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51.
We report the case of a 34-year-old Japanese man suffering from a nephrogenic diabetes insipidus (NDI) associated with bilateral hydronephrosis, hydroureters and enlarged trabeculated bladder without obstruction. He also presented with chronic renal failure which has rarely occurred in similar cases. The patient was admitted after a traumatic rupture of the left urinary tract which had never been described until now in NDI. He was treated successfully by transient peritoneal and vesical drainages. This paper focuses on the very rare complication of chronic renal failure secondary to hydronephrosis in cases of NDI. The literature of this association is reviewed.  相似文献   
52.
Proton beam therapy uses positively charged particles, protons, whose physical properties improve dose-distribution (Bragg peak characterized by a sharp distal and lateral penumbra) compared with conventional photon-based radiation therapy (X-ray). These ballistic advantages apply to the treatment of deep-sited tumours located close to critical structures and requiring high-dose levels. [60–250 MeV] proton-beam therapy is now widely accepted as the “gold standard” in specific indications in adults – ocular melanoma, chordoma and chondrosarcoma of the base of skull – and is regarded as a highly promising treatment modality in the treatment of paediatric malignancies (brain tumours, sarcomas…). This includes the relative sparing of surrounding normal organs from low and mid-doses that can cause deleterious side-effects such as radiation-induced secondary malignancies. Other clinical studies are currently testing proton beam in dose-escalation evaluations, in prostate, lung, hepatocellular cancers, etc. Clinical validation of these new indications appears necessary. To date, over 60,000 patients worldwide have received part or all of their radiation therapy program by proton beams, in approximately 30 treatment facilities.  相似文献   
53.
OBJECTIVES: To gain more knowledge of changes in main pulmonary artery flow and right ventricular mass and volumes in patients with pulmonary hypertension during epoprostenol therapy. METHODS: Eleven patients (9 women) were evaluated before the start of therapy and every 4 months thereafter. Right and left ventricular volumes and masses were measured by cine MRI. Flow was measured with MRI velocity quantification. At the same times, 6-min walking tests were performed. Right-heart catheterizations were performed at baseline and after 1 year. RESULTS: Right ventricular mass in the patient group was significantly higher from that in a control group of healthy volunteers (95 +/- 26 g vs 42 +/- 10 g, p < 0.05 [mean +/- SD]), whereas the stroke volume was lower (34 +/- 11 mL vs 81 +/- 11 mL, p < 0.05). The greatest improvement in right ventricular stroke volume (to 41 +/- 11 mL, p < 0.05) took place in the first 4 months. During the 1-year follow-up, right ventricular end-diastolic volume and mass did not change, and mean pulmonary artery pressure remained nearly stable at 55 mm Hg at baseline and 53 mm Hg after 1 year. Pulmonary vascular resistance decreased by 12.5% (p = 0.06). CONCLUSIONS: From these data we conclude that epoprostenol lowers pulmonary vascular resistance, leading to an increase in pulmonary artery flow. This increase in pulmonary artery flow corresponds well with the increase in 6-min walking distance and can be noninvasively monitored by MRI (flow quantification). Right ventricular dilatation and hypertrophy are not reversed by epoprostenol therapy, but do not progress either.  相似文献   
54.
Adequacy of bone marrow trephine biopsy specimens in children.   总被引:3,自引:3,他引:0       下载免费PDF全文
AIMS: To evaluate success in obtaining adequate bone marrow trephine biopsy cores from children. METHODS: Sections of trephine biopsy cores submitted by 25 centres from children with neuroblastoma over a five year period were reviewed centrally. In cores containing no tumour adequacy was defined as 0.5 cm of well preserved bone marrow after processing. Occasional smaller cores containing obvious tumour were also considered adequate. RESULTS: Of 822 biopsy specimens, 139 (17%) were inadequate. In 13 centres submitting at least 20 cores failure rates ranged from 2.6 to 50%. There was no improvement over the five years of the study. There was no practically important correlation between the numbers of cores submitted and success in obtaining adequate specimens. Although a lower rate of inadequate biopsy specimens was found when haematologists rather than paediatricians (13 v 29%) were the predominant operators this should not be overinterpreted, not least because of the potentially confounding association between haematologist operators and larger numbers of biopsy specimens, and because the arbitrary subdivision of centres according to operator specialty was crude. The skill of individual operators could not be assessed. CONCLUSIONS: Many operators do not obtain adequate bone marrow biopsy specimens from children. Improvement is necessary because this is an invasive investigation, often performed under general anaesthesia. Reporting pathologists are well placed to influence practice by pointing out inadequacies in the specimen and suggesting retraining or even a change in operator. Improvement would almost certainly occur if this investigation was restricted to locally recognised successful operators, whatever their specialty. Most centres should review their practice and devise strategies to improve their ability to obtain adequate cores.  相似文献   
55.
