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41.
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   
42.
A tRNA operon (trnA) from Lactococcus lactis consisting of seven tRNA genes and a 5S rRNA gene was cloned and sequenced. Promoter-fusion of the trnA promoter to a promoter-less beta-galactosidase gene of Leuconostoc mesenteroides resulted in high levels of beta-galactosidase activity in L. lactis. Searching for sequences with similarity to the sequence of the promoter region revealed a consensus sequence of promoters preceeding rRNA operons and tRNA operons from Lactococcus species including a not previously described conserved sequence (AGTT).  相似文献   
43.
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   
44.
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   
45.
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   
46.
47.
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   
48.
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   
49.
Translation initiation factor eIF-4B promotes the binding of mRNA to 40 S preinitiation complexes and together with eIF-4A possesses RNA helicase activity. To elucidate structural features involved in its function, a series of internal and C-terminal deletions, as well as point mutations, were constructed in the eIF-4B cDNA. The mutated cDNAs were expressed in transiently transfected COS-1 cells, and mutant forms of the factor were overproduced up to about 25-fold over endogenous eIF-4B levels. Inhibition of dihydrofolate reductase (DHFR) synthesis by high levels of eIF-4B variants was determined in vivo, and the binding of the eIF-4B forms to biotinylated RNA was measured in vitro. The results indicate that the N-terminal region containing the RNA binding motif with its RNP1 and RNP2 consensus elements is sufficient for inhibition of DHFR synthesis. Deletion of the RNP1 sequence abrogates RNA binding, but amino acid substitutions at conserved residues do not always inhibit RNA binding. Deletion of the DRYG domain near the middle of eIF-4B results in inhibition of RNA binding, but not of DHFR synthesis. Up to 164 residues of the C terminus are not required for RNA binding, but removal of 226 or more residues completely inhibits RNA binding, perhaps by the loss of two arginine-rich regions. The results suggest that both the RNA recognition motif and the arginine-rich region are required for stable RNA binding but that both are not necessary for in vivo inhibition of protein synthesis.  相似文献   
50.
The present study was undertaken to evaluate the postoperative relapse from the period of unwiring to 1 year postoperatively and its correlation to the amount of mandibular setback and change in vertical dimension after mandibular bilateral sagittal split osteotomy. Twenty-seven patients were evaluated cephalometrically by the time preoperatively, 6 weeks, 6 months and 1 year postoperatively. It was found that 1) the average amount of mandibular setback at pogonion point, 6 weeks postoperatively, is 7.6mm backward and 1.9mm downward, 2) the average amount of horizontal relapse at pogonion point, 6 months and 1 year postoperatively, are 1.9mm and 2.3mm respectively. 86% of the horizontal relapse, 1 year postoperatively, occurs in the first 6 months after removal of intermaxillary fixation, 3) the average amount of vertical relapse at pogonion point, 6 months and 1 year postoperatively, are 0.9mm and 1.1mm upward. 82% of the vertical relapse, 1 year postoperatively, occurs in the first 6 months after removal of intermaxillary fixation, 4) the amount of 1 year postoperatively horizontal relapse is significantly correlated both with the amount of horizontal mandibular set back and vertical downward change (r = 0.58, 0.67, p < 0.001), whereas the amount of vertical relapse is with the vertical downward change only, but horizontal setback isn't.  相似文献   
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