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Quality control in cervical cytology   总被引:2,自引:1,他引:2       下载免费PDF全文
From surveys conducted by the authors it is concluded that the best and most acceptable quality control methods in cytology are those from within the laboratory. Most of these have results which can be reported centrally. Where the overall control and codes of practice are high, there the results are the most reliable, as sources of error from whatever cause are quickly brought to light. These conclusions are illustrated by data from the five centres and correlated in the tables.  相似文献   
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The Coping Inventory for Stressful Situations (CISS; Endler & Parker, 1990) is a self-report measure of Emotion-, Task-, and Avoidance-oriented coping. The psychometric properties of the CISS were evaluated in a large sample of outpatients with major depressive disorder (N = 298). The CISS scales demonstrated good reliability and support for their factorial validity was obtained. Relationships between the CISS scales and the broad personality domains from the five-factor model of personality, as well as two measures of emotional distress, were examined. Less-adaptive coping strategies (i.e., Emotion-oriented coping) were associated with less-adaptive personality traits (i.e., Neuroticism) and with psychological distress (i.e., Depression), whereas the reverse was found regarding adaptive coping strategies (i.e., Task-orientated coping). The incremental validity of the CISS was demonstrated by multiple-regression analyses that found two CISS scales accounted for significant variance in psychological distress beyond that contributed by the demographic and personality variables.  相似文献   
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Two clones, pCZTH5-8 and pCZTH12-8, were isolated from a female chicken genomic library by screening with sequences obtained from genomic libraries which had been constructed from a terminal region of a single Z chromosome of chicken utilizing laser microbeam irradiation and PCR amplification. Fluorescencein situ hybridization to the mitotic Z chromosome and the lampbrush ZW bivalent of chicken demonstrated that both the cloned sequences are located in the heterochromatic region of the Z chromosome at the end opposite to the pairing region with the W chromosome. The sequences pCZTH5-8 and pCZTH12-8 are distributed widely on both the telomeric bow-like loops (TBL) and the region I (short loops region) of the Z lampbrush chromosome. These clones, pCZTH12-8 particularly notably, hybridized also to the TBLs of lampbrush bivalents 1–4 of chicken. Both sequence are transcribed in the lampbrush stage oocytes on the Z chromosome and on other macrobivalents. The subfragment of pCZTH5-8 which hybridizes to the TBLs and the insert of pCZTH12-8 contain regions that are closely similar in sequence. The pCZTH5-8 sequence has no internal repeats and may be part of the 24-kb macrosatellite repeating unit that is evident afterNhel digestion of the genomic DNA. A cloned 24-kb unit, pFN-1, does not show significant DNA curvature, but cytosines of its CpG dinucleotides may be highly methylatedin vivo. This contrasts with the repeat sequences of the W heterochromatin which not only have highly methylated CpG but are also strongly curved. The 24-kb unit is repeated about 830 times in the diploid genome of a female chicken, suggesting that nearly the entire terminal heterochromatin on the Z chromosome consists of this macrosatellite family. Sequences of the greater part of the pCZTH5-8 are restricted to the genusGallus but the sequence of one subregion which hybridizes to TBLs is present in the genomes of the order Galliformes.accepted for publication by M. Schmid  相似文献   
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This review examines the energetics and metabolic parameters which influence the effectiveness of gastric restrictive surgery in achieving weight loss in the clinically severely obese patient. Among the subjects discussed are the metabolic determinents and consequences of obesity, energy expenditure and its components, factors other than dietary restriction and weight loss which affect energy expenditure, and the metabolic risk factors for weight gain. The role of exercise is reviewed, including the effects of exercise on energy balance and the thermic effect of food. The value of combining exercise with diet restriction, the effect of caloric restriction on the capacity to exercise and the place of exercise in the obese diabetic are examined. Finally, the metabolic consequences of gastric restrictive surgery, the adaptive response to surgically induced weight loss and nutritional recommendations following gastric restrictive surgery are reviewed.  相似文献   
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Background: The pharmacokinetic variables of drug clearance and volume of distribution are usually corrected for body weight or surface area. Only recently have the relationships which exist between body size, physiologic function and pharmacokinetic variables been evaluated in the obese population. These effects are not widely known, and data on this and the effects of bariatric surgical procedures are scantily documented in the surgical literature. Methods: Literature review. Results: Drugs with a low or moderate affinity for adipose tissue have a moderate increase in the volume of distribution (Vd), and this correlates with the increase in lean body mass (LBM). Highly lipophilic drugs, with some exceptions, show the expected increase in Vd and prolongation of elimination half-life, indicating a marked distribution into adipose tissue. Drug absorption, in general, is slowed by delayed gastric emptying and is normal when gastric emptying is normal or increased. Most drug absorption occurs in the small intestine where duration of drug/mucosal contact is the most important factor. Conclusions: Drugs whose distribution is restricted to LBM should utilize a loading dose based on ideal body weight (IBW). For those drugs which distribute freely into adipose tissue, the loading dose should be based on total body weight (TBW). Adjustment of the maintenance dose depends on clearance rates. In a few cases dosage adjustment depends on pharmacodynamic data, since drug clearance does not conform to these recommendations, for reasons which remain to be defined. Following bariatric surgery, in the absence of delayed gastric emptying or uncontrolled diarrhea, drug absorption rates are usually comparable to the non-operated patient.  相似文献   
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