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1.
Nutritional dwarfing refers to a condition in which maladaptive eating patterns play a primary role in poor linear growth and delayed pubertal development. The present controlled study assesses whether nutritionally dwarfed children and adolescents differ in their psychosocial adjustment from healthy children and adolescents of comparable height in ways that might account for their undernutrition. Children with nutritional dwarfing (n = 16) were compared by standardized questionnaires with a short-stature (ie, heights below the fifth percentile) control group composed of children and adolescents with constitutional growth delay and/or familial short stature (n = 31). Scores on a self-report screening questionnaire for eating disorders did not differentiate the groups. Moreover, the vast majority of nutritionally dwarfed patients expressed a desire to have a heavier physical appearance. Whereas the groups were generally similar in self-perceptions of domain-specific competencies and positive psychosocial adjustment, the parents of nutritionally dwarfed children reported that their children showed significantly fewer externalized behavior problems. These findings suggest the existence of an eating disturbance that compromises growth in childhood and/or adolescence which, unlike anorexia nervosa, is not associated with evidence of psychopathology. 相似文献
2.
Charles R. Kiefer James B. McKenney Jane F. Trainor Richard W. Lambrecht Herbert L. Bonkovsky Lawrence M. Lifshitz C. Robert Valeri L. Michael Snyder 《The American journal of pathology》1998,153(3):703-708
To further the understanding of oxidative effects on inflammation injury to muscle fiber structure, fluorescent imaging analysis of human striated muscle tissues from a variety of inflammatory or postinflammatory etiologies was undertaken in a search for accumulated coproporphyrin, a red autofluorescent byproduct of heme biosynthesis that would theoretically be formed under oxidative insult. Using a differential excitation method of in situ analysis, porphyrin autofluorescence was detected in intact fibers within the context of the yellow autofluorescent subsarcolemmal lipofuscin granules. Relative measurements of porphyrin concentration in the granules from different patients indicated that the acute/subacute inflammatory specimens grouped significantly higher than the more chronic inflammatory and nonpathological specimens. Myoglobin was also found to be associated with the granules. Myoglobin heme iron could potentially serve as a Fenton reagent for the intracellular generation of hydroxyl radicals, which are responsible for the oxidation of the porphyrinogens. High-performance liquid chromatography analysis of extracted dense particles revealed coproporphyrin as the sole porphyrin present. The observation of coproporphyrin within lipofuscin granules, previously unreported, suggests that lipofuscin accumulation in striated muscle may begin under conditions of acute oxidative stress, as marked by the oxidation of extramitochondrial porphyrinogens that are immediately incorporated into the granules. 相似文献
3.
The antibody response to the synthetic polypeptide, poly(LTyr, LGlu)-poly(DLAla)–poly(LLys), [(T, G)-A–L], injected entrapped in liposomes which served as adjuvant, has been analyzed. The liposomes used were composed of phosphatidylcholine, cholesterol, dicetylphosphate and DL α-tocopherol (molar ratios as 4:3:0.1:0.5) and therefore, were negatively charged. Since the (T, G)-A–L is also negatively charged, no free complexes were formed. The (T, G)-A–L was found to be entrapped inside the enclosed volume of the liposomes, and no (T, G)-A–L antigenic determinants could be detected on the liposomal membranes. Injection of high-responder C3H.SW (H-2b) mice with (T, G)-A–L-bearing liposomes demonstrated that the i.p. and the i.v. routes of immunization were efficient in eliciting (T, G)-A–L-specific antibodies, whereas the i.d. injection led to poor antibody responses. The latter route of immunization is the most effective when (T, G)-A–L is injected in complete Freund's adjuvant (CFA). When low doses (0.1 and 1 μg) of (T, G)-A–L were used for immunization, the liposomes were better adjuvants than CFA. The effectiveness of the liposomes as immunological adjuvants was also shown in their ability to induce high-potential, primed memory cells. The pattern of low (H-2k, a) and high (H-2b) responsiveness to (T, G)-A–L was retained following immunization with (T, G)-A–L entrapped in liposomes, as tested in two pairs of congenic strains. (T, G)-A–L-specific antibodies induced by injection with 1μ antigen entrapped in liposomes bear the (T, G)-A–L site-related idiotypic markers of C3H.SW (Igh-1a) mice in a significantly higher frequency than the homologous idiotypes, namely the antibodies elicited in this strain against (T, G)-A–L in CFA. Thus, liposomes may serve as adjuvants for the production of relatively restricted (T, G)-A–L-specific antibodies of high qualitiy. 相似文献
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Molecular testing is no longer exotic, distant, or complex. It's moving into your lab and revolutionizing the rapid diagnosis of pathogenic organisms as well as your role as a laboratorian. 相似文献
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7.
