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31.
The controlled treatment outcome studies that examined the efficacy of EMDR in the treatment of posttraumatic stress disorder have yielded a range of results, with the efficacy of EMDR varying across studies. The current study sought to determine if differences in outcome were related to methodological differences. The research was reviewed to identify methodological strengths, weaknesses, and empirical findings. The relationships between effect size and methodology ratings were examined, using the Gold Standard (GS) Scale (adapted from Foa & Meadows, 1997). Results indicated a significant relationship between scores on the GS Scale and effect size, with more rigorous studies according to the GS Scale reporting larger effect sizes. There was also a significant correlation between effect size and treatment fidelity. Additional methodological components not detected by the GS Scale were identified, and suggestions were made for a Revised GS Scale. We conclude by noting that methodological rigor removes noise and thereby decreases error measurement, allowing for the more accurate detection of true treatment effects in EMDR studies. 相似文献
32.
S Dimauro C T Moraes S Shanske A Lombes H Nakase S Mita H J Tritschler E Bonilla A F Miranda E A Schon 《Revue neurologique》1991,147(6-7):443-449
Thanks to recent advances in the molecular genetics of mitochondrial encephalomyopathies, we can now begin to correlate genetic lesions with biochemical defects. In the fatal infantile myopathy due to cytochrome c oxidase (COX) deficiency, an autosomal recessive condition, immunocytochemical studies have shown an isolated defect of subunit VIIa, which is 1 of the only 2 tissue-specific subunits of human COX. In muscle biopsies from patients with Kearns-Sayre syndrome, a multisystem disorder characterized by deletions of the mitochondrial DNA (mtDNA), the activities of all mitochondrial enzymes containing mtDNA-encoded subunits are decreased. The results of Northern analysis, in situ hybridization, and immunocytochemistry in muscle, and of mitochondrial protein synthesis in cultured fibroblasts suggest that partially deleted mtDNAs are transcribed but not translated, probably due to lack of indispensable tRNAs. 相似文献
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35.
Manifestations of insulin-dependent diabetes mellitus in the periodontium of young Brazilian patients 总被引:1,自引:0,他引:1
The periodontal condition of patients with insulin-dependent diabetes mellitus was evaluated in terms of plaque, gingival indices, pocket depth, and alveolar bone loss. Thirty male and female diabetic patients aged 5 to 18 years were compared with 30 non-diabetic subjects and correlated with sex and age. Statistical analyses of the data showed that the mean plaque index was significantly higher (P less than 0.01) among the diabetic patients (1.23) than among the control subjects (0.81). The plaque index was significantly higher (P less than 0.01) among diabetic females (1.34) than among diabetic males (1.10), whereas no sex differences were observed in the control group. The arithmetic means obtained for gingival index were statistically higher (P less than 0.01) for the diabetics (0.58) when compared with the controls (0.15), but no significant differences were obtained when the values were correlated with sex and age. Pocket depth did not differ statistically between groups. When pocket depth was correlated with sex, a statistically significant difference (P less than 0.05) was observed only for the palatal region, with a depth of 2.1 mm in female patients and 1.92 mm in male patients. When pocket depth was correlated with age, a positive correlation (P less than 0.01) was detected in the diabetic group for all regions investigated, whereas the correlation was not significant in the control group. Mean alveolar bone loss was higher in the anterior upper (1.94 mm) and anterior lower (1.87 mm) regions of the diabetic group when compared to the controls (1.52 and 1.37 mm respectively), the difference being significant at the 5% level of probability.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
36.
Mitochondrial myopathy of childhood associated with depletion of mitochondrial DNA. 总被引:12,自引:0,他引:12
H J Tritschler F Andreetta C T Moraes E Bonilla E Arnaudo M J Danon S Glass B M Zelaya E Vamos N Telerman-Toppet 《Neurology》1992,42(1):209-217
We have studied five children with mitochondrial myopathy manifesting within or soon after the first year of life. Muscle biopsies showed ragged-red fibers and decreased respiratory chain activity. All five patients had a severe decrease (2 to 34% of normal) in the amount of muscle mitochondrial DNA (mtDNA). The depletion of mtDNA correlated with absence of mtDNA-encoded translation products and with loss of cytochrome c oxidase enzyme activity in individual muscle fibers. This mitochondrial myopathy of childhood illustrates one phenotypic expression of a novel pathogenetic mechanism in mitochondrial diseases, the specific depletion of mtDNA in affected tissues. 相似文献
37.
Louise Nadon Jack Siemiatycki Ron Dewar Daniel Krewski Michel Grin 《American journal of industrial medicine》1995,28(3):303-324
Polycyclic aromatic hydrocarbons (PAHs) demonstrate carcinogenic activity in animal models. Although some epidemiologic studies have implicated PAHs as risk factors for human cancer, the evidence reported to date has not been consistent. The purpose of this report is to describe the associations between occupational exposure to PAHs in the workplace and each of 14 types of cancer. A population-based, case-control study was carried out in Montreal to investigate associations between a large variety of environmental and occupational exposures on the one hand, and several types of cancer on the other. A detailed job history was obtained from each subject along with information on a number of potential confounders. Each job history was reviewed by a team of experts, who used this information to construct a corresponding history of occupational exposures. Among the PAH exposures considered were benzo(a)pyrene (B(a)P) and five categories of PAHs defined on the basis of the source material, namely, wood, petroleum, coal, other sources, and any source. Altogether, 3,730 cancer patients and 533 population controls were interviewed and their job exposure histories coded. For each of 14 types of cancer analyzed, three control groups were available: other cancer patients, population controls, and the pooled set of cancer and population controls. The associations between 14 cancer types and 6 PAH exposures were analyzed using logistic regression methods. For most types of cancer evaluated, there was no evidence of excess risk due to PAHs at the levels encountered in the occupations in which PAH exposure has been prevalent in the Montreal area. For a few cancer sites–the esophagus, the pancreas, and the prostate gland–there were suggestions of excess risk; these observations are noteworthy hypotheses for further investigation. For lung cancer, there appeared to be an increased risk due to PAHs among nonsmokers and light smokers, but not among heavy smokers. 相似文献
38.
