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991.
AIMS: To identify factors associated with receptive syringe sharing among injection drug users (IDUs) and elucidate the association between syringe possession arrests and syringe sharing. DESIGN: Cross-sectional study. SETTING: Mexican border cities of Tijuana, Baja California and Ciudad Juarez, Chihuahua. PARTICIPANTS: IDUs in Tijuana (n = 222) and Ciudad Juarez (n = 206) were recruited using respondent-driven sampling (RDS). IDUs were > or = 18 years and had injected illicit drugs in the past month. MEASUREMENTS: An interviewer-administered survey was used to collect quantitative data on socio-demographic, behavioral and contextual characteristics, including self-reported syringe sharing and arrests for syringe possession. Associations with receptive syringe sharing were investigated using logistic regression with RDS adjustment. FINDINGS: Overall, 48% of participants reported ever being arrested for carrying an unused/sterile syringe, even though syringe purchase and possession is legal in Mexico. Arrest for possessing unused/sterile syringes was associated independently with receptive syringe sharing [adjusted odds ratio (AOR) = 2.05; 95% confidence interval (CI): 1.26, 3.35], as was injecting in a shooting gallery (AOR = 3.60; 95% CI: 2.21, 5.87), injecting in the street (AOR = 2.05; 95% CI: 1.18, 3.54) and injecting methamphetamine (AOR = 2.77; 95% CI: 1.41, 5.47) or cocaine (AOR = 1.96; 95% CI: 1.15, 3.36). More than half of participants (57%) had been arrested for possessing a used syringe; in a second model, arrest for used syringe possession was also associated independently with receptive sharing (AOR = 2.87; 95% CI: 1.76, 4.69). CONCLUSIONS: We documented high levels of syringe-related arrests in two Mexican-US border cities and an independent association between these arrests and risky injection practices. Public health collaborations with law enforcement to modify the risk environment in which drug use occurs are essential to facilitate safer injection practices.  相似文献   
992.
OBJECTIVES: To compare subjective tolerance and secondary adverse events to bowel cleansing prior to colonoscopy with polyethylene glycol (PEG) and sodium phosphate (NaP) in adult patients and in those 65 or more years old. MATERIAL AND METHODS: Retrospective matched study, choosing 140 patients among all of those who underwent colonoscopy from March 2004 to May 2005. We investigated the presence of the next adverse events during bowel preparation: Fever, low digestive bleeding, abdominal pain, perianal pain, nausea, vomiting, thirst, somnolence, agitation, tremor and convulsions. We considered bad objective tolerance if the patient presented any one of these events. We also asked patients about subjective tolerance to preparation. RESULTS: Seventy patients prepared with PEG and seventy with NaP were included (69 women and 71 men, mean age 60.6 +/- 14.8 years). There was no relationship between subjective tolerance or the presence of adverse events and bowel cleansing with any of the products in general population or in elderly patients (p = 0.09 and p = 0.45 in the elderly). However, patients prepared with NaP showed more nausea than those who employed PEG (p < 0.009), overall women of 65 or more years old. There were no severe adverse events in patients prepared with NaP. Elderly showed better tolerance than younger patients, and women worst tolerance than men, irrespective of the lavage preparation employed. Patients prepared with PEG unfinished bowel cleansing more frequently than those with NaP. Cleanliness achieved with NaP was significantly better than that obtained with PEG. CONCLUSIONS: Bowel cleansing prior to colonoscopy with NaP is as well tolerated, safe and effective as with PEG, even in elderly healthy patients, although it causes more nausea. Cleanliness with NaP is better than that achieved with PEG.  相似文献   
993.
BACKGROUND: Patients with functional constipation presenting no response to treatment using fibers supplement represents important clinical issue. AIMS: To evaluate the relations among the amount of ingested fiber, the constipation intensity and the colonic transit time in patients with functional constipation. METHODS: We evaluated 30 patients, presenting no response to treatment using fibers supplement, and 18 healthy volunteers conducting individual inquiry into fibers intake, constipation intensity and the total and segmental colonic transit evaluation using radiopaque markers. RESULTS: In the constipated, despite the good level of fiber intake (26.3 +/- 12.9 g, constipated x 9.3 +/- 5,2 g, control), the symptoms of constipation was serious (score = 21.3 +/- 4.07). Mean total colonic transit was 58.8h. The colonic transit was slower in the constipated group (41.0 +/- 22.8 hours, constipated x 21.8 +/- 18.5h, control). In constipated patients with slow colonic transit (>58.8h) there were colonic inertia (eight), outlet constipation (one) and slow transit in left colon (one), and among constipated patients with normal colonic transit (<58.8h), there were isolated slow transit, in the right colon (nine), left colon (three) and in the rectosigmoid segment (eight). There were no relation among the amount of ingested fiber, constipation intensity and the colon transit. CONCLUSIONS: In the functional constipation the gravity of symptoms does not depend only on the dietary fibers intake, which is not the only responsible for the differences in the colonic transit. The colonic transit can differentiate normal from constipated patients and, among them, those with altered transit that demand approaches distinct of fiber supplementation.  相似文献   
994.
AIM: The aim of this study was to evaluate the pattern of undergraduate endodontic teaching in Philippine dental schools. METHODOLOGY: Data were gathered by sending questionnaires to the deans of the 23 dental schools in the country to determine details of the teaching of root canal treatment in permanent teeth. The covering letter requested that endodontic staff complete the questionnaire. RESULTS: Twenty of 23 dental schools returned completed questionnaires. Similarities were observed in the timing of undergraduate endodontic teaching, working length determination, and root canal preparation technique. Irrigating fluids recommended included one or a combination of the following: sodium hypochlorite, hydrogen peroxide, distilled water and EDTA. The root canal medicaments popularly employed were CMCP and eugenol. Most schools used slow-setting zinc oxide eugenol cement as sealer. Differences between schools were noted in the laboratory component of the course. The time allotted for the laboratory exercises, as well as the number of teeth used, differed greatly between each school. An inadequate tutor to student ratio was noted in the majority of schools. Teaching aids were limited and, in most instances, produced by faculty members. Most faculty members teaching endodontics had no specialist training. CONCLUSION: The results of this study have demonstrated that there is a need to review endodontic teaching in the majority of the Philippine dental schools to ensure that the course content and curriculum employed by all schools meet specified standards and that appropriate measures should be considered to enhance the learning experience of students.  相似文献   
995.
Biliary endoscopic drainage using metallic self-expanded stents has become a well-established method for palliative treatment of malignant biliary obstruction. However, its occlusion, mainly by tumor overgrowth, is still the main complication without a standard treatment. We here describe a new method of treatment for biliary metallic stent occlusion, through the echo guided biliary drainage. We present a 68-year-old patient with metastatic pancreatic cancer previously treated for jaundice with ERCP and self-expandable metallic stent insertion. Four weeks later, the patient developed jaundice and symptoms of gastric outlet obstruction. A new ERCP confirmed obstruction of the second portion of the duodenum, due to diffuse tumor growth. EUS was performed, and the previous metal biliary stent was seen occluded at the distal portion in the common bile duct. A EUS-guided choledocododenostomy was performed and then, an overlapping self-expanding metal enteral stent was placed through the malignant obstruction. There were no early complications and the procedure was also clinically effective in relieving jaundice and gastric outlet obstruction symptoms. If ERCP fails in the management of occluded biliary metallic stents, EUS biliary drain can provide effective biliary decompression and should be considered an alternative to other endoscopic techniques.  相似文献   
996.
Systolic blood pressure (SBP) is a more frequent cardiovascular risk factor than diastolic blood pressure (DBP), and has a greater impact on blood pressure staging, though this can vary with age, sex and country. Therefore this paper compares SBP and DBP in terms of community burden and impact on blood pressure staging, among Spain's middle-aged population. Data were drawn from a cross-sectional study on a representative sample of the Spanish population aged 35-64 years. Blood pressure was determined under standardised conditions, and was classified as per WHO-ISH and JNC-VI criteria. Prevalence of SBP > or =140 mm Hg was 34.1%, and that of DBP > or =90 mm Hg, 30.9%. A total of 12% of subjects had isolated systolic hypertension (ISH) and 8.7% had isolated diastolic hypertension (IDH). Of treated hypertensives, 31% had their SBP controlled and 34% their DBP controlled. Of subjects not undergoing antihypertensive drug therapy, 60.8% had congruent SBP and DBP levels, 22.5% were up-staged on the basis of their SBP, and 16.7% were up-staged on the basis of their DBP. SBP alone thus correctly classified JNC-VI staging in 83.3% of subjects vs 77.5% for DBP alone. It was solely among the population >50 years of age, in both sexes, that systolic proved more frequent than diastolic hypertension, ISH greater than IDH prevalence, SBP worse than DBP control, and the percentage of SBP higher than that of DBP up-staged subjects. SBP constitutes a greater community burden than does DBP, and has a greater impact on blood pressure staging in Spain's middle-aged population. However, the differential impact of SBP and DBP upon blood pressure burden and staging is favourable to SBP only among subjects >50 years old. These findings are in accordance with recent guidelines on hypertension management.  相似文献   
997.

Background  

The 23-valent polysaccharide pneumococcal vaccine (PPV) is currently recommended in elderly and high-risk adults. However, its efficacy in preventing pneumococcal infections remains controversial. This study assessed the clinical effectiveness of vaccination against invasive pneumococcal disease (IPD) among people over 60 years.  相似文献   
998.
We aimed to estimate the prevalence of resistant hypertension through both office and ambulatory blood pressure monitoring in a large cohort of treated hypertensive patients from the Spanish Ambulatory Blood Pressure Monitoring Registry. In addition, we also compared clinical features of patients with true or white-coat-resistant hypertension. In December 2009, we identified 68 045 treated patients with complete information for this analysis. Among them, 8295 (12.2% of the database) had resistant hypertension (office blood pressure ≥140 and/or 90 mm Hg while being treated with ≥3 antihypertensive drugs, 1 of them being a diuretic). After ambulatory blood pressure monitoring, 62.5% of patients were classified as true resistant hypertensives, the remaining 37.5% having white-coat resistance. The former group was younger, more frequently men, with a longer duration of hypertension and a worse cardiovascular risk profile. The group included larger proportions of smokers, diabetics, target organ damage (including left ventricular hypertrophy, impaired renal function, and microalbuminuria), and documented cardiovascular disease. Moreover, true resistant hypertensives exhibited in a greater proportion a riser pattern (22% versus 18%; P<0.001). In conclusion, this study first reports the prevalence of resistant hypertension in a large cohort of patients in usual daily practice. Resistant hypertension is present in 12% of the treated hypertensive population, but among them more than one third have normal ambulatory blood pressure. A worse risk profile is associated with true resistant hypertension, but this association is weak, thus making it necessary to assess ambulatory blood pressure monitoring for a correct diagnosis and management.  相似文献   
999.
We assessed the performance characteristics of two rK39 immunochromatographic tests, a direct agglutination test (DAT), and an indirect immunofluorescent antibody test (IFAT) in the site of a new epidemic of visceral leishmaniasis (VL) in northwestern Ethiopia. The study population was composed of 179 patients with suspected VL and 67 controls. The sensitivities of Kalazar Detect®, DiaMed-IT Leish®, DAT, and IFAT in 35 polymerase chain reaction–confirmed VL cases were 94.3%, 91.4%, 91.4%, and 100%, respectively, and the specificities were 98.5%, 94%, 98.5%, and 98.5%, respectively. In a Bayesian latent class analysis of all 246 specimens, the estimated sensitivities were 90.5%, 89%, 88.8%, and 96% for Kalazar Detect®, DiaMed-IT Leish®, DAT, and IFAT, respectively; DAT showed the highest estimated specificity (97.4%). Both rK39 immunochromatographic tests perform as well as DAT, and are suitable for VL diagnosis in first-level health centers in this area of Ethiopia.  相似文献   
1000.
Abstract: Pancreatic cancer is a major health problem because of the aggressiveness of the disease and the lack of effective systemic therapies. Melatonin (MEL) has antioxidant activity and prevents experimental genotoxicity. The specific inhibitor of cyclooxygenase‐2 (COX‐2), celecoxib (CEL), increases the efficacy of chemoradiotherapy in advanced pancreatic cancer. The objective of the study was the comparison and synergic effect of MEL and CEL during either the induction or progression phases of the tumor process, measuring parameters of oxidative stress, number of tumor nodules and survival of animals with pancreatic cancer. Pancreatic cancer was induced by N‐nitrosobis (2‐oxopropyl)amine) (BOP) in Syrian hamsters. Melatonin and/or CEL were administered during the induction, postinduction as well as during both phases. The presence of tumor nodules were observed macroscopically in pancreatic and splenic areas, and the levels of lipoperoxides (LPO), reduced glutathione (GSH), superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GSH‐Px) in pancreatic tissue were measured. The increases in tumor nodules and LPO as well as the reductions in GSH and enzymatic antioxidants in the pancreas induced by BOP were related to a lower survival rate of animals. The administration of MEL exerted a more potent beneficial effect than CEL treatment on the reduction in tumor nodules, oxidative stress and death of experimental BOP‐treated animals. The combined treatment only exerted a synergistic beneficial effect when administered during the induction phase. Melatonin by itself had significant beneficial actions in improving the survival of hamsters.  相似文献   
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