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91.
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We investigated the effect of multiple freeze-thaw cycles on mumps, measles, and rubella virus serum antibody levels with whole-virus immunoglobulin G enzyme-linked immunoassays. Fresh serum samples from nine healthy adult volunteers were divided into six sets of five aliquots each. Samples were taken through a total of 10 freeze-thaw cycles and stored at 4°C until assayed. Each assay measurement was done in replicates of five, and the mean value was reported. After completing 10 freeze-thaw cycles, we found no clinically or statistically significant effect on measured antibody levels and found no discernible detrimental effect on the ability to measure these antibodies by enzyme-linked immunoassays.  相似文献   
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The purpose of this article is to describe the extent to which certified nurse-midwives (CNMs) provide care to vulnerable populations in the United States and the source of reimbursement for this care. The data were obtained from the first phase of a national study to address the characteristics of women served and cost of care provided by CNMs. Results were analyzed nationally and by American College of Nurse-Midwives regions. Certified nurse-midwives in all types of practices are providing care to women from populations that are vulnerable to poorer than average outcomes of childbirth because of age, socioeconomic status, refugee status, and ethnicity. Ninety-nine percent of CNMs report serving at least one group of vulnerable women, and CNMs in the inner city and rural practices serve several groups. The vast majority of CNMs are salaried; only 11% receive their primary income from fee-for-service. Fifty percent of the payment for CNM services is from Medicaid and government-subsidized sources whereas less than 20% comes from private insurance. Source of income varies by type of setting in which the CNM attends births. The results suggest that CNMs, as a group, make a major contribution to the care of vulnerable populations.  相似文献   
94.
Self-expanding endovascular graft: an experimental study in dogs   总被引:2,自引:0,他引:2  
An arterial endovascular graft was constructed by wrapping an expandable nylon mesh around a framework of Gianturco self-expanding metallic stents. The devices were passed through a 12-French Teflon catheter and positioned in the normal abdominal aorta of five dogs, two of which also had a device placed in an external iliac artery. At follow-up (1-6 months), all grafts remained patent, even though slight luminal narrowing due to neointimal encasement was noted. Histologically, all grafts were covered by neointimal proliferation at the time of removal. The graft material expanded with the stents, resulting in a tight fit between the graft and the vessel wall. Side branches narrowed but remained open because of the size of the nylon mesh. No migration of the grafts equipped with a barbed lead stent was noted. Expandable nylon mesh can be used as an endovascular graft material when wrapped around a framework of self-expanding stents. The resulting device can be easily delivered via transcatheter techniques, and once placed in a vessel, the nylon acts as a support for neointimal encasement, which forms a new vascular lumen.  相似文献   
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Attitudes to childhood in general and towards one's own childhood in particular are compared in a survey of 152 Australian and New Zealand child psychiatric and paediatric trainees. Results confirm the findings of Enzer et al that paediatricians view childhood more positively than do child psychiatrists. Although there is a significant difference between the two groups on measures of their perceptions of the parenting they received with child psychiatrists rating their own parents as less caring than do paediatricians, there is no relationship between attitudes to childhood and perceptions of the parenting they received. Implications of these findings are examined, both in terms of motivation for choosing one or other specialty and for the working relationship between the two professions.  相似文献   
98.
Syndromes involving peptide or nonsex steroid hormone secretion due to aberrantly located tumors are rare. We report a collected series of 16 patients with ectopic hormone production from ovarian neoplasms, including 3 patients recently encountered at our institution as well as 13 additional cases identified in the recent literature. These tumors included 2 insulin-producing ovarian carcinoids, 1 ACTH-producing pituitary adenoma within a benign ovarian cystic teratoma, 2 cortisol-producing ovarian neoplasms, 8 gastrin-producing ovarian cystadenomata or cystadenocarcinomata, and 3 thyroxine-producing ovarian strumal carcinoids. All patients presented with syndromes of hormone excess. Only 62% of all tumors were localized preoperatively. Following ovarian resection, 87% of patients remained disease-free with a median follow-up period of 1.5 years. In addition to ovariectomy, 8 additional unnecessary ablative procedures were performed in 7 patients. These included distal pancreatectomy, pancreaticoduodenectomy, adrenalectomy, total gastrectomy, selective vagotomy, and subtotal thyroidectomy. Failure to localize the ovarian neoplasm preoperatively was associated with a significantly higher risk of subsequent unnecessary ablative procedures. Because of the potential for the ovary to act as a source of aberrant hormone secretion, we recommend complete preoperative evaluation of the pelvis in female patients presenting with nonlocalizable endocrine tumors.
