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21.
R Mokni A Chakar F Bleiberg-Daniel JL Mahu PA Walravens P Chappuis J Navarro D Lemonnier 《Acta paediatrica (Oslo, Norway : 1992)》1993,82(6-7):539-543
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
22.
Pied S; Voegtle D; Marussig M; Renia L; Miltgen F; Mazier D; Cazenave PA 《International immunology》1997,9(1):17-25
TCR V beta usage was examined in C57BL/6 mice infected with Plasmodium
yoelii. In addition to a polyclonal T cell activation, already described, a
superantigenic-like activity was observed during the acute infection. This
superantigenic activity induces a preferential deletion without prior
expansion of CD4+ and CD8+ T cells bearing the TCR V beta 9 segment. The
superantigen could be released by the parasite at different stages of its
development since the deletion of V beta 9+ T cells was observed in blood
and lymph nodes of mice infected either with sporozoites or with
erythrocytic stages. Injection of sporozoite or parasitized erythrocytes to
newborn mice led to a deletion and anergy of peripheral V beta 9+ T cells,
without affecting thymic T cell populations. These observations suggest
that the superantigen is released at very low concentrations during
parasite development. The role of such parasite superantigenic activity in
infectivity can be underlined by the observation that congenic BALB.D2
Mis1a mice lacking V beta 9 T cells are more susceptible to infection by P.
yoelii.
相似文献
23.
The antiviral activity of zinc salts against rhinovirus types 1A and 39 was assayed by yield reduction and inhibition of cytopathic effect in cell culture. The findings indicate that the zinc salts tested have low in vitro therapeutic indices and suggest that the possible beneficial effects of zinc lozenges in reducing cold symptoms may not be related to selective antirhinovirus activity. 相似文献
24.
G. J. Wiener MD T. M. Morgan PhD J. B. Copper PA W.C. Wu MB BS D. O. Castell MD J. W. Sinclair PA Dr. J. E. Richter MD 《Digestive diseases and sciences》1988,33(9):1127-1133
If 24-hour esophageal pH monitoring is to be a useful diagnostic tool, it must reliably discriminate gastroesophageal reflux patients despite daily variations in distal esophageal acid exposure. To address this issue, we studied 53 subjects (14 healthy normals, 14 esophagitis patients, and 25 patients with atypical symptoms) with two ambulatory pH tests performed within 10 days of each other. Intrasubject reproducibility of 12 pH parameters to discriminate the presence of abnormal acid reflux was determined. As a group, the parameters of percent time with pH<4 (total, upright, recumbent) were most reproducible (80%). Therefore, a subject was defined as having gastroesophageal reflux disease if at least one of these three values were abnormal. Intrasubject reproducibility for the diagnosis of reflux disease was 89% for the entire sample. Among subsets, the reproducibility was 93% for the normals and esophagitis patients and 84% for the atypical symptom patients. Total percent time with pH<4 was the single most discriminate pH parameter (85%) and nearly equaled that of the three combined parameters (89%). The intrasubject variability of this parameter was determined by the mean ±2sd of the relative differences between the two test results for all 53 subjects. Total percent time with pH<4 may vary between tests by a factor of 3.2-fold or less (218% higher to 69% lower). We conclude: (1) ambulatory 24-hr esophageal monitoring is a reproducible test for the diagnosis of gastroesophageal reflux disease; and (2) the large intrastudy variability in 24-hr total acid exposure may limit this test's usefulness as a measurement of therapeutic improvement.Supported, in part, by Public Health Services Grant AM 34200-01A1 from NIADDIK. 相似文献
25.
26.
In a prospective, randomized study of insemination with donor semen,
intracervical insemination by straw was compared with insemination using a
cervical cap with an intracervical reservoir. A total of 91 patients
completed 486 treatment cycles. There were no significant differences in
age, parity, indication for insemination by donor, or method of cycle
monitoring between women who became pregnant and those who did not conceive
with either insemination method. In 236 standard intracervical insemination
cycles, 14 patients became pregnant (5.9% per cycle), whereas 38 patients
conceived in 250 cervical cap cycles (15.2% per cycle). Both the crude
pregnancy rates and the cumulative pregnancy rates calculated by the
Kaplan-Meier life-table method were significantly different (chi(2)-test, P
< 0.001, and log-rank test, P < 0.005 respectively). Pregnancy rates
in artificial insemination with cryopreserved donor semen may be improved
by the use of a cervical cap when compared to cervical insemination by
straw. The use of the cervical cap may prolong the exposure of the
spermatozoa to the cervical mucus and prevent the backflow of semen into
the vagina.
相似文献
27.
For many years it has been known that thyrotoxicosis can worsen asthma, increasing both the frequency and severity of asthma attacks and increasing requirements for medication. Clinical recognition of this association may be difficult. Thyrotoxic asthmatics frequently experience side-effects from medications, particularly beta-receptor agonists and theophyllines. Four case reports of asthmatics in whom thyrotoxicosis was diagnosed are presented. All 4 patients improved on returning to euthyroid status. The mechanism responsible for the harmful interaction is not known. 相似文献
28.
Broncho-alveolar lavage--a window to the lung 总被引:1,自引:0,他引:1
29.
30.