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51.
As part of a detailed study of limb defects and associated patterns of congenital malformations, cases with lower limb deficiencies were analysed separately. We identified a total of 130 cases with deficiencies of the lower limbs without defects of the upper limbs. This gives an incidence of 1.07/10,000 livebirths, or 1/9,337 for this group of limb defects. Most common were femur deficiencies and deficiencies of the foot. A preponderance of males was found in the group of transverse defects of the leg (fibula/tibia deficiencies) and central axis deficiencies, while females had significantly more often longitudinal tibia defects and preaxial ray defects. © 1993 Wiley-Liss, Inc.  相似文献   
52.
考察了开式涡轮转盘塔(OTRDC)中的分散相滞留率和液泛特性。采用五种不同的液-液体系,在两种不同直径的塔中进行了实验。给出了估算分散相滞留率的关联式及无传质时临界转速的判据,进而大体上确认了OTRDC的操作区域。  相似文献   
53.
边臻  郭源  田伟 《中华外科杂志》2006,47(1):1017-1019
Objectives To retrospectively review the results of closed reduction for developmental dysplasia of the hip (DDH), and analyze the causative for the dissatisfactory results of radiolagieal. Methods From 1997 to 2005 the results of closed reduction for DDH in 60 children (77 hips) over 4.5 years period were retrospectively reviewed. Radiological final results of the patients were evaluated with Severin classification. The causative factors made from medical records and radiographs were used to make statistical analysis. Results Seventy-three percent of the patients (56/77) had satisfactory results according to Severin classification. Twenty-one hips classed as SeverinⅢ-Ⅴ. Seventeen of the 21 hips had a reconstructive procedure. Avaseular necrosis was observed in 29 hips (38%). The most important parameters affecting the result were age at reduction (P < 0. 05) and avascular necrosis (P < 0.05).Conclusions In order to achieve better clinical and radioiogical results, the infants suffering from the DDH should be treated in the early stage. The postoperative avascular necrosis usually leads to poor prohnosis.  相似文献   
54.
Intra-articular fractures of the proximal tibia present a wide spectrum of injury patterns with associated soft tissue injury. The last two decades have seen the techniques of management evolve from extensive open reduction and rigid internal fixation to arthroscopy-assisted minimal invasive surgery (MIS) and biologically benign internal fixation. The ultimate aim is to prevent the occurrence of late degenerative arthritis. This could be achieved in selected patients using minimal invasive surgery, which offers the advantages of better visualisation and management of intra-articular soft tissue injuries, confirmation of fracture reduction viewed from the joint surface, faster rehabilitation and fewer wound complications.  相似文献   
55.
The effects of acute blood volume reduction induced by haemodialysison diastolic time intervals were studied in 19 patients by echo-and phonocardiography. Haemodialysis significantly decreasedleft ventricular diameters. The isovolumic relaxation time wasprolonged and negatively correlated with left ventricular enddiastolic dimensions. To study the effect of load reductionon left ventricular filling time, cardiac cycles with the sameR–R interval, before and after haemodialysis, were compared.At any given R–R interval dialysis resulted in a significantprolongation of the filling time. This study shows that diastolictime intervals are dependent on left ventricular loading conditions,and this effect should be considered when these time intervalsare evaluated in the clinical setting.  相似文献   
56.
The ratio of PaO2 to FiO2 was often low (300 or less) in four patients with complications of hyperosmolar hyperglycemic non-ketotic diabetic coma (HHNKDC) following open heart surgery. Four of our patients had poor oxygenation and subsequent spontaneous recovery from in the immediate post-operative period, although HHNKDC occurred only in one during this period. In the 3 others, poor oxygenation without accompanying HHNKDC lasted for 1–6 days and HHNKDC developed about 2 weeks after open heart surgery at time when poor oxygenation reoccurred. If a working diagnosis of congestive heart failure was made only on the basis of the most common probability, and the fluid supply was restricted, HHNKDC would readily occur or be aggravated by the dehydration iatrogenically produced. It is thus concluded that HHNKDC should be included in diagnoses for pulmonary dysfunction.  相似文献   
57.
The objective of this demonstration project was to determine if school-based harm minimization drug education was potentially acceptable and effective for junior and senior high school students in Nova Scotia. We conducted a four-year quasi-experimental intervention using mixed quantitative and qualitative methodologies. The intervention was a co-operative participatory research project with various activities determined by the participants. The project involved a partnership of four schools, two school boards, two regional addiction services, the provincial department of health, and a university. The outcomes evaluation was based on a sample of 1117 and 849 students in the intervention schools, compared with 3755 and 4247 students in the rest of the province, in 1998 and 2002, respectively. The evaluation of acceptability was based on an analysis of 491 documents generated from 1998 to 2002. The outcomes of effectiveness were specific risks and harmful consequences associated with substance use. We found that harm minimization was an acceptable approach to drug education targeting the senior high school population, and there was also some evidence of effectiveness in that age group in that the prevalence of several risks and negative consequences of substance use decreased significantly in the intervention schools relative to the rest of the province. In junior high school, harm minimization was found to not be an acceptable approach to drug education. This demonstration project provides evidence that school-based harm minimization may be acceptable and effective in senior high schools but may not be acceptable in junior high schools.  相似文献   
58.
To assess the curative effects of different reduction techniques on the dislocation of cricoarytenoid joint caused by intubation,indirect laryngoscope (IL) and direct laryngoscope (DL) were utilized for the closed reduction of the displaced arytenoid under local anesthesia.23 patients who underwent the reduction for dislocated arytenoid under IL or DL from January 1991 to June 2001 were reviewed.The data were collected on the duration of the laryngeal injury,times of receiving reduction,side-effects after the treatment and the period for voice to returen to normal.The relationship between the duration of the laryngeal lesion and the period of the voice rehabilitation was examined.13 patients received the reduction under IL and 10 patients under DL,Except the times of the reduction,which showed significant difference,no differences were found between IL group and DL group in the course and the period of voice rehabilitation,as well as sore throat after the manipulation.The patients‘ voice recovery was positively related to their course of disease in both IL and DL group.It is coucluded that the recovery of normal voice is obviously affected by the duration of arytenoid dislocation.The reduction under Il is as effective as under DL in the treatment of arytenoid dislocation.Reduction by DL is better suit the patients with long time course of disease.  相似文献   
59.
OBJECTIVE: Since we developed the procedure in 1996, we have now performed 100 pediatric open heart operations using a lower midline skin incision and a minimal sternotomy approach. METHODS AND RESULTS: To elucidate the benefits of this approach, we analyzed these 100 cases retrospectively. There was no death, and no major complication, caused by this approach, and the resulting scarring in each patient is difficult to be seen under a common undershirt. CONCLUSION: This review shows that the technique of a lower midline skin incision and minimal sternotomy approach is a safe reliable and cosmetically advantageous method for a pediatric cardiac operation.  相似文献   
60.
Magnetic resonance imaging maps of velocity were acquired with a 1.5-T system in 10 subjects in a plane perpendicular to the main pulmonary artery. Velocity images were successively acquired with a method developed from Fourier-encoding velocity imaging (FEVI) principles with eight gradient steps and one excitation, and with two-point phase-subtraction mapping. Reconstruction in FEVI was implemented by zero-filling interpolation around the eight gradient steps and then around the four central steps. The methods were compared by using estimates of noise in velocity measurements based on the difference between the experimental map and a smooth fitted map. For the same acquisition time, FEVI with four encoding steps was more precise in velocity measurements than phase mapping. Precision was further increased by the use of eight encoding steps, but acquisition time was doubled.  相似文献   
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