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171.
A part of a larger study of the health behaviors of adolescent women, this investigation examined health-promoting behaviors and the influence of cognitive, social, and environmental factors on these health-promoting behaviors of rural adolescent women. The sample consisted of 128 rural African-American and white adolescent women. Forty-four percent of the variance in health-promoting behavior of this sample was explained by five variables: self-image, problem solving, mother's education, employment status, and family structure. Self-image was the most salient predictor of health-promoting behavior, explaining 33% of the variance.  相似文献   
172.
The commercial broiler industry is a modern day agricultural success due to popular consumer demand, healthy flocks, and least cost production. Preventive medicine is the key for economical control of disease in integrated broiler companies, and includes quarantine-eradication, controlled-exposure, and preventive feed medication. Respiratory and enteric diseases present a continuing, potential threat for economic loss. Most exotic and egg-transmitted poultry diseases have been controlled by reduction or eradication policies. Endemic diseases are controlled by mass vaccination and preventive feed medication. Improvements in genetics, housing, equipment, and disease surveillance has allowed continued improvements in disease prevention. Attention to detail and management of risk is crucial to industry success. With fast industry growth and market maturity of the broiler industry, new challenges have risen. These challenges include increased poultry house density, increasing economic pressures, changing industry attitudes, and increased governmental regulations that will strain the continued success of today's control strategies.  相似文献   
173.
Mesenteric venous thrombosis (MVT) after appendicectomy has not been reported in the pediatric literature. This complication is associated with significant morbidity and mortality rates in adults. The report of this case attempts to analyze the features found in an appendicectomized child documented by radiological examination and surgery before and after starting heparin therapy. Anticoagulation treatment should be started as soon as possible and continued for a long time to decrease the risk of relapse.  相似文献   
174.
The purpose of this investigation was to compare the levels of serum IgG2, the frequency of detection of Gm(23)-negative allotype and frequency of detection of FcgammaRIIa and FcgammaRIIIb receptor haplotypes in 32 refractory, 54 successfully treated and 27 periodontally healthy individuals. Refractory subjects showed mean full mouth attachment loss and/or >3 sites with attachment loss >2.5 mm within 1 year after both scaling and root planing, and surgery plus systemically administered tetracycline. Successfully treated subjects showed mean attachment level gain and no sites with attachment loss >2.5 mm 1 year post-therapy. Periodontally healthy subjects exhibited no pocket depth or attachment level >3 mm, and no evidence of progressing disease during 1 year of monitoring. Blood was obtained from each subject at baseline. Serum IgG2 and Gm(23) allotype were determined using radial immunodiffusion. DNA was extracted from whole blood and the FcgammaR genotypes determined using PCR and allele specific oligonucleotide probes. Significance of differences among clinical groups were sought using the Kruskal-Wallis or chi-square tests. Associations between 2 or more variables were tested using regression analysis. Refractory subjects exhibited higher mean attachment loss and pocket depth than successfully treated or periodontally healthy subjects. Smoking status did not differ significantly among groups. No significant differences in serum IgG2 levels and frequency of detection of Gm(23)-negative allotype were observed among the clinical groups. Serum IgG2 level was positively associated with the number of serum antibody responses to subgingival species (r=0.51, p<0.001). Subjects with the Gm(23)-negative allotype exhibited lower mean levels of serum IgG2 (3.06+/-0.3 versus 3.9+/-0.2, p<0.01) and mean number of serum antibodies to subgingival species (17.7+/-1.7 versus 23.3+/-1.4, p<0.05) than allotype positive individuals. No significant differences in FcgammaR haplotype distribution were observed among the 3 clinical groups. Associations of serum IgG2 level, Gm(23) allotype, FcgammaRIIa and FcgammaRIIIb receptor haplotypes and smoking status were weakly related or not related to clinical status. This lack of relationship may have been due to a reality of no relationship, or the inadvertent pooling of subjects where these factors were of primary importance with subjects in whom these factors played a less important role.  相似文献   
175.
