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41.
OBJECTIVE: To determine the relationship between serum gamma-glutamyltransferase (GGT) activity and serum IgG concentration in neonatal crias. DESIGN: Prospective observational study. ANIMALS: 21 llama and 4 alpaca crias from 0 to 5 days old. PROCEDURE: Serum GGT activity was measured, using a commercially available kit. Serum IgG concentration was determined by use of radial immunodiffusion. With a serum IgG concentration of 1,000 mg/dl (considered adequate passive transfer), specificity and sensitivity of serum GGT activity in the detection of failure of passive transfer were determined. Regression models were developed to determine the relationship between serum GGT activity and serum IgG concentration. RESULTS: Sensitivity ranged from 0.56 to 0.89, and specificity ranged from 0.88 to 0.31, depending on the value of serum GGT activity chosen as a threshold. Proportion of crias correctly classified ranged from 0.76 to 0.52. Regression models failed to demonstrate a significant relationship between serum GGT activity and serum IgG concentration. CLINICAL IMPLICATIONS: Passive transfer status in crias cannot be accurately predicted on the basis of serum GGT activity.  相似文献   
42.
The specification of vowel formant bandwidths for speech synthesis has been inconsistent in the past, perhaps due to the difficulty of measuring formant bandwidths in natural speech and the possible perceptual insignificance of formant bandwidths on the intelligibility of synthetic speech. Here, regression equations are presented for the estimation of formant bandwidths based on measurements from natural speech which is based only on formant center frequency and independent of other formant values. Current usage, as well as comparison with another well-known estimation algorithm suggests that the new procedure should be quite acceptable for some types of speech synthesis.  相似文献   
43.
Unstable expansion of the CTG repeats in the 3' untranslated region encoding a member of the protein kinase family in the q13.3 band on chromosome 19 is a mutation specific for myotonic dystrophy. To examine the correlation between clinical expression and CTG trinucleotide repeat length, we carried out Southern blot analysis in a family with myotonic dystrophy. In this pedigree, the expanded CTG repeats were transmitted maternally. The mother had three female children. The mother had about 200 CTG repeats, and the number of repeats for each child was about 800, 1500 and 1600 in birth order. The mother and the patient with 800 repeats were unaware of muscle weakness or myotonia. Symptoms were present from age 3 years in the patient with 1500 repeats and from birth in the one with 1600 repeats. Although the mother menstruated regularly, the patients with 800 and 1500 repeats both menstruated irregularly, and the one with 1600 repeats has never menstruated. The age of onset and severity of the disease were correlated with the size of the expanded repeats. Endocrinological studies revealed that the basal levels of the gonadotropins, PRL and E2 were within normal range, and a pituitary response to LHRH was observed. These data suggest that the amenorrhea and menstrual irregularities were caused by a suprahypophyseal dysfunction. When expanded CTG repeats are transmitted maternally, abnormal products resulting from the metabolic disturbance in the affected mother may harm the fetus in utero. A heterozygous fetus, who has more CTG repeats, may be unable to metabolize the pathologic products sufficiently and therefore may become more severely affected. This may explain the exclusive maternal transmission of congenital myotonic dystrophy.  相似文献   
44.
The Cuban recombinant vaccine against the hepatitis B virus was applied to a group of individuals over 65 from a geriatric home in Havana City. Dose of 20 ìg were administered within a scheme from 0.1 to 6 months in order to study its immunogenicity, which was evaluated at 2, 7, and 12 months after the first dose. 47.1% of protective titres and geometrical mean of 6.04 UI/L were obtained after 60 days. 100% of seroconversion (UI/L) and seroprotection (10 UI/L) and geometric mean of 136.93 UI/L were obtained when the immune response was evaluated on the 7th month. Finally, after a year, seroconversion and seroprotection were also of 100%, and the geometric mean was of 204.61 UI/L. It was proved the high immunogenic power of this vaccine, which makes it recommendable to protect this age group from the hepatitis B virus.  相似文献   
45.
Prostate cancer requires the attention of social workers in health care for three reasons: the growing elderly population which will increase the number diagnosed, the recent introduction of new treatments and the lack of social acceptability for this condition. Interventions for prostate cancer are specific to the stage of the disease. These individual, family and group interventions are a model for social work services to elderly men with other forms of cancer. Social workers have opportunity to research quality of life and decision-making issues to enhance medical practise in prostate cancer.  相似文献   
46.
Unequal metabolic responses to trauma by women and men have been suggested, but an explicit investigation demonstrating this conjecture has not been made. The responses of resting energy expenditure (REE) and nitrogen balance for 3 days before and 7 days after skeletal trauma were determined for female and male rats. Food intake and body weight were recorded daily, and 24-h urine samples were collected. Baseline REE and nitrogen balance were obtained for 3 consecutive days before induction of trauma. Then rats were divided into female trauma (n = 8), male trauma (n = 7), female control (n = 8), and male control (n = 7) groups. Trauma was produced by bilateral femoral fracture to anesthetized rats. Control rats were anesthetized without skeletal trauma. Traumatized rats were fed ad libitum for 7 days, and control rats were pair fed with the traumatized rats. The results showed that REE increased and nitrogen balance decreased in traumatized male rats relative to their controls. Traumatized female rats had increased REE and unchanged nitrogen balance compared with their controls. Traumatized female rats had a larger percentage increase in REE on days 5 through 7 than did traumatized male rats. These findings demonstrate a difference between female and male rats in response to trauma. Female rats use more energy and lose less nitrogen after trauma than do male rats. The results suggest that recommendations for increased energy and protein needs after trauma should consider the sex of the subject intended to be fed.  相似文献   
47.
The beta subunit of human chorionic gonadotropin is potentially encoded by six genes, which can be categorized into two types based on a sequence change at codon 117: GCC for the type I and GAC for the type II genes. We previously showed that, whereas type I genes were exclusively expressed in normal breast tissues, expression of type II genes was associated with malignant transformation (Bellet, D., et al. Cancer Res., 57: 516-523, 1997). We designed a simple and robust test (the CG117 assay) that measures the percentage of type II over both types of chorionic gonadotropin beta mRNAs. Normal breast tissues consistently had a negative CG117 index, whereas cancer breast tissues showed indexes ranging from 0 to 100%. The prognostic significance of the CG117 index was investigated in a series of 99 unilateral invasive primary breast cancer patients with known long-term outcome (median follow-up, 9 years). The CG117 index was positive in 48 (48.5%) of the 99 tumor mRNA samples. The index was not significantly associated with standard prognostic parameters, including clinical and macroscopic tumor size, histopathological grade, and lymph node status or steroid receptor status. Patients with a positive CG117 index in primary tumor mRNA had significantly shorter metastasis-free survival (P = 0.014) and overall survival (P = 0.038) after surgery, compared to patients with a negative index. The prognostic significance of the CG117 index persisted in Cox multivariate regression analysis, both for metastasis-free survival (P = 0.008) and overall survival (P = 0.016), together with lymph node status (P = 0.027 and P = 0.009, respectively). These findings indicate that the CG117 index may contribute to the identification of high-risk breast cancer patients.  相似文献   
48.
49.
A single randomized trial evaluated the use of intravenous cyclosporine treatment for severe attacks of ulcerative colitis. The perceived efficacy and safety of this intervention were measured through a survey of the membership of the Canadian Association of Gastroenterology (CAG). METHODS: All CAG members were mailed a survey with questions regarding their familiarity with the data supporting the use of cyclosporine, their perception of the efficacy and toxicity of the drug, and whether patients who fail conventional treatment should receive this therapy. The proportion of respondents who had used cyclosporine to treat severe ulcerative colitis was determined. RESULTS: One hundred and sixty-one responses were received (34% response rate). Sixty-four per cent of respondents were academic faculty members and 82% treated patients with severe colitis. Using multivariate analyses, positive associations were found between the respondents' age (P = 0.004) and subspecialty training in gastroenterology (P = 0.001), and whether respondents treat patients with severe ulcerative colitis. Twenty-six per cent of individuals had prescribed cyclosporine for this indication, of whom 88% were in academic practice (P = 0.007). Over 90% of respondents believe that further clinical trials are needed before cyclosporine becomes accepted as standard therapy. CONCLUSIONS: Although the use of cyclosporine is measurable among Canadian gastroenterologists, the majority believe that further clinical trials are necessary before the drug is accepted as a standard therapy.  相似文献   
50.
A parameter-free geometric model for nuclear absorption is derived from microscopic theory. The expression for the absorption cross section in the eikonal approximation taken in integral form is separated into a geometric contribution, described by an energy-dependent effective radius, and two surface terms which are shown to cancel in an asymptotic series expansion. For collisions of light nuclei, an expression for the effective radius is derived using harmonic-oscillator nuclear density functions. A direct extension to heavy nuclei with Woods-Saxon densities is made by identifying the equivalent half density radius for the harmonic-oscillator functions. Coulomb corrections are incorporated and a simplified geometric form of the Bradt-Peters type obtained. Results spanning the energy range of 1 MeV/nucleon to 1 GeV/nucleon are presented. Good agreement with experimental results are obtained.  相似文献   
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