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排序方式: 共有991条查询结果,搜索用时 15 毫秒
1.
Peter Feindt Jens Litmathe Adina B?rgens Udo Boeken Muhammed Kurt Emmeran Gams 《European journal of cardio-thoracic surgery》2007,31(4):614-617
OBJECTIVE: Enlargement of the ascending aorta is often combined with valvular, coronary, or other cardiac diseases. Reduction aortoplasty can be an optional therapy; however, indications regarding the diameter of aorta, the history of dilatation (poststenosis, bicuspid aortic valve), or the intraoperative management (wall excision, reduction suture, external reinforcement) are not established. METHODS: In a retrospective study between 1997 and 2005, we investigated 531 patients operated for aneurysm or ectasia of the ascending aorta (diameter: 45-76mm). Of these, in 50 patients, size-reducing ascending aortoplasty was performed. External reinforcement with a non-coated dacron prosthesis was added in order to stabilize the aortic wall. RESULTS: Aortoplasty was associated with aortic valve replacement in 47 cases (35 mechanical vs 12 biological), subvalvular myectomy in 29 cases, and CABG in 13 cases. The procedure was performed with low hospital mortality (2%) and a low postoperative morbidity. Computertomographic and echocardiographic diameters were significantly smaller after reduction (55.8+/-9mm down to 40.51+/-6.2mm (CT), p<0.002; 54.1+/-6.7mm preoperatively down to 38.7+/-7.1mm (echocardiography), p<0.002), with stable performance in long-term follow-up (mean follow-up time: 70 months). CONCLUSIONS: As demonstrated in this study, size reduction of the ascending aorta using aortoplasty with external reinforcement is a safe procedure with excellent long-term results. It is a therapeutic option in modern aortic surgery in patients with poststenotic dilatation of the aorta without impairment of the sinotubular junction of the aortic valve and root. 相似文献
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Gamal Kamel Muhammed Ali O. A. Danilova 《Bulletin of experimental biology and medicine》1980,89(3):364-367
The volume of the nuclei and nucleoli of certain hypothalamic centers (SON, PVN, SCN, AN, VMN) was determined in control rats and in rats after deafferentation of the mediobasal hypothalamus. Sex differences were found in the parvocellular formations of the control animals: The volumes of nuclei and nucleoli of neurons of AN and VMN, and also of the nucleolus of SCN neurons were larger in females than in males. After deafferentation of the mediobasal hypothalamus the volume of the cell nuclei was increased, especially in hypothalamic formations located outside the isolated zone. This increase was more clearly defined in rats constantly in a state of estrus after the operation. Statistically significant differences between volumes of both nuclei and nucleoli of the cells in subgroups of rats with permanent estrus and with permanent diestrus were found only in the case of SCN. No such differences were found for AN, despite the considerable difference in the constant of luteinizing hormone in the pituitary of the same rats. It is suggested that gonadotropin releasing factors are not produced by the cells of AN and that control over the succession of phases of the sex cycle may be exerted by SCN.Laboratory of Neuroendocrinology, I. M. Sechenov Institute of Evolutionary Physiology and Biochemistry, Leningrad. (Presented by Academician of the Academy of Medical Sciences of the USSR V. N. Chernigovskii.) Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 89, No. 3, pp. 352–354, March, 1980. 相似文献
4.
Gulam Muhammed Al Kibria 《Obesity research & clinical practice》2019,13(2):129-136
ObjectiveThere is a little published data on prevalence and determinants of underweight, overweight and obesity among adults in Nepal. This study analysed the cross-sectional Nepal Demographic and Health Survey (NDHS) 2016 to obtain these using the World Health Organization (WHO) and Asian-specific cutoffs of body mass index (BMI).MethodsThe 2016 NDHS used a multistage cluster-sampling design to obtain data on major health indicators in Nepal. The BMI cutoffs for underweight was <18.5 kg/m2. The BMI cutoffs for overweight/obesity as per the Asian and WHO classifications were ≥23, and ≥25 kg/m2, respectively. After reporting the prevalence according to sex and background characteristics, multilevel logistic regression was conducted to estimate odds ratios.SubjectsThis analysis included 12,652 adults (5283 males and 7369 females) with a median age of 40 years (interquartile range [IQR]: 28–54).ResultsThe overall median BMI was 21.5 kg/m2 (IQR:19.3–24.3). The overall prevalence of underweight was 16.7% (15.1% among males and 17.1% among females). The Asian-specific BMI cutoffs found the prevalence of overweight and obesity as 26.4% (27.4% among males and 25.6% among females) and 11.0% (7.7% among males and 13.3% among females), respectively. The WHO-recommended BMI cutoffs found 18.2% people overweight (16.7% among males and 19.3% among females) and 4.3% (2.5% among males and 5.6% among females) people obese. The prevalence and odds of extreme body weight categories (i.e., underweight, overweight and obesity) varied according to age, sex, education level, household wealth status, place, ecological zone and provinces of residence as per both recommended cutoffs. Overall, higher education level and wealth status were positively associated with overweight/obesity and inversely associated with underweight as per both cutoffs.ConclusionA large proportion Nepalese adults have either underweight, overweight or obesity, and could be at a greater risk of mortality and morbidity due to these extreme body weight categories. It is essential to address the factors or characteristics that are associated with the higher prevalence and likelihood of these extreme body weight categories to reduce the overall burden of underweight and overweight/obesity in Nepal. 相似文献
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Five type strains and 55 Mycobacterium tuberculosis complex clinical isolates were found resistant to trimethoprim with a MIC of >200 mg/liter and susceptible to both sulfadiazine and cotrimoxazole with a MIC90 of 10 mg/liter. Two M. canettii isolates uniquely yielded silent mutations C156 → T and G238 → C in the folP1 gene. Combined with scarce published data, these data indicate that sulfamides could be considered alternative antituberculous antibiotics. 相似文献
7.
