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991.
A 7- to 9-month protocol of prophylactic transfusion was used to treat 33 joints in 19 children with severe hemophilia (< 1 U/dL Factors VIII or IX) and hypertrophic synovitis. The overall rate of hemarthrosis was reduced, but only 36% (12 of 33 joints) achieved a good result (defined as 0-0.5 bleeding episodes per month and decreased synovial hypertrophy 1 year after completing treatment). Age and severity of arthropathy at initiation of treatment did not affect the result. The degree of synovial hypertrophy and involvement of the knee joint showed an adverse trend, but these factors did not achieve statistical significance. The number of episodes of breakthrough bleeding during the first 6 weeks of therapy was significantly associated with a poor result. Based on the results of this study, a trial of transfusion therapy is recommended for recurrent hemarthroses and synovitis in patients with hemophilia, but the duration of thrice weekly treatment has been increased and the duration of prophylaxis has been reduced in selected cases. 相似文献
992.
This study explored perspective taking in social phobics' images of past anxiety-provoking social situations and non-social situations. For images of social situations, social phobics were significantly more likely than non-patient controls to take an observer perspective, viewing themselves as if from an external point of view. In contrast, social phobics and controls did not differ in the perspective taken in images of non-social situations, which were generally viewed from a field perspective (seeing the situation as if looking out through their own eyes). The clinical significance of these findings is briefly discussed. 相似文献
993.
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995.
The Rhs elements are complex genetic composites widely spread among Escherichia coli isolates. One of their components, a 3.7-kb, GC-rich core, maintains a single open reading frame that extends the full length of the core and then 400 to 600 bp beyond into an AT-rich region. Whereas Rhs cores are homologous, core extensions from different elements are dissimilar. Two new Rhs elements from strains of the ECOR reference collection have been characterized. RhsG (from strain ECOR-11) maps to min 5.3, and RhsH (from strain ECOR-45) maps to min 32.8, where it lies in tandem with RhsE. Comparison of strain K-12 to ECOR-11 indicates that RhsG was once present in but has been largely deleted from an ancestor of K-12. Phylogenetic analysis shows that the cores from eight known elements fall into three subfamilies, RhsA-B-C-F, RhsD-E, and RhsG-H. Cores from different subfamilies diverge 22 to 29%. Analysis of substitutions that distinguish between subfamilies shows that the origin of the ancestral core as well as the process of subfamily separation occurred in a GC-rich background. Furthermore, each subfamily independently passed from the GC-rich background to a less GC-rich background such as E. coli. A new example of core-extension shuffling provides the first example of exchange between cores of different subfamilies. A novel component of RhsE and RhsG, vgr, encodes a large protein distinguished by 18 to 19 repetitions of a Val-Gly dipeptide occurring with a eight-residue periodicity. 相似文献
996.
CE Kawcak DD Frisbie GW Trotter CW McIlwraith SM Gillette BE Powers RM Walton 《Canadian Metallurgical Quarterly》1997,58(10):1132-1140
OBJECTIVE: To evaluate the effects of arthroscopic surgery, osteochondral fragmentation, and treatment with IV administered hyaluronate on histologic, histochemical, and biochemical measurements within the carpal joints of horses. ANIMALS: 12 clinically normal horses, 2 to 7 years of age. PROCEDURE: Horses had an osteochondral fragment created at the distal aspect of the radiocarpal bone of 1 randomly chosen middle carpal joint to simulate osteochondral fragmentation. Horses were treated with 40 mg of hyaluronate or saline solution (placebo) intravenously once a week for 3 consecutive weeks (days 13, 20, and 27 after surgery). Treadmill exercise proceeded 5 days per week beginning 15 days, and ending 72 days, after surgery. Clinical evaluations were performed at the beginning and end of the study. Synovial fluid samples were obtained aseptically from both middle carpal joints on days 0, 13, 20, 27, 34, and 72 after surgery, and total protein, inflammatory cell, hyaluronate, glycosaminoglycan, and prostaglandin E2 concentrations were measured in each sample. All horses were euthanatized on day 72. Synovial membrane and articular cartilage were obtained for histologic evaluation. Articular cartilage samples were also obtained aseptically for determining glycosaminoglycan content and chondrocyte synthetic rate for glycosaminoglycans. RESULTS: Horses treated with hyaluronate intravenously had lower lameness scores (were less lame), significantly better synovial membrane histologic scores, and significantly lower concentrations of total protein and prostaglandin E2 within synovial fluid 72 days after surgery, compared with placebo-treated horses. Treatment with intravenously administered hyaluronate had no significant effects on glycosaminoglycan content, synthetic rate or morphologic scoring in articular cartilage, or other synovial fluid measurements. CONCLUSION: Intravenously administered hyaluronate appears to alleviate signs of lameness by interacting with synoviocytes, and by decreasing production and release of inflammatory mediators. 相似文献
997.
