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21.
ObjectiveTo screen for Escherichia coli (E. coli) resistant to tetracycline, followed by identification of tet efflux genes by polymerase chain reaction (PCR). In addition, detection of tetracycline residues in chicken livers and kidneys were conducted using high performance liquid chromatography-tandem quadrupole mass spectrometry (HPLC-MS-MS).MethodsStrains of E. coli were isolated from samples of chicken colon and screened for tetracycline resistance. Tetracycline genes conferring resistance (Tcr) were detected by polymerase chain reaction (PCR). Most of the isolates were resistant to tetracycline (97.9%).ResultsPCR analysis indicated that Tcr E. coli R-plasmids contained tet(A), tet(B) and a combination of both efflux genes. None of the isolates contained other efflux tet genes tet (C, D, E and Y). High performance liquid chromatography-tandem quadrupole mass spectrometry (HPLC-MS-MS), a sensitive technique, was used to detect residues of chlortetracycline (CTC), oxytetracycline (OTC), doxycycline (DC) in chicken livers and kidneys. The samples containing tetracycline residues were at 0.13-0.65 pg/μL levels.ConclusionsTetracycline and other antibiotics are commonly used in the poultry and meat production industry for prevention of microbial infections. Multiple antibiotic resistant bacteria in Oman have increased to alarming levels, threatening public health, domestic and may have adverse effect on environment.  相似文献   
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The purpose of this study was to compare the effects of yoga with an active control (nonaerobic exercise) in individuals with prehypertension and stage 1 hypertension. A randomized clinical trial was performed using two arms: (1) yoga and (2) active control. Primary outcomes were 24‐hour day and night ambulatory systolic and diastolic blood pressures. Within‐group and between‐group analyses were performed using paired t tests and repeated‐measures analysis of variance (time × group), respectively. Eighty‐four participants enrolled, with 68 participants completing the trial. Within‐group analyses found 24‐hour diastolic, night diastolic, and mean arterial pressure all significantly reduced in the yoga group (?3.93, ?4.7, ?4.23 mm Hg, respectively) but no significant within‐group changes in the active control group. Direct comparisons of the yoga intervention with the control group found a single blood pressure variable (diastolic night) to be significantly different (P=.038). This study has demonstrated that a yoga intervention can lower blood pressure in patients with mild hypertension. Although this study was not adequately powered to show between‐group differences, the size of the yoga‐induced blood pressure reduction appears to justify performing a definitive trial of this intervention to test whether it can provide meaningful therapeutic value for the management of hypertension.  相似文献   
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BACKGROUND: The combined treatment of sustained-release basic fibroblast growth factor (Sr-bFGF) and a 5-hydroxytryptamine(2A) blocker, sarpogrelate, was evaluated to see whether it reversed the impaired collateral circulation in diabetic (DM) mouse hindlimb ischemia. METHOD AND RESULTS: Diabetic and normal mice with ischemic hindlimb were randomly assigned to 1 of 5 experimental groups (no treatment, sarpogrelate 50 mg . kg(-1) . day(-1), 20 microg or 50 microg Sr-bFGF and a combined treatment of 20 microg Sr-bFGF and sarpogrelate), and treated for 4 weeks. Tissue blood perfusion (TBP), vascular density (angiogenesis) and the number of mature vessels (arteriogenesis) were checked by the use of standard methods. Although angiogenesis was comparable (161+/-14 vs 154+/-12 vessels/mm(2)), the laser Doppler perfusion image index (LDPII) (0.43+/-0.11 (SD) vs 0.63+/-0.08, p<0.05) and arteriogenesis (8+/-3 vs 12+/-4 vessels/mm(2), p<0.05) were significantly lower in DM mice than those in normal mice. The dose of Sr-bFGF for the sufficient number of mature vessels (>or=45 vessels/mm(2)) and LDPII (>or=0.9) was 20 microg for the normal mice, and 50 microg for the DM mice, which was reduced with the aid of sarpogrelate. Conclusions A combined therapy of Sr-bFGF and sarpogrelate is effective for neovascularization to reverse the impaired arteriogenesis and TBP in DM mice.  相似文献   
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Formal assessment of cognitive decline with cognitive tests can be difficult, requiring either two measurement points or a comparison of 'hold' with 'don't hold' tests. Informant-based assessment provides an alternative approach because informants can adopt a longitudinal perspective and directly rate cognitive change. A study was carried out to assess the validity of informant ratings collected by means of the Informant Questionnaire on Cognitive Decline in the Elderly (IQCODE). A community sample of 500 subjects aged 74 or over underwent four cognitive tests on two occasions 3½ years apart. On the second occasion, informants filled out the IQCODE. Subjects rated as having moderate or severe decline were found to have greater change on the cognitive tests. These findings support the validity of informant ratings of cognitive decline.  相似文献   
28.

