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31.
Gene therapy may be an important adjuvant for treating cancer in the pleural space. The initial results of retroviral gene transfer to cancer cells in malignant pleural effusions revealed that transduction was markedly inhibited, and studies to characterize the inhibitory factor(s) were performed. The inhibition was contained within the soluble, rather than cellular, components of the effusions and was demonstrated with amphotropic, gibbon ape leukemia virus, and vesicular stomatitis virus-glycoprotein pseudotyped retroviral vectors. After excluding complement proteins, a series of studies identified chondroitin sulfates (CSs) as the inhibitory substances. First, treatment of the effusions with mammalian hyaluronidase or chondroitinases, but not Streptomyces hyaluronidase, abolished the inhibitory activity. Second, addition of exogenous CS glycosaminoglycans mimicked the inhibition observed with pleural effusions. Third, immunoassays and biochemical analyses of malignant pleural effusion specimens revealed CS in relevant concentrations within pleural fluid. Fourth, proteoglycans/glycosaminoglycans isolated from the effusions inhibited retroviral gene transfer. Analyses of the mechanism of inhibition indicate that the chondroitin sulfates interact with vector in solution rather than at the target cell surface. These results suggest that drainage of the malignant pleural effusion, and perhaps enzymatic pretreatment of the pleural cavity, will be necessary for efficient retroviral vector mediated gene delivery to pleural metastases.  相似文献   
32.
In 1989, Pacific Northwest National Laboratory developed a program, for the U.S. Department of Energy, to involve local citizens in environmental surveillance at the Hanford Site. The Community-Operated Environmental Surveillance Program was patterned after similar community-involvement efforts at the Nevada Test Site and the Three Mile Island nuclear facility. Its purpose is to increase the flow of information to the public, thereby enhancing the public's awareness and understanding of surveillance activities. The program consists of two components: radiological air monitoring at nine offsite locations and agricultural product sampling at selected locations near the site. At each air-monitoring station, two local school teachers collect air particulate samples and operate equipment to monitor ambient radiation levels. Atmospheric tritium samples (as water vapor) are also collected at some locations. Four of the air-monitoring stations include large, colorful informational displays for public viewing. These displays provide details on station equipment, sample types, and sampling purposes. Instruments in the displays also monitor, record, and show real-time ambient radiation readings (measured with a pressurized ionization chamber) and meteorological conditions. Agricultural products, grown primarily by middle-school-aged students, are obtained from areas downwind of the site. Following analysis of these samples, environmental surveillance staff visit the schools to discuss the results with the students and their teachers. The data collected by these air and agricultural sampling efforts are summarized with other routinely collected sitewide surveillance data and reported annually in the Hanford Site environmental report.  相似文献   
33.
In the last decade there was growing interest in strategic management literature about factors that influence a company's ability to use IT. There is general consensus that knowledge and competency are necessary in developing an IT capability, but there is very little understanding of what the necessary competencies are, and how they influence IS usage in different contexts. The small and medium-sized enterprise context is particularly interesting for two reasons: it constitutes a major part of the economy and it has been relatively unsuccessful in exploiting e-business.  相似文献   
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Two-hundred and one strains classified under the (Pasteurella) haemolytica-complex isolated from cattle, sheep, deer, pigs, hares and rabbits were investigated by ribotyping. Fifty-nine of these strains were selected for further studies using multilocus enzyme electrophoresis (MEE). A correlation between the clusters identified by ribotyping and MEE was demonstrated and the results furthermore indicated that a genetic basis exists for most clusters previously outlined by the use of quantitative evaluation of phenotypic data. The taxonomic relevance of ornithine decarboxylase and fermentation of L-arabinose, D-sorbitol and glucosides for taxonomic delineation within the (P.) haemolytica-complex was supported. A taxonomic importance was further indicated for ONPG, ONPX, ONPF, meso-inositol, D-xylose, maltose, dextrine and NPG in relation to some of the taxa. Within the porcine taxon 15, however, differences in ornithine decarboxylase did not correspond to genetic clusters. Six lineages were revealed by MEE. Lineage A contained electrophoretic types (ETs) representing biogroups 1, 3A-3H, 8A and 9, indicating a genetic relationship between these groups--an observation which was supported by ribotyping. Lineage B included biogroup 8D, 3 strains from biogroup 10 and a single strain from biogroup 1 and taxon 18/biovar 1. Lineage C contained strains allocated to biogroup 6 from ruminants and the porcine taxon 15. The similarity between these two groups was accentuated by ribotyping. Lineage D and the single isolate in lineage E contained strains allocated to biogroups 7, 10, 8B and 8C, in addition to single strains from biogroups 6 and 9. The same strains were found in the heterogenous ribotype cluster 17. Lineage F contained strains representing the leprine taxon 20 and the ruminant (P.) granulomatis. Ribotyping indicated that the ruminant biogroup 3J was affiliated with both taxon 20 and (P.) granulomatis.  相似文献   
36.
