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661.
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The paper aims at describing easy steps: asepsis and hygiene to prevent nosocomial infections within surgery unit in Hospitals with limited budget. Essential and compulsory they are: cleansing of the surgery unit before any disinfection, behaviour of the staff in relation to aerobic contamination, maintenance of equipment, prophylaxis applied to patients antibio-prophylaxis is also mentioned complementary to that steps. Possible strategies of fight and control are mentioned, including awareness and full participation of all.  相似文献   
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665.
Results of 1.55-μm transmission experiments at 140, 280, and 565 Mb/s involving conventional and dispersion-shifted single-mode fibers along the Fabry-Perot laser diode (FP-LD) and distributed-feedback laser diode (DFB-LD) optical sources are discussed. The results show which combination of optical fiber and optical source best meet the requirement of long repeater spacing for each bit rate. The results indicate that to achieve repeater spacing more than 100 km with dispersion-shifted fibers and FP-LD optical sources will impose strict requirements on both the optical fibers and the optical sources even at 280 Mb/s. Alternatively, systems using DFB-LD optical sources will not degrade the transmission performances and will considerably loosen requirements on the fibers and optical sources. A combination of dispersion-shifted fibers and DFB-LD optical sources can further loosen the requirements on the fibers and optical sources in 560-Mb/s systems  相似文献   
666.
The antinociceptive effect of L-arginine in streptozotocin-induced diabetic mice was examined. Although s.c. administration of L-arginine produced a dose-dependent inhibition of the tail-flick response in both non-diabetic and diabetic mice, the antinociceptive response was greater in diabetic mice than in non-diabetic mice. The antinociceptive effects of L-arginine in both diabetic and non-diabetic mice were significantly antagonized by s.c. administration of naltrindole, a selective delta-opioid receptor antagonist. However, neither beta-funaltrexamine, a selective mu-opioid receptor antagonist, nor nor-binaltorphimin ++, a selective kappa-opioid receptor antagonist, significantly affected the antinociceptive effect of L-arginine in diabetic and non-diabetic mice. These results suggest that L-arginine produces a marked antinociceptive effect in diabetic mice through the activation of delta-opioid receptors.  相似文献   
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The morphologies and tensile properties of an elastomer-modified epoxy (EME)/polycarbonate (PC) binary system and an EME/diglycidyl ether of bisphenol A (DGEBA)/PC ternary system were examined. In the EME system, a continuous elastomer-rich phase formed, while in the EME/DGEBA systems (unblended with PC), a continuous epoxy-rich phase formed. In both of these systems, two-phase structures were observed. In contrast, a microdispersed structure was observed when the PC was blended with either the EME or with the EME/DGEBA systems. It is suggested that blending of the epoxy with PC caused an increased solubility of the former into the elastomer phase. The tensile strength and tensile elongation of both the EME and EME/DGEBA systems were improved by blending with PC. In the EME/PC blend, the tensile elongation reached its maximum value (60%) at a PC content of approximately 10 p.h.r. (parts per hundred resin by weight), with this maximum being approximately one and a half times higher than that of the unblended EME. Tensile strength was also clearly increased by blending with small amounts of PC, but soon reached a steady value. In the EME/DGEBA/PC blends, the tensile properties were dependent on the weight ratio of EME to DGEBA. In the absence of PC, as this ratio increased, the tensile elongation also increased, while at the same time the tensile strength decreased. The tensile properties were also improved in this system, by blending with PC. From the results obtained, it was clear that the improvement in tensile properties was closely related to the changes in morphology. Therefore, blending of the PC induced a microdispersed structure and improved the elongation of the epoxy resin.  相似文献   
669.
OBJECTIVE: To evaluate the use of transvaginal ultrasonography for diagnosing invasion of the bladder by cervical cancer. METHODS: Twenty-one women with stages Ib-IIIb cervical cancer underwent radical hysterectomy or staging laparotomy. All had computed tomography (CT) scans and cystoscopic examinations, and five also underwent magnetic resonance imaging (MRI). During transvaginal ultrasonography, a transvaginal transducer was inserted into the anterior fornix of the vagina and the bladder wall was studied in the sagittal plane. The moveability of the bladder wall was assessed by the ability of the bladder to slide along the uterine cervix when the probe was pushed up against the bladder from the anterior fornix. Moveability was considered to indicate an intact bladder wall. RESULTS: The accuracy of transvaginal ultrasonography was superior to that of the other methods for detecting bladder-wall invasion by cervical cancer. The accuracy was 95% for transvaginal ultrasonography, 76% for CT, 86% for cystoscopy, and 80% for MRI. CONCLUSION: Transvaginal ultrasonographic examination is useful for detecting invasion of the bladder wall by cervical cancer.  相似文献   
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