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991.
992.
OBJECTIVE: Cardiovascular events are the principal cause of medical morbidity in patients receiving ECT. To assess the risks of ECT for individuals with preexisting cardiovascular disease, the authors examined medical complications in older patients treated with ECT during a 1-year period. METHOD: A case-control design was used in a review of the charts of 80 consecutive patients who received ECT from August 1990 to August 1991. On the basis of accepted clinical criteria, patients over 50 years of age were divided into two groups: one at increased risk for cardiac complications (N = 26) and one at standard cardiac risk (N = 27). Outcome was measured with a scale designed to assess clinically relevant medical complications. RESULTS: The risk group was older and had received more medical consultations before ECT than the nonrisk group. Although patients in the risk group were more likely to develop minor complications during ECT, they did not differ significantly from the comparison group in the rate of major complications. No patients died or sustained permanent cardiac morbidity during ECT. CONCLUSIONS: In contrast to a similar study at the same site 15 years earlier, the current study found ECT to be relatively safe in an unselected study group of elderly patients with preexisting cardiac risk factors. The findings underscore the advances in ECT technique over the past 15 years and the importance of identifying and carefully managing patients with cardiac risk factors before and during ECT. 相似文献
993.
AD Weinberg B Celnik M Vainiene AC Buenafe AA Vandenbark H Offner 《Canadian Metallurgical Quarterly》1994,49(1-2):161-170
Vaccination or treatment of Lewis rats with TCR V beta 8 peptides can prevent or reverse the clinical signs of experimental autoimmune encephalomyelitis (EAE) which is mediated predominantly by V beta 8.2+ CD4+/CD45R lo T cells. However, rats protected or treated with V beta 8 peptides still developed histological lesions in the spinal cord (SC), even though they remained clinically well. We sought to discern phenotypic changes characteristic of these SC infiltrating lymphocytes. In particular, we focused on whether the immunoregulatory mechanism induced by TCR peptides caused a reduction of V beta 8.2+ T cells, or induced changes in CD45R lo or hi/CD4+ subpopulations that have been associated respectively with EAE induction or recovery. In the V beta 8 peptide vaccinated rats there was a dramatic decrease in the number of V beta 8.2+ T cells isolated from the SC early in disease. During the recovery phase, however, the number of V beta 8.2+ SC T cells was similar in protected and control groups; in contrast, there was striking reduction in the number and size of CD45R hi/CD4+ T cells in the protected animals. In rats treated with V beta 8.2 peptide, no changes were observed in the number of SC V beta 8.2+ T cells or expression of V beta 8.2 message, but similar to vaccinated rats, there was a marked decrease in the number of CD45R hi/CD4+ T cells. These data suggest that vaccination with TCR peptides prevented the initial influx of encephalitogenic V beta 8.2+ T cells into the central nervous system (CNS), whereas treatment appeared to inactivate V beta 8.2+ T cells already present in the CNS. In both cases, TCR peptide-induced inhibition of the encephalitogenic T cells apparently preempted the need for CD45R hi/CD4+ T cells that may normally be necessary to resolve the disease. 相似文献
994.
1. In this program management/community network model of occupational health services, the occupational health nurse is responsible for managing program development and implementation, with vendors providing the clinical services. 2. Occupational health nurses' primary areas of responsibility are occupational health, disability case management, ergonomics, and health promotion. 3. Successful management of program outcomes requires the occupational health nurse to continually assess employee/business needs, maintain communication with employees and management, and partner with the environmental, health, and safety team, other functional work groups, and vendors. 4. Effective management of contracts becomes critical to the process beginning with clear service requirements through the delivery of quality services. 相似文献
995.
JH Palma DR Almeida AC Carvalho JC Andrade E Buffolo 《Canadian Metallurgical Quarterly》1997,63(4):1081-1084
BACKGROUND: The surgical treatment of acute complicated type B aortic dissection continues to be a challenge and is still associated with high morbidity and mortality rates. METHODS: Seventy consecutive patients with an acute type B aortic dissection underwent an elephant trunk procedure through a median sternotomy during deep hypothermic circulatory arrest. An endoprosthesis that was 22 to 24 mm in diameter was inserted through an incision in the arch and held in place with only proximal sutures. RESULTS: The mean arrest time was 31.4 +/- 8.7 minutes, and it was possible to adequately position the endoluminal graft in every patient. The procedure was done in association with other procedures in 13 patients. There were six in-hospital deaths not related to the endoprosthesis, and four late deaths. Late reoperation was necessary in 6 patients to manage leakage at the proximal suture line. CONCLUSIONS: The insertion of an endoprosthesis through the arch for the management of a complicated acute type B dissection has several advantages over the conventional thoracotomy approach. The hospital mortality rate in this series of 70 patients was 20%, and the actuarial 5-year survival rate was 62.5%. We consider the elephant trunk procedure the treatment of choice in patients with type B acute dissections, regardless of whether the dissection is complicated or not. 相似文献
996.
An in vitro perifusion system for bovine hypothalamic tissue was used to determine if growth hormone-releasing hormone (GHRH) and somatostatin (SRIF) modulate each other's release, and whether SRIF mediates D1-agonist-induced suppression of GHRH in cattle. Up to three sagittal slices (600 microns) of bovine hypothalamus, immediately parallel++ to the midline, were cut in an oxygenated balanced salt solution at 4 degrees C, placed in 5 cc syringe barrels, and perifused at 37 degrees C with oxygenated minimum essential medium-alpha at a flow rate of 0.15 ml/min. Three experiments were conducted, and medium effluent was collected every 20 min before (two samples), during (one or three samples), and after (six samples) treatment. Areas under GHRH and SRIF response curves (AUC), adjusted by covariance for pretreatment values, were calculated from samples collected during the treatment/post-treatment period. Perifusion of SRIF at 10(-6) M and 10(-4) M decreased AUC for GHRH from 86.3 (control) to 65.4 and 59.5 +/- 6.3 ng.ml-1 min, but 10(-8) M SRIF was ineffective. Relative to controls, 10(-8).10(-6), and 10(-4) M GHRH increased release of SRIF 190, 675, and 1,135%, respectively. Activation of D1 receptors with 10(-6) M SKF 38393 increased AUC for SRIF from 12.5 ng.ml-1 min (control) to 484.9 ng.ml-1 min and decreased AUC for GHRH from 36.4 ng.ml-1 min (control) to 18.2 ng.ml-1 min. Blockade of SRIF action with a SRIF antagonist, cyclo-[7-aminoheptanoyl-phe-D-trp-lys-thr(bzl)], increased release of GHRH 1.9-fold. In addition, the SRIF antagonist blocked SKF 38393-induced suppression of GHRH. We concluded that GHRH and SRIF interact within the bovine hypothalamus/pituitary stalk to modulate the release of the other. Moreover, SRIF mediates the inhibitory effects of activation of D1 receptors on release of GHRH in cattle. 相似文献
997.
998.
KD Shelbourne RA Rubinstein CD VanMeter JR McCarroll AC Rettig 《Canadian Metallurgical Quarterly》1994,22(6):774-7; discussion 777-8
One hundred twenty-one patients were prospectively studied to determine whether the different remaining patellar tendon widths after central 10-mm bone-patellar tendon-bone graft harvest influenced the rate and level of quadriceps strength achieved during rehabilitation. Size of the patellar tendon width, measured at the same location in each patient, ranged from 24 to 35 mm. For this study, patients were grouped according to their remaining tendon size into small (14 to 17 mm; mean, 15.8), medium (18 to 20 mm; mean, 19.2), and large (21 to 25 mm; mean, 22.5) widths. Postoperatively, the patient's isokinetic quadriceps scores were determined at 6 weeks, 3 months, 6 months, and 1 year. At 6 weeks, the small- and medium-width tendon groups were significantly weaker than the large-width tendon group. At 3 months, only the small-width tendon group continued to be significantly weaker than the large-width tendon group. At and beyond 6 months, no statistically significant differences were seen between remaining patellar tendon width groups and their isokinetic quadriceps scores. A constant-sized autogenous patellar tendon graft may be harvested for anterior cruciate ligament reconstruction without compromising ultimate postoperative quadriceps strength recovery. 相似文献
999.
Radiosurgery, a bladeless brain surgery without opening skull, requires higher imaging accuracy as compared to microsurgery. Accordingly, we must refine the ways we use the MR scanner and interpret the obtained images. A well tuned and regularly calibrated MR scanner provides excellent images, which allow us to define detailed intracranial structures without distortion. This enables us to obtain a reliable imaging diagnosis despite the fact that pathologic diagnosis is not available in many radiosurgical patients. Due to its three-dimensional imaging and excellence in tissue and spatial contrast, MR is important in exploring new radiosurgical indications. Large arteriovenous malformations (AVM), dural AVM of cavernous sinus and trigeminal neuralgia are some of the successful examples. By using MR, longitudinal investigation of radiosurgical effects becomes feasible. For tumors, the longitudinal studies are important in optimization of dose selection. For AVM, MR is reliable in verification of radiosurgical result. The reliability is comparable to conventional x-ray angiography. Application of MR enhances the essence of noninvasiveness of radiosurgery. 相似文献
1000.
Boc-Tyr-Gly-Gly-Phe-Leu-Ch2Cl was synthesized by the conventional solution method. During the course of acid hydrolysis (6N HCl, 110 degrees C, 18h) of Boc-Phe-Leu-CH2Cl, side reaction occurred, resulting in low recovery of Phe residue on amino acid analysis. The inhibitory activity of the synthesized Boc-Tyr-Gly-Gly-Phe-Leu-CH2Cl against endopeptidase 22.19, an enzyme related to the metabolism of opioid peptides, was examined. 相似文献