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21.
Transplant pneumonectomy is a rarely performed procedure. It is occasionally carried out in the course of retransplantation. To our knowledge, resection of a transplanted lung without its replacement and with successful outcome in the adult has not been previously reported. We present a case of elective left transplant pneumonectomy in a 38-year-old man 6 years after left single-lung transplant. At 12 months after resection, the patient remains well, with good exercise tolerance.  相似文献   
22.
Paget's disease is a focal condition of bone. To study changes in cells within pagetic lesions, we cultured osteoblasts and stromal cells from 22 patients and compared gene expression in these cells to cells from healthy bone. We identified several differentially regulated genes, and we suggest that these changes could lead to the formation of the lesions. INTRODUCTION: Paget's disease is a focal condition of bone of unknown cause. Although it is regarded as primarily an osteoclast disorder, the tight coupling of the activity of osteoclasts and osteoblasts suggests that the osteoblast could play a key role in its pathogenesis. The aim of the study was to identify possible changes in pagetic osteoblasts and stromal cells that might contribute to the development of pagetic lesions. MATERIALS AND METHODS: Candidate genes were identified based on known bone cell regulators, supplemented with microarray analysis. Gene expression was determined by real-time PCR in primary cultures of osteoblasts and bone marrow stromal cells from pagetic patients and control subjects. Concentrations of secreted proteins were determined by ELISA. RESULTS: Dickkopf1 mRNA and protein levels were increased in both pagetic osteoblast and stromal cell cultures, and interleukin (IL)-1 and IL-6 were overexpressed in pagetic osteoblasts. These changes parallel recent findings in myeloma bone disease, which shares some clinical similarities with Paget's disease. Alkaline phosphatase was overexpressed, and bone sialoprotein and osteocalcin were underexpressed in pagetic osteoblasts, consistent with their circulating levels in pagetic patients. It is hypothesized that overexpression of Dickkopf1, IL-1, and IL-6 would result in stimulation of osteoclast proliferation and inhibition of osteoblast growth, leading to the development of the characteristic lytic bone lesions. By stimulating osteoblast differentiation, Dickkopf1 and IL-6 may also promote mineralization, leading to the conversion of lytic lesions to sclerotic. CONCLUSIONS: These findings suggest that dysregulated gene expression in pagetic osteoblasts could cause the changes in bone cell number and function characteristic of Paget's disease.  相似文献   
23.
股骨干骨折--逆行穿钉与顺行穿钉的探讨   总被引:1,自引:0,他引:1  
在对股骨骨折进行逆行和顺行置入髓内钉治疗时,两种治疗方法产生很高的愈合率和相近的畸形愈合率。虽然未经过一致的认定,但那些接受顺行穿钉治疗的患者愈合较快。患者在接受逆行穿钉治疗后膝关节疼痛频繁出现,然而髋关节疼痛和异位骨化现象却在接受顺行穿钉治疗的患者中存在。患其它并发症的几率也无显著增长。因此不能决定功能结果。  相似文献   
24.
Abstract: The evaluation of the Healthy Aboriginal Life Team's (HALT) petrol-sniffing prevention programs at Yuendumu, Kintore and the Pitjantjatjara Lands first required a specification of program outcome—which was not changes in the enumerated prevalence of petrol sniffing, but alteration in parental perceptions of the relevance and effectiveness of families' nurturant authority over recalcitrant youngsters. The evaluation then proceeded by a series of interviews with resident or ex-resident adults (Aboriginal and non-Aboriginal) of Yuendumu, Kintore, Kiwirrkurra, Ernabella, Indulkana and Fregon. Adults articulated their efficacy in different ways in each place. Some favoured the conclusion that HALT had helped them, others clearly identified HALT as an obstacle to or a distraction from the implementation of other preventive and curative community-based action. We discerned a ferment of cultural adjustment in the distribution of authority over children among parents and welfare agencies. We caution against finding in HALT'S successes a model procedure for benign interventions into such cultural adjustment.  相似文献   
25.
6-keto-prostaglandin F1a and thromboxane B2 were determined in order to obtain more information about the prostacyclin synthesis and thromboxane A2 release in 3- to 18-year-old healthy children and in offspring of parents who have had an acute myocardial infarction before the age of 45. The authors demonstrated a reduction of plasma prostacyclin synthesis in children with a positive family history of premature coronary arterial disease. Thromboxane levels in the affected adolescent boys were significantly lower compared with the controls. The ratio of thromboxane:prostacyclin in endangered children did not show a significant difference from that of healthy controls. These data indicate that prostaglandins are a definitive marker for identifying cardiovascular risk children. It must be supposed that in adolescence, only in boys, with a positive family history of premature coronary arterial disease, a compensatory mechanism exists to protect them from developing an imbalance in the regulation of prostaglandins.  相似文献   
26.
Comment     
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27.
Immunology     
A selection of interesting papers that were published in the two months before our press date in major journals most likely to report significant results in immunology.  相似文献   
28.
BACKGROUND: To adequately address the complex health needs of young people, their access to services, and the quality of services received, must be improved. AIMS: To explore the barriers to service provision for young people and to identify the training needs of primary healthcare service providers in New South Wales (NSW), Australia. DESIGN OF STUDY: A cross-sectional, qualitative study of the perspectives of a range of health service providers. SETTING: A range of primary healthcare organisations across NSW. METHODS: Samples of general practitioners (GPs), youth health workers, youth health coordinators, and community health centre staff were drawn from urban and rural clusters across NSW. Focus groups and interviews were used to identify barriers to service provision and the training needs of service providers. Data were tape recorded, transcribed, and analysed. RESULTS: Barriers to service provision among GPs and community health centre staff included inadequate time, flexibility, skills, and confidence in working with young people, and poor linkages with other relevant services. Training needs included better knowledge of and skills in adolescent health requirements, working with adolescents, and working with other services. Barriers to service provision for youth health workers and coordinators included lack of financial resources and infrastructure. There were few linkages between groups of service providers. CONCLUSION: Models of service provision that allow stronger linkages between service providers, sufficient time for consultation with young people, adequate training and support of health professionals, and flexibility of service provision, including outreach, should be explored and evaluated.  相似文献   
29.
1. The pharmacokinetics of Dalal-peptide T-NH2 (peptide T) was determined during phase I clinical trials in patients with acquired immunodeficiecy disease (AIDS) and AIDS related complex (ARC). Drug levels were determined by specific RIA, and in some cases with HPLC analysis, after intraveneous (i.v.) or intranasal (i.n.), via metered sprayer, administration.

2. The plasma kinetics appeared to be bi-phasic with a first compartment half-life of 30 to 60 minutes and a second plasma clearence rate of 4 to 6 hours, observed for both routes of administration. Peptide T, in one individual was confirmed to be present at 6 hrs in plasma, determined after HPLC isolation followed by specific RIA.

3. Bioavailabilty, determined for a 2 mg test dose in six individuals was 9.3 ± 6.9 nmol/L. Peak plasma levels of 41 ± 30 nmol/L after 10 mg i.n., 2.8 ± 5.9 nmol/L after 2mg i.n., and 0.13 ± 0.07 nmol/L after 0.4 mg i.n. were observed. In two individuals tested, peptide T was detected in CSF at levels 20% of the corresponding plasma level 90 and 145 minutes post i.v. administration. Peptide T was not detected in urine. I.N. administration was well tolerated for times up to 21 months.  相似文献   

30.
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