism, which coincides with their functional purpose.  相似文献   
1000.
This paper presents a methodology for the assessment of the remaining load carrying capacity of thin‐walled components under tension containing highly strength undermatched welds and edge cracks. The analysis is based on the strength mismatch option of the fracture module, part of the newly developed European fitness‐for‐service (FFS) procedure FITNET. The mismatch option of the FITNET fracture module allows weld features such as weld tensile properties and weld geometry to be taken into account in the fracture analysis of cracked welded components. The methodology described was verified for centre cracked Al‐alloy large tensile panels containing undermatched welds in Ref. [ 1 ] and hence the present work provides validation with experimental results of the single edge cracked (SEC) and double edge cracked (DEC) panels. The material used is an age‐hardening aluminium alloy 6013 in T6 temper condition used in welded airframe components. The welds in the form of butt joints were produced using the CO2 laser beam welding process. The results show that by using the FITNET FFS methodology with an appropriate selection of the input parameters, safe acceptable predictions of the maximum load carrying capacity of the welded panels can be obtained. It should also be noted that one of the main difficulties that engineers encounter when applying mismatch analysis for first time is its apparent complexity. A step‐by‐step analysis is proposed here in order to provide guidance for this kind of assessments.  相似文献   
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