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41.
Cytomegalovirus (CMV) is probably the most common agent of prenatal infection of the newborn, and one of 20 congenitally infected newborns shows serious symptoms. It was therefore considered important to be able to differentiate primary CMV from reactivation in pregnant females. A urea denaturation test was used to distinguish primary from secondary rubella infection in which the urea is included in the wash step of the standard IgG ELISA. This resulted in the removal of low-avidity antibodies, which are the antibodies produced early in infection. A group of CMV IgM-negative and -positive sera were tested, and all but one showed moderate to high avidity, with an avidity index reading of more than 30%. Among a group of babies 3-12 months of age, who were CMV IgM positive, 55% (16 of 29) showed low-avidity CMV antibodies. A small group of renal transplant patients and patients with clinically and laboratory-confirmed CMV gave more or less predicted avidity index results. It appears that, with the method used at this laboratory, the urea denaturation test can be applied to CMV to determine primary infection or reactivation in the majority of cases.  相似文献   
42.
Background: Zinc is an essential trace element for the normal growth and development of human beings. The main objective was to evaluate the nutritional status of zinc and its association with nutritional indicators in a series of children with chronic diseases. Methods: The prevalence of patients with dietary zinc deficiency or deficit zinc intake (<80% DRI: dietary reference intake) was analyzed through prospective 72 h dietary surveys, and serum zinc deficiency or hypozincemia (≤70 µg/dL in children under 10 years of age in both sexes and in females older than 10 years and <74 μg/dL in males older than 10 years) was measured through atomic absorption spectrophotometry. The participants were classified according to their nutritional status by body mass index (BMI). Results: Mean serum zinc level in obese (87 µg/dL), undernourished (85 µg/dL), and eutrophic children (88 µg/dL) were normal, but in the undernutrition (60% DRI) and eutrophic (67% DRI) groups the mean dietary zinc intake was low compared to that in the obesity group (81% DRI). There were different associations between nutritional parameters, dietary zinc intake, and serum zinc. All patients with hypozincemia had dietary zinc deficiency. Conclusions: In the whole series, 69% of participants showed a zinc intake lower than recommended and might be at high risk of zinc deficiency.  相似文献   
43.
单纯性肥胖症瘦素水平的临床意义   总被引:2,自引:0,他引:2  
目的 :探讨单纯性肥胖症血清瘦素 (Leptin)及其临床意义。方法 :用ELISA法检测 48例单纯性肥胖症 (体重指数≥ 2 5 )和 40例健康对照者的血清Leptin水平。结果 :肥胖症组血清瘦素水平明显高于健康对照组 (P <0 .0 0 1) ,女性几乎较男性高 2倍以上。瘦素与BMI及脂肪含量呈正相关 (相关系数r分别为男性r =0 .36 ,0 .33 ,P <0 .0 5 ;女性r =0 .90 ,0 .87,P <0 .0 5 )。结论 :单纯性肥胖症血清瘦素水平升高 ,提示瘦素抵抗存在 ,可能在肥胖的发生发展中起重要作用  相似文献   
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A Monte Carlo simulation has been developed to predict the quality of time-resolved images of the breast by transillumination. The smallest diameter of a detectable carcinoma located in the breast has been computed. The simulation suggests that time-resolved imaging of the breast is possible and invaluable in the near infra-red (NIR) by transillumination. The enhancement of the transfer function by the introduction of time-resolved detection is limited by the contribution of noise at short integration times. The estimated diameter of the smallest detectable sphere is derived from the image quality index (IQI) theory and its value is around 4 mm. The simulated images of an absorbing sphere (approximating the carcinoma) within a homogeneous medium (approximating the surrounding tissue) show a significant improvement of the image with short integration time.  相似文献   
48.
