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A retrospective study was conducted to evaluate the impact of laparoscopic surgery on activity in general and digestive surgery. From May 1990 to December 1994, 2256 laparoscopic procedures were performed for cholecystectomy (36%), appendicectomy (20.4%) or inguinal hernia (19.8%). 23.2% of all procedures performed in 1994 were done laparoscopically. The use of laparoscopy did not, in our experience, added any new indications from 1988 to 1994. The conversion rate was 8.15%. 24% of the conversion cases could not be predicted. Mortality was 0.18% and 1.19% of the patients had to undergo a second operation due to complications of laparsocopic surgery. The impact of laparoscopic procedures, 7 years after the first laparoscopic cholecystectomy has been great. The results of this surgical technique must be evaluated to determine its medical and economic impact.  相似文献   
2.
OBJECTIVE: To compile, for the first time, serial ultrasonographic findings during the first trimester of pregnancy in women with a history of primary recurrent spontaneous abortion so as to define the dynamics of early normal and abnormal gestations in this category of gravidas. STUDY DESIGN: Transvaginal ultrasonograms were obtained weekly from 5 to 12 weeks' gestational age in 40 women, 10 each of four groups: recurrent spontaneous aborters and primiparas (controls), with both successful and failed gestations. RESULTS: Embryonic heart motion was detected in 40-50% of successful pregnancies during the fifth week of gestation and in the balance by the sixth week, while heart motion was detected in no more than 50% of pregnancies that later failed. Of the failed pregnancies, all were evident by the eighth week of gestation, including those with previously documented viability. The gestational sac size and crown-rump length were smaller than expected in both failed groups, with the sac size difference evident as early as week 5 and the crown-rump length difference apparent by week 7. CONCLUSION: Appropriate timing of the initial ultrasonogram in recurrent aborters (i.e., 8 weeks' gestational age) can identify, by means of heart motion and gestational sac features, all pregnancies that will ultimately fail.  相似文献   
3.
Investigated the role of the vagus in the lateral hypothalamic (LH) syndrome to body weight loss in 80 male Sprague-Dawley albino rats. Ss were divided into 4 groups: (a) Ss with bilateral LH lesions that were subsequently given a bilateral subdiaphragmatic vagotomy, (b) LH Ss that received a control vagotomy operation, (c) nonlesion Ss that were given a subdiaphragmatic vagotomy, and (d) nonlesion Ss that received a control vagotomy operation. Both LH lesions and vagotomy reduced body weight levels, though the effects differed in terms of the length of time required to reach initial maximal loss, the time required to reach chronic levels of maintenance, and the severity of body weight reduction. Fasting gastric acid secretion was lowered by LH lesions, and the extent of this reduction was positively correlated with the reduction in body weight. Gastric contents after a 24-hr fast were greater in vagotomized than in nonvagotomized Ss. These data are discussed in relation to the role of the vagus in maintaining body weight levels and in relation to the changes in gastric functioning after LH lesions and vagotomy. (42 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
4.
Our objective was to evaluate the hypothesis that measurements of caffeine, nutrients, and indicator bacteria can distinguish human versus non-human sources of surface water contamination in contrasting environments. A second objective was to determine if natural sources of caffeine were significant in unpopulated areas. Caffeine was measured in an isolated wetland, and a native plant source was identified. In two rural watersheds in southwest Georgia (U.S.), caffeine was detected in tributary creeks immediately below wastewater discharge sites and within towns. However, caffeine was not found in river main streams. Thus, although natural caffeine sources exist, background levels in stream drainage networks of these rural watersheds remained below detection. The presence of caffeine and elevated nitrate in streams was associated with anthropogenic inputs and population centers, whereas bacterial indicators did not correlate to these chemical indicators and appeared to have non-human sources. In contrast, caffeine in an urban coastal lagoon was generally linked to fecal coliform abundance. We observed sporadic relationships between caffeine and other water quality indicators, possibly due to differential rates of degradation. Creeks and bayous flowing into the lagoon contained the greatest caffeine concentrations and highest amounts of bacteria, nitrate, and radon, which is an indicator of groundwater discharge.  相似文献   
5.