Muhammed Olanrewaju Afolabi Nuala McGrath Umberto D’Alessandro Beate Kampmann Egeruan B Imoukhuede Raffaella M Ravinetto Neal Alexander Heidi J Larson Daniel Chandramohan Kalifa Bojang 《Bulletin of the World Health Organization》2015,93(5):320-328A
ObjectiveTo assess the effectiveness of a multimedia informed consent tool for adults participating in a clinical trial in the Gambia.MethodsAdults eligible for inclusion in a malaria treatment trial (n = 311) were randomized to receive information needed for informed consent using either a multimedia tool (intervention arm) or a standard procedure (control arm). A computerized, audio questionnaire was used to assess participants’ comprehension of informed consent. This was done immediately after consent had been obtained (at day 0) and at subsequent follow-up visits (days 7, 14, 21 and 28). The acceptability and ease of use of the multimedia tool were assessed in focus groups.FindingsOn day 0, the median comprehension score in the intervention arm was 64% compared with 40% in the control arm (P = 0.042). The difference remained significant at all follow-up visits. Poorer comprehension was independently associated with female sex (odds ratio, OR: 0.29; 95% confidence interval, CI: 0.12–0.70) and residing in Jahaly rather than Basse province (OR: 0.33; 95% CI: 0.13–0.82). There was no significant independent association with educational level. The risk that a participant’s comprehension score would drop to half of the initial value was lower in the intervention arm (hazard ratio 0.22, 95% CI: 0.16–0.31). Overall, 70% (42/60) of focus group participants from the intervention arm found the multimedia tool clear and easy to understand.ConclusionA multimedia informed consent tool significantly improved comprehension and retention of consent information by research participants with low levels of literacy. 相似文献
8.
The potential use of unmanned aircraft systems (drones) in mountain search and rescue operations 总被引:4,自引:0,他引:4
Yunus Karaca Mustafa Cicek Ozgur Tatli Aynur Sahin Sinan Pasli Muhammed Fatih Beser Suleyman Turedi 《The American journal of emergency medicine》2018,36(4):583-588
Objective
This study explores the potential use of drones in searching for and locating victims and of motorized transportation of search and rescue providers in a mountain environment using a simulation model.Methods
This prospective randomized simulation study was performed in order to compare two different search and rescue techniques in searching for an unconscious victim on snow-covered ground. In the control arm, the Classical Line Search Technique (CLT) was used, in which the search is performed on foot and the victim is reached on foot. In the intervention arm, the Drone-snowmobile Technique (DST) was used, the search being performed by drone and the victim reached by snowmobile. The primary outcome of the study was the comparison of the two search and rescue techniques in terms of first human contact time.Results
Twenty search and rescue operations were conducted in this study. Median time to arrival at the mannequin was 57.3 min for CLT, compared to 8.9 min for DST. The median value of the total searched area was 88,322.0 m2 for CLT and 228,613.0 m2 for DST. The median area searched per minute was 1489.6 m2 for CLT and 32,979.9 m2 for DST (p < 0.01 for all comparisons).Conclusions
In conclusion, a wider area can be searched faster by drone using DST compared to the classical technique, and the victim can be located faster and reached earlier with rescuers transported by snowmobile. 相似文献9.
10.
Rosa Porrovecchio Muhammed Babakir‐Mina Maria Cristina Rapanotti William Arcese Carlo Federico Perno Marco Ciotti 《Journal of medical virology》2013,85(6):1122-1124
Primary infection with KIPyV and WUPyV polyomaviruses occurs early in childhood followed by lifelong persistence in the body. Polyomavirus reactivation can occur in the presence of impaired immunity as in hematological malignancies or during immunosuppresssion induced by medications. In this study, reactivation of KIPyV and WUPyV was monitored by conventional PCR in plasma samples of 26 stem cell transplant patients and in 26 related bone marrow donors. Plasma samples from transplant patients were collected immediately after the end of conditioning regimen and up to 270 days after transplant. All plasma samples from transplant patients were negative for KIPyV and WUPyV DNA. Instead, KIPyV DNA was detected in two bone marrow donors. There was no evidence of KIPyV transmission from the donor to the recipient. The data suggest that detection of KIPyV in plasma is sporadic and that KPIyV and WUPyV do not affect the post‐transplant clinical course. However, further studies on a larger sample size and more sensitive PCR methods are needed to confirm these observations. J. Med. Virol. 85: 1122–1124, 2013. © 2013 Wiley Periodicals, Inc. 相似文献