In the treatment of neural crest tumors, such as pheochromocytoma, with[131I]MIBG, bone marrow toxicity limits the amount of administered activity and, thus, a therapeutically useful tumor dose. METHODS: We calculated tumor doses in a series of diagnostic studies with [123I]MIBG using accurate quantification of SPECT and planar scintigraphy. By extrapolating diagnostic results to therapeutic activities of [131I]MIBG, we could compare the results with whole-body doses from a series of therapies. RESULTS: The tumor dose was DT = 2.2 mGy MBq(-1) (median value of 27 measurements, range 0.04 < or = DT < or = 20 mGy MBq(-1) and the whole-body dose in a series of 16 patients undergoing 50 therapies was DWB = 0.12 +/- 0.04 mGy MBq(-1) (mean +/- s.d.). The therapeutic ratio varied between 130 to below 10 in some patients. CONCLUSION: The results were compared with published data. We found clearly skewed distribution of tumor doses, with a majority of tumors receiving only a few mGy per MBq administered activity. In some patients, however, doses did reach 20 mGy MBq(-1).  相似文献   
176.
Villin 14T, a representative domain from the actin severing and bundling protein villin, binds calcium ions and actin monomers. To begin to understand the contributions of mobility to the villin-calcium and villin-actin interactions, relaxation rates for magnetization involving the amide nitrogens and protons have been measured for 15N-labeled villin 14T in solution. Although we have measured the complete set of rates required for a full spectral density map, difficulties in the accurate measurement of relaxation rates for antiphase coherence and two-spin order led us to consider a reduced mapping formalism. From the reduced spectral density map, a model-free analysis, or directly from the measured Nx,y relaxation rates, local variations in mobility along the backbone of villin 14T have been revealed. Fast motions are evident not only at the amino and carboxyl termini but also in the turn between strands beta 4 and beta 5 of the central beta-sheet and in the turn between helix alpha 3 and strand beta 7. Slower motions are suggested for the turn between strands beta 2 and beta 3. Motions on the microsecond to millisecond time scale have been probed directly by examining the dependence of the proton transverse relaxation rate on the spin-locking field strength. Leu11 shows a strong dependence on field strength, implying conformational exchange with a time constant of 125 +/- 69 microseconds. The backbone at the actin-binding interface appears to be rather rigid.  相似文献   
177.
We evaluated 48 archival cases of acute erythroleukemia and divided them into 3 groups: M6a, corresponding to the traditional French-American-British M6 category; M6b, which is pure erythroleukemia; and M6c, in which myeloblasts and pronormoblasts each account for more than 30% of cells by the French-American-British exclusion criteria. No significant differences were noted among the subtypes for ratio of males to females; age; or exposure to toxins, alcohol, or both. However, compared with the patients in the M6a group, patients in the M6b and M6c groups demonstrated a statistically significant increase in cytogenetic aberrations, proliferation markers (proliferating cell nuclear antigen and Ki67), and ringed (type III) sideroblasts. Marked survival differences were noted between the M6a (30.1 +/- 29.5 months) and M6b (3.15 +/- 4.2 months) groups, with patients in the M6c group demonstrating an intermediate prognosis (10.5 +/- 12.7 months). Chemotherapeutic regimens induced remission in all treated patients in the M6a and M6c groups but did not appear to affect the M6b group. However, the patients in the M6c group remained in remission for a significantly shorter period of time than did patients in the M6a group. Overall, survival appeared to depend on the ratio of pronormoblasts to myeloblasts at diagnosis and demonstrated a rapid decline with increasing pronormoblast and decreasing myeloblast counts. We must, therefore, devise chemotherapeutic regimens that target both blastic components of this disease.  相似文献   
178.
