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81.
Deletions of chromosome 20q are associated with myeloid malignancies and have been previously shown to arise in a multipotent progenitor of both myeloid and B cells. However, B-cell differentiation from the abnormal progenitor was impaired. The CD40 antigen is a surface glycoprotein which is expressed in B cells and haemopoietic stem cells and is important for B-cell growth and development. Following the recent mapping of CD40 to chromosome 20q we sought to determine its position relative to 20q deletions. Analysis of lymphoblastoid cell lines carrying 20q deletions placed CD40 within a 19–21 cM interval which is almost coincidental with the common deleted region defined by previous analysis of patient samples. Our results raise the possibility that genetic alteration of this locus may contribute to the pathogenesis of myeloid disorders associated with 20q deletions.  相似文献   
82.
A series of 206 necropsies in Western Australia (WA) have had routine counts made of asbestos bodies in samples of lung tissue using conventional light microscopy. Thirty-two cases had worked in the asbestos industry at Wittenoom, WA and (log) counts of asbestos bodies in their lung tissue correlated well with estimates of their (log) cumulative airborne exposure to crocidolite fibers (r = 0.60). There was no association between the number of asbestos bodies and time since exposure to asbestos ceased. In subjects without known exposure to asbestos, there was a weak but nonsignificant increase in number of asbestos bodies with increasing age, with 26% of cases having no asbestos bodies present. It is concluded that the relatively simple technique of light microscopy for counting of asbestos bodies in lung tissue provides a reliable indication of the level of past occupational exposure to crocidolite in subjects whose exposure has been only to crocidolite. This could be extremely useful in follow-up studies of cohorts that lack reliable measures of airborne exposure to crocidolite asbestos.  相似文献   
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The abilities to control the voiding of the bladder and to act competently in dealing with fire are important factors of the normal development of children. Unfavourable conditional constellations in the socio-emotional, cognitive, or physical realm can cause developmental defects which manifest themselves in certain target symptoms, for instance Pyromania and Enuresis. The importance of multifactorial etiological models will be illustrated by a case report of a boy displaying symptoms of Pyromania and Enuresis nocturna. The analysis of the specific conditions of the case studied results in the appropriate multidimensional treatment concept.  相似文献   
85.
Aspects of peri-operative management, amputation level and rehabilitation of the lower limb amputee are reported in the context of a review of a rehabilitation service for amputees which includes an integrated prosthetic service. Two hundred admissions were reviewed and some complex cases described. It is concluded that: a very close liaison between the surgeon and the rehabilitation team (ideally with pre-operative consultation) is in the patient's best interests; any person previously walking (or a potential walker) should be considered for a trial of prosthetic walking; an integrated prosthetic service enhances the efficiency of the rehabilitation service; and that modification of the current Artificial Limb Scheme to allow manufacture of first definitive limbs in prosthetic rehabilitation units would further enhance service to patients.  相似文献   
86.
Background: Endothelium-derived nitric oxide causes vasodilation in part by increasing the dilator activity of other endothelium-derived mediators, including prostacyclin and a K sup +ATP channel-dependent hyperpolarizing factor. Although previous studies have proposed that isoflurane (ISO) depresses endothelium-dependent vasorelaxation by inhibiting endothelium-derived nitric oxide activity, the effects of ISO on the interactions among endothelium-derived dilators have not been characterized. The aim of this study was to determine the mechanisms underlying the inhibitory effect of ISO on endothelium-dependent relaxation in canine pulmonary arteries. Specifically, the goal was to assess the effects of ISO on the individual actions and on the synergistic interactions of these endothelium-derived mediators.

Methods: Canine pulmonary arterial rings were suspended for isometric tension recording. The effects of 1 minimum alveolar concentration ISO (0.4 mM) on vasorelaxation responses to bradykinin, A23187, acetylcholine, cromakalim, and SIN-1 were assessed in phenylephrine-precontracted rings with and without pretreatment with a nitric oxide synthase inhibitor (N sup omega -nitro-L-arginine methyl ester; L-NAME), a cyclooxygenase inhibitor (indomethacin), or a K sup +ATP, channel inhibitor (glybenclamide).

Results: Isofluane attenuated pulmonary vasorelaxation induced by bradykinin, A23187, and cromakalim but had no effect on relaxation induced by acetylcholine or SIN-1. Neither the nitric oxide-mediated nor the prostacyclin-mediated components of relaxation induced by bradykinin and A23187 were altered by ISO. However, ISO abolished the K sup +ATP -mediated component of relaxation and the K sup +ATP -dependent synergistic interaction between nitric oxide and prostacyclin.  相似文献   

87.
Although claims data are increasingly being used to measure and manage the cost and quality of health care, few studies have evaluated algorithms developed for such analyses. Therefore, the present study was performed to evaluate prospectively a previously published algorithm used to identify women with the new diagnosis of carcinoma of the breast. This algorithm had been developed from the patterns of claims that suggested common clinical presentations of carcinoma of the breast. In the present study, this algorithm was used to identify 177 potential cases of women with newly diagnosed carcinoma of the breast from the claims database of a large health maintenance organization (HMO). The algorithm's positive predictive value for cases identified in the present study was 83% (147/177). To attempt to improve upon the positive predictive value, multiple modifications of the algorithm were performed. The previously defined best modification of the initial algorithm yielded a positive predictive value of 84% (147/174) in the present study with the loss of none of the true positive cases. These results demonstrate that logic-based algorithms can be used as a valid and efficient method of identifying large numbers of new breast cancer cases from claims data. This algorithm provides a powerful tool to perform health care analysis and research for women with newly diagnosed carcinoma of the breast.  相似文献   
88.
Cis-dichlorodiamineplatinum(II) (cis-DDP) was encapsulated in reverse phase evaporation vesicles (REV, 0.6 mg cis-DDP/ml lipid solution) and multilayered liposomes (MLV, 0.3 mg cis-DDP/ml lipid solution) with different cholesterol content. The identity of cis-DDP in free and encapsulated form was checked by various techniques. Particle size, homogeneity of liposomes and distribution of cis-DDP in REVs were shown by electron microscopy. The examination of entrapped cis-DDP in REVs relating to buffer and serum stability, in vitro and in vivo antitumour activity and nephrotoxicity proved that all points are strongly influenced by the cholesterol (CH) content. Enclosed cis-DDP in phosphatidyl (PC)-REV has the same, and in PC: CH-REV, a lower effect in vitro and in vivo compared to treatment with the free drug. Irrespective of the application of tumour cells and substance (i.v., i.p.) in optimal therapeutic doses, an equal increase in life-span (ILS) was registered with the free drug and with PC-cis-DDP-REV, while cis-DDP in PC: CH-REV had a significantly reduced effectiveness. Liposomal encapsulation of cis-DDP also influenced body weight change and leucocyte counts. The blood urea nitrogen (BUN) level, as an indicator of renal toxicity, was only moderately increased after very high doses of cis-DDP (24 mg/kg) in PC: CH-REV.  相似文献   
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