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11.
We report a case of V ventricular cystic dilatation, presenting with specific neurological symptoms including low back pain, bilateral sciatica, weakness of dorsiflexion, and urinary retention. MRI showed a large cystic dilatation of the ventriculus terminalis. Surgical fenestration of the cyst allowed complete relief from symptoms and remission of the neurological deficit.  相似文献   
12.
Despite the potential utility of calcium supplementation and the availability of many calcium supplements in the market, there are few data concerning the absorbability of different calcium salts in different conditions. We have compared the acute metabolic responses following oral administration of calcium citrate (CC) or calcium gluconolactate and carbonate (CGC) given to 20 healthy perimenopausal women (aged 48–55 years). Ten women received two effervescent tablets of CC (each containing 500 mg of calcium) and 10 women received two effervescent tablets of CGC (each containing 500 mg of calcium). Before and on an hourly basis for 6 hours, serum total and ionized calcium, phosphate, and immunoreactive parathyroid hormone (iPTH) were measured. Urinary calcium and creatinine were also measured. Both calcium salts induced significant increase in serum total and ionized calcium and in urinary calcium excretion; they also significantly reduced circulating levels of iPTH. The analysis of ionized calcium and iPTH response curves to CC and CGC administration revealed a significantly greater bioavailability of CC compared with CGC. Our data suggest that CC could be prefered to CGC for its characteristics of absorbability and bioavailability.  相似文献   
13.
The diagnostic sensitivity of Ultrasound (US) was studied in 142 children with suspected kidney and urinary tract malformations. According to the clinical tests performed the patients underwent excretory urography (EU) and/or voiding cystouretrography (VCU); the results were compared to US findings. In the 75 patients with malformations, US proved to be extremely sensitive in abdominal renal ectopies, in "horseshoe" kidney, and in congenital obstructions of the ureteropelvic and vesico-ureteral junctions. US showed a higher sensitivity than EU in identifying multicystic kidney and in most cases of hypodysplasia. On the other hand, VCU was more accurate in vesico-ureteral reflux studies; US should thus be used in the follow-up of the patients undergoing medical therapy. EU must however be considered as the most important tool in the evaluation of early renal injuries and their possible development.  相似文献   
14.
Using a commercially available monoclonal antibody (Ks20.1) and the avidin-biotin peroxidase method on cytospins and cell blocks, we analyzed cytokeratin (CK) 20 expression in 169 serous effusions. Cytoplasmic staining was observed in 44/151 malignant fluids. Colon, gastric, and pancreatic adenocarcinomas and mucinous ovarian tumors were most frequently positive. Single cases of transitional-cell and squamous cell carcinomas were reactive as well. Lung and breast cancers were mostly negative. Nonmucinous ovarian tumors were invariably unlabeled as were mesotheliomas and normal mesothelial cells. the study shows that CK 20 is valuable in distinguishing tumor cell origin in effusions. in particular, it identifies a set of carcinomas with the majority arising from the gastrointestinal tract, and represents a highly characteristic marker for colorectal cancer. © 1995 Wiley- Liss, Inc.  相似文献   
15.
The skeletal structures of the face and throat are derived from cranial neural crest cells (NCCs) that migrate from the embryonic neural tube into a series of branchial arches (BAs). The first arch (BA1) gives rise to the upper and lower jaw cartilages, whereas hyoid structures are generated from the second arch (BA2). The Hox paralogue group 2 (PG2) genes, Hoxa2 and Hoxb2, show distinct roles for hyoid patterning in tetrapods and fishes. In the mouse, Hoxa2 acts as a selector of hyoid identity, while its paralogue Hoxb2 is not required. On the contrary, in zebrafish Hoxa2 and Hoxb2 are functionally redundant for hyoid arch patterning. Here, we show that in Xenopus embryos morpholino-induced functional knockdown of Hoxa2 is sufficient to induce homeotic changes of the second arch cartilage. Moreover, Hoxb2 is downregulated in the BA2 of Xenopus embryos, even though initially expressed in second arch NCCs, similar to mouse and unlike in zebrafish. Finally, Xbap, a gene involved in jaw joint formation, is selectively upregulated in the BA2 of Hoxa2 knocked-down frog embryos, supporting a hyoid to mandibular change of NCC identity. Thus, in Xenopus Hoxa2 does not act redundantly with Hoxb2 for BA2 patterning, similar to mouse and unlike in fish. These data bring novel insights into the regulation of Hox PG2 genes and hyoid patterning in vertebrate evolution and suggest that Hoxa2 function is required at late stages of BA2 development.  相似文献   
16.
