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111.
The ability to acquire a motor and cognitive skill was investigated in 26 patients with schizophrenia and 26 normal participants using repeated testing on the Tower of Toronto puzzle. Seven patients with defective performance were retested using additional trials and immediate feedback designed to facilitate problem solving. A component analysis of performance was used based on J. R. Anderson's (1987) model of cognitive skill learning. Patients exhibited a performance deficit on both motor and cognitive skills. However, their acquisition rate was similar to that of normal participants on most parameters, indicating that skill learning suffered little or no impairment. Performance deficit was accounted for by poor problem-solving ability, explicit memory, and general intellectual capacities. It was remediable in some, but not all, patients. Remediation failure was also related to severe defects of cognitive functions.  相似文献   
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OBJECTIVES: To design a questionnaire for the identification and assessment of severity of back pain for epidemiological purposes, and gain preliminary experience of its use. METHODS: A group of specialists, experienced in the epidemiology and clinical assessment of back pain, designed the questionnaire, and tested it individually. It was also given cross sectionally by interview to a population of male coal mine workers. RESULTS: The questionnaire comprised a maximum of 12 questions on the presence, radiation, frequency, and severity of back pain with reference to difficulty with specific activities, interference with normal work, and absence from work. 471 coal miners answered the questionnaire (66% of those invited). 56% (265 men) of the responders reported pain or ache in the back during the previous 12 months, and the incidence of first ever attacks during the same period was reported to be 34%. 69% reported having had back pain at some time. The responses to the questionnaire were partially validated by comparison with certified sickness absence for two days or more attributed to back pain. In men who were symptomatic in the previous 12 months, for the question relating to absence from work because of back pain, the sensitivity was 82% and specificity was 84%. CONCLUSION: The questionnaire is easy to administer and generates clear cut data that could be useful for epidemiological or screening purposes. Preliminary, limited, studies of its validity are reasonably encouraging, although further validation is required. It is hoped that researchers will find the questionnaire useful, will extend its validation, and continue to develop it.  相似文献   
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We have examined the prothrombin gene as a candidate gene for venous thrombosis in selected patients with a documented familial history of venous thrombophilia. All the exons and the 5'- and 3'-UT region of the prothrombin gene were analyzed by polymerase chain reaction and direct sequencing in 28 probands. Except for known polymorphic sites, no deviations were found in the coding regions and the 5'-UT region. Only one nucleotide change (a G to A transition) at position 20210 was identified in the sequence of the 3'-UT region. Eighteen percent of the patients had the 20210 AG genotype, as compared with 1% of a group of healthy controls (100 subjects). In a population-based case-control study, the 20210 A allele was identified as a common allele (allele frequency, 1.2%; 95% confidence interval, 0.5% to 1.8%), which increased the risk of venous thrombosis almost threefold {odds ratio, 2.8; 95% confidence interval, 1.4 to 5.6}. The risk of thrombosis increased for all ages and both sexes. An association was found between the presence of the 20210 A allele and elevated prothrombin levels. Most individuals (87%) with the 20210 A allele are in the highest quartile of plasma prothrombin levels (> 1.15 U/mL). Elevated prothrombin itself also was found to be a risk factor for venous thrombosis.  相似文献   
116.
Chronic nonspherocytic hemolytic anemia has been observed in a recently described glucose-6-phosphate dehydrogenase (G6PD) variant, G6PDWayne. The mechanical properties of these erythrocytes and other G6PD variants were examined. The deformability of G6PD-deficient erythrocytes was normal, as determined by osmotic scan ektacytometry, and was not significantly affected by hemolytic crisis. In the common varieties of G6PD deficiency, the mechanical stability of the red blood cell (RBC) membrane was greater than normal, but G6PDWayne membranes were abnormally susceptible to shear-induced fragmentation. There was no evidence for a concurrent genetic defect in spectrin, because self-association constants and tryptic digests were normal. The fragility of G6PDWayne membranes appeared to be a consequence of oxidative damage to membrane thiol groups associated with a low glutathione (GSH) level in these RBCs. Associations among GSH level, thiol oxidation, and membrane instability were also found when a larger group of G6PD-deficient RBCs were examined. In normal erythrocytes, 1-chloro-2,4-dinitrobenzene was used to reduce GSH levels by 50%. Membrane thiol oxidation and membrane fragility both increased when these cells were kept at 4 degrees C for 3 to 5 days. Our findings suggest that chronic depletion of GSH leads to the destabilization of membrane skeleton through oxidation of membrane protein thiols.  相似文献   
117.
