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101.
Effect of age and malnutrition on rotavirus infection in mice   总被引:1,自引:0,他引:1  
Litters of malnourished and normally nourished suckling mice of various ages were fed mouse rotavirus (10(5) ID50). Infection was monitored by immunofluorescent staining of isolated epithelial enterocytes 24, 28, and 72 h after virus ingestion; enzyme linked immunosorbent assay of daily fecal samples; and determining the severity of diarrhea by noting the color and consistency of the feces and the presence or absence of staining. In malnourished mice 5 to 9 days old, all the parameters of infection were significantly greater than in their normally nourished counterparts. However, in mice 10 to 14 days old the differences in extent and severity of infection in malnourished and normally nourished animals was not significant. After 15 days of age there were low levels of virus shedding and antigen-positive enterocytes in both malnourished and normally nourished animals, but there was no diarrhea in either group. Therefore it appears that nutritional manipulation, resulting in malnutrition, does not alter the state of refractoriness to symptomatic rotavirus infection in mice greater than 15 days old.  相似文献   
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103.
This study measured the responses of 17 cancer hospice patients to humidified essential lavender oil aromatherapy. Vital signs as well as levels of pain, anxiety, depression, and sense of well-being were measured (using 11-point verbal analogs). Each subject was measured on three different days before and after a 60-minute session consisting of (1) no treatment (control); (2) water humidification (control); or (3) 3-percent lavender aromatherapy. Results reflected a positive, yet small, change in blood pressure and pulse, pain, anxiety, depression, and sense of well-being after both the humidified water treatment and the lavender treatment. Following the control session (no treatment), there was also slight improvement in vital signs, depression, and sense of well-being, but not in pain or anxiety levels.  相似文献   
104.
Kowalski LP  Carvalho AL 《Head & neck》2002,24(10):921-924
BACKGROUND: The use of selective neck dissection in a positive neck is still controversial. The object of this study was to ascertain the possibility of doing this procedure in oral cavity carcinoma with a single clinically metastatic lymph node smaller than 6 cm (N1 and N2a). PATIENTS AND METHODS: From 1970 to 1994, we analyzed 164 oral cavity cancer patients with clinically N1 or N2a stage cancer submitted to radical neck dissection. RESULTS: The histologic findings did not confirm a metastatic lymph node in 69 (42.1%) cases (pN0) and showed multiple lymph nodes in 19 (11.6%) cases. Moreover, just one patient (0.6%) had a metastatic lymph node at level IV (one case with multiple lymph nodes) and none at level V. CONCLUSIONS: Because we did not find a single metastatic lymph node at levels IV and V and there was a high incidence of pN0 (57.4%) in patients with clinical N1 stage at level I, these patients could be candidates for a supraomohyoid neck dissection (extended or not to level IV) instead of radical neck dissection.  相似文献   
105.
OBJECTIVE: To evaluate the effect of a short period of mechanical ventilation (3 hours) versus immediate extubation (within 1 hour of surgery) on pulmonary function, gas exchange, and pulmonary complications after coronary artery bypass graft (CABG) surgery. DESIGN: Prospective randomized study. SETTING: University teaching hospital. PARTICIPANTS: Thirty-five patients undergoing CABG surgery. INTERVENTIONS: Patients were randomized into 2 groups. Patients in group I were extubated as soon as possible after surgery. Patients in group II were ventilated for a minimum of 3 hours after surgery. Patients in both groups were extubated only after achieving predetermined extubation criteria. Patients who did not meet the criteria for extubation within the predetermined set time limit (90 minutes in group I and 6 hours in group II) were withdrawn from the study. Pulmonary function tests (vital capacity, forced expiratory volume in 1 second, total lung capacity, functional residual capacity), arterial blood gases, and chest radiographs were done preoperatively and postoperatively. Pulmonary complications were recorded. MEASUREMENTS AND MAIN RESULTS: Demographic data were similar between groups. The mean time to extubation in group I was 45.7 plus minus 27.6 minutes and in group II was 201.4 plus minus 21 minutes (p < 0.01). Two patients in group I and 1 patient in group II did not meet the extubation criteria within the predetermined set time limit and were excluded from the study. In both groups, there was a significant decline in pulmonary function but no differences between groups at 24 or 72 hours after surgery. There were no differences between groups in blood gases, atelectasis scores, or pulmonary complications. CONCLUSION: The data suggest that extending mechanical ventilation after CABG surgery does not affect pulmonary function. Provided that routine extubation criteria are met, patients can be safely extubated early (within 1 hour) after major cardiac surgery without concerns of further pulmonary derangement.  相似文献   
106.