Resumen Los síndromes relacionados con la secreción de péptidos o de hormonas esteroideas no sexuales por tumores de ubicación aberrante ocurren infrecuentemente. En este artículo reportamos una serie de 16 pacientes con producción hormonal ectópica por neoplasmas ováricos, la cual incluye 3 pacientes vistos recientemente en nuestra institución y 13 identificados en la literatura médica de los últimos años. El grupo incluye 2 carcinoides ováricos productores de insulina, 1 adenoma pituitario productor de ACTH, 2 neoplasmas ováricos productores de cortisol, 8 cistadenomas o cistadenocarcinomas ováricos productores de gastrina, y 3 carcinoides ováricos estrumales productores de tiroxina. Todas las pacientes se presentaron con síndromes de exceso hormonal. En sólo el 62% de los tumores se pudo establecer la ubicación anatómica en la fase preoperatoria. Después de realizada la resección del ovario, 87% de las pacientes permanecieron libres de enfermedad en el período de seguimiento, que fue de 1.5 años en promedio. Además de la resección ovárica, se practicaron otros 8 procedimientos adicionales innecesarios en 7 pacientes. Estos incluyeron pancreatectomía distal, pancreatoduodenectomía, adrenalectomía, gatrectomía total, vagotomía selectiva, y tiroidectomía subtotal. La falla en la localización preoperatoria del neoplasma ovárico apareció asociada con un riesgo aumentado de ulteriores procedimientos quirúrgicos innecesarios. En vista de la potencialidad del ovario de actuar como fuente de secreción hormonal aberrante, nosotros recomendamos una completa evaluación de la pelvis en las pacientes femeninas en quienes se diagnostiquen tumores endocrinos no localizables.

Résumé Les syndromes concernant la sécrétion d'hormones peptidique ou stéroïde nonsexuelle due à des tumeurs ectopiques sont rares. Nous rapportons une série de 16 patientes avec une production d'hormone ectopique provenant de néoplasmes ovariens, comprenant 3 patientes récemment soignées dans notre établissement ainsi que 13 cas supplémentaires relevés dans la littérature récente. Ces tumeurs comprennent 2 tumeurs carcinoïdes ovariennes productrices d'insuline, 1 adénome hypophysaire producteur d'ACTH à l'intérieur d'un tératome cystique ovarien bénin, 2 néoplasmes ovariens producteurs de cortisol, 8 cystadénomes ou cystadénocarcinomes ovariens producteurs de gastrine, et 3 carcinoïdes ovariens strumaux producteurs de thyroxine. Toutes les patientes avaient des syndromes d'hyperproduction hormonale. Soixante-deux pour cent seulement des tumeurs avaient été localisées en préopératoire. Après ovariectomie, 87% des patientes étaient apparamment sans récidive avec un suivi médian d'un an et demi. Cependent, outre l'ovariectomie, 8 interventions supplémentaires non nécessaires ont été accomplis chez 7 patientes. Celles-ci comprenaient: pancréatectomie distale, duodénopancréatectomie, surrénalectomie, gastrectomie totale, vagotomie sélective, et thyroïdectomie subtotale. L'impossibilité de localiser le néoplasme ovarien en période préopératoire était associée à un risque notoirement plus grand de faire une résection inutile. Compte tenu de la possibilité pour l'ovaire de se comporter en producteur de sécrétion ectopique d'hormone, nous recommandons un examen complet préopératoire du bassin chez les femmes se présentant avec des tumeurs endocrines non localisables.


Presented at the International Association of Endocrine Surgeons in Toronto, Ontario, Canada, September, 1989.  相似文献   
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The gustatory and olfactory basis of learned alcohol aversions was examined by testing rats with either gustatory neocortex ablations, olfactory bulb ablations, or a combination of both ablations. In the first experiment operated rats were compared with control rats in the acquisition of a learned alcohol aversion. In the second experiment, the effect of ablations on preoperatively-learned alcohol aversions was examined. Rats lacking gustatory neocortex learned and retained alcohol aversions normally although these rats extinguished the aversions faster than normal rats. Olfactory bulb ablation alone failed to disrupt normal aversion learning but completely eliminated retention of a previously acquired aversion. Combination ablations produced severe deficits both in acquisition and retention of learned alcohol aversions. The results indicate that, besides having gustatory qualities, the odor quality of alcohol is important in determining the associative and memorial characteristics of alcohol.  相似文献   
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