RATIONALE AND OBJECTIVES: We evaluated magnetic resonance (MR) contrast enhancement of tumor tissue following injection of the macromolecular conjugate, gadopentetate dimeglumine-polylysine. METHODS: T1-weighted MR imaging scans were performed on female Fisher-344 rats with subcutaneously implanted mammary adenocarcinoma tumors. Following the baseline scan, gadopentetate dimeglumine-polylysine or gadopentetate dimeglumine was injected at a dose of 0.1 mmol gadolinium per kilogram. RESULTS: Gadopentetate dimeglumine-polylysine injection resulted in a maximum enhancement of tumor contrast of 310 +/- 60% (n = 7). Tumor tissue remained enhanced and well defined for several days after gadopentetate dimeglumine-polylysine injection. Gadopentetate dimeglumine injection at the same dose resulted in a 70 +/- 25% (n = 4) maximal tumor enhancement and a corresponding 25 +/- 4% muscle enhancement. CONCLUSION: Gadopentetate dimeglumine-polylysine provides higher, more sustained tumor contrast than does gadopentetate dimeglumine for the same dosage of gadolinium.  相似文献   
6.
Theories and research studies related to the effects of financial compensation on employee motivation are reviewed and critically evaluated. Such theories are based primarily on limited studies conducted on subhuman species; no deductions from these theories have been adequately tested in industry. Most compensation practices in industry are based on impressionistic evidence characterized by anecdotal accounts and data gathered by means of self-report questionnaires. Studies of the effects of money on employee behavior need to be conducted in laboratory or in tightly controlled field settings. A commendable start in this direction has been made, but more empirical tests of the bases of current compensation practices are needed. Such research should lead eventually to a sound theory of money and employee motivation from which more effective and more behaviorally relevant compensation practices may be derived. (2 p. ref.) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
7.
Solid-phase extraction (SPE) was tested for the isolation of dissolved lignin from diverse natural waters (fresh, estuarine, and marine) in preparation for CuO oxidation. Capillary GC coupled to selected-ion monitoring mass spectrometry (SIM-MS) of CuO oxidation products provides the high sensitivity and precision required for the identification and quantification of trace levels of lignin in seawater. The low blanks and quick cleanup of C18 cartridges support SPE for processing such samples. Comparison of SPE with other isolation procedures (direct dry-down and ultrafiltration) has shown that this method quantitatively recovers dissolved lignin and preserves its compositional parameters. The concentration and nature of dissolved organic matter appear to be primary factors that constrain the amount of water that should be processed to obtain quantitative and reproducible recoveries of dissolved lignin using SPE. Highest recoveries of dissolved lignin were obtained at low pH (1.5-4.0) with substantial decreases at pH > 4. Extraction efficiencies were independent of flow rate within a range of five to fifteen bed volumes per minute (50-150 mL min(-1)), and both refrigeration and freezing were appropriate long-term storage methods for processed cartridges prior to elution of retained dissolved lignin.  相似文献   
8.
Schoolteachers, nurses and doctors in primary health care in Stovner district, Oslo, have developed a new programme of sexual education for teenagers 14-16 years of age. The aim of the programme is to increase the knowledge about sexually transmitted diseases, reproduction and prevention of pregnancy and to open up for discussions within the classes about love, ethics, sexual abuse and sexual pressure. To evaluate the programme, pupils in the 9th grade in 1991 and 1993 (about 16 years old) answered a self-administered questionnaire. The answers showed an increase in knowledge about sexually transmitted diseases and reproduction, and a reduction in the percent of pupils who had sexual intercourse. The result should be cautiously interpreted, since changes in sexual knowledge and practices over time may have been caused by factors other than the intervention.  相似文献   
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