Genetic studies have shown that both childhood and adult body mass index are substantially heritable. The evidence for shared family environmental influences is largely absent, even though there are clear indications that secular changes in energy expenditure have brought about a significant increase in the prevalence of obesity. This apparent inconsistency may be explained by the dual phenomena of the near-universality of access to environments that facilitate reductions in energy expenditure (e.g., TV as a recreational pastime), together with heritable individual differences in the response to or utilization of these environments. The impact of changes in nonshared environments on body weight can be estimated from biometrical genetical studies and is found to be both small and relatively short-lived. Genetic and environmental results from longitudinal studies are consistent with what is known about the changing distribution of adiposity during adulthood and clinical experience of the difficulty of maintaining behavioral-induced weight loss.  相似文献   
49.
Aims: a) To identify which pretreatment clinical or blood parameters werepredictive of patient survival in small-cell lung cancer (SCLC) in aretrospective analysis. b) To validate three known prognostic indices: RoyalMarsden Model (index 1), London Group (index 2) and Manchester Score (index3).Patients and methods: From 1981 to 1993, 341 SCLC patients were treatedwith chemotherapy with or without surgery or radiotherapy. Univariate andmultiple regression analyses of survival were performed and the feasibilityof these models was explored, index 1: Karnofsky index, albumin, sodium andalkaline phosphatase; index 2: ECOG performance status (PS), albumin andalanine transaminase; and index 3: lactate dehydrogenase (LDH), diseaseextent, sodium, Karnofsky index, alkaline phosphatase and bicarbonate.Results: Significant prognostic factors for survival after univariate andmultiple regression analysis were: disease extent, PS, creatine kinase,neutrophilia, LDH, hypoalbuminemia, hyperglycemia and bicarbonate. A newprognostic index was performed that included LDH, hypoalbuminemia,neutrophilia, disease extent and PS. It defined three prognostic groups (PG).Median survival and two-year survival for these PG were 12.3, 8 and 3.4 monthsand 16.5%, 2.3% and 0%, respectively. The following PGwere identified after application of the three models proposed: Index 1identified two PG with 0% and 16.6% two-year survival (P <0.001); index 2 detected three PG with 0%, 5% and 15.7%two-year survival (P < 0.001) and index 3 detected three PG with 0%,2.5% and 16.2% two-year survivals, respectively (P < 0.001).Conclusion: A new prognostic index is proposed allowing identification ofthree different PG. The feasibility of three known prognostic models wasvalidated and demonstrated. Variables other than disease extent or PS (albuminor LDH) should be taken into account in designing future clinical trials.  相似文献   
50.
The cerebrospinal fluid (CSF) of 37 patients with early Lyme neuroborreliosis (ELN) and of 10 patients with late Lyme neuroborreliosis (LLN, duration of symptoms 7 months) was investigated for typical features differentiating between acute and chronic courses of disease. Individual patients were studied after 2 and 4 weeks, and 3, 6, and 12 months. Patients with ELN presented predominantly with symptoms of the peripheral nervous system, while patients with LLN generally suffered from symtoms of the central nervous system. At the first lumbar puncture, patients with ELN revealed a more intense pleocytosis in the CSF (P < 0.02) and a higher intrathecal synthesis of total IgM (P < 0.0003) and ofBorrelia burgdorferi-specific IgM antibodies (P < 0.01). At the same time, in patients with LLN, the blood-CSF barrier was more severely impaired (P = 0.03), and local production of total IgG (P = 0.0001), ofB. burgdorferi-specific IgG antibodies (P = 0.03) and of total IgA (P = 0.001) was more markedly increased. The quantity of intrathecally producedB. burgdorferi-specific IgA antibodies did not differ between the two study groups. Clinical recovery was usually accompanied by a considerable improvement of the blood-CSF barrier function and pleocytosis. After 6 months, the intrathecal synthesis of total IgG had significantly decreased in patients with ELN but not in those with LLN. At the same time, the CSF of most patients in both study groups still contained intrathecally producedB. burgdorferi-specific IgG antibodies. In the absence of clinical illness or symptoms of inflammation 6 and 12 months after treatment,B. burgdorferi-specific IgG antibodies in the CSF might simply indicate an anamnestic reaction to a previous infection of the central nervous system. Six months after antibiotic treatment, patients with ELN still revealed evidence of intrathecal synthesis of total IgM, whereas those with LLN did not. These antibodies, however, were not related toB. burgdorferi.  相似文献   
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