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111.
目的:总结改良Nikaidoh手术治疗右心室双出口(DORV)患者的临床经验,以提高手术疗效。方法:2例先天性心脏病右心室双出口伴肺动脉瓣狭窄行改良Nikaidoh手术,游离主动脉根部及冠状动脉,重建左心室流出道,以带单瓣牛心包片补片重建肺动脉及右心室流出道。结果:术后患者紫绀消失,复查心脏彩超仅有轻度肺动脉瓣关闭不全,未发现左、右心室流出道梗阻,康复出院。结论:采用改良Nikaidoh手术治疗伴肺动脉瓣狭窄的右室双出口,术后可获得良好的血流动力学效果,早期临床结果满意。 相似文献
112.
The reproductive activity of two species of wild rodents was studied in the Serra do Rola‐Moça State Park (PERM), in the state of Minas Gerais, Brazil. From October 1998 to October 1999 specimens of Akodon montensis (Thomas 1913) were captured in an area of seasonal semi‐deciduous forest, while specimens of Bolomys lasiurus (Lund 1840) were captured in a cerrado area (a savannah‐like grassland). The determination of the reproductive condition was based on histological and histometric analyses of testes and external characteristics of gonads. The volume of the testes, diameter of the seminiferous tubules and depth of the seminiferous epithelium were measured. Akodon montensis showed a seasonal annual reproductive cycle divided into four stages (recrudescence, activity or proliferation, regression and rest) with the reproductive activity mainly occurring during the rainy season. In contrast, B. lasiurus presented reproductive activity during almost the whole year. For both species the volume of the testes was an effective indicator of their reproductive condition. We suggest that the histological and histometric analysis of the gonads of males, together with the observations of external characteristics of gonads of males and females, may assist in identifying the reproductive condition of these animals. 相似文献
113.
Carine Brouat Caroline Tatard Khalilou Bâ Jean‐François Cosson Gauthier Dobigny Elisabeth Fichet‐Calvet Laurent Granjon Emilie Lecompte Anne Loiseau Karine Mouline Sylvain Piry Jean‐Marc Duplantier 《Journal of Biogeography》2009,36(12):2237-2250
Aim To investigate the phylogeographical structure of the Guinea multimammate mouse, Mastomys erythroleucus (Temminck, 1853), a widespread murid rodent in sub‐Saharan (Sahel and Sudan) savannas, for a better understanding of the impacts of geographical and historical factors on the evolutionary history of this species, in the context of the growing database of phylogeographical studies of African savanna mammal species. Location Sahel and Sudan savannas, Africa. Methods We sequenced the whole cytochrome b gene in 211 individuals from 59 localities distributed from Senegal to Ethiopia. Sequence data were analysed using both phylogenetic (several rooted tree‐construction methods, median‐joining networks) and population genetic methods (spatial analyses of molecular variance, mismatch distributions). Results Haplotypes were distributed into four major monophyletic groups corresponding to distinct geographical regions across a west–east axis. Diversification events were estimated to have occurred between 1.16 and 0.18 Ma. Main conclusions Vicariance events related to the fragmentation of savanna habitats during the Pleistocene era may explain the phylogeographical patterns observed. Genetic structure was consistent with a role of major Sahelian rivers as significant barriers to west–east dispersal. Recent demographic expansions probably occurred during arid phases of the Holocene with the southward expansion of savannas. 相似文献
114.
Bell K 《Medical anthropology quarterly》2005,19(2):125-148
This article explores dominant discourses surrounding male and female genital cutting. Over a similar period of time, these genital operations have separately been subjected to scrutiny and criticism. However, although critiques of female circumcision have been widely taken up, general public opinion toward male circumcision remains indifferent. This difference cannot merely be explained by the natural attributes and effects of these practices. Rather, attitudes toward genital cutting reflect historically and culturally specific understandings of the human body. In particular, I suggest that certain problematic understandings of male and female sexuality are deeply implicated in the dominant Western discourses on genital surgery. 相似文献
115.
Background
In high-risk coronary artery bypass patients; off-pump versus on-pump surgical strategies still remain a matter of debate, regarding which method results in a lower incidence of perioperative mortality and morbidity. We describe our experience in the treatment of high-risk coronary artery patients and compare patients assigned to on-pump and off-pump surgery.Methods
From March 2002 to July 2004, 86 patients with EuroSCOREs > 5 underwent myocardial revascularization with or without cardiopulmonary bypass. Patients were assigned to off-pump surgery (40) or on-pump surgery (46) based on coronary anatomy coupled with the likelihood of achieving complete revascularization.Results
Those patients undergoing off-pump surgery had significantly poorer left ventricular function than those undergoing on-pump surgery (28.6 ± 5.8% vs. 40.5 ± 7.4%, respectively, p < 0.05) and also had higher Euroscore values (7.26 ± 1.4 vs. 12.1 ± 1.8, respectively, p < 0.05). Differences between the two groups were nonsignificant with regard to number of grafts per patient, mean duration of surgery, anesthesia and operating room time, length of stay intensive care unit (ICU) and rate of postoperative atrial fibrillationConclusion
Utilization of off-pump coronary artery bypass graft (CABG) does not confer significant clinical advantages in all high-risk patients. This review suggest that off-pump coronary revascularization may represent an alternative approach for treatment of patients with Euroscore ≥ 10 and left ventricular function ≤ 30%. 相似文献116.
