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61.
Increased placental apoptosis in intrauterine growth restriction   总被引:2,自引:0,他引:2  
OBJECTIVES: Our purpose was to investigate a possible role for apoptosis in the pathophysiologic mechanisms of intrauterine growth restriction. STUDY DESIGN: Placental samples were obtained from 43 uncomplicated third-trimester pregnancies and from 26 pregnancies complicated by intrauterine growth restriction. The definition used to identify cases of intrauterine growth restriction depended on three criteria: clinical evidence of suboptimal growth, ultrasonographic evidence of deviation from an appropriate growth percentile, and individualized birth weight ratios <10th percentile. Light microscopy was used to quantify the incidence of apoptosis. Electron microscopy and TUNEL (terminal deoxynucleotidyl transferase–mediated deoxyuridine triphosphate nick end labeling) staining were used to confirm the occurrence of apoptosis. RESULTS: Quantification of apoptosis (medians and interquartile ranges) resulted in the following values: normal third trimester (n = 43) 0.14% of cells (0.08% to 0.20%) and intrauterine growth restriction third trimester (n  = 26) 0.24% of cells (0.16% to 0.29%). The incidence of apoptosis was significantly higher in placentas from pregnancies with intrauterine growth restriction compared with normal third-trimester placentas (p < 0.01, Mann Whitney U test). CONCLUSIONS: These results suggest that apoptosis may play a role in the pathophysiologic mechanisms of intrauterine growth restriction.(Am J Obstet Gynecol 1997;177:401)  相似文献   
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Exophthalmometry, the quantitative assessment of the position of the globe in the orbit, is a clinically useful measurement. The purpose of this study was to examine the performance of a simple exophthal-mometer that would lend itself to accurate and convenient use in clinical practice. In this study, two observers independently performed exophthalmometry on 100 eyes using the Hertel and Luedde instruments. The results were compared between instruments and between observers. There was no statistically or clinically significant difference between measurements taken with the Luedde as compared with the Hertel instrument. The Luedde exophthal-mometer has a number of advantages over the Hertel exophthalmometer, and represents a simple, inexpensive and equally reliable means of evaluating clinically the anteroposterior position of the eye in the orbit.  相似文献   
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A TEN-YEAR HOSPITAL SURVEY OF EYELID CANCER   总被引:1,自引:0,他引:1  
Two hundred and four cases of malignant eyelid tumours, managed at the Concord Hospital, were reviewed. These cases spanned a ten-year period between 1973 and 1982 and all were treated surgically. The nature of each tumour was confirmed by histopathological examination. Included in this review were the site of the tumour, the tumour pathology, the surgical management, the type of surgeon involved, the ocular complications, the management of recurrences and any mortality. The importance of preventing recurrences by adequate initial surgery with frozen section control is emphasized.  相似文献   
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To the Editor: There are a large number of studies addressing the impact of continuing medical education (Davis et al. 1995) and clinical guidelines (Grimshaw & Russell 1993) on changing clinical practice, but comparatively little on the impact of purchasers of health care. There is some evidence that financial incentives and penalties can influence practice (Greco & Eisenberg 1993). It has been suggested that purchasers can play an important role in implementing research findings (Haines & Jones 1994). Indeed, the separation of purchasers and providers has been viewed as an opportunity to use knowledge about effectiveness to improve health services (Dunning et al. 1994). We report a study the aim of which was to explore the impact that a specific brief external intervention might have on a detailed aspect of clinical practice: the use of corticosteroids in preterm labour. The intervention was initiated by public health physicians on behalf of a Health Authority. It formed a part of the Getting Research Into Practice (GRIP) initiative in the old Oxford Health Region, UK.  The administration of corticosteroids to mothers expected to deliver prematurely reduces neonatal mortality and morbidity (Crowley et al. 1990). The first trial which suggested that corticosteroids were effective in this role was published in 1972, and evidence from 12 trials was assembled in a systematic review published in January 1990 (Crowley et al. 1990). Despite the accumulating evidence, in 1991 many women delivering prematurely in the UK and elsewhere were not receiving corticosteroids (Anon 1992;Donaldson 1992). The apparent failure of obstetricians to make full use of this treatment has been cited as an example of the delayed implementation of research findings that can occur in clinical practice (Haines & Jones 1994; Enkin 1996).  相似文献   
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The reproducibility and validity of a self‐administered 142‐item food‐frequency questionnaire (FFQ) was assessed in a population comprising 124 European and 52 Polynesian (17 Maori and 35 Pacific Island) New Zealanders aged 40–65 years. Reproducibility correlation coefficients, determined by administration of the same questionnaire on two occasions 3 years apart, were higher in European than Maori and Pacific Island. participants, ranging from 0.47 to 0.87 in Europeans (median 0.66) and from 0.41 to 0.79 in Maori and Pacific Island people (median 0.44). In general, there were no significant differences in mean nutrient intakes calculated from the two FFQs by Europeans or Maori and Pacific Island participants despite their cultural and language differences. When the FFQ was compared with a 3‐day food diary in a sub sample of 101 Europeans, 15 Maori and 22 Pacific Islanders, the validity was good for most nutrients, with overestimation of a few nutrients in each ethnic group. Correlation coefficients between the 3‐day food diary and FFQ ranged from 0.41 to 0.81 in Europeans (median 0.48) and from 0.36 to 0.56 in Maori and Pacific Island people (median 0.55). Ratios of energy intake to resting metabolic rate suggested that Maori and Pacific Island people were more likely to underestimate their habitual energy intake by the 3‐day diet diary method compared to Europeans, but that Europeans were more likely to underestimate total energy intake by the food frequency method and Pacific Island participants to overestimate it. Obese Europeans and Maori were more likely to under‐report dietary intakes by the 3‐day diary method. We conclude that our FFQ performed better in European than Maori and Pacific Island participants.  相似文献   
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We designed and evaluated a program to teach internal medicine residents behavioral counseling skills for multiple risk factor modification. Integrating physician-patient communication, negotiation skills, and the transtheoretical model of behavior change, we used small group discussion and standardized patients. The 18 participating residents increased their ability to modify patient behavior during videotaped interviews, mean pretest/posttest score: 33.1/40.1 (Student’s pairedt test, p<.0001). Physician self-efficacy in screening for risk factors and effecting behavioral change in patients was increased (p<.0001), as were positive attitudes toward psychosocial factors (p<.003). Our teaching effectively increased the residents’ self-efficacy and performance of behavioral counseling.  相似文献   
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