Trauma is the major source of mortality in the pediatric population. A retrospective review was performed on patients admitted to the Children's Hospital and Health Center Trauma Program, San Diego, California, from August 1984 to May 1990. The purpose of this review was to evaluate pediatric trauma and to determine the best treatment and evaluation for genitourinary injuries. Blunt trauma was responsible for 98 percent of the injuries, with renal injuries being the most common. Bladder (7) and male urethral (2) injuries, and vaginal lacerations (8) also occurred. The most severe renal injuries (70%) and all significant bladder and urethral injuries were associated with gross hematuria. Hypotension was present in 31 percent of patients but rarely required surgical exploration for correction. Eighty-six patients underwent radiographic imaging. Computerized tomography (CT) scans demonstrated the most information about intra-abdominal solid organ injuries but was inaccurate in detecting bladder or urethral injuries. Genitourinary injury is common in children but rarely requires surgical management. CT scan is the best study to determine extent of solid-organ injury but is inferior to cystourethrography to diagnose bladder or urethral injuries.  相似文献   
37.
The purpose of our study was to determine the prevalence of sleep related breathing disorders (SRBD) in patients with an implantable cardioverter-defibrillator (ICD) and to evaluate prospectively the possible influence of SRBD on arrhythmia recurrence and circadian arrhythmia variation as well as on cardiac mortality during long-term follow-up. Forty consecutive ICD recipients with cardiac disease and a documented history of spontaneous, life-threatening, ventricular tachyarrhythmias underwent full-night polysomnography and were followed for 2 years. In 16 of 40 patients (40%), SRBD were diagnosed (Apnea/Hypopnea Index (AHI) > 10); in 9 of these 16 patients (56%) central sleep apneas (CSA) occurred (in 8 of these 9 patients in combination with Cheyne-Stokes respiration). Seven of the 16 patients with SRBD (44%) revealed obstructive sleep apneas (OSA). AHI was 32 +/- 15 (12-60) in patients with CSA and 32 +/- 27 (11-86) in patients with OSA. Patients with and without SRBD were comparable concerning left ventricular ejection fraction, NYHA classification, cardiac disease, ICD indication, and concomitant medication. ICD registered ventricular tachyarrhythmias occurred in 10 of 24 patients (42%) without SRBD, in 4 of 9 patients (44%) with CSA, and in 3 of 7 patients (44%) with OSA. The numbers and circadian variation of episodes registered during follow-up in patients without SRBD, with OSA or CSA were comparable (14 +/- 25, median 4 vs 15 +/- 15, median 7 vs 4 +/- 5, median 2.5). The 2-year cardiac mortality was highest in patients with CSA (4/9 (44%) vs. 0/7 patients (0%) with OSA vs 3/24 patients (12.5%) without SRBD. Thus, the prevalence of SRBD in patients with chronic heart failure and a history of malignant ventricular tachyarrhythmias is high (40%) and the occurrence of CSA seems to be predictive for cardiac mortality in these patients. An influence of moderate SRBD on arrhythmia recurrence and circadian variation of spontaneous sustained tachyarrhythmic events could not be demonstrated.  相似文献   
38.