A case of mastocytosis of the bone associated with urticaria pigmentosa was first suspected of being a generalized metastatic malignancy, for the radiographic manifestations were not connected by us with the patient's skin disease. The histologic diagnosis of systemic mastocytosis was also missed primarily, because mast cells are not visualized in the conventional hematoxylin and eosin staining of the histologic sections. Special stainings revealed mastocytosis. Irregular remodeling of the bone was also seen, which was consistent with the radiographically irregular bone structure.  相似文献   
56.
PROBLEM: Complement lytic activity has been demonstrated, and a potential for its activation is present in human colostrum and milk. This necessitates the presence of regulatory mechanisms protecting epithelial cells in the oropharynx and the gastrointestinal tract of the infant, the milk cellular elements, and bacteria colonizing the oropharynx and the gastrointestinal tract. Lactoferrin and C1 inhibitor have been attributed such a role. However, it is likely that additional protection against the cytolytic activity of the membrane attack complex is required. This has lead us to investigate the presence of the complement regulatory protein CD59 in human colostrum and milk, and to further characterize the source of secretion. METHOD: Samples of human colostrum and milk were obtained from volunteers at different stages of lactation, and separated into fat, skim milk, and milk cellular elements by centrifugation. Normal human mammary gland tissues were obtained from patients undergoing biopsy for benign conditions. SDS-PAGE and Western blotting, and an immuno dot-blot assay were used to identify CD59 in human milk. Immunohistochemistry was performed on all tissue samples and cytospins of the milk cellular elements, using monoclonal antibodies to CD59. RESULTS: CD59 was present in cell-free colostrum and milk as a 19–25 kDa glycoprotein. No variation in CD59 levels was detected between colostrum and milk. CD59 was present in great amounts in the cytoplasm and was highly expressed on the surface membrane on mammary gland acinar and ductal epithelial cells, while the milk cellular elements contained CD59 mainly in their cytoplasm. CONCLUSION: The complement regulatory protein CD59 present in cell-free human colostrum and milk may exert its effects both in the mammary gland and in the oropharynx and gastrointestinal tract of the infant. The lobuloalveolar epithelial cells in the mammary gland are the likely source of secretion.  相似文献   
57.
Generation of the Brucella melitensis ORFeome Version 1.1   总被引:1,自引:0,他引:1       下载免费PDF全文
The bacteria of the Brucella genus are responsible for a worldwide zoonosis called brucellosis. They belong to the α-proteobacteria group, as many other bacteria that live in close association with a eukaryotic host. Importantly, the Brucellae are mainly intracellular pathogens, and the molecular mechanisms of their virulence are still poorly understood. Using the complete genome sequence of Brucella melitensis, we generated a database of protein-coding open reading frames (ORFs) and constructed an ORFeome library of 3091 Gateway Entry clones, each containing a defined ORF. This first version of the Brucella ORFeome (v1.1) provides the coding sequences in a user-friendly format amenable to high-throughput functional genomic and proteomic experiments, as the ORFs are conveniently transferable from the Entry clones to various Expression vectors by recombinational cloning. The cloning of the Brucella ORFeome v1.1 should help to provide a better understanding of the molecular mechanisms of virulence, including the identification of bacterial protein-protein interactions, but also interactions between bacterial effectors and their host's targets.  相似文献   
58.
59.
Serum IgA, IgG and IgM concentrations were determined in 30 patients with partial epilepsy before and during carbamazepine therapy. None of them had received anti-epileptic drugs prior to the study. The IgA and IgM concentrations decreased significantly during the 1st month of treatment ( P < 0.0001). No further decrease was observed during the subsequent 3 months. 15 patients were followed for 8-30 months. The IgA concentrations remained low, while the IgM concentrations tended to increase. However, the IgM concentrations did not reach the levels which were found before carbamazepine was started. Carbamazepine had no influence on the mean IgG serum concentration. There was no relationship between the IgA and IgM concentrations in serum and the serum concentrations of carbamazepine.  相似文献   
60.
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