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108.
In this study, we compared the relative abilities of human thymidylate synthase (hTS) and Escherichia coli thymidylate synthase (eTS) expression to confer resistance to the cytotoxic effects of treatment with the TS inhibitor 5-fluorodeoxyuridine (FdUrd). G418-selected clones expressing either form of the protein were significantly more resistant than the lacZ-expressing clone, VALZ2, to FdUrd-induced cytotoxicity. Although eTS-expressing clones expressed 2- to 3-fold more TS protein than hTS-overexpressing clones, the representative eTS-expressing clone, VAEG8, and hTS-overexpressing clone, VAHGC, were equally sensitive to an FdUrd-induced loss of clonogenicity; in addition, a large fraction of either form of exogenously expressed TS appeared to be inactive in the intact cell. The clones differed, however, in their responses to leucovorin (LV). Although LV significantly enhanced FdUrd-induced TS inhibition, growth inhibition, and cytotoxicity in VAHGC cells, it had no effect on these parameters in VAEG8 cells. These results suggest that eTS may more efficiently confer resistance to FdUrd plus LV when expressed for the purposes of a "host protection" strategy in vivo.  相似文献   
109.
A low level of serum pepsinogen I (Pg I) is a risk factor for gastric cancer (GC); low levels of Pg I and the pepsinogen ratio (Pg I:Pg II) are correlated with chronic atrophic gastritis. We report serum Pg levels and compare the degree of association with GC among Japanese and non-Japanese Brazilians. Sera were cross-sectionally ascertained from 93 Japanese Brazilian patients category matched by age and sex with 110 controls, and 228 non-Japanese Brazilian patients individually matched by age and sex with one control. Among non-Japanese Brazilians, GC was associated with a Pg I level <30 ng/ml (odds ratio [OR], 2.5; 95% confidence interval [CI], 1.7-3.8) and a Pg I:Pg II ratio < 3.0 (OR, 3.4; 95% CI, 2.2-5.3). However, among Japanese Brazilians, the association was present with a level of Pg I < 30 ng/ml (OR, 3.5; 95% CI, 1.9-6.3), and was weak with a Pg I:Pg II ratio < 3.0 (OR, 1.3; 95% CI, 0.73-2.4). Serum Pg I may be preferred to the Pg I:Pg II ratio to study the association between Pg and GC among Japanese Brazilians.  相似文献   
110.
A variety of methods that address the detection of single-nucleotide polymorphism (SNP) have been used in molecular diagnostics. The allele-specific polymerase chain reaction (ASPCR) has been one of the most extensively studied, including its application in the tumor necrosis factor (TNF)(-308) genotyping. Many studies have demonstrated that the ASPCR sensitivity and specificity depends on various PCR parameters, with mismatches occurring to a degree of 4%. The purpose of our study was to evaluate a comparison of genotyping of the TNF(-308) using an ASPCR and automated sequencing (ASEQ). In a total of 204 DNA samples, their duplicate examination by the ASPCR and ASEQ revealed concordant results in 96.5% and mismatches in 3.5% genotypes. Depending on the target TNF(-308G/G), TNF(-308G/A) , TNF(-308A/A) sequences, this translated into decreased ASPCR sensitivity to a degree of 98.6%, 94.2%, 60.0%, specificity 94.7%, 97.4%, 100.0%, positive predictive values 97.9%, 92.5%, 100.0%, and negative predictive values 96.4%, 98.0%, 99.0%, respectively. Based on these results, we found ASEQ to be more accurate than ASPCR for the TNF(-308) genotyping. By eliminating the need of empirical determination of appropriate PCR conditions for each studied sequence, ASEQ provides a sensitive and reproducible quality-control benchmark for other SNP assays.  相似文献   
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