David F Kroon M Louise Lawson Craig S Derkay Karen Hoffmann Joe McCook 《Otolaryngology--head and neck surgery》2002,126(5):499-504
OBJECTIVE: The study goal was to demonstrate the prevalence and severity of external auditory exostoses (EAEs) in a population of surfers and to examine the relationship between these lesions and the length of time surfed as well as water temperature in which the swimmers surfed. It was hypothesized that subjects who predominantly surfed in colder waters had more frequent and more severe exostoses. METHODS: Two hundred two avid surfers (91% male and 9% female, median age 17 years) were included in the study. EAEs were graded based on the extent of external auditory canal patency; grades of normal (100% patency), mild (66% to 99% patency), and moderate-severe (<66% patency) were assigned. Otoscopic findings were correlated with data collected via questionnaires that detailed surfing habits. RESULTS: There was a 38% overall prevalence of EAEs, with 69% of lesions graded as mild and 31% graded as moderate-severe. Professional surfers (odds ratio 3.8) and those subjects who surfed predominantly in colder waters (odds ratio 5.8) were found to be at a significantly increased risk for the development of EAEs. The number of years surfed was also found to be significant, increasing one's risk for developing an exostosis by 12% per year and for developing more severe lesions by 10% per year. Individuals who had moderate-severe EAEs were significantly more likely to be willing to surf in colder waters than were those who had mild EAEs (odds ratio 4.3). CONCLUSIONS: EAEs are more prevalent in cold water surfers, and additional years surfing increase one's risk not only for developing an EAE but also for developing more severe lesions. 相似文献
39.
Primary care referrals for lumbar spine radiography: diagnostic yield and clinical guidelines.
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William Hollingworth Christopher J Todd Hugh King Tony Males Adrian K Dixon Kanti R Karia Ann Louise Kinmonth 《The British journal of general practice》2002,52(479):475-480
BACKGROUND: Primary care requests for radiographs of the lumbar spine have come under increasing scrutiny. Guidelines aiming to reduce unnecessary radiographs by limiting referrals to patients at high risk of serious disease have been widely distributed. Trial evidence suggests that guidelines can reduce radiography referrals. It is not clear whether this reduction has been achieved in routine practice. AIM: This study, using routine data, was conducted to measure trends in pnmary care referrals for lumbar spine radiography at two hospitals between 1994 and 1999. DESIGN OF STUDY: Analysis of primary care requests for lumbar spine radiography from computerised records. SETTING: Addenbrooke's Hospital, Cambridge (1 July 1994 to 30 June 1999), and Ipswich General Hospital (1 July 1995 to 30 June 1999), United Kingdom. METHOD: All primary care requests for lumbar radiography were identified electronically from computerised information systems. A random sample of 2100 radiography reports were classified according to clinical importance. These classifications were used to examine whether the proportion of radiographs demonstrating potentially more serious findings had increased between 1994 and 1999. RESULTS: There was no evidence that primary care referrals for radiography of the lumbar spine had decreased between 1994 and 1999 at either hospital. General practitioners did not progressively refer more high-risk patients for lumbar radiography. Only a small proportion of patients had important radiographic findings that might warrant specialist referral or specific therapy. CONCLUSION: The implementation of diagnostic guidelines offers much to the NHS. However in these two hospitals, the reduction in radiograph utilisation evident in trials was not achieved. Guideline development is a resource intensive process; distribution must be supported by more effective implementation strategies. 相似文献
40.
Alister Oliver Mark Wright Andrew Matson Graham Woodrow Neil King Louise Dye 《Nephrology, dialysis, transplantation》2004,19(11):2883-2885
BACKGROUND: Interdialytic weight gain (IDWG) can be reduced by lowering the dialysate sodium concentration ([Na]) in haemodialysis patients. It has been assumed that this is because thirst is reduced, although this has been difficult to prove. We compared thirst patterns in stable haemodialysis patients with high and low IDWG using a novel technique and compared the effect of low sodium dialysis (LSD) with normal sodium dialysis (NSD). METHODS: Eight patients with initial high IDWG and seven with low IDWG completed hourly visual analogue ratings of thirst using a modified palmtop computer during the dialysis day and the interdialytic day. The dialysate [Na] was progressively reduced by up to 5 mmol/l over five treatments. Dialysis continued at the lowest attained [Na] for 2 weeks and the measurements were repeated. The dialysate [Na] then returned to baseline and the process was repeated. RESULTS: Baseline interdialytic day mean thirst was higher than the dialysis day mean for the high IDWG group (49.9+/-14.0 vs 36.2+/-16.6) and higher than the low weight gain group (49.9+/-14.0 vs 34.1+/-14.6). This trend persisted on LSD, but there was a pronounced increase in post-dialysis thirst scores for both groups (high IDWG: 46+/-13 vs 30+/-21; low IDWG: 48+/-24 vs 33+/-18). The high IDWG group demonstrated lower IDWG during LSD than NSD (2.23+/-0.98 vs 2.86+/-0.38 kg; P<0.05). CONCLUSIONS: Our results indicate that patients with high IDWG experience more intense feelings of thirst on the interdialytic day. LSD reduces their IDWG, but paradoxically increases thirst in the immediate post-dialysis period. 相似文献