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51.
To identify the predictive factors for testicular sperm extraction (TESE) and to understand the pathology associated with TESE, we carried out a prospective study in 40 consecutive men with azoospermia due to primary gonadal failure. The main outcome measure was the retrieval of at least one testicular spermatozoon. Endocrine and biophysical profiles, testicular histology, Johnsen score and testicular spermatids were used as predictors of sperm extraction. Spermatogenesis was quantified with the Johnsen score. A variable pattern of spermatogenesis was common, being present in 20 (50%) patients. Visualisation of testicular spermatids on testicular histology showed a strong association with TESE (P < 0.0001). Statistically significant differences were detected in plasma follicle stimulating hormone (FSH) and testicular volume between patients who had hypospermatogenesis and Sertoli cell-only or maturation arrest. There were no significant differences in Johnsen score, biophysical and endocrine profiles between the groups with successful and failed TESE. However, a statistically significant trend occurred with changes in histological pattern [chi2 for trend, P = 0.001; Pearson's coefficient (r) = 0.6], Johnsen score (P = 0.022; r = 0.5), testicular volume (P = 0.01; r = 0.5) and plasma FSH concentrations (P = 0.044; r = 0.4), albeit to a limited degree. Difference in the interpretation of histological patterns with different assessors was observed. The type of occupation or risk factors for azoospermia showed no association with testicular pathology or TESE. Variable histological patterns in different tubules in the same individual may explain the poor correlation of TESE with endocrine and biophysical profiles, Johnsen score and histological pattern. Differences in the amount of tissue used for TESE and histopathology, and misinterpretation of testicular histology rather than failure to quantify spermatogenesis may explain the poor correlation between histological patterns and TESE. Testicular spermatids predicted TESE. However, considerable overlap in values means that no single variable can provide a perfect discrimination between the groups with successful and failed TESE.   相似文献   
52.
Two modes of embryo transfer, uterine and tubal, were compared following natural cycle in-vitro fertilization (IVF). Only patients with patent Fallopian tubes were included in the study. Tubal embryo transfer was performed by retrograde tubal cannulation without analgesia on an outpatient basis. Tubal transfer conferred no benefit compared with uterine transfer in male factor infertility with positive fertilization (pregnancy rates of 15.8% in both groups). Although tubal embryo transfer in the patients with unexplained infertility improved the pregnancy rates from 7.8% in uterine transfer (5/64) to 17.6% in the tubal transfer group (13/74), this improvement was not statistically significant.   相似文献   
53.

Purpose

The purpose of this study is to clarify morphological changes of acetabular subchondral bone cyst after total hip arthroplasty for osteoarthritis secondary to developmental dysplasia of the hip.

Methods

Two hundred and sixty-one primary cementless total hip arthroplasties of 208 patients, 18 males, 190 females, were retrospectively reviewed. Morphological changes of subchondral bone cyst were evaluated by computed tomography (CT). The mean cross-sectional area of the cyst from CT scans at 3 months postoperatively and after 7–10 years (average 8.4 years) were compared.

Results

Acetabular subchondral bone cysts were found in 49.0% of all cases in preoperative CT scans. There was no cyst which was newly recognized in CT scan performed after postoperative 7–10 years. All the cross-sectional areas of the cysts evaluated in this study were reduced postoperatively.

Conclusions

This study revealed that acetabular subchondral bone cysts do not increase or expand after total hip arthroplasty and indicated that the longitudinal morphological change of acetabular bone cysts in patients of developmental dysplasia of the hip do not influence long-term implant fixation in total hip arthroplasty.
  相似文献   
54.
Primitive human hematopoietic precursors express Bcl-x but not Bcl-2   总被引:10,自引:3,他引:7  
Park  JR; Bernstein  ID; Hockenbery  DM 《Blood》1995,86(3):868-876
  相似文献   
55.
56.
General-purpose radiation transport Monte Carlo codes have been used for estimation of the absorbed dose distribution in external photon and electron beam radiotherapy patients since several decades. Results obtained with these codes are usually more accurate than those provided by treatment planning systems based on non-stochastic methods. Traditionally, absorbed dose computations based on general-purpose Monte Carlo codes have been used only for research, owing to the difficulties associated with setting up a simulation and the long computation time required. To take advantage of radiation transport Monte Carlo codes applied to routine clinical practice, researchers and private companies have developed treatment planning and dose verification systems that are partly or fully based on fast Monte Carlo algorithms. This review presents a comprehensive list of the currently existing Monte Carlo systems that can be used to calculate or verify an external photon and electron beam radiotherapy treatment plan. Particular attention is given to those systems that are distributed, either freely or commercially, and that do not require programming tasks from the end user. These systems are compared in terms of features and the simulation time required to compute a set of benchmark calculations.  相似文献   
57.

Purpose

Variability in functional outcome after ileal pouch-anal anastomosis (IPAA) is to a large extent unexplained. The aim of this study was to use MRI to evaluate the morphology, emptying pattern and other pathology that may explain differences in functional outcome between well-functioning and poorly functioning pouch patients. A secondary aim was to establish a reference of normal MRI findings in pelvic pouch patients.