M Lifshitz O Weinstein V Gavrilov G Rosenthal T Lifshitz 《Therapeutic drug monitoring》1999,21(5):544-546
This study was designed to measure acetaminophen (paracetamol) levels in tears, and to compare it to serum levels. Paracetamol levels were measured in 20 paired tears and serum samples from 10 healthy volunteers, 1 and 2 hours after ingesting 1.5 g paracetamol. Tears were collected using glass microcapillary tubes while stimulating the conjunctiva with a small sponge placed in the lower fornix. Blood samples were taken simultaneously. The samples were analyzed for paracetamol levels using homogeneous enzyme immunoassay. Tears and serum paracetamol levels 1 hour after ingestion were 16.3 microg/mL +/- 7.2 (mean +/- SD), and 21.4 microg/mL +/- 7.7 (mean +/- SD) respectively. Tears and serum levels 2 hours after ingestion were 14.4 microg/mL +/- 7.8 (mean +/- SD), and 17 microg/mL +/- 7.6 (mean +/- SD) respectively. Tears and serum paracetamol levels of all the 20 paired samples (1 h and 2 h after ingestion) were 15.35 microg/mL +/- 7.4, and 19.25 microg/mL +/- 7.8, respectively (mean +/- SD). There was a strong and highly significant correlation between paracetamol levels in serum and in tears 1 and 2 hours after ingestion (r = 0.8, p = 0.005, r = 0.85, p = 0.002 respectively). Mean +/- SD ratio of tears/serum paracetamol levels 1 hour and 2 hours after ingestion were 0.77 +/- 0.21 and 0.81 +/- 0.25 respectively. Delta tears (difference in mean levels at 1 and 2 hours) paracetamol levels is significantly correlated with delta serum levels (r = 0.7, p = 0.025). A reliable, convenient, and feasible noninvasive method is described for measuring paracetamol in tears. There is no information in the literature about tears paracetamol secretion, and little information of tears drugs concentration. 相似文献
8.
Talavera JO Wacher NH Laredo F López A Martínez V González J Lifshitz A Feinstein AR 《Archives of medical research》2000,31(6):576-584
BACKGROUND: When a CT scan is not available, an early accurate clinical diagnosis of ischemic stroke is essential to initiate prompt therapy. Our objective was to construct a clinical index that is easy to use when stroke patients are first evaluated at the hospital, to identify those who probably are experiencing an acute ischemic episode. The study was conducted at a university-affiliated medical referral center and two community general hospitals in Mexico. METHODS: Clinical records were reviewed for 801 patients with sudden onset of a focal or global neurologic dysfunction, presumably of vascular origin lasting more than 24 h. Eligibility criteria for this study were admission to the hospital within the first 24 h after symptomatic onset, CT scan diagnosis between 24 and 72 h, and age >45 years. Ischemic stroke included cases of arterial brain infarction, while nonischemic stroke included subarachnoid or intraparenchymatous hemorrhage, mass lesion, venous infarction, and in cases without a CT scan evidence that could explain the clinical manifestations. Data excerpted for analysis were age, sex, history of diabetes mellitus or previous stroke/transient ischemic attack (TIA), time of onset of symptoms, presence of headache, vomiting, neck stiffness, hemiplegia, leukocytosis or atrial fibrillation, diastolic blood pressure, and Glasgow coma scale (GCS) rating. Two multivariable analyses were used: 1) step-wise multiple logistic regression (SMLR), and 2) conjunctive consolidation (CC). RESULTS: After appropriate exclusions, the study proceeded with 83 ischemic and 42 nonischemic stroke patients. With SMLR, six variables were selected as predictive for ischemic stroke, including neck stiffness, diastolic blood pressure, previous history of stroke/TIA, hemiplegia, GCS, and atrial fibrillation. An appropriate sum of weighted ratings had a positive predictive value (PPV) of 100% for ischemic stroke. With consolidated categories, the PPV was 97% when patients had the following: no neck stiffness; no atrial fibrillation but history of stroke/TIA and GCS > or =12, or no neck stiffness but atrial fibrillation. CONCLUSIONS: Among patients with acute stroke, clinical data can be used to identify a group with a high probability of ischemic stroke. There are slightly different results between both methods; while SMLR includes the four variables selected by CC, the latter included neither diastolic blood pressure nor hemiplegia/hemiparesia. However, CC results seem easier to understand and interpret than with SMLR. 相似文献
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Yonatan Perez Libe Gradstein Hagit Flusser Barak Markus Idan Cohen Yshaia Langer Mira Marcus Tova Lifshitz Rotem Kadir Ohad S Birk 《European journal of human genetics : EJHG》2014,22(5):703-706
Foveal hypoplasia, always accompanied by nystagmus, is found as part of the clinical spectrum of various eye disorders such as aniridia, albinism and achromatopsia. However, the molecular basis of isolated autosomal recessive foveal hypoplasia is yet unknown. Individuals of apparently unrelated non consanguineous Israeli families of Jewish Indian (Mumbai) ancestry presented with isolated foveal hypoplasia associated with congenital nystagmus and reduced visual acuity. Genome-wide homozygosity mapping followed by fine mapping defined a 830 Kb disease-associated locus (LOD score 3.5). Whole-exome sequencing identified a single missense mutation in the homozygosity region: c.95T>G, p.(Ile32Ser), in a conserved amino acid within the first predicted transmembrane domain of SLC38A8. The mutation fully segregated with the disease-associated phenotype, demonstrating an ∼10% carrier rate in Mumbai Jews. SLC38A8 encodes a putative sodium-dependent amino-acid/proton antiporter, which we showed to be expressed solely in the eye. Thus, a homozygous SLC38A8 mutation likely underlies isolated foveal hypoplasia. 相似文献