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71.
A comparative study was made on the members of the Grandparents' Club from La Salud locality, Quivicán municipality, in order to assess a host of physical and psychic parameters. The results were positive in relation to smoking, obesity and sedentariness, on the basis of preventive programs put into practice since the implementation of the family doctor plan and the grandparents' clubs. There was evidence of improvement in blood pressure requirements, presence of arthralgia, dyspnea due to efforts, normal walking and a lower mean record in the physical fitness tests. At the end of the period under study, the number of drugs taken by the elderly was lower and, from a psychic point of view the elderly people were more capable, more helpful and in general "better".  相似文献   
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BACKGROUND. Internship and residency are stressful experiences for physicians in training. Residency programs vary in their provision of supportive services for residents. METHODS. A random sample of 50% of the nation's family practice residency programs was surveyed to determine the prevalence of 19 support services, 10 of which were assessed a decade previously. Programs were also asked about on-call frequency, vacation benefits, and program size. RESULTS. Approximately 91% of the programs responded. The surveys indicated that residents were on call an average of once every four nights, a 10% decrease from a decade ago. The prevalence of three support services had increased over the last decade: seminars and speakers on the stresses and conflicts of being a physician, support groups for residents, and child care services. "Night-float" rotations and part-time residencies are the least offered support services of those studied. CONCLUSIONS. Support for family practice residents is increasing, yet in many cases remains inadequate.  相似文献   
74.
The optic tectum of the pigeon is a highly organized, multilayered structure that receives a massive polystratified afference of at least five different populations of retinal ganglion cells and gives rise to various anatomically segregated efferent systems. The synaptic organization of retino-tectal circuitry is, at present, mostly unknown. To investigate the spatiotemporal profile of synaptic activation produced by differential (electrical and visual) stimulation of the retinal inputs, we performed a high-spatial-resolution current source density analysis in the optic tectum of the anaesthetized pigeon. Electrical stimuli consisted of brief pulses of different durations applied to the optic nerve head, while visual stimuli consisted of light flashes of different intensities. Electrical stimulation generated sinks confined to retinorecipient layers. The temporal structure, spatial location and thresholds of these sinks indicated that they are all due to primary tectal synapses of retinal fibers with different conduction velocities. Sinks evoked by the fastest retinal axons were more superficially located than sinks produced by slower retinal fibers. Visual stimulation, on the other hand, resulted in a more complex pattern of current sinks, with various sinks located in the retinorecipient layers and also well below. Visual stimulation induced action potentials at superficial as well as deep tectal levels. We conclude that electrical stimulation activates most of the populations of ganglion cells as well as their primary tectal synapses, but is unable to elicit a significant activation of secondary tectal synapses. Visual stimulation, on the contrary, activates just some of the incoming retinal populations, but in a way that produces noticeable secondary activation of intratectal circuits. Laminar segregation of retinally evoked tectal activity, as reported here, has also been found in other vertebrates. Similarities and differences with previous studies are discussed.  相似文献   
75.
SGP-1/prosaposin can be secreted or targeted to the lysosomes where it is processed into smaller saposins (A, B, C, and D) required for the hydrolysis of glycosphingolipids. The deficiency of saposins B and C results in variant forms of metachromatic leukodystrophy and Gaucher's disease, respectively, which are characterized by lysosomal storage of undegraded glycosphingolipids. In the nervous system, prosaposin presents trophic activity. A mouse model was recently developed by creating a null allele in embryonic stem cells through gene targeting to investigate the phenotypic diversity of prosaposin mutations and the involvement of this protein in lysosomal storage diseases, and for the development of therapeutic approaches. Mice homozygous mutants die at the age of 35-40 days and neurological disorders contribute to the early demise of the mutant mice. The male reproductive organs in homozygous mutants show several abnormalities, such as a decrease in testis size with reduced spermiogenesis and an involution of the prostate, seminal vesicles, and epididymis. In these animals, the blood levels of testosterone remain normal. In the prostate of homozygous mutants, only the basal epithelial cells appear to be present, while the secretory cells are absent. These findings suggest that prosaposin may be involved in the development and maintenance of the male reproductive organs, as well as, in cellular differentiation.  相似文献   
76.
Aneurysms are uncommon in the pediatric age-group. Unlike adults, in which aneurysms appear after alteration of the arterial wall due to systemic diseases, in children the traumatic etiology has to be considered: blunt trauma may disrupt the arterial wall and cause false aneurysm (pseudoaneurysm). Most aneurysms are asymptomatic, or they present as a pulsatile mass on an arterial traject. Diagnosis is confirmed with Doppler ultrasound and angiography. We present the case of a girl who, after blunt trauma of the right upper limb developed a pulsatile mass on the traject of the right humeral artery. Doppler ultrasound and angiography confirmed aneurysm of the humeral artery. She was successfully treated with surgical resection of the aneurysm and reconstruction of the arterial wall.  相似文献   
77.
