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1.
Re-orchiopexy was performed in 33 boys (42 testes) in order to place an undescended testis in the scrotum after failure of the initial operation. Success was achieved in 80.9%. Seven of the 10 testes, reported to have short spermatic vessels at the first surgery, had no elongation of the vessels and only 1 of these resulted in a high scrotal location of the testis. It appears that most orchiopexy failures are the result of technical failures of the initial procedure. Standard orchiopexy with extensive mobilization of the spermatic vessels and testis can successfully correct most of the undescended testes. However, the preferred management for the intra-abdominal testis with short vessels may be transection of the spermatic vessels rather than a planned two-stage technique.  相似文献   
2.
The zone of progenitor cells of mandibular condyles of neonatal mice was kept in an organ culture system for up to 8 days. Qualitative and quantitative determinations indicated a pronounced proliferative activity during the initial phases of the culture followed by a differentiation phase and the acquisition of typical hyaline cartilage. The mature hypertrophic chondrocytes were found to be surrounded by cartilage-specific macromolecules such as type II collagen, cartilage proteoglycans, and cartilage anchorin. The extracellular mineralization proceeded along matrix vesicles as is usually noted in vivo. A unique finding in this study was the observation that explants comprising cartilage progenitor cells and their adjacent extracellular matrix succeeded in repairing the damaged condylar in vitro.  相似文献   
3.
The pathology and clinical features of 258 cases of mitral ring calcification were reviewed. The overall incidence in patients over 50 years of age was 8.5%; it was more than twice as high in women (11.5%) as in men (4.5%) and rose sharply with age.Cardiac failure and systolic murmurs were each noted in over half the patients. Hypertension was slightly commoner than in age- and sex-matched groups without ring calcification, although the difference was not statistically significant.Small nodules of calcification were more frequent in men and heavy deposits in women. Distortion and atrial displacement of the posterior mitral cusp was present in 26% of the hearts with early ring calcification, in 56% of the hearts with moderate, and in almost all hearts with marked changes. Systolic murmurs had been heard in 73% of these cases. ;Caseation' of the calcified ring was seen in seven hearts and haemorrhagic valvulitis in three. Calcium had ulcerated through the cusp in 12 cases, with thrombotic and/or bacterial endocarditis in five. Aortic valve calcification was present in 36% of men and was quantitatively related to the severity of mitral ring calcification. In women the incidence was 30% and there was no corresponding quantitative relationship.Microscopy showed nonspecific chronic inflammatory changes adjacent to calcium in about half the cases in both sexes, with foreign body type giant cells in 6%. Similar inflammatory changes in the valve cusp were almost twice as common in women as in men.There was no evidence that previous endocarditis was responsible for mitral ring calcification, neither did parity influence its incidence. Severe coronary atherosclerosis was unrelated but severe aortic atherosclerosis was commoner in patients with calcified mitral rings. The difference, in women, was statistically significant.The higher incidence of severe degrees of ring calcification, complications, and valvular inflammation in women suggests a sex-determined difference in tissue response in the mitral area. Possible provoking factors apply to both sexes and both left side valves, and such a difference would account for the relative frequency and sex incidence of mitral ring calcification.  相似文献   
4.
The sera of 49 healthy IgA-deficient (SIgAD) subjects were evaluated for the presence of autoantibodies directed against 10 different nuclear and cytoskeletal antigens, as well as for the presence of the common lupus anti-DNA idiotype (16/6 Id). Twenty-nine sera were from IgG subclass-deficient subjects (4 = IgG2, 25 = IgG3), and 25 from normal healthy subjects, used as controls. The incidence of antinuclear but not anti-cytoskeletal antibodies were found to be significantly greater in the SIgAD group, as compared to the IgG-deficient subjects and the normal controls. Overall, 39% of SIgAD sera demonstrated polyreactivity, namely reactivity against more than one nuclear antigen. The incidence of specific antibody detection ranged from 37% against cardiolipin to 12% against RNP in the IgA-deficient group, albeit not with statistical significance in all cases when compared to the control group. Isotype evaluation of the antinuclear and related antibodies in the SIgAD group showed a greater tendency towards IgG. This increased incidence of autoantibody production in SIgAD may preceed the development of an overt autoimmune disease in the future.  相似文献   
5.
Splenectomy has long been an establishmd surgical procedure in various conditions, including trauma. Because total splenectomy has often been correlated with sepsis, every surgeon tries to preserve as much of the injured spleen as possible. Contradictory reports have been published as to whether regeneration of the remaining splenic tissue is possible. In the present study, 28 Sprague-Dawley rats ( 100 g) were divided into four groups. They underwent two-thirds partial splenectomy; the remaining splenic tissue was examined after 1 day, 1 week, 1 month and 3 months postoperatively. The following parameters were determined: weight, length, and protein and deoxyribonucleic acid (DNA) content of the remaining spleen. The incorporation of 3H-thymidine into the remaining spleen tissue was also measured. Histology and radioautography were studied in parallel. Results were compared with control animals that were operated upon but with no partial splenectomy. One day, 1 week, and 1 month following partial splenectomy, a slight increase in weight, length, protein, and DNA content as well as incorporation of the radioisotope into cellular DNA was found. By 3 months after the operation, there was no difference in the above parameters between the experimental animals and controls.Radioautographs indicated that most of the cells containing the isotope were situated in the perinodular areas in the red pulp, accompanied by an increased number of inflammatory cells. We found this cell proliferation mainly along the cut surface of the spleen. The slight increase that was found in all the parameters examined up to 1 month after partial splenectomy is an inflammatory response and not regeneration of the spleen.  相似文献   
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Occupational stress, or job strain, resulting from a lack of balance between job demands and job control, is considered one of the frequent factors in the etiology of hypertension in modern society. Stress, with its multifactorial causes, is complex and difficult to analyze at the physiological and psychosocial levels. The possible relation between job strain and blood pressure levels has been extensively studied, but the literature is replete with conflicting results regarding the relationship between the two. Further analysis of this relationship, including the many facets of job strain, may lead to operative proposals at the individual and public health levels designed to reduce the effects on health and well-being. In this article, we review the literature on the subject, discussing the various methodologies, confounding variables, and suggested approaches for a healthier work environment.  相似文献   
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Abstract

Mentorship is essential for career development, personal development, and job satisfaction for physicians in academic medicine. Women in academic medicine face unique challenges including significant gender disparities in positions of leadership as well as difficulty finding mentors. As leaders in academic medicine, we have collated several structured recommendations for physicians of both genders seeking to be better mentors to female trainees and early career physicians. We discuss each of these recommendations in detail including the following: acknowledging your own strengths and limitations as a mentor, addressing issues of work-life integration, helping your mentee set long-term career goals, and acting as a sponsor as well as a mentor. We hope these suggestions are helpful for current and aspiring mentors and provide a platform to improve career development for female physicians and reduce gender inequities in academic medicine.  相似文献   
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