The results of electron microscopic examination of cytologic specimens from six cases of mesothelioma and 10 cases of metastatic carcinoma of different origins are presented. The formation of cell clusters in malignant effusions from the two neoplasms has been thoroughly investigated: in mesotheliomas, cells had longer, more slender microvilli than in carcinomas and more abundant bundles of intermediate filaments; the central cavity often seen in the clusters frequently contained collagen and showed basement membrane production. The application of periodic acid-silver methenamine (PASM) and phosphotungstic acid (PTA) demonstrated a peculiar ultrastructural difference in cell coat staining in the two tumor types: in mesotheliomas, PTA and PASM were consistently negative along the outer surface of the cell aggregates, while carcinomas displayed a positive reaction either on the outer surface or on both inner and outer surfaces of the clusters. The diagnostic significance of the above-mentioned difference between the two neoplasms will require further investigation in a larger number of cases.  相似文献   
17.
Summary To evaluate the antiemetic effectiveness and toxicity of a novel congener of metoclopramide (MCP), alizapride (AZP), 29 patients receiving cisplatin (50 mg/m2) alone or with adriamycin (40 mg/m2) were entered into a randomized cross-over trial comparing moderate-dose AZP (2 mg/kg for 4 doses) administered alone or with dexamethasone (DXM) (8 mg for five doses) vs a standard combination of MCP (1 mg/kg for four doses) and DXM (as above). With the dosage and schedule used, AZP provided only limited antiemetic protection, with less than 10% of the patients free of emesis. The AZP-DXM combination was significantly more effective than AZP alone in reducing the intensity of the emesis (P<0.03). The incidence, however, was statistically unaffected. The additional toxicity of DXM was negligible. Except for the patients' preference for MCP-DXM (P<0.01), no differences could be found between the DXM-based regimens, although a trend towards a better antiemetic effect with the MCP combination was evident. The benzamide-related dystonic reactions were equally distributed. Among the 11 patients affected there were 6 who required specific treatments. Unfavourable prognostic factors in the patient population could provide a reasonable explanation for the disappointing antiemetic protection obtained with all the regimens evaluated in this study.Supported in part by a grant from the Ministero della Sanita' Controllo dell'emesi indotta da agenti antineoplastici  相似文献   
18.
Frailty is the major expression of accelerated aging and describes a decreased resistance to stressors, and consequently an increased vulnerability to additional diseases in elderly people. The vascular aging related to frail phenotype reflects the high susceptibility for cardiovascular diseases and negative postoperative outcomes after cardiac surgery. Sarcopenia can be considered a biological substrate of physical frailty. Malnutrition and physical inactivity play a key role in the pathogenesis of sarcopenia. We searched on Medline (PubMed) and Scopus for relevant literature published over the last 10 years and analyzed the strong correlation between frailty, sarcopenia and cardiovascular diseases in elderly patient. In our opinion, a right food intake and moderate intensity resistance exercise are mandatory in order to better prepare patients undergoing cardiac operation.  相似文献   
19.
Summary Capsaicin-sensitive sensory neurons of the rabbit iris, by releasing tachykinins, exert a major role in the control of pupil motility in response to various noxious stimuli. However, the contribution of sensory innervation to the regulation of iris smooth muscle tone in other mammals species is not known. We have studied the effects produced by electrical field stimulation, capsaicin, substance P, neurokinin A, calcitonin gene-related peptide (CGRP), and bradykinin in the isolated iris sphincter muscle of the pig.Capsaicin (10 M): a) contracted the isolated sphincter muscle and; b) released immunoreactivity for substance P (SP-LI) and CGRP (CGRP-LI) from this preparation. These two effects were no longer observed at the second exposure to the drug. Electrical field stimulation (10 Hz, 60 V, 0.5 ms for 5 s) produced a biphasic contractile response. The rapid component was inhibited by atropine (1 M), while the delayed response was blocked by previous exposure to capsaicin (10 M).Substance P and neurokinin A consistently produced contraction of the pig iris sphincter muscle, substance P being more potent than neurokinin A. CGRP induced a contractile response in more than 50% of the preparations. The tachykinin antagonist [D-Argl, D-Trp7,9, Leu11-substance P (3 M) blocked: a) the effect of substance P (1 nM); b) the delayed response to electrical field stimulation and; c) reduced by more than 50% response to capsaicin. Bradykinin (10 M) failed to release either SP-LI or CGRP-LI. The contractile response evoked by bradykinin was unaffected by in vitro pretreatment with capsaicin (10 M).The existence in the pig iris of capsaicin-sensitive sensory fibres releasing neuropeptides and thus regulating sphincter muscle tone is proposed. Send offprint requests to Dr. P. Geppetti at the above address  相似文献   
20.
A teaching course in laparoscopic surgery was addressed to 21 young postgraduates as a part of their general surgery program with the aim of making them familiar with the basic principles of laparoscopic surgery. The methodology was based on tutorial teaching and learning by problems; the students worked in little groups elaborating check lists, discussing problems, and practising with laparoscopic training devices. Theoretical learning, practical abilities, and efficacy of tutorial teaching were investigated at the end of the course: the participant's understanding of instrument function, mastering of equipment, and solutions to clinical problems were good, as were the efficiency and pleasantness of the didactic method. Tutorial teaching seems to be a valid model for basic training in laparoscopic surgery in a modern medical education program.  相似文献   
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