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21.
Biochemical markers of nutritional status (albumin, transthyretin, insulin-like growth factor-I and zinc) were measured in slowly growing two- to five-year-old, low-income Parisian children whose weight-for-height or height-for-age z scores (WHZ or HAZ) were between — 1 and — 2 SD of the NCHS median. The results were compared to controls who were matched for age, sex, and ethnic origin with WHZ and HAZ between — 1 and + 2 SD. Mean serum levels of transthyretin, albumin and insulin-like growth factor-I and mean plasma zinc concentrations were significantly lower in the growth-impaired children than in the controls ( p = 0.002, p = 0.006, p = 0.015, and p = 0.035, respectively). While the height-retarded children had low mean serum insulin-like growth factor-I values, the weight-retarded subjects had decreased levels of albumin, transthyretin and zinc when compared to controls. Lower mean levels of nutritional markers in healthy, slowly growing children suggest that inadequate dietary intakes of zinc, protein and/or energy may result in marginal delays in weight and height gains.  相似文献   
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Fifteen cases of pure supradiapragmatic lymphoma with initial prominent antero-superior mediastinal involvement displaying a B-cell pattern of reactivity were studied. These cases occurred in six men and nine women with a median age of 33 years at diagnosis (range, 23 to 75 years). Supradiapragmatic peripheral lymphadenopathies were present in three cases, and intrathoracic extension to the lung, pericardium, or pleura was possible. In five cases a thymic origin was obvious. All cases exhibited a B-cell pattern of differentiation, with a great variety of histopathologic aspects associated with a high frequency of fibrosis and/or necrosis. Hodgkin's disease was initially misdiagnosed in four cases. The evolution was purely local, with extrathoracic extension in five cases, at the ultimate phase of the disease. The prognosis appeared to be poor with only five patients still alive at a median survival time of 16 months. A complete chemoresistance and radio-resistance was observed in seven cases; only two complete remissions were achieved with aggressive chemotherapy. Prolonged remission could be achieved after surgical reduction of the mass. Primary B-cell mediastinal lymphoma appears to be a distinct clinical entity with local evolution and resistance to therapy. A new therapeutic regimen, which could include surgery in some cases, should be found for this disease.  相似文献   
24.
To evaluate the potential advantages of the administration of extradural morphine to control postoperative pain and its effects on respiratory function, 39 patients were randomly assigned to one of two groups before aortic surgery. The first group (20 patients) received intravenous analgesia as required (control group). The second group (19 patients) received extradural morphine in a programmed fashion. During the immediate postoperative period the following parameters were measured in both groups: respiratory rate, vital capacity, peak expiratory volume in the first second, PaO2, PaCO2, arterial pH, heart rate, and systolic and diastolic blood pressure. In the group treated with morphine the postoperative increase in heart and respiratory rate was significantly smaller than in the control group (p less than 0.01). Postoperative forced pulmonary volumes were higher in the morphine group (p less than 0.01). However, there were no differences in time of hospitalization between both groups. There were more complications in the control group, but the difference did not reach statistical significance.  相似文献   
25.
An oil implicated in the Spanish "toxic syndrome" was studied for its effect on fat digestibility and adipose-tissue composition in rats. The effects produced by the mixture of oils and those induced by the presence of oleoanilides were assessed separately. For 4 wk, Wistar rats were fed diets containing either a mixture of oils similar to that constituting the toxic oil, the same mixture of oils supplemented with oleoanilides, or the toxic oil (which also contained oleoanilides) and were then compared with a group fed olive oil. Food consumption fluctuated sharply in the group fed the toxic oil, falling significantly in the last week of the study. The digestibility coefficient of the various fats was similar, although the rats fed the toxic oil did absorb less fat because of the lower intake. The nitrogen content of the periovarian adipose tissue was highest in the rats fed the toxic oil, and the adipose-tissue fatty acids most affected by this treatment were linoleic and linolenic acid. The delta-9 desaturase activity, measured in terms of the C16:1/C16:0 and C18:1/C18:0 ratios, was significantly less in the group fed the toxic oil, which suggests functional modifications of the adipocyte related to lipogenesis.  相似文献   
26.
THYMUS SERPYLLOIDES ssp. GADORENSIS is endemic in the Betic region (Spain). Gas chromatography and GC/mass spectrometry studies of its essential oil showed its major components to be carvacrol and its biosynthetic precursors (gamma-terpinene and P-cymene).  相似文献   
27.
We present a study "in vitro" of the effect of bleaching agents on dental surfaces using the "Walking bleaching technique". We found that hydrogen peroxide bleached more quickly than carbamide although, after a period of six weeks, the results were the same as far as whitening was concerned. In the scanning electron microscope we observed significantly different changes in each case. Carbamide caused a regular and uniform opening of the enamel prisms of the surface while hydrogen peroxide produced more severe superficial destruction with the appearance of patterning similar to the acid etching, and the presence of some crystalline areas emerging from the body of the prisms.  相似文献   
28.
The data concerning the effects of age on the brainstem are scarce and few works are devoted to the human vestibular nuclear complex. The study of the effects of aging in the vestibular nuclei could have clinical interest due to the high prevalence of balance control and gait problems in the elderly. We have used in this work eight human brainstems of different ages sectioned and stained by the formaldehyde-thionin technique. The neuron's profiles were drawn with a camera lucida and Abercrombie's method was used to estimate the total number of neurons. The test of Kolmogorov-Smirnov with the correction of Lilliefors was used to evaluate the fit of our data to a normal distribution and a regression analysis was done to determine if the variation of our data with age was statistically significant. Aging does not affect the volume or length of the vestibular nuclear complex. Our results clearly show that neuronal loss occurs with aging in the descending (DVN), medial (MVN), and lateral (LVN) vestibular nuclei, but not in the superior (SVN). There are changes in the proportions of neurons of different sizes but they are not statistically significant. The neuronal loss could be related with the problems that elderly people have to compensate unilateral vestibular lesions and the alterations of the vestibulospinal reflexes. The preservation of SVN neurons can explain why vestibulo-ocular reflexes are compensated after unilateral vestibular injuries.  相似文献   
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Restriction fragment length polymorphisms of total DNA and rDNA were used to study the relationship between 11 isolates of Xanthomonas maltophilia, obtained from seven patients with nosocomial bacteremia in four distinct wards of a single hospital, and the type strain of the species, ATCC 13637. Our results indicated that there were episodes of cross-infection among the patients of two wards, but there were also independent infectious episodes in the two other wards.  相似文献   
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