Three months after the launch of the MMR programme in the United Kingdom and the Republic of Ireland, a postal questionnaire was sent to all GP scheme trainees in both Northern Ireland and the Republic of Ireland. The response rate was 81%. All trainees were enthusiastic about promoting MMR immunisation; with 27% favouring compulsory immunisation. 9% had never seen a patient with measles. This did not alter their attitude towards the beneficial effects of MMR immunisation. Of pre-practice year trainees 26% felt their level of knowledge of immunisation was inadequate, 59% claimed to have received no education on immunisation during their vocational training to date. This may reflects deficiencies in their medical curriculum to-date. 95% of third-year trainees indicated that their practice experience had been the source of at least some of their education on immunisation. Only 46% of trainees in the Republic of Ireland were aware of their Department of Health's aims in launching the MMR immunisation campaign.  相似文献   
118.
OBJECTIVE: To determine the results peranal excision for rectal carcinoma. DESIGN: Retrospective case series. SETTING: A university-affiliated hospital. PATIENTS: Of 178 patients who presented for curative resection of rectal carcinoma between 1975 and 1993, 19 (10.7%) were deemed suitable for local excision. There were 10 men and 9 women with a mean age of 71.2 years. The follow-up ranged from 13 to 184 months. INTERVENTION: Peranal excision. MAIN OUTCOME MEASURES: Histologic differentiation, gross morphology, depth of invasion and size of the carcinoma, adequacy of margins of excision, complications of operation, rates of recurrence, results of salvage therapy and 5-year survival. RESULTS: There were no intraoperative complications. Postoperative complications included urinary retention (one patient) and bleeding (one patient). There were five local recurrences (26%). Salvage operations were performed in three (60%) patients and were successful in two of them. The 5-year cancer-specific survival rate was 82%. The recurrence rate was higher in patients with inadequate margins of excision and ulcerative lesions. Neither size nor grade of the carcinoma correlated with recurrence. CONCLUSIONS: Local excision of rectal carcinoma can be performed successfully in selected patients. Diligent follow-up is required, because up to 60% of local recurrences can be treated successfully.  相似文献   
119.
Human infection with a zoonotic Brugia species in the United States is uncommon. Positive identification of the filarial nematode is required for histopathologic diagnosis. Many cases may go unrecognized because of the nonspecific clinical manifestations and the nondiagnostic histologic changes occurring in involved lymph nodes. A case of zoonotic Brugia lymphadenitis is described in a patient from Rhode Island, in which a small nongravid female worm was identified in a lymph node biopsy specimen. The lymph node also showed a spectrum of reaction changes including the presence of florid monocytoid B-cell proliferation, which has not been described in association with zoonotic Brugian filariasis.  相似文献   
120.
Forty-four goats were milked and milk flow recorded without or with 1 min manual prestimulation in early, mid and late lactation. Ultrasound measurements of cross sections of the whole mammary gland were performed in a water bath. In additional experiments with 15 goats, milk flow was recorded and frequent blood samples were taken for the determination of oxytocin and prolactin concentrations. Milk yield increased from the first to the third lactation and decreased markedly during the course of lactation. Average and peak milk flow rates were closely related to the actual milk yield. The ultrasound cisternal area was 27.4 +/- 1.5% of the entire udder half cross section. Milking characteristics were scarcely different without or with prestimulation, although oxytocin was released within 30 s after the start of prestimulation, whereas oxytocin concentrations without prestimulation increased only after the start of milking. Concentrations of prolactin were higher during July and August than in April, and increased similarly with or without prestimulation during milking. In contrast to dairy cows, prestimulation and an opportune release of oxytocin during milking does not significantly influence the course of milk flow in goats, and this is probably because large amounts of cisternal milk allow milk ejection to be induced only after the start of milking without causing bimodal or otherwise reduced milk flow.  相似文献   
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