BACKGROUND: Epidemiologic data concerning skin diseases in many rural areas in sub-Saharan Africa are not available. Little is known about the effect of regular treatment schedules by paramedical staff (especially community health workers) in the primary healthcare system on the severity and prevalence of dermatoses. METHODS: 5780 school and pre-school children from 13 primary schools in four sublocations in rural western Kenya (Kisumu District) were examined for dermatoses by the author, together with community health workers in 1993. On-the-spot training and weekend seminars about important and common dermatoses were also given. In 1994 a dermatology program was started within the primary healthcare system. Twelve trained community health workers carried out regular school visits once a week and diagnosed and treated pupils with dermatoses. Treatment was performed with gentian violet 1% solution for bacterial skin infections, Whitfield's ointment for dermatophytoses, benzylbenzoate emulsion 25% for scabies, and hydrocortisone acetate 1% cream for eczemas. All schools were visited again in 1995 to evaluate the long-term effects of the program. RESULTS: In 1993, the prevalence rate for dermatoses was 32.4%. Most of the skin diseases found were of infective origin (27.1% were caused by bacteria, 21.6% by fungi, and 17.6% by arthropods, mainly scabies mites). Dermatitis accounted for 3.5%. In 1995, the prevalence of dermatoses declined to 29.6% (p<0.05), and this reduction was most strongly observed for tropical ulcers and tinea capitis. Additionally, there was an improvement in the extent and severity of skin diseases. CONCLUSIONS: This study defines, for the first time, the number and extent of skin diseases in children in rural Kisumu District; most dermatoses were of infective origin. The study demonstrates that community health workers in the primary healthcare system are capable of dealing successfully with the most common dermatoses in children following a short training period.  相似文献   
39.
GW Gynther  AB Holmlund 《Canadian Metallurgical Quarterly》1998,56(2):147-51; discussion 152
PURPOSE: This study evaluated the efficacy of arthroscopic lysis and lavage in patients with temporomandibular joint (TMJ) symptoms and generalized osteoarthritis (GOA) or rheumatoid arthritis (RA). PATIENTS AND METHODS: Twenty-three GOA patients and 23 RA patients were evaluated after 1 year. RESULTS: Seventeen of 23 patients (74%) in the RA group improved after arthroscopic lysis and lavages compared with 10 of 23 (43%) of the GOA patients. Lateral joint tenderness, crepitation, maximal opening, and maximal protrusion showed most improvement in the RA group. CONCLUSIONS: On the basis of this short-term follow-up study, arthroscopic lysis and lavage seem to provide an effective treatment for TMJ pain and dysfunction in RA patients but not in GOA patients.  相似文献   
40.
OBJECTIVE: The purpose of the field trials for oppositional defiant disorder and conduct disorder was to select valid diagnostic thresholds for these disorders and to compare the psychometric properties of DSM-IV criteria for oppositional defiant disorder and conduct disorder with previous DSM diagnostic formulations. METHOD: Structured diagnostic interviews, standardized clinician's validation diagnoses, and multiple measures of impairment were obtained for 440 clinic-referred children and adolescents aged 4-17 years. RESULTS: A diagnostic threshold of four symptoms of oppositional defiant disorder optimized identification of impaired children, improved agreement somewhat with the clinician's validation diagnosis, and had somewhat better test-retest agreement than DSM-III-R. In the case of conduct disorder, the optimal time window for ascertainment of symptoms was clarified. A diagnostic threshold of three symptoms of conduct disorder maximized accurate identification of impaired children and agreement with the clinician's validation diagnosis and resulted in slightly better test-retest agreement than DSM-III-R. Compared with the DSM-III-R definition, the DSM-IV definition of oppositional defiant disorder was somewhat more prevalent, but the prevalence of conduct disorder was essentially unchanged. CONCLUSIONS: DSM-IV definitions of oppositional defiant disorder and conduct disorder are somewhat better than DSM-III-R definitions in terms of internal consistency and test-retest agreement, and the validity of the DSM-IV definition of oppositional defiant disorder is slightly better than that of DSM-III-R.  相似文献   
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