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61.
Accurate measurement of temperature at the interface of the delivery electrode and the tissue during transcatheter delivery of radiofrequency energy (RFE) for ablation would provide better control of lesion production. Electromagnetic energy fields can affect the accuracy of temperature measurement with thermistors. An electrode probe was fabricated with a thermistor and an optical sensor in the center of the delivery electrode. Simultaneous temperature measurements during RFE delivery to cardiac tissue in the 37°C bath showed good agreement between the sensors, indicating that the RFE field did not cause errors in thermistor temperature measurements with the electrode probe used. A second electrode probe was designed to determine optimal thermistor location. It was constructed using two thermistors with identical temperature-resistance curves. One thermistor protruded through a hole in the side of the delivery electrode and was thermally isolated from it. The other thermistor was bonded to the inner surface of the electrode with heat conductive epoxy. The electrode was placed in contact with cardiac tissue in a 37°C bath of flowing saline with the protruding thermistor centered in the area to be heated. Temperatures measured at steady state during RFE delivery with the protruding thermistor were consistently higher than those of the inner wall thermistor, ranging from 1.8°C difference at 46°C to 8.3°C difference at 75°C interface temperature. The thermistor must be in contact with the tissue and thermally isolated from the delivery electrode for accurate determination of electrode/tissue interface temperature.  相似文献   
62.
ABSTRACT. Two cases of necrotising enterocolitis (NEC) occurring in infants beyond the neonatal period were reported. They did not have any predisposing factors to NEC but both had paralytic ileus after loperamide therapy for their mild diarrhoea prior to the onset of NEC. The possible role of loperamide in the pathogenesis of NEC was discussed.  相似文献   
63.
Schizencephaly: diagnosis and progression in utero   总被引:2,自引:0,他引:2  
Klingensmith  WC  d; Cioffi-Ragan  DT 《Radiology》1986,159(3):617-618
Schizencephaly is an unusual condition of obscure etiology. Most theories of pathogenesis postulate an in utero insult leading to maldevelopment rather than destruction of brain. The cause has most often been described as vascular or idiopathic dysgenesis. The authors report a case in which two in utero ultrasound (US) examinations performed at 31 and 36 menstrual weeks demonstrated progressive deterioration of the relatively narrow, symmetrical clefts connecting the lateral ventricles with the subarachnoid space into broad defects that corresponded to the entire distribution of the middle cerebral arteries. The findings in this case document progressive destruction of brain tissue in utero and are consistent with a vascular cause rather than a failure of formation of portions of the cerebral mantle.  相似文献   
64.
Oral Diseases (2010) 16 , 136–145 Objective: The oral cavity forms an indispensable part of the human microbiome, for its unique and diverse microflora distributed within various niches. While majority of these organisms exhibit commensalism, shifts in bacterial community dynamics cause pathological changes within oral cavity and distant sites. The aim of this review was to appraise the current and emerging methods of detecting bacteria of the oral cavity paying particular attention to the cultivation independent methods. Design: Literature pertaining to cultivation based and cultivation independent methods of oral bacterial identification was reviewed. Methods: The specific advantages and disadvantages of cultivation based, microscopic, immunological and metagenomic identification methods were appraised. Results: Because of their fastidious and exacting growth requirements, cultivation based studies grossly underestimate the extent of bacterial diversity in these polymicrobial infections. Culture independent methods deemed more sensitive in identifying difficult to culture and novel bacterial species. Conclusion: Apart from characterizing potentially novel bacterial species, the nucleic acid sequence data analyzed using various bioinformatics protocols have revealed that there are in excess of 700 bacterial species inhabiting the mouth. Moreover, the latest pyrosequencing based methods have further broadened the extent of bacterial diversity in oral niches.  相似文献   
65.
66.
Training in interventional pulmonology procedures is increasing in popularity. However, the nature of training is difficult to define, particularly with respect to an adequate number of cases. These guidelines approach training not just from a modest number of supervised cases, but also from a range of educational and outcome targets which give a rounded approach to the issue. These include prerequisite skills from basic procedures, the place of simulated training, formal simulation testing, modest procedural outcome and side effect targets, audit presentations, ongoing reading, and hands‐on training expectations. All of this would still be under the supervision of an experienced trainer.  相似文献   
67.
A preliminary assessment of the contraceptive efficacy of a daily mild increase (1–2°c) in testicular temperature during waking hours is reported in nine couples using two techniques of non-surgical fixation of the testes close to the inguinal canal. With technique 1, immobilization was achieved by passing the penis and the empty scrotum through a hole made in close-fitting underwear; there was one pregnancy, hm a man who stopped the heating after 7 weeks, for 42 cycles of exposure in three couples. With technique 2, immobilization was achieved by adding a ring of soft material surrounding the hole in the underwear; there was no pregnancy for 117 cycles of exposure in six couples. Reversibility and safety were assessed. These preliminary results suggest that a daily mild increase in testicular temperature could be a potential contraceptive method for men.  相似文献   
68.
A retrospective analysis of 80 cases of gonococcal ophthalmia revealed six (7.5%) to be due to penicillinase-producing Neisseria gonorrhoeae (PPNG), five neonatal cases and one adult. All six cases were finally cured, but best results were obtained with topical chloramphenicol and single-dose spectinomycin (40 mg/kg) given intramuscularly. All gonococcal isolates should be tested promptly for penicillinase production, and if this is present systemic treatment, modified to spectinomycin or penicillinase-stable cephalosporin, should be given as single-dose treatment.  相似文献   
69.
目的对成都地区三所三级甲等综合医院ICU护士照护机械通气病人的态度、主观行为规范及其行为意向进行研究,为相关的护士培训提供依据。方法应用《护士对照护机械通气病人的行为态度、主观行为规范和行为意向》量表中文修订版对近三个月内照护过机械通气病人的ICU护士进行测评,描述ICU护士照护机械通气病人的态度、主观行为规范和行为意向。结果分别有69.1%、91.3%、95.8%的ICU护士对照护机械通气病人的行为态度、主观行为规范和行为意向为正性。结果绝大多数ICU护士对照护机械通气病人持积极的行为态度、主观行为规范和行为意向。  相似文献   
70.

Background  

After the WHO issued the global alert for 2009 pandemic influenza A (H1N1), many national health agencies began to screen travelers on entry in airports, ports and border crossings to try to delay local transmission.  相似文献   
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