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871.
Use of the vena cava to extend the right renal vein for cadaver transplantation is controversial. Right renal vein extension permits an easier anastomosis and possibly better positioning of the kidney, but may create a low flow or turbulent state. We studied whether use of a vein extension had an impact on outcome. Between January 1986 and April 1993, 305 cadaver transplant recipients received a right kidney. Of these, 76 received a graft with vein extension. None of the 76 experienced technical vascular complications versus 5 of the 229 (2.2%) without vein extension. There was no difference in 1- and 2-year graft survival for those with versus without extension. We conclude that there is no increased risk with use of the vena cava extension and recommend that the donor team routinely provide the right kidney with the vena cava attached. This allows the recipient team to determine whether an extension is appropriate for the particular recipient.  相似文献   
872.
The distribution of the zot gene that encodes the zonula occludens toxin, a newly described toxin of Vibrio cholerae, among clinical, environmental and food isolates of V. cholerae 01 and non-01 was investigated. Both the zot gene and the ctx gene that encode cholera toxin were found in 247 of 257 clinical strains and 62 of 415 environmental or food isolates of V. cholerae 01. The zot gene, but not the ctx gene was found in 37 strains (one clinical strain and 36 environmental or food isolates). In addition, two of 31 clinical strains and six of 98 environmental or food isolates of V. cholerae' non-01 possessed both the zot gene and the ctx gene. These results demonstrated the predominantly concurrent occurrence of the zot gene and ctx genes among strains of V. cholerae 01 which suggests a possible synergistic role of ZOT in the causation of acute dehydrating diarrhea produced by V. cholerae 01.  相似文献   
873.
874.
The prevalence of psychiatric disorders in a large residential population (N = 1,273) of individuals with mental retardation was examined. We found that the point prevalence rate for dual diagnoses based on DSM-III-R criteria was 15.55% (n = 198). Rates for specific psychiatric disorders were also provided by level of retardation and sex. Results were compared to similar epidemiological studies and discussed in light of factors hypothesized to affect diagnosis of psychiatric disorders among individuals with mental retardation.  相似文献   
875.
Degenerate oligonucleotides encoding conserved regions of the Rad52 protein of S. cerevisiae and its homologue, the Rad22 protein of S. pombe, were used to clone a chicken RAD52 counterpart by the polymerase chain reaction. Sequence comparison of the chicken and yeast proteins reveals a strongly conserved region between positions 40 and 178 of the chicken Rad52 sequence indicating that this part of the protein is under strong evolutionary pressure. The first 39 amino acids and the 3' end of the chicken Rad52 homologue does not share significant similarity with the yeast proteins. High abundance of the mRNA in testis makes it likely that the chicken Rad52 protein plays a role in meiotic recombination.  相似文献   
876.
877.
BACKGROUND: Differences in the management of acute myocardial infarction have been reported among countries, but few studies have investigated this issue in regions of the United States. METHODS: We compared the management of acute myocardial infarction among census regions across the United States, using data from the first Global Utilization of Streptokinase and Tissue Plasminogen Activator for Occluded Coronary Arteries trial (GUSTO-1) comprising 21,772 patients, and from the American Hospital Association. RESULTS: We found substantial regional variation in the management of acute myocardial infarction in the United States. Beta-blockers (prescribed for a range of 55 to 81 percent of patients in the various regions), nitrates (prescribed for 61 to 77 percent), and angiotensin-converting-enzyme inhibitors (prescribed for 18 to 23 percent) were used most often in New England, whereas calcium-channel blockers (31 to 42 percent) and lidocaine (14 to 43 percent) were used least often there. Similarly, the proportion of patients undergoing various cardiac procedures differed among regions (range for angiography, 52 to 81 percent of patients; angioplasty, 22 to 35 percent; and coronary-artery bypass surgery, 9 to 17 percent) and was lowest in New England. The regional use of cardiac procedures was closely related to their availability, except in New England. After the analysis was adjusted for clinical and hospital variables, patients in New England were found to be less likely to undergo angiography than patients in the other regions (odds ratio, 0.37; 95 percent confidence interval, 0.32 to 0.42). There was no apparent relation between the use of cardiac procedures and rates of recurrent infarction or death at 30 days or 1 year. CONCLUSIONS: There is substantial regional variation in the use of cardiac medications and procedures to manage acute myocardial infarction in the United States. The use and availability of cardiac procedures are closely related. The management of acute myocardial infarction in New England is atypical in that the relatively limited availability of cardiac procedures does not account for their relatively low use in that region.  相似文献   
878.
Synthesis of a series of thienylethanolamines having varying substituents on the thiophene ring and on the nitrogen atom is described using the general procedure reported earlier. In the determination of their pharmacological profile, some of the derivatives showed marked antihypertensive activity in the spontaneously hypertensive rat model. Tests are also reported which demonstrated that some of these derivatives antagonized alpha- and/or beta-adrenoreceptor activities. The ability of this class of compounds to inhibit catecholamine-induced release of free fatty acids by adipose tissue was demonstrated. Structure-activity relationships in different tests were also determined.  相似文献   
879.
880.
The kinetic parameters (K, R00, R12, R21 and Ree) of the simple carrier model are analysed as a function of applied voltage for various cases of charged substrates and carriers. If certain parameters are invariant with voltage, strong conclusions can be made as to the charge on the free carrier. In one particular case (where the parameter R00 is invariant while R12 and R21 display a non-linear dependence on the exponential of the voltage) it may be possible to identify the isomerisation of the carrier-substrate complex.  相似文献   
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