Y Kakuta LG Pedersen CW Carter M Negishi LC Pedersen 《Canadian Metallurgical Quarterly》1997,4(11):904-908
OBJECTIVE: To describe a coccidioidomycosis outbreak in Ventura County following the January 1994 earthquake, centered in Northridge, Calif, and to identify factors that increased the risk for acquiring acute coccidioidomycosis infection. DESIGN: Epidemic investigation, population-based skin test survey, and case-control study. SETTING: Ventura County, California. RESULTS: In Ventura County, between January 24 and March 15, 1994, 203 outbreak-associated coccidioidomycosis cases, including 3 fatalities, were identified (attack rate [AR], 30 cases per 100,000 population). The majority of cases (56%) and the highest AR (114 per 100,000 population) occurred in the town of Simi Valley, a community located at the base of a mountain range that experienced numerous landslides associated with the earthquake. Disease onset for cases peaked 2 weeks after the earthquake. The AR was 2.8 times greater for persons 40 years of age and older than for younger persons (relative risk, 2.8; 95% confidence interval [CI], 2.1-3.7; P<.001). Environmental data indicated that large dust clouds, generated by landslides following the earthquake and strong aftershocks in the Santa Susana Mountains north of Simi Valley, were dispersed into nearby valleys by northeast winds. Simi Valley case-control study data indicated that physically being in a dust cloud (odds ratio, 3.0; 95% CI, 1.6-5.4; P<.001) and time spent in a dust cloud (P<.001) significantly increased the risk for being diagnosed with acute coccidioidomycosis. CONCLUSIONS: Both the location and timing of cases strongly suggest that the coccidioidomycosis outbreak in Ventura County was caused when arthrospores were spread in dust clouds generated by the earthquake. This is the first report of a coccidioidomycosis outbreak following an earthquake. Public and physician awareness, especially in endemic areas following similar dust cloud-generating events, may result in prevention and early recognition of acute coccidioidomycosis. 相似文献
998.
HB Faust R Gonin TY Chuang CW Lewis CA Melfi ER Farmer 《Canadian Metallurgical Quarterly》1997,133(11):1443-1448
OBJECTIVES: To describe a new severity of illness index for inflammatory skin disease called the Dermatology Index of Disease Severity (DIDS), and to show its preliminary use and reliability in staging disease in patients with psoriasis and dermatitis. DESIGN: Interobserver rating study using the DIDS with as many as 10 observers independently rating the same patient at a single point in time. SETTING: Ambulatory care clinics at an academic medical center with patients from various socioeconomic backgrounds. PATIENTS: Thirty-four patients with psoriasis and 15 patients with dermatitis were included in the study. MAIN OUTCOME MEASURES: The severity of illness for each patient was rated as 1 of 5 stages: 0, no evidence of clinical disease; I, limited disease; II, mild disease; III, moderate disease; and IV, severe disease. The degree of interobserver concordance was measured by the Cohen kappa statistic. RESULTS: All 5 stages were represented in the study of patients with psoriasis. The overall kappa statistic was 0.76, which is defined as substantial interobserver concordance. The use of the instrument in dermatitis showed good consensus in staging, where the kappa statistic was 0.41. CONCLUSION: We introduce an easy and efficient instrument for staging the severity of illness in inflammatory cutaneous diseases. The reliability of the DIDS is demonstrated in patients with psoriasis and in patients with dermatitis. 相似文献
999.
JM Yang TC Yuen CW Chang JS Jin MH Yen JW Chern 《Canadian Metallurgical Quarterly》1997,30(2):229-234
We evaluated the effect of sulindac sulfide (SS), which reduces cell number and induces apoptosis in cultured colon cancer cells (CCCs), on expression of the proliferation markers PCNA and Ki-67 in HT-29 and HCT-15 CCCs; only the former express cyclooxygenases. DNA content and PCNA/Ki-67 expression were analyzed by bivariate flow cytometry. SS inhibited cell proliferation, determined by the reduced expression of PCNA and Ki-67, roughly by half at 72 h, and induced apoptosis (accounting for about two-thirds and one-third of the reduction in cell number, respectively). A similar effect of SS occurred in HT-29 and HCT-15 CCCs, and also in non-colonic cells, indicating that this rather general effect of SS on cultured cells is not dependent on inhibition of prostaglandin synthesis. 相似文献
1000.
Segmentation (tissue classification) of the medical images obtained from Magnetic resonance (MR) images is a primary step in most applications of computer vision to medical image analysis. This paper describes a penalized fuzzy competitive learning network designed to segment multispectral MR spin echo images. The proposed approach is a new unsupervised and winner-takes-all scheme based on a neural network using the penalized fuzzy clustering technique. Its implementation consists of the combination of a competitive learning network and penalized fuzzy clustering methods in order to make parallel implementation feasible. The penalized fuzzy competitive learning network could provide an acceptable result for medical image segmentation in parallel processing using the hardware implementation. The experimental results show that a promising solution can be obtained using the penalized fuzzy competitive learning neural network based on least squares criteria. 相似文献