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611.
The galE gene of Pasteurella multocida has been isolated by complementing galE-defective mutants of Salmonella typhimurium with a plasmid library of this organism. The complete nucleotide sequence of the P. multocida galE gene consists of 1017 nucleotides, encoding a predicted polypeptide of 339 amino acids. The deduced amino acid sequence displayed the highest identity (85%) to the GalE protein of Haemophilus influenzae. However, the gene organization surrounding the galE locus was different from that of H. influenzae. A galE-defective mutant of P. multocida was obtained by replacement of the active galE gene by a copy inactivated in vitro. The resulting galE mutant was highly attenuated as seen in a biological test carried out in a mouse model. 相似文献
612.
G Jonker-Pool JP van Basten HJ Hoekstra MF van Driel DT Sleijfer HS Koops HB van de Wiel 《Canadian Metallurgical Quarterly》1997,80(3):454-464
BACKGROUND: This retrospective study evaluates changes in sexual functioning after treatment for testicular cancer and investigates whether there is a relationship with different treatment modalities. METHODS: A self-reported questionnaire was sent to 337 men who had been treated for testicular cancer at the University Hospital Groningen between 1977 and 1994. Medical information was obtained from the patient records. RESULTS: A response was received from 287 men (85%); 264 patients were included in this study (78%). The mean patient age at follow-up was 37.7 years (range, 17-71 years). The mean follow-up period was 6.7 years (range, 0.25-18 years). Decrease in sexual functions was reported by 40% of patients (decrease in libido: 19%; arousal: 12% erection: 12.5%; orgasm: 19%; and ejaculation: 26%). Moreover, 23.5% of patients responding reported decreased sexual activity and 12.5% were dissatisfied with their sexual functioning. Patients with Stage II-IV nonseminoma who had been treated with polychemotherapy (PCT) with or without resection of residual retroperitoneal tumor mass (RRRTM) (PCT +/- RRRTM) reported a significantly sharper decrease in sexual functioning than patients who had been followed with a wait-and-see policy (W & S) (Stage I nonseminoma patients). It was noteworthy that patients treated by PCT alone reported more sharply decreased sexual functioning than patients treated by PCT + RRRTM. Patients treated by radiotherapy (Stage I-IIA seminoma) did not report findings significantly different from the W & S group. CONCLUSIONS: Testicular cancer patients are at risk for reduced sexual functioning, especially when treated by chemotherapy, with or without resection of residual tumor. Although chemotherapy may influence somatic aspects of sexual functioning, it appears that psychologic factors arising from the confrontation with testicular cancer play a strongly mediating (if not determining) role. 相似文献
613.
GT O'Connor JD Birkmeyer LJ Dacey HB Quinton CA Marrin NJ Birkmeyer JR Morton BJ Leavitt CT Maloney F Hernandez RA Clough WC Nugent EM Olmstead DC Charlesworth SK Plume 《Canadian Metallurgical Quarterly》1998,66(4):1323-1328
BACKGROUND: It is well known that surgeon-specific in-hospital mortality rates for coronary artery bypass grafting vary, but this aggregate measure does not suggest specific opportunities for improvement. METHODS: We performed a regional prospective study of 8,641 consecutive patients undergoing isolated coronary artery bypass grafting by all of the 23 cardiothoracic surgeons practicing in northern New England during the study period. Mode of death was assigned by an end points committee using predetermined definitions. Surgeons were ranked according to risk-adjusted mortality rates and grouped in terciles, and cause-specific mortality rates were determined. RESULTS: The mortality rate was 3.3% in the lowest surgeon mortality tercile and 5.8% in the highest tercile. Fatal heart failure accounted for 80.0% of the difference in aggregate mortality rates, ranging from 1.9% in lowest surgeon mortality tercile to 4.0% in the highest tercile (p < 0.001). Rates of other causes did not differ significantly across surgeon mortality terciles. Differences in rates of fatal heart failure could not be explained by differences in preoperative left ventricular dysfunction or other patient characteristics. CONCLUSIONS: Most of the difference in observed mortality rates across surgeons is attributable to differences in rates of heart failure. 相似文献
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617.
HB Jie CW Bailey BK Ray DM Estes N Kumar CA Carson 《Canadian Metallurgical Quarterly》1996,83(2):241-246
The glucose-6-phosphate dehydrogenase-encoding gene (G6PD) belongs to a group with constitutive expression in all tissues. The regulation of these housekeeping genes is poorly understood, as compared to what is known about many genes whose expression is restricted to a particular tissue or stage of development, and which are often regulated by locus control regions (LCR) able to act over wide distances. In order to identify sequences in human G6PD which are necessary for its expression, we have generated transgenic mice carrying a 20-kb G6PD construct, including only 2.5 kb of upstream and 2.0 kb of downstream flanking sequence. All mice which carried the transgene (TG) expressed it, and the levels of expression detected in a range of tissues from three independent lines of mice were comparable to that of the endogenous murine G6PD. The variation in enzyme activity from tissue to tissue was remarkably similar for both the TG and the endogenous gene, and was shown to be due in both cases to variations in the steady-state mRNA levels. 相似文献
618.
ME Sherman HB Friedman AE Busseniers WF Kelly TC Carner AJ Saah 《Canadian Metallurgical Quarterly》1995,8(3):270-274
Because of inconsistencies in the literature regarding popliteus and its relation to the lateral meniscus, it was decided to investigate the influence on the behavior of the lateral meniscus of contraction of the popliteus muscle via arthroscopy. A series of 50 knees from 44 patients who underwent elective arthroscopic surgery were examined. During arthroscopy, popliteus was stimulated to contract using surface electrodes. Any resultant meniscal retraction was observed and recorded. Thirty-one knees showed such retraction, and no retraction was observed in the remaining 19 knees. The clinical implications of this study are limited, but the results may support a number of proposed theories. It may be concluded that in a population exhibiting normal, intact lateral menisci, popliteus variably acts as a retractor of the lateral meniscus. 相似文献
619.
This study used the "oddball" counting paradigm to examine the possible habituation of the auditory P300 response. Twenty subjects kept a mental record of the number of rarely occurring tone pips presented in a series of more frequently occurring tone pips. Data were collected continuously until responses to 150 rare tone pips were obtained. Findings indicated that the P300 complex decreased in amplitude as a result of repeated stimulation. The decline was logarithmic, not linear, which suggests a stabilization of the amplitude over time. We suggest that the attenuation of amplitude was habituation and not a result of a recovery cycle. 相似文献
620.
HB Sayman K S?nmezoglu M Ayaz N Kahraman T Kapicioglu I Urgancioglu 《Canadian Metallurgical Quarterly》1993,37(3):115-118
Immune senescence is a multifaceted physiological syndrome of decline in the mechanisms of defence. Cofactors such as age-related associated diseases and malnutrition frequently seen in this category of the population, severely worsen the defect leading to the "immune compromised host" status. Frequency, morbidity and mortality of infections are undoubtedly largely influenced by such parameters. To date, adequate risk assessment and preventive medicine are the best approach to improve the chances of the elderly patient. 相似文献