Background
Saphenous vein graft disease remains a major limitation of coronary artery bypass graft surgery. The process of saphenous vein intimal hyperplasia begins just days after surgical revascularization, setting the stage for graft atherosclerotic disease and its sequalae. Clopidogrel improves outcomes in patients with atherosclerotic disease, and is effective at reducing intimal hyperplasia in animal models of thrombosis. Therefore, the goal of this study will be to evaluate the efficacy of clopidogrel and aspirin therapy versus aspirin alone in the prevention of saphenous vein graft intimal hyperplasia following coronary artery bypass surgery.Methods
Patients undergoing multi-vessel coronary artery bypass grafting and in whom at least two saphenous vein grafts will be used are eligible for the study. Patients will be randomized to receive daily clopidogrel 75 mg or placebo, in addition to daily aspirin 162 mg, for a one year duration starting on the day of surgery (as soon as postoperative bleeding has been excluded). At the end of one year, all patients will undergo coronary angiography and intravascular ultrasound assessment of one saphenous vein graft as selected by randomization. The trial will be powered to test the hypothesis that clopidogrel and aspirin will reduce vein graft intimal hyperplasia by 20% compared to aspirin alone at one year following bypass surgery.Discussion
This trial is the first prospective human study that will address the question of whether clopidogrel therapy improves outcomes and reduces saphenous vein graft intimal hyperplasia following cardiac surgery. Should the combination of clopidogrel and aspirin reduce the process of vein graft intimal hyperplasia, the results of this study will help redefine modern antiplatelet management of coronary artery bypass patients. 相似文献117.
Pavlovic M Schaller A Ammann RA Sanz J Pfammatter JP Carrel T Berdat P Gallati S 《Biochemical and biophysical research communications》2005,335(3):700-704
Cardiopulmonary bypass (CPB) may induce serious side effects, potentially leading to myocardial failure. The Na(+)-K(+)-ATPase is a key component for myocardial function. Due to its developmental regulation, results from adult studies cannot be adopted to the situation in childhood. Right atrial myocardium from patients with left-to-right shunts at atrial level (VO, n=8) and those without (NO, n=8) was excised during heart surgery before and after CPB. Na(+)-K(+)-ATPase isoforms ATP1A1 (p=0.008) and ATP1A3 (p=0.038) decreased during CPB, which decrease was restricted to the VO group. This study highlights the importance of the underlying heart defect for susceptibility to the effects of CPB, showing a reduced Na(+)-K(+)-ATPase mRNA expression only in patients with left-to-right shunts on the atrial level. This seemed to be an early molecular event, as apart from one, none of the patients showed heart failure before or after surgery. 相似文献
118.
119.
Song AY Rubin JP Thomas V Dudas JR Marra KG Fernstrom MH 《Obesity (Silver Spring, Md.)》2006,14(9):1626-1636
Objective: Because post‐bariatric surgery patients undergo massive weight loss, the resulting skin excess can lead to both functional problems and profound dissatisfaction with appearance. Correcting skin excess could improve all these corollaries, including body image. Presently, few data are available documenting body image and weight‐related quality of life in this population. Research Methods and Procedures: Eighteen patients who underwent both bariatric surgery and body contouring completed our study. Both established surveys and new surveys designed specifically for the study were used to assess body perception and ideals, quality of life, and mood. Patients were surveyed at the following time‐points: pre‐body contouring (after massive weight loss) and both 3 and 6 month post‐body contouring. Statistical testing was performed using Student's t test and ANOVA. Results: The mean age of the patients was 46 ± 10 years (standard deviation). Quality of life improved after obesity surgery and was significantly enhanced after body contouring. Three months after body contouring, subjects ascribed thinner silhouettes to both current appearance and ideal body image. Body image also improved with body contouring surgery. Mood remained stable over 6 months. Discussion: Body contouring after surgical weight loss improved both quality‐of‐life measurements and body image. Initial body dissatisfaction did not correlate with mood. Body contouring improved body image but produced dissatisfaction with other parts of the body, suggesting that as patients become closer to their ideal, these ideals may shift. We further developed several new assessment methods that may prove useful in understanding these post‐surgical weight loss patients. 相似文献
120.
目前,种植义齿修复已经成为牙列缺损、缺失患者的最佳修复方式。通过对颌骨的精确测量,可获得种植手术所需相关解剖资料,为种植体的选择、设计及口腔种植手术的实施提供重要的参考。本文就口腔种植义齿相关的颌骨解剖测量进展作一综述。 相似文献