Aim

To determine long-term outcome of endoscopic management of pancreatic pseudocyst/walled-off pancreatic necrosis (WOPN) without necrosectomy.

Methods

One-hundred and sixty-five pancreatic pseudocysts/WOPN managed endoscopically over a period of 22 years were analyzed retrospectively for technical success, complications, and recurrence.

Results

Symptomatic 118 males and 47 females with mean age of 35.8 years were included. Alcohol was the most common etiology (41.2 %). Transmural endoscopic drainage was done in 144 patients, while 21 patients underwent transpapillary drainage. All the patients were subjected to contrast computed tomography (CT) abdomen or routine/Doppler ultrasound. Endoscopic ultrasound was done in last 11 patients. One or two double pigtail 7 Fr stents were placed when clear watery fluid came out from cyst (130 patients, 78.8 %), and nasocystic drainage (NCD) tubes were placed in addition to two 7 Fr stents when there were frank pus, thick dark fluid, or solid components inside the cyst (35 patients). All these patients settled on this treatment. Thirty-three of 35 patients of WOPN could be managed endoscopically without necrosectomy. Complications occurred in 9.2 % of pseudocysts and 40 % of WOPN. Thirty-five patients were followed up for more than 5 years (3 patients more than 10 years), and 130 patients were followed up for up to 5 years. Recurrence occurred in 8.1 % of pseudocysts and 5.7 % of WOPN.

Conclusion

Majority of pancreatic pseudocysts/WOPN can be managed with endoscopic drainage without necrosectomy with high success, low complication, and recurrence rates.
  相似文献   
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A factor that augmented the phagocytosis of IgG-coated ox red blood cells by the human monocyte/macrophage line U937 was identified in cell culture supernatants from two of two patients with angiocentric peripheral T cell lymphomas, three of three patients with angiocentric immunoproliferative lesions that were not frankly malignant, and one of two patients with T lymphoblastic malignancies. The factor was not present in supernatants derived from 14 nonangiocentric peripheral T cell lymphomas of other histologic types nor in ten cases of B cell lymphoma and two cases of Hodgkin's disease. A similar factor was present in the supernatants of concanavalin A (Con A)-stimulated normal peripheral blood mononuclear cells and in the supernatants of IL-2- dependent T cell lines derived from normal peripheral blood. The factor had an apparent mol wt of greater than 50,000 daltons, was heat labile (100 degrees C for two minutes), and stable at pH 2.0. Its stimulation of phagocytosis was independent of any increase in number of Fc receptors. Thus, this factor is probably not gamma-interferon. This factor may play a pathogenetic role in the hemophagocytic syndromes associated with certain T cell malignancies and immunodeficient states.  相似文献   
30.
The B-lymphocyte/accessory-cell activation antigen B7 (BB1) has been shown in vitro to stimulate T-lymphocyte proliferation and cytokine production via CD28 present on the latter cells. In this study, benign lymphoid tissues, lymphomas, and extralymphoid inflammatory sites were examined immunohistochemically using anti-B7 and other relevant monoclonal antibodies. B7 was expressed by benign transformed germinal center B cells, as it was by B cells of follicular lymphomas. B7 was also expressed by a subpopulation (a mean of 31% to 65%) of macrophages and dendritic cells in a variety of lymphoid tissues. It was present in abundance on all macrophages constituting sarcoid granulomas in lymph nodes. In extralymphoid inflammation, 17% to 35% of macrophages expressed B7 only weakly. Cases of Hodgkin's disease showed expression of B7 by the majority of Reed-Sternberg cells or malignant mononuclear variants, a phenomenon that potentially contributes to the lymphocytic accumulation that is a feature of this condition. CD28+ T cells were seen in all areas where T cells were present. B7+ and CD28+ cells colocalized in, for example, lymphoid follicles, lymph node paracortex, sarcoid granulomas, and Hodgkin's disease tissue, indicating a potential for cellular interaction via these molecules at these sites.  相似文献   
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