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21.
Backscatter imaging is useful for inspecting structures that are accessible only from one side. However, indications provided by scattered radiation are typically weak, convoluted and difficult to interpret. This paper explores the use of the coded aperture technique to detect flaws using gamma-ray backscatter imaging. The viability of this approach is demonstrated with indications obtained from Monte Carlo simulations of radiation scattering measurements. The results show that, with a 2 mm wide beam of 137Cs photons, flaws as small as 1.5 mm in width can be detected using this technique. Indications of changes in flaw size, location, multiplicity and density were also observable. In addition, it is possible to quantify, from the decoded indications, the flaw location and its size.  相似文献   
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The aims of this paper are to provide a brief overview of the types of education and training as well as a framework for co-occurring disorders courses at foundation and advanced levels. Mental health nurses encounter substance abuse problems as part of their workload and should be prepared adequately to work with individuals with the co-existence of mental health and substance abuse. However, co-occurring disorders are not often picked up by substance abuse or mental health services, indicating a need for improvement in ongoing professional development. The targeted audience for education and training in core competencies should be staff working in community mental health teams, inpatient services, assertive outreach teams, early intervention teams, crisis resolution teams, primary care, mental health services for older people, independent mental health projects, accommodation services, day care services, statutory drug and alcohol services, independent drug and alcohol service providers, and those working in hostel accommodations, housing, prison health care probation, and others in the criminal justice system. The theoretical and skills-based training will need to adopt a two-tiered approach as individuals working within mental health services will by definition need a higher emphasis on training around substance misuse and vice versa for individuals working in substance misuse services. One of the agenda items for interagency training is to challenge negative attitudes and prejudices around both mental health problems and substance misuse.  相似文献   
24.
Abstract: A child had cerebral palsy and linear and whorled nevoid hypermelanosis on the right side of his body. He had spasticity and wasting in both lower limbs, with electroencephalographic changes and brain abnormalities on computerized tomographic scan. Chromosomal study of peripheral blood leukocytes found a normal male karyotype. The pathogenesis of this condition is still unclear.  相似文献   
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OBJECTIVES: To audit the management of vascular trauma in Kuwait, 1992-2000. DESIGN: Retrospective open study. SETTING: Vascular surgery unit, teaching hospital, Kuwait. SUBJECTS: 155 patients with vascular injuries, most of which (n = 118) involved the extremities. 21 had neck injuries, 10 abdominal, and 6 chest. INTERVENTION: Revascularisation usually using the long saphenous vein in addition to direct repair or end-to-end anastomosis. MAIN OUTCOME: Morbidity (amputation) and mortality. RESULTS: Four lower limb grafts failed, two of which (2/69, 3%) required amputation. Overall, four patients died (3%), one of pulmonary embolism and 3 of severe injuries to major abdominal vessels. 3/10 patients with abdominal vascular trauma died. Mean (SD) follow up period was 4.4 (2) years. CONCLUSIONS: Civilian violence has increased in Kuwait. Vascular trauma to abdominal vessels is associated with high mortality. Autogenous saphenous vein forms an excellent conduit for revascularisation.  相似文献   
26.
The authors report the case of an ovarian teratoma infected by the eggs of the trematode Schistosoma haematobium. In consideration of the rare observation, bearing a paradigmatic value, they briefly discuss the particular tropism that the parasite demonstrated towards some tumoral structures and they also outline the immunological mechanisms activated by the Schistosoma.  相似文献   
27.
Background Alopecia is a common side-effect of cancer chemotherapy. Although this complication has been known for many decades, little progress has been made in its prevention or treatment. Previously, we made the following observations: ( a ) treatment of 8-day-old rats with 1-0-n-arabinofuranosylcytosine (ara-C), doxorubicin, and cyclophosphamide (CYC) produced either total body alopecia (ara-C and CYC) or alopecia confined to the head and proximal part of the neck (doxorubicin); ( b ) Imuvert, a biological response modifier, and interleukin-1 protected against alopecia-induced by ara-C; and (c) neither Imuvert or interleukin-1 protected against CYC-induced alopecia. Objective Experiments were designed to test for agents to protect against CYC-induced alopecia. Methods Agents were tested in the 8-day-old rats as a model for chemotherapy-induced alopecia. Results Mesna and S-2-(3-aminopropylamino)-ethylphospnorothioic acid (WR-2721) did not offer any protection against chemotherapy-induced alopecia. N-Acetylcysterine offered very good protection against alopecia induced by CYC but not that produced by ara-C in the newborn rate animal model. Conclusion N-Acetylcysteine may prove to be important in the prevention of CYC-induced alopecia, but this needs to be tested in the clinical setting.  相似文献   
28.
