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The enzymatic activity of protein kinase C (PKC) was measured in the cytosol and particulate fraction of parabrachial nucleus, the presumed site of conditioned taste aversion (CTA) engrams. At various time intervals after acquisition of the task (pairing saccharin consumption with subsequent LiCl poisoning) the nucleus was dissected from the frozen coronal sections. An increase (+40%) in the cytosol PKC activity was found 48 h after that pairing in comparison with controls (saline injection instead of LiCl). Particulate enzyme activity virtual did not change (-5%). Thus the total PKC activity increased significantly (21%). Qualitatively similar but less markedly expressed PKC shifts (+18% in cytosol) ere found 24 h following CTA. Twelve hours and 5 days after CTA acquisition the activity and distribution of PKC was similar to that seen in normal rats. The control experiments revealed that 6 h after LiCl injection alone (without previous saccharin consumption) translocation of PKC from the cytosol to the membrane fraction (found previously 1 h after LiCl injection alone) still persisted but did not differ from that found 6 h after its pairing with saccharin drinking (CTA). It is concluded that acquisition of conditioned taste aversion may be followed by synthesis of PKC rather than by its translocation or downregulation.  相似文献   
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Five studies tested the hypotheses that there are individual differences in the frequency of automatic thoughts involving perfectionism and that these thoughts are associated with psychological distress. Research with the Perfectionism Cognitions Inventory (PCI) established that this new measure has adequate psychometric properties, and high PCI scorers tend to spontaneously report perfectionistic thoughts in naturalistic situations. Additional research confirmed that frequent perfectionism thoughts account for unique variance in distress, over and above variance predicted by standard measures of negative automatic thoughts and trait perfectionism measures. Overall, the findings support the view that personality traits involved in depression and anxiety have a cognitive component involving ruminative thoughts and that activation of this cognitive personality component contributes to distress.  相似文献   
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The goals of this study were to (1) determine the effects of repeated inhalation of relatively insoluble nickel oxide (NiO) and highly soluble nickel sulfate hexahydrate (NiSO4.6H2O) on lung particle clearance, (2) investigate the effects of repeated inhalation of NiO or NiSO4 on the pulmonary clearance of subsequently inhaled 85Sr-labeled microspheres, (3) correlate the observed effects on clearance with accumulated Ni lung burden and associated pathological changes in the lung, and (4) compare responses in F344 rats and B6C3F1 mice. Male F344/N rats and B6C3F1 mice were exposed whole-body to either NiO or NiSO4.6H2O 6 hr/day, 5 days/week for up to 6 months. NiO exposure concentrations were 0, 0.62, and 2.5 mg NiO/m3 for rats and 0, 1.25, and 5.0 mg NiO/m3 for mice. NiSO4.6H2O exposure concentrations were 0, 0.12, and 0.5 mg NiSO4.6H2O/m3 for rats and 0, 0.25, and 1.0 mg NiSO4.6H2O/m3 for mice. After 2 and 6 months of whole-body exposure, groups of rats and mice were acutely exposed nose-only to 63NiO (NiO-exposed animals only), 63NiSO4.6H2O (NiSO4.6H2O-exposed animals only), or to 85Sr-labeled polystyrene latex (PSL) microspheres (both NiO- and NiSO4.6H2O-exposed animals) to evaluate lung clearance. In addition, groups of rats and mice were euthanized after 2 and 6 months of exposure and at 2 and 4 months after the whole-body exposures were completed to evaluate histopathological changes in the left lung and to quantitate Ni in the right lung. Repeated inhalation of NiO results in accumulation of Ni in lungs of both rats and mice, but to a greater extent in lungs of rats. During the 4 months after the end of the whole-body exposures, some clearance of the accumulated Ni burden occurred from the lungs of rats and mice exposed to the lower, but not the higher NiO exposure concentrations. Clearance of acutely inhaled 63NiO was also impaired in both rats and mice, with the extent of impairment related to both exposure concentration and duration. However, the clearance of acutely inhaled 85Sr PSL microspheres was not impaired. The repeated inhalation of NiO resulted in alveolar macrophage (AM) hyperplasia with accumulation of NiO particles in both rats and mice, chronic alveolitis in rats, and interstitial pneumonia in mice. These lesions persisted throughout the 4-month recovery period after the NiO whole-body exposures were terminated. In contrast, repeated inhalation of NiSO4.6H2O did not result in accumulation of Ni in lungs of either rats or mice and did not affect the clearance of 63NiSO4.6H2O inhaled after either 2 or 6 months of NiSO4.6H2O exposure. Clearance of the 85Sr-labeled microspheres was significantly impaired only in rats exposed to the microspheres after 2 months of exposure to NiSO4.6H2O. Histopathological changes in rats were qualitatively similar to those seen in NiO-exposed rats. Only minimal histopathological changes were observed in NiSO4.6H2O-exposed mice. These results suggest that repeated inhalation of NiO at levels resulting in AM hyperplasia and alveolitis may impair clearance of subsequently inhaled NiO. The potential effects of repeated inhalation of soluble NiSO4.6H2O on the clearance of subsequently inhaled poorly soluble particles are less clear.  相似文献   
105.
Cardiopulmonary bypass, temporary cardiac arrest, and exsanguination have facilitated the surgical resection of renal tumors with intracaval thrombi that extend above the hepatic veins or into the atrium. The bloodless field provided by this approach enables the surgeon to utilize a flexible cystoscope to ensure that the caval thrombus has been removed entirely from the hepatic veins.  相似文献   
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The authors present a case of foreign body retention, following car accident, localized on superior medial corner of the right orbit. The traumatic impact, involving endo-orbital structures, owing to the peculiar direction of the foreign body, caused a fracture in the anterior cranial base and laceration of the dura madre. As the anatomical structures involved did not concern only the MaxilloFacial district, the choice of the protocol to be applied to the patient was taken in accordance with the neurosurgical équipe. An intra cranial surgical approach has allowed to remove, by retrograding the foreign body on its trajectory path, in order not to injure further the already damaged structures involved. Then the tissues have been reconstructed; in particular, the anterior cranial base was restored through the use of pericranial strip. This technique is the elective surgical treatment in lesions of such small entity, as it is able to grant a solid support to the overhanging cerebral parenchyma. Besides, this reconstruction technique provides a complete protecting isolation of the ocular globe from compressive and pulsative phenomena, due to the neurocranial adjacent structures. With this technique, after a 8 month's follow-up. The patient has obtained optimum functional and aesthetic results.  相似文献   
110.
Renal disease is a disease closely associated with aging. Although kidney disease can occur at any age, the prevalence and severity of renal disease is far more prominent in the elderly. As the geriatric population continues to grow, nurses can anticipate treating significant numbers of elderly people with renal disease. Research suggests that with early dietary intervention the progression of renal disease can be altered. Therefore, knowledge of the characteristics and goals of diet therapy are necessary to provide effective client education and promote compliance.  相似文献   
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