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991.
992.
Optimal treatment for HIV-related visceral leishmaniasis (VL) has still to be established. A pilot clinical trial was carried out in 57 HIV-VL coinfected patients to compare the efficacy and safety of amphotericin B lipid complex (ABLC) versus meglumine antimoniate. The patients were randomized to receive either ABLC 3 mg/kg/day for 5 days (ABLC-5, 18 patients), ABLC 3 mg/kg/day for 10 days (ABLC-10, 20 patients) or meglumine antimoniate 20 mg Sbv /kg/day for 28 days (19 patients). Treatment was considered successful if parasites were not detected in a bone marrow aspirate after treatment. Parasitological cure was attained in 33% (95% CI: 13%-59%) of the ABLC-5 group, in 42% (95% CI: 16%-62%) of the ABLC-10 group and in 37% (95% CI: 16%-62%) of the meglumine antimoniate group (P = 0.94). Eight out of 19 patients administered antimoniate discontinued treatment prematurely following serious adverse events, compared with one in the ABLC groups (P = 0.0006). The efficacy of ABLC is similar to meglumine antimoniate, but the severity of toxicity in the treatment of HIV-VL is lower with ABLC.  相似文献   
993.
OBJECTIVE: To describe the tuberculosis morbidity and mortality trends in Mexico, by comparing the data reported by the Ministry of Health (MH) and the World Health Organization (WHO) between 1981 and 1998. MATERIAL AND METHODS: The number of cases notified in the past few years, their rates, and the trends of the disease in Mexico were analyzed. The incidence of smear-positive pulmonary tuberculosis was estimated for 1997 and 1998 with the annual tuberculosis infection risk (ATIR), to estimate the percentage of bacilliferous cases in 1997-1998. RESULTS: WHO reported more tuberculosis cases for Mexico than the MH. However, this difference has decreased throughout the years. The notification of smear-positive cases remained stable during 1993-1998. The estimated percentages of detection were 66% for 1997 and 26% for 1998 (based on ATIR of 0.5%). Tuberculosis mortality decreased gradually (6.7% per year) between 1990 and 1998, whereas the number of new cases increased, suggesting the persistence of disease transmission in the population. CONCLUSIONS: Inconsistencies between case notifications from national data and WHO were considerable, but decreased progressively during the study period. According to ATIR estimations, a considerable number of infectious tuberculosis cases are not detected. The English version of this paper is available at: http://www.insp.mx/salud/index.html.  相似文献   
994.
995.
For travelers malaria represents the principal infectious risk of severe complications and death. Infection during traveling depends on the geographical area visited, the predominant species of parasite, the frequency of resistance to antimalarial agents, and whether preventive measures have been taken. Until a vaccine has been developed, prevention strategies consist of providing travelers with information, the use of barrier methods against vector bites, the correct use of chemoprophylaxis, and the possibility of self-diagnosis and treatment. The choice of chemoprophylaxis regimen should be individualized since no regimen guarantees 100% protection or is free of adverse effects or contraindications. The most effective drugs are doxycycline, atovaquone-proguanil and mefloquine while those producing severe adverse effects with the least frequency are atovaquone-proguanil and doxycycline.  相似文献   
996.
Treatment with beta-blockers fails to decrease portal pressure in nearly 40% of cirrhotic patients. Recent studies have suggested that treatment with spironolactone reduces pressure and flow in the portal and variceal systems. This trial was designed to assess if nadolol plus spironolactone is more effective than nadolol alone to prevent the first variceal bleeding. One hundred patients with medium and large varices who had never bled and were without ascites were included in a prospective, randomized, multicenter, double-blind, placebo-controlled trial. The patients were randomized into 2 groups: 51 received nadolol plus placebo (N + P) and 49 received nadolol plus spironolactone 100 mg/d (N + S). Hepatic venous pressure gradient (HVPG) and activity of the renin-aldosterone system (plasma renin activity/plasma aldosterone levels) were measured in 24 patients. There were no significant differences in the appearance of variceal bleeding and ascites between groups at a mean follow-up of 22 +/- 16 months. However, analyzing both complications together, the incidence was significantly higher in the N + P group than in the N + S group (39% vs. 20%; P <.04). Clinical ascites was also higher in patients in the N + P group than in the N + S group (21% vs. 6%; P <.04). Significant increases in plasma renin activity and plasma aldosterone levels were only observed in patients in the N + S group (P <.01). The cumulative probabilities of remaining free of bleeding and ascites were similar in both groups after 70 months of follow-up. In conclusion, these results suggest that nadolol plus spironolactone does not increase the efficacy of nadolol alone in the prophylaxis of the first variceal bleeding. However, when bleeding and ascites were considered together, the combined therapy effectively reduced the incidence of both portal-hypertensive complications.  相似文献   
997.