The widespread use and misuse of alcohol, drug and other psychoactive substances are major health and social concerns that affect the lives of many The social and health sequelae of psychoactive drugs and alcohol are preventable and manageable with minimal interventions Nurses and other health workers can effectively respond to substance misuse problems and their existing generic skills can be easily adapted in working with substance misusers This paper considers some of the issues such as the extent of the problem, attitudinal considerations, response to substance misusers and a brief outline of the role of the nurse The urgent need for education and training in substance misuse and addictive behaviour for nurse practitioners is also addressed  相似文献   
29.
Classical citrullinemia (CTLN1), a rare autosomal recessive disorder, is caused by mutations of the argininosuccinate synthetase (ASS) gene, localized on chromosome 9q34.1. ASS functions as a rate-limiting enzyme in the urea cycle. Previously, we identified 32 mutations in the ASS gene of CTLN1 patients mainly in Japan and the United States, and to date 34 different mutations have been described in 50 families worldwide. In the present study, we report ASS mutations detected in 35 additional CTLN1 families from 11 countries. By analyzing the entire coding sequence and the intron-exon boundaries of the ASS gene using RT-PCR and/or genomic DNA-PCR, we have identified 16 novel mutations (two different 1-bp deletions, a 67-bp insertion, and 13 missense) and have detected 12 known mutations. Altogether, 50 different mutations (seven deletion, three splice site, one duplication, two nonsense, and 37 missense) in 85 CTLN1 families were identified. On the basis of primary sequence comparisons with the crystal structure of E. coli ASS protein, it may be concluded that any of the 37 missense mutations found at 30 different positions led to structural and functional impairments of the human ASS protein. It has been found that three mutations are particularly frequent: IVS6-2A>G in 23 families (Japan: 20 and Korea: three), G390R in 18 families (Turkey: six, U.S.: five, Spain: three, Israel: one, Austria: one, Canada: one, and Bolivia: one), and R304W in 10 families (Japan: nine and Turkey: one). Most mutations of the ASS gene are "private" and are distributed throughout the gene, except for exons 5 and 12-14. It seems that the clinical course of the patients with truncated mutations or the G390R mutation is early-onset/severe. The phenotype of the patients with certain missense mutations (G362V or W179R) is more late-onset/mild. Eight patients with R86H, A118T, R265H, or K310R mutations were adult/late-onset and four of them showed severe symptoms during pregnancy or postpartum. However, it is still difficult to prove the genotype-phenotype correlation, because many patients were compound heterozygotes (with two different mutations), lived in different environments at the time of diagnosis, and/or had several treatment regimes or various knowledge of the disease.  相似文献   
30.
BACKGROUND: The diagnosis of hepatitis B virus (HBV) has until recently been based on traditional serologic methods targeting viral antigens and antibodies to viral proteins. The development of molecular methods allowing for the quantitation of HBV DNA is proving clinically valuable for monitoring therapy and detecting early treatment failures. OBJECTIVES: Here we report a new real-time (LightCycler) quantitative PCR for the detection of HBV DNA based on sequence specific hybridisation probes (designed in-house), targeting the HBV surface antigen. STUDY DESIGN: The assay was evaluated using a 10-fold dilution series of standard HBV DNA [Eurohep standard reference 1, genotype A, HBsAg subtype adw with a unitage of 10(6) WHO. i.u./ml] and 89 clinical serum samples. The performance was measured against a quantified standard HBV DNA working reagent (NIBSC code 98/780) and the sensitivity compared with our conventional thermal-block PCR. RESULTS AND CONCLUSION: Real-time PCR detected HBV DNA in 45% (40/89) and thermal-block PCR in 16% (14/75) of clinical samples. Results for 26 samples were below the detection limit of the thermal-block PCR but could be quantified by real-time (LightCycler) PCR. The LightCycler assay was at least 5 logs more sensitive than thermal-block PCR and could detect HBV in a linear range between 5 and 10(7) i.u. per reaction. The broad generic nature of the PCR primers coupled with the enhanced sensitivity and specificity of the fluorescent hybridisation probes makes this assay potentially valuable for both routine diagnostic and epidemiological work.  相似文献   
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