Methods

From a previous study, the best and worst functioning patients undergoing IPAA surgery between 2000 and 2013 had been identified and examined with manovolumetric tests (N?=?47). The patients were invited to do a pelvic MRI investigating pouch morphology and emptying patterns, followed by a pouch endoscopy.

Results

Forty-three patients underwent MRI examination. We found no significant morphological or dynamic differences between the well-functioning and poorly functioning pouch patients. There was no correlation between urge volume and the volume of the bony pelvis, and no correlation between emptying difficulties or leakage and dynamic MRI findings. Morphological MRI signs of inflammation were present in the majority of patients and were not correlated to histological signs of inflammation. Of the radiological signs of inflammation, only pouch wall thickness correlated to endoscopic pouchitis disease activity index scores.

Conclusion

It seems MRI does not increase the understanding of factors contributing to functional outcome after ileal pouch-anal anastomosis. Unless there is a clinical suspicion of perianal/peripouch disease or pelvic sepsis, MRI does not add value as a diagnostic tool for pelvic pouch patients. Endoscopy remains the golden standard for diagnosing pouch inflammation.
  相似文献   
58.
Oral Diseases (2012) 19 , 37–45 Inflammatory ulcerative diseases of the oral mucosa are wide ranging but include especially aphthous and aphthous‐like ulceration, vesiculobullous disorders and erosive lichen planus (LP). While most patients with these conditions respond to conventional topical and/or systemic immunosuppressive agents, treatment‐resistant cases remain challenging. In these, the use of biologics such as tumour necrosis factor alpha (TNF‐α) inhibitors or rituximab may be of benefit. This article reviews the use of biologics in ulcerative oral conditions, highlighting potential benefits, adverse effects and principles of use and future developments. TNF‐α inhibitors such as infliximab can be effective in inducing resolution in oral aphthous and aphthous‐like ulcers and may be an appropriate therapy in those patients in which disease is severe and refractory to, or patients are intolerant of, traditional immunomodulatory regimens. There would also seem support and rationale for use of biologics (mainly rituximab) in pemphigus but not in oral LP or other oral ulcerative conditions.  相似文献   
59.
Tetralogy of Fallot is generally considered to be the most common congenital heart defect associated with an aberrant subclavian artery (ASA), but the prevalence of ASA in patients with other cardiac anomalies is not well described. The pediatric echocardiography database, with 15,871 initial echocardiograms, was searched for all patients with ASA. Arch laterality and associated intracardiac anomalies were documented for each patient. ASA was found in 226 patients, of whom 171 had a left aortic arch (LAA) and 55 had a right aortic arch (RAA). The occurrence of ASA was 1% in patients with LAA (171 of 15,650) and 25% in patients with RAA (55 of 221; p = 0.001). Intracardiac anatomy was normal in 32% of patients with ASA/LAA and 25% with ASA/RAA. Conotruncal anomalies occurred more frequently with ASA/RAA than ASA/LAA (36% vs 18%; p = 0.01). Atrioventricular canal defects accounted for 10% and left-sided cardiac obstructive lesions accounted for 11% of subjects with ASA/LAA. ASA was rarely associated with d-transposition of the great arteries (1 of 226) and double-outlet right ventricle (5 of 226). The prevalence of ASA was highest in patients with interrupted aortic arch (11 of 38; 29%). In patients with tetralogy of Fallot, the overall prevalence of ASA was 8% (34 of 447), but was higher with RAA (16 of 103; 16%). The highest prevalence of ASA occurred in the subgroup of patients with tetralogy of Fallot with pulmonary atresia and RAA (6 of 25; 24%). In conclusion, ASA was more common in patients with RAA, especially with conotruncal anomalies. In patients with LAA, hypoplastic left heart syndrome, aortic coarctation, and atrioventricular canal defects were commonly associated with ASA.  相似文献   
60.
Purpose: To review and characterise biomechanical approaches for the measurement of spasticity as one component of the upper motor neurone syndrome. Method: Systematic literature searches based on defined constructs and a four-step review process of approaches used or described to measure spasticity, its association with function or associated phenomena. Most approaches were limited to individual joints and therefore, to reflect this trend, references were grouped according to which body joint(s) were investigated or whether it addressed a functional activity. For each joint, references were further sub-divided into the types of measurement method described. Results: A database of 335 references was established for the review process. The knee, ankle and elbow joints were the most popular, perhaps reflecting the assumption that they are mono-planar in movement and therefore simpler to assess. Seven measurement methods were identified: five involving passive movement (manual, controlled displacement, controlled torque, gravitational and tendon tap) and two involving active movement (voluntary and functional). Generally, the equipment described was in an experimental stage and there was a lack of information on system properties, such as accuracy or reliability. Patient testing was either by cohort or case studies. The review also conveyed the myriad of interpretations of the concept of spasticity. Conclusions: Though biomechanical approaches provide quantitative data, the review highlighted several limitations that have prevented them being established as an appropriate method for clinical application to measure spasticity.  相似文献   
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