The smallpox virus is a high-priority, Category-A agent that poses a global, terrorism security risk because it: (1) easily can be disseminated and transmitted from person to person; (2) results in high mortality rates and has the potential for a major public health impact; (3) might cause public panic and social disruption; and (4) requires special action for public health preparedness. In recognition of this risk, the Los Angeles County Department of Health Services (LAC-DHS) developed the Smallpox Preparedness, Response, and Recovery Plan for LAC to prepare for the possibility of an outbreak of smallpox. A unique feature of the LAC-DHS plan is its explicit use of the Standardized Emergency Management System (SEMS) framework for detailing the functions needed to respond to a smallpox emergency. The SEMS includes the Incident Command System (ICS) structure (management, operations, planning/intelligence, logistics, and finance/administration), the mutual-aid system, and the multi/interagency coordination required during a smallpox emergency. Management for incident command includes setting objectives and priorities, information (risk communications), safety, and liaison. Operations includes control and containment of a smallpox outbreak including ring vaccination, mass vaccination, adverse events monitoring and assessment, management of confirmed and suspected smallpox cases, contact tracing, active surveillance teams and enhanced hospital-based surveillance, and decontamination. Planning/intelligence functions include developing the incident action plan, epidemiological investigation and analysis of smallpox cases, and epidemiological assessment of the vaccination coverage status of populations at risk. Logistics functions include receiving, handling, inventorying, and distributing smallpox vaccine and vaccination clinic supplies; personnel; transportation; communications; and health care of personnel. Finally, finance/administration functions include monitoring costs related to the smallpox emergency, procurement, and administrative aspects that are not handled by other functional divisions of incident command systems. The plan was developed and is under frequent review by the LAC-DHS Smallpox Planning Working Group, and is reviewed periodically by the LAC Bioterrorism Advisory Committee, and draws upon the Smallpox Response Plan and Guidelines of the Centers for Disease Control and Prevention (CDC) and recommendations of the Advisory Committee on Immunization Practices (ACIP). The Smallpox Preparedness, Response, and Recovery Plan, with its SEMS framework and ICS structure, now is serving as a model for the development of LAC-DHS plans for responses to other terrorist or natural-outbreak responses.  相似文献   
998.
999.
Despite the worldwide distribution of Coxiella burnetii , Q fever is not a frequent infection in travelers. This disease should be considered in recent travelers from the tropics with unknown fever, headache, raised liver enzymes, and low platelets. Five cases in western travelers to the tropics returning with fever are presented.  相似文献   
1000.
Although most people who inject drugs (PWID) report receiving assistance during injection initiation events, little research has focused on risk factors among PWID for providing injection initiation assistance. We therefore sought to determine the influence of non-injection drug use among PWID on their risk to initiate others. We used generalized estimating equation (GEE) models on longitudinal data among a prospective cohort of PWID in Tijuana, Mexico (Proyecto El Cuete IV), while controlling for potential confounders. At baseline, 534 participants provided data on injection initiation assistance. Overall, 14% reported ever initiating others, with 4% reporting this behavior recently (i.e., in the past 6 months). In a multivariable GEE model, recent non-injection drug use was independently associated with providing injection initiation assistance (adjusted odds ratio [AOR] = 2.42, 95% confidence interval [CI] = 1.39–4.20). