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181.
MD Iafrati HJ Welch TF O'Donnell 《Canadian Metallurgical Quarterly》1997,25(6):995-1000; discussion 1000-1
PURPOSE: Early results of subfascial endoscopic perforator surgery (SEPS) were examined. Data on ulcer healing, complications, and costs are presented. METHODS: Data were prospectively collected for all patients who underwent SEPS at our institution. A concurrent control group was not available because primary open perforator ligation is no longer performed at our hospital. Preoperative assessment included duplex scanning (valve closure times and perforator mapping), plethysmography, and phlebography. Completeness of therapy was assessed with postoperative duplex mapping of perforating veins. Clinical status was monitored after surgery, and actual costs, including equipment, personnel, and facilities management, are reported. RESULTS: Eighteen procedures were performed in 15 patients (mean age, 52 years; range, 42 to 65 years). Two patients underwent bilateral SEPS, and one patient underwent a second procedure on the same leg. Active ulceration (class 6) was present in 14 of 18 limbs (78%), recently healed ulcers (class 5) in two of 18 (11%), and lipodermatosclerosis with edema (class 4) in two. Deep venous insufficiency was present in 14 of 18 (78%). The number of perforating veins ligated per leg ranged from 0 to 12 (mean, 4.3). Follow-up ranged from 3 to 64 weeks (mean, 22 weeks). Complete ulcer healing occurred in eight of 14 limbs (57%) at a mean of 14 weeks. Reduction in ulcer size was noted in four of 14 (29%), and two limbs were not improved. There were no new ulcers. Residual perforating veins were noted in four of 18 limbs. None of the limbs with residual perforating veins had complete healing of ulceration. Operating room costs were higher than those associated with limited-incision open perforator ligation ($2570 vs $1883). CONCLUSION: These preliminary data suggest that when used as part of a treatment plan to correct deep and superficial venous insufficiency SEPS results in a high rate of wound healing, with no recurrent ulceration in this series. Increased operating room costs associated with longer operations and greater disposable expenses will likely be overcome by shortened length of stay and diminished wound complications. These findings emphasize the importance of ligating all incompetent perforating veins, as ulcer healing was never achieved when residual perforating veins were found at follow-up. 相似文献
182.
Goats which have recovered from acute Anaplasma ovis infection remain seropositive, although infected erythrocytes cannot be detected by microscopic examination. Persistence of A. ovis 17 to 21 months following experimental infection was demonstrated by PCR detection of the msp-5 gene. Quantitative analysis of persistent rickettsemia over time showed that all levels were below the limit of microscopic detection and ranged from a low of 10(2) organisms/ml to peaks of 10(6) organisms/ml. Two patterns of persistent rickettsemia were observed: the first was characterized by cyclic fluctuations at 6- to 9-week intervals, similar to the pattern described for A. marginale-infected cattle, while in the second pattern, repetitive cycles did not occur and the rickettsemia levels were relatively constant. The msp-2 and msp-3 multigene families, which provide the genetic capacity for outer membrane protein antigenic variation during persistent A. marginale rickettsemia, were identified in the A. ovis genome by Southern blot analysis, and expression of an MSP-2 homologue was confirmed by using immunoblots. 相似文献
183.
Canine distemper virus DNA vaccination induces humoral and cellular immunity and protects against a lethal intracerebral challenge 总被引:1,自引:0,他引:1
N Sixt A Cardoso A Vallier J Fayolle R Buckland TF Wild 《Canadian Metallurgical Quarterly》1998,72(11):8472-8476
We have studied the immune responses to the two glycoproteins of the Morbillivirus canine distemper virus (CDV) after DNA vaccination of BALB/c mice. The plasmids coding for both CDV hemagglutinin (H) and fusion protein (F) induce high levels of antibodies which persist for more than 6 months. Intramuscular inoculation of the CDV DNA induces a predominantly immunoglobulin G2a (IgG2a) response (Th1 response), whereas gene gun immunization with CDV H evokes exclusively an IgG1 response (Th2 response). In contrast, the CDV F gene elicited a mixed, IgG1 and IgG2a response. Mice vaccinated (by gene gun) with either the CDV H or F DNA showed a class I-restricted cytotoxic lymphocyte response. Immunized mice challenged intracerebrally with a lethal dose of a neurovirulent strain of CDV were protected. However, approximately 30% of the mice vaccinated with the CDV F DNA became obese in the first 2 months following the challenge. This was not correlated with the serum antibody levels. 相似文献
184.
LH Gold HS Fox SJ Henriksen MJ Buchmeier MR Weed MA Taffe S Huitrón-Resendiz TF Horn FE Bloom 《Canadian Metallurgical Quarterly》1998,27(2-3):104-112
A model is proposed in which a neurovirulent, microglial-passaged, simian immunodeficiency virus (SIV) is used to produce central nervous system (CNS) pathology and behavioral deficits in rhesus monkeys reminiscent of those seen in humans infected with human immunodeficiency virus (HIV). The time course of disease progression was characterized by using functional measures of cognition and motor skill, as well as neurophysiologic monitoring. Concomitant assessment of immunological and virological parameters illustrated correspondence between impaired behavioral performance and viral pathogenesis. Convergent results were obtained from neuropathological findings indicative of significant CNS disease. In ongoing studies, this SIV model is being used to explore the behavioral sequelae of immunodeficiency virus infection, the viral and host factors leading to neurologic dysfunction, and to begin testing potential therapeutic agents. 相似文献
185.
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189.
CP Davis TF Hany S Wildermuth M Schmidt JF Debatin 《Canadian Metallurgical Quarterly》1997,17(5):1061-1077
Contrast material-enhanced three-dimensional (3D) magnetic resonance (MR) angiography is rapidly gaining acceptance as a versatile noninvasive alternative to conventional angiography. The technique has proved useful in the visualization and assessment of complex pathologic entities in the thoracic and abdominal aorta, renal arteries, pelvic arterial system, and pulmonary arteries. Several postprocessing techniques are available for reformation of the imaging data, including maximum intensity projection (MIP), surface rendering, and virtual intraluminal endoscopy (VIE). MIP and subvolume MIP reconstructions can be produced quickly and are useful for demonstration and archiving purposes. Because of its unique ability to display vessels without overlap, surface rendering is especially useful in depicting diseases that influence either the outer shape of the vessels or their topographic arrangement. VIE allows assessment of the inside of the vascular wall and is helpful in detecting wall-bound thrombus and evaluating the degree of stenosis. Most clinically relevant questions (eg, presence of pulmonary embolism, aortic aneurysm, renal artery stenosis) can be fully answered if analysis is based on MIP and thin multiplanar reformations of contrast-enhanced 3D MR angiograms. In some cases, the use of additional postprocessing techniques enhances diagnostic confidence. 相似文献
190.
TF Watson 《Canadian Metallurgical Quarterly》1997,11(4):433-441
PURPOSE: To analyze the results of a series of end-to-end urethroplasties performed in our service from 1968 to 1995 and of the factors contributing to failure. MATERIAL AND METHODS: 150 men (mean age 35.9 years) with urethral stricture disease underwent excision of the stricture and end-to-end anastomosis; in 95 it was the first attempt at repair while in 55 it was a secondary attempt. Eighty-two patients (54.6%) had a trauma-related stricture; of them, 56 followed a pelvic ring fracture with posterior urethra distraction defect, 24 (16%) had inflammatory strictures, 26 (17.3%) iatrogenic, 9 (6%) congenital, and 9 (6%) of unknown etiology; 81 (54%) were located in the bulbous urethra, 9 (6%) in the penoscrotal junction and 2 (1.3%) in the penile urethra. Ninety-one (60.6%) of the strictures or obliterative defects measured between 1 and 3 cm, 42 (28%) less than 1 cm and only 16 (10.6%) more than 3 cm. A perineal approach was used in 138 of the cases, while combined abdominoperineal route was necessary in 12; of these, 5 were children. The follow-up has ranged from 6 to 168 months (mean 44.4). The results were classified as good, fair (some re-stricturing, not needing treatment) and poor (recurrence). RESULTS: One hundred and twenty-six (84%) good outcomes, 10 (6.6%) fair, 14 (9.3%) poor. The factors influencing success or failure were: (1) primary or secondary character of the operation; (2) etiology; (3) length, and (4) location. Postoperative early complications consisted of 2 wound infections and 2 hematomas; as late complications, 1 chordee, 2 incontinence, 7 erectile dysfunction (in previously potent patients). The 14 patients considered as failures were operated again, all successfully; in 4 of them, a repeat excision and end-to-end anastomosis was performed, elevating the final success rate of the series to 93.3%. CONCLUSION: Excision and anastomotic repair represent the optimal mode of stricture repair for single lesions located from the penoscrotal junction to the membranous part of the urethra. 相似文献