Pseudomyxoma peritonei is an unusual condition that has caused much confusion regarding its aetiology, clinical manifestations, treatment and prognosis. It is characterised by mucinous ascites and diffuse mucinous invasions of the peritoneum. Three histological subtypes have been defined: a) disseminated peritoneal adenomucinosis (peritoneal lesions composed of abundant extra-cellular mucin containing scant simple-to-focally-proliferating mucinous epithelium with little cytological atypia or mitotic activity); b) peritoneal mucinous carcinomatosis (peritoneal lesions composed of more abundant mucinous epithelium with the architectural and cytological features of carcinoma); and c) an intermediate group. The different histological subtypes have different prognoses. We report a case of disseminated peritoneal adenomatosis, and discuss its clinical management.  相似文献   
78.
79.
Vaquero J  Zurita M  Coca S  Oya S  Morales C 《Surgical neurology》2000,54(3):229-34; discussion 234
BACKGROUND: Keeping in mind that oligodendrogliomas have unpredictable biological behavior, the aim of this study is to investigate the prognostic significance of VEGF expression and microvessel density in a homogeneous series of low-grade oligodendrogliomas. METHODS: For this study 36 patients with a low-grade oligodendroglioma treated by surgical resection and radiotherapy were selected. At the time of surgery, in all cases the Karnofsky Performance Scale (KPS) score was more than 70, and the study of the resected tumor disclosed a Ki-67/MIB-1 labeling index (MBI-1 LI) less than 1%. In this homogeneous series, immunohistochemical studies were performed using monoclonal antibodies against VEGF in order to study the expression of this cytokine, and against vascular endothelial CD-34 antigen, in order to identify microvessels. RESULTS: Our results show that in contrast to low-grade astrocytomas, low-grade oligodendrogliomas lacked immunoreactive VEGF. Oligodendrogliomas with low vascular density (less than 20 microvessels per microscopical field, at 200 x) or high vascular density (more than 100 microvessels per field, at 200 x) were identified, but this factor had no influence on the survival rate of patients. On the other hand, analysis of the present series showed that clinical factors, such as age or extent of surgical resection, were not significantly associated with survival. CONCLUSIONS: In contrast to low-grade astrocytomas, the angiogenesis score of low-grade oligodendrogliomas (counting the number of microvessels in tumor tissue) adds little information to help predict tumor behavior.  相似文献   
80.
Apolipoprotein J (clusterin or sulfated glycoprotein-2) has been shown to be secreted by the epididymal principal cells, whereupon it binds to sperm in the lumen. Apolipoprotein J also is endocytosed by principal cells along the epididymis. Recently, it has been demonstrated that low-density lipoprotein receptor-related protein-2 (LRP-2) mediates the endocytosis of Apo J and is present in the epididymis. The purpose of the present study was to determine the factors regulating the synthesis of these 2 proteins in various experimentally treated animals. The epididymides of adult rats were fixed with Bouin's fluid and examined with anti-Apo J and anti-LRP-2 antibodies by a light microscope immunocytochemical method. In normal adult animals, expression of Apo J was evident in principal cells of all epididymal regions except the proximal initial segment. Diffuse cytoplasmic staining indicated Apo J secretion. Reactive apical vesicles, presumably endosomal in nature, suggested endocytosis of Apo J. Lipoprotein receptor-related protein-2 expression was solely apical in nature and was seen as an intense apical band in principal cells of all regions except the proximal and distal initial segment and distal caput regions of the epididymis. Hypophysectomy, up to 28 days after the procedure, did not affect expression of Apo J or LRP-2 in principal cells along the entire epididymis. Orchidectomy, with or without testosterone replacement at all time intervals examined, also did not affect LRP-2 expression along the entire epididymis. This also was noted for Apo J expression in all regions except the proximal initial segment. Thus, expression of these 2 proteins does not appear to be regulated by testicular or pituitary factors. In contrast, bilateral as well as unilateral (intact and ligated sides) efferent duct ligation resulted in dramatic differences in LRP-2 and Apo J expression in principal cells in the various epididymal regions. In the case of LRP-2, a complete absence of reaction was noted in principal cells along the entire epididymis. As for Apo J, expression in the distal initial segment, intermediate zone, and caput region remained unchanged compared with that in normal adult animals, whereas in the corpus and cauda epididymides, results of cytoplasmic staining were negligible. These results suggest that under conditions of efferent duct ligation, a circulating factor emanates from the testis to inhibit expression of LRP-2 and Apo J in these epididymal regions. Furthermore, because Apo J was affected in a region-specific manner, unlike the case for LRP-2, different factors appear to be involved for each protein. These factors may be produced to inhibit proteins from being synthesized by the epididymis in the absence of luminal testicular input and may exist in cases of congenital and pathologic epididymal tubule blockages as well as after vasectomy. In the case of immunostaining for Apo J in the proximal initial segment only, normally unreactive principal cells in control adult animals became intensely reactive after orchidectomy as well as bilateral and unilateral (ligated side only) ligation. As this was not the case for hypophysectomized animals and the intact side of unilateral efferent duct-ligated animals, it is suggested that a testicular factor entering via the lumen of the efferent ducts serves to inhibit Apo J expression in this area. The present data also reveal that after efferent duct ligation, there are circulating factors that inhibit Apo J expression in a region-specific manner (corpus and cauda) and that inhibit LRP-2 expression along the entire epididymis and that these are derived from the testis. Furthermore, the data reveal that a testicular luminal factor appears to inhibit Apo J expression in the proximal initial segment of normal adult animals. Key words: Principal cells, orchidectomy, glycoprotein 330, clusterin, sulfated glycoprotein-2.  相似文献   
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