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71.
OBJECTIVE: Peer review is an important part of the publication of scientific results. We analysed the peer review process of abstracts submitted to the European Association for the Study of the Liver (EASL) congress in Copenhagen in 1995. DESIGN: Comparative study. All abstracts were reviewed by all six members of the EASL scientific committee. Furthermore, each abstract was evaluated by three to six experts within 17 specific study fields, appointed by the scientific committee. All abstracts received a score on a scale from 1 to 5, one being the best. For each abstract the average was calculated for the scores of the committee members and the expert reviewers separately. MAIN OUTCOME MEASURE: Abstract score. RESULTS: There was a significant difference in the scores between the committee members, who scored 3.31 on average, and the expert reviewers, who scored 3.02 on average. Within most of the study fields the tendency was that the expert reviewers gave the highest scores. Moreover, there was a significant variation in the estimates among the individual reviewers as well as between the 2 groups of reviewers. Only 25% of the abstracts that received the best scores by the expert reviewers were classified in the same way by the committee members. The predictive value of a positive evaluation by the committee members was 0.6, the predictive value of a negative evaluation was 0.90. CONCLUSIONS: There was a considerable variation in the peer review process for abstracts submitted to the 1995 EASL congress depending on selection of reviewers. Various types of peer review strategies should be tested and evaluated to secure the highest possible scientific quality of published research results.  相似文献   
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Thermoelectric generators (TEGs) make use of the Seebeck effect in semiconductors for the direct conversion of heat to electrical energy. The possible use of a device consisting of numerous TEG modules for waste heat recovery from an internal combustion (IC) engine could considerably help worldwide efforts towards energy saving. However, commercially available TEGs operate at temperatures much lower than the actual operating temperature range in the exhaust pipe of an automobile, which could cause structural failure of the thermoelectric elements. Furthermore, continuous thermal cycling could lead to reduced efficiency and lifetime of the TEG. In this work we investigate the long-term performance and stability of a commercially available TEG under temperature and power cycling. The module was subjected to sequential hot-side heating (at 200°C) and cooling for long times (3000 h) in order to measure changes in the TEG’s performance. A reduction in Seebeck coefficient and an increase in resistivity were observed. Alternating-current (AC) impedance measurements and scanning electron microscope (SEM) observations were performed on the module, and results are presented and discussed.  相似文献   
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The synthesis of a peptide belonging to the VP3 capsid protein of Hepatitis A virus has been accomplished by the continuous flow Fmoc-polyamide solid phase method. The use of methoxytrimethylbenzenesulphonyl (Mtr) and pentamethylchromansulphonyl (Pmc) as arginine side-chain protecting groups in the presence of tryptophan without lateral protection or protected with t-Boc is discussed. The synthetic VP3 peptide has been administered to mice in different forms: (i) free, (ii) coupled to keyhole limpet hemocyanin, (iii) encapsulated in multilamellar (MLV) liposomes, and (iv) incorporated to a tetrameric branched lysine core. The immune response induced by these preparation is reported.  相似文献   
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In cooperation with the Chinese Academy of Preventive Medicine and Yunnan Province Provincial Office for AIDS Control and Prevention, we studied the current status of HIV infection intravenous drug users (IVDUs) and other high risk groups in Yunnan province of China. As of the end of 1995, 1,807 HIV cases were officially reported (Positive rate was 0.6%), of which 1,278 (77.9%) were IVDUs, and 24 were their spouses. The majority of cases were found among the Dai minority male farmers near Ruili which borders on Myammar, but HIV also appears to be spreading among the Han people. HIV antibody positive rates among commercial sex workers, pregnant women and blood donors were 0.2%, 0.07% and 0.04%, respectively. A system for surveillance of HIV has been developed, but preventive strategies to cope with HIV epidemic are not sufficient. As HIV/AIDS is now a global issue, (1) the integration and coordination of such preventive strategies in cooperation with community health workers, (2) general health education for condom use promotion and (3) care of psychological vulnerable person such as IVDUs, should be developed.  相似文献   
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To determine the influence of age on postoperative hypoxemia, we studied postoperative hypoxemia in 1152 patients, from infants to adults, ASA physical status I, undergoing elective plastic surgery. Subjects were divided into four groups on the basis of age: Group 1, infants aged 1 yr or less (n = 108); Group 2, children aged 1-3 yr (n = 240); Group 3, children aged 3-14 yr (n = 482); and Group 4, adults aged 14-58 yr (n = 322). Arterial oxygen saturation (Spo2) levels were recorded while patients were breathing room air in the postanesthesia recovery room shortly after arrival (0 min), and 5, 10, 15, 20, 30, 40, 50, 60, 120, and 180 min thereafter. Younger patients showed lower Spo2 levels and a higher incidence of hypoxemia during the early postoperative period. The incidences of hypoxemia (Spo2 = 86%-90%) and severe hypoxemia (Spo2 < or = 85%) in the recovery room were 30.6% and 16.7%, respectively, in Group 1, 20.0% and 10.0% in Group 2, 14.1% and 3.3% in Group 3, and 7.8% and 0.6% in Group 4. Hypoxemia occurred most commonly within 1 h after anesthesia, particularly during the first 40 min in infants and during the first 15 min in older children and adults. A significant correlation was found by linear regression analysis between low Spo2 levels on admission to the recovery room and children's age. Thereafter, Spo2 levels and the incidence of hypoxemia during the early postoperative period were related only to infants' recovery scores.  相似文献   
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The loss of spleen may lead to fatal bacterial infections. To prevent this, splenic autotransplantation has been performed in humans and experimental animals. However, there is still controversy about the protective function of this procedure. Since innervation plays an important role in splenic function, we investigated whether splenic regenerates are re-innervated, and whether this depends on the donor and host age. Splenic tissue (30 mg) was implanted into the greater omentum of either young (2 days) or old (12 months) rats, from either young or old syngeneic animals. After 3 months of regeneration, the weight of the regenerates was determined, PGP+ nerve fibers were revealed by immunohistology, and subdivided into nerve fibers of sympathetic (TH+, NPY+) or sensory (SP+, CGRP+) origin. In addition, proliferating (Ki-67 proliferation antigen+) and apoptotic cells (TUNEL technique+) were likewise investigated. No innervation of splenic regenerates was observed after implantation into old hosts, correlating with poorly developed splenic compartments. In contrast, almost normal re-innervation occurred in young hosts after implantation of both young and old splenic tissue. These regenerates showed well-developed splenic compartments and a normal number and tissue distribution of proliferating and apoptotic cells. However, after the implantation of young tissue, the final size of splenic regenerates was three times larger (140 +/- 30 vs. 40 +/- 10 mg). Thus, re-innervation of splenic implants is necessary for their subsequent development. It is determined by host age, whereas the final size of the splenic regenerates is regulated by donor age-dependent factors. This model is useful for studying both the process leading to initial innervation and the consequences of this innervation.  相似文献   
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