STUDY OBJECTIVES: Asymptomatic HIV-infected individuals are increasingly recruited for studies involving invasive procedures such as bronchoscopy. We sought to determine the response to and outcome of a request for a research bronchoscopy in HIV-positive individuals with no respiratory disease, and whether this would adversely affect future decisions to have a medically indicated bronchoscopy. DESIGN AND SETTING: Prospective, semistructured, questionnaire-based study in a London teaching hospital HIV outpatient clinic. PARTICIPANTS: One hundred and seven consecutive HIV-infected eligible individuals. Thirty-one healthy volunteers served as a control group for the subjective response to bronchoscopy. MAIN OUTCOME MEASURES: Subjects' attitudes and responses to requests for bronchoscopy and subsequent behavior when they required medically indicated bronchoscopy. RESULTS: Seventy-five patients (70%) agreed to the procedure in principle, predominantly for altruistic reasons. Thirty-nine subjects underwent bronchoscopy. Five percent found it worse than expected; and 79% agreed to another research bronchoscopy (performed in 11 subjects approximately 2 years later). All patients said they would undergo bronchoscopy again for diagnostic purposes (required in seven during the study). When compared to a healthy volunteer population within the same study, postbronchoscopy symptoms were similar in frequency although somewhat different in nature. Subjects felt that a clear explanation of what was involved enhanced their participation in this research. CONCLUSIONS: Invasive research procedures such as bronchoscopy can be performed and are repeatable in a healthy HIV-infected population. Performance of procedures for research purposes does not appear to adversely affect future health-care decisions.  相似文献   
179.
PURPOSE: To determine the accuracy of semiautomated quantification of articular cartilage volume from three-dimensional (3D) reformations of magnetic resonance (MR) images. MATERIALS AND METHODS: Sagittal, fat-suppressed, 3D, spoiled gradient-recalled-echo MR imaging of two bovine and two human cadaver knees was performed. Articular cartilage volume was calculated from 3D reformations of the MR images by using a semiautomated program written at the authors' institution. Calculated volumes were compared with directly measured volumes of the surgically removed articular cartilage. RESULTS: The percentage of error of the MR imaging-determined volumes was 6.53% +/- 4.75 (mean +/- standard deviation). A strong correlation between the two sets of observations was shown (r=.997). Linear regression showed the calculated volumes to be highly accurate (slope=1.002, P>.25). Repeated reformations yielded volumes that were reproducible (mean absolute error, 0.013 mL +/- 0.019) and not significantly different from the measured volume (P>.10). CONCLUSION: Semiautomated quantification of knee articular cartilage from MR images yields highly accurate cartilage volumes.  相似文献   
180.
BACKGROUND AND OBJECTIVE: Drug resistance has become a major cause of treatment failure in patients with acute leukemia. P-glycoprotein (Pgp), which is associated with the multidrug resistance (MDR) phenotype, has been reported to be an important predictor of treatment outcome. The aim of this study was to analyze the value of Pgp expression in bone marrow or peripheral blood as a predictor of the response to remission induction chemotherapy as well as the duration of remission in patients with de novo acute myeloid leukemia (AML). DESIGN AND METHODS: We examined the expression of Pgp in 82 patients with de novo AML using an immunocytochemical assay with the C219 monoclonal antibody. RESULTS: Twenty-seven of the 82 patients (33%) were C219-positive in from 1% to 100% of their cells. Thirteen cases (16%) showed a positive reaction in more than 50% of the leukemic cells. Only hyperleukocytosis was significantly associated with higher expression of Pgp. Although 8 of the 13 cases (62%) with more than 50% of cells having Pgp expression were CD34-positive, this association was not statistically significant. A univariate analysis of resistance to induction therapy showed a significantly higher resistance rate in patients with increased Pgp expression (P = 0.01) as well as in those patients with decreased reactivity to myeloperoxidase. The multivariate analysis revealed the independent prognostic value of Pgp expression. C219 reactivity did not have an influence on remission duration. INTERPRETATION AND CONCLUSIONS: Our data indicate that P-glycoprotein expression is a reliable marker of resistance to induction treatment in patients with de novo AML.  相似文献   
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