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21.
BACKGROUND: A surveillance system was established at the Aga Khan University Hospital in Karachi, Pakistan, to determine surgical wound infection (SWI) rates, trends, and risk factors; and to compare rates with those reported by the National Nosocomial Infection Surveillance (NNIS) system of the Centers for Disease Control and Prevention. METHODS: Surveillance was performed from January 1997 to December 1999. Risk categorization was on the basis of the NNIS system. P <.05 was set for statistically significant difference between groups. Data were analyzed using the Epi-Info software (version 6.04, CDC, Atlanta, Ga). RESULTS: Overall SWI rates for the NNIS risk categories 0, 1, 2, and 3 were 1.9%, 3.7%, 6.7%, and 5.1%, respectively. SWI rate in 0 risk category decreased from 3% in 1997 to 1.1% in 1999 (P =.06). Multivariate analysis showed that SWI rates were higher after mastectomy (odds ratio [OR] 4.28, 95% confidence interval [CI] 1.8-10), hernia repair (OR 3.28, 95% CI 1.6-6.7), gastrointestinal resection (OR 2.2, 95% CI 0.88-5.9), skin procedures (OR 1.97, 95% CI 0.89-4.3), appendectomy OR 0.57, 95% CI 0.20-1.60, and miscellaneous procedures (OR 3.6, 95% CI 1.6-7.7), as compared with cholecystectomy. Other risk factors were contaminated type of operation (OR 2.6, 95% CI 1.2-5.5), and duration of operation exceeding the NNIS standard of "T" hours (OR 2.6, 95% CI 1.7-4). CONCLUSION: The SWI rates at the Aga Khan University Hospital are higher than the NNIS standards. There was a downward trend in the SWI rates during the surveillance period. A decrease in the duration of surgical procedures could further reduce the risk.  相似文献   
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Several DNA probes were designed for use in real-time polymerase chain reaction (PCR) assays to target sequence variation within the ribosomal intergenic spacer (IGS) of schistosomes. A sub-section of the IGS (∼300 bp) was amplified, with cross-specific primers, after which group-specific fluorescent, locked nucleic acid probes were assessed for their ability to differentiate and quantify DNA from Schistosoma haematobium and Schistosoma mansoni group parasites. A number of fluorescent probe candidates were screened and validated against genomic DNA from adult schistosome worms and laboratory infected freshwater snails. Two fluorescent, locked nucleic acid probes ShaemLNA5 and SmanLNA2, of 20–26 bp in length, were identified and found to be effective in providing evidence of infection in field-collected snails. To adapt these real-time PCR assays for more resource-poor laboratory settings, a PCR-restriction fragment length polymorphism (RFLP) assay was developed and primer/probe combinations were modified for use in oligochromatography, a DNA ‘dipstick’ technology. An appropriate dipstick was developed, inclusive of internal amplification and amplicon migration controls that could be of particular importance for assessing schistosome transmission dynamics. These assays and tools also have future potential for use in detection of schistosome infections in humans and livestock.  相似文献   
23.
MS has been hypothesized to result from autoreactive T cell responses against myelin antigens. In this report, we examined myelin-specific CD8 and CD4 T cells for two markers differentially expressed on na?ve, memory and chronically stimulated T cells, CD28 and CD57. We observed differential expression on CD8 T cells in response to myelin antigens, but not in response to the recall antigen mumps. We demonstrate these cells display reduced proliferation and this may explain why therapies that limit the proliferation of T cells have had little effect on the course of MS, particularly later in the course of the disease.  相似文献   
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Tuberculosis (TB) is a global issue as one‐third of the population worldwide is considered to be infected. TB has become a critical public health problem as a result of increasing drug resistance, which poses a challenge to current control strategies. Similar to environmental factors, genetic makeup of the host equally contributes to disease onset. We performed genotypic analysis to examine the relationship between IFNG and TB onset and drug resistance in a Pakistani population comprising 689 subjects. Notable differences were observed in the IFNG polymorphism (+874T/A) between the case and control groups. The frequency of the wild‐type genotype (TT) in the controls (43.2%) was significantly higher than in the cases (25.3%) (odds ratio [OR] = 0.77, p < 0.0001), while the mutant genotype frequency (AA) (38.57%) in the cases was significantly higher than in the controls (22.6%) (OR = 1.46, p < 0.0001). The heterozygous genotype frequency (TA) did not significantly differ between the control and case groups. Compared with the controls, the variant allele (A) was approximately twice as frequent in the cases. Females and older people have a higher chance of disease development. Finally, the IFNG (+874T/A) polymorphism was not associated with drug sensitivity or resistance. However, a genotypic polymorphism of IFNG (+874T/A) was significantly associated with susceptibility to TB, and the T allele conferred protection against TB. Additional studies involving larger cohorts are needed to further explore this relationship between genetics and disease vulnerability.  相似文献   
26.
BACKGROUND: This randomized controlled trial assessed the safety and effects of twice-weekly weight training among recent breast cancer survivors. Outcomes included body size and biomarkers hypothesized to link exercise and breast cancer risk. METHODS: A convenience sample of 85 recent survivors was randomized into immediate and delayed treatment groups. The immediate group trained from months 0 to 12; the delayed treatment group served as a no exercise parallel comparison group from months 0 to 6 and trained from months 7 to 12. Measures at baseline, 6 and 12 months included body weight, height, body fat, lean mass, body fat %, and waist circumference, as well as fasting glucose, insulin, insulin resistance, insulin-like growth factor-I (IGF-I), IGF-II, and IGF-binding protein-1, IGFBP-2, and IGFBP-3. Injury reporting was standardized. RESULTS: The intervention resulted in significant increases in lean mass (0.88 versus 0.02 kg, P < 0.01), as well as significant decreases in body fat % (-1.15% versus 0.23%, P = 0.03) and IGF-II (-6.23 versus 28.28 ng/mL, P = 0.02) comparing immediate with delayed treatment from baseline to 6 months. Within-person changes experienced by delayed treatment group participants during training versus no training were similar. Only one participant experienced a study related injury that prevented continued participation. CONCLUSION: Twice-weekly weight training is a safe exercise program for recent breast cancer survivors that may result in increased muscle mass, as well as decreased body fat % and IGF-II. The implications of these results on cancer recurrence or survival may become more evident with longer exercise intervention trials among breast cancer survivors.  相似文献   
27.
Objective. To fill the gap in grant writing training in pharmacologygraduate education using an active-learning strategy.Design. Graduate students wrote subsections of a grant according to NIHguidelines. Students revised their applications based on multiple rounds of critiquesfrom professors and peers throughout a semester-long scientific writing course.Assessment. Prerevision and postrevision grant drafts were graded.Students were provided with questionnaires assessing their perception of the process.To determine the impact of feedback on the proposals, the quality of thepre/postrevision drafts was assessed by professors who were blinded and unaffiliatedwith the course.Conclusion. Student grades improved significantly upon resubmission.Perceptions of the proposals by blinded faculty members favored revised submissionsbased on multiple criteria. Survey feedback indicated an increase in studentconfidence in grant writing ability. The results of 3 independent measuresdemonstrate that intensive feedback on scientific writing improved the quality ofstudent proposals.  相似文献   
28.
The aim of this study was to evaluate the impact of a twice-weekly strength training intervention on perceptions of body image in 234 breast cancer survivors (112 with lymphedema) who participated in the Physical Activity and Lymphedema (PAL) trial. The study population included two hundred and thirty-four women randomly assigned to twice-weekly strength training or control group that completed the 32-item Body Image and Relationships Scale (BIRS) at baseline and 12 months. Percent change in baseline to 12-month BIRS total and subscale scores, upper and lower body strength, and general quality of life (QOL) were compared by intervention status. A series of multiple linear regression models including indicator variables for subgroups based on age, marital status, race, education, BMI, and strength change were used to examine differential intervention impact by subgroup. Strength and QOL variables were assessed as mediators of the intervention effect on BIRS. Results: Baseline BIRS scores were similar across intervention and lymphedema status. Significantly greater improvement in BIRS total score was observed from baseline to 12 months in treatment vs. control participants (12.0 vs. 2.0%; P < 0.0001). A differential impact of the intervention on the Strength and Health subscale was observed for older women (>50 years old) in the treatment group (P = 0.03). Significantly greater improvement was observed in bench and leg press among treatment group when compared to control group participants, regardless of lymphedema. Observed intervention effects were independent of observed strength and QOL changes. Twice-weekly strength training positively impacted self-perceptions of appearance, health, physical strength, sexuality, relationships, and social functioning. Evidence suggests the intervention was beneficial regardless of prior diagnosis of lymphedema. Strength and QOL improvements did not mediate the observed intervention effects.  相似文献   
29.
Metal–organic framework (MOFs) based composites have received more research interest for photocatalytic applications during recent years. In this work, a highly active, visible light photocatalyst BiOBr/UiO-66-NH2 hybrid composite was successfully prepared by introducing various amounts of UiO-66-NH2 with BiOBr through a co-precipitation method. The composites were applied for the photocatalytic degradation of RhB (rhodamine B) dye. The developed BiOBr/UiO-66-NH2 composites exhibited higher photocatalytic activity than the pristine material. In RhB degradation experiments the hybrid composite with 15 wt% of UiO-66-NH2 shows degradation efficiency conversion of 83% within two hours under visible light irradiation. The high photodegradation efficiency of BUN-15 could be ascribed to efficient interfacial charge transfer at the heterojunction and the synergistic effect between BiOBr/UiO-66-NH2. In addition, an active species trapping experiment confirmed that photo-generated hole+ and O2 radicals are the major species involved in RhB degradation under visible light.

Metal–organic framework (MOFs) based composites have received more research interest for photocatalytic applications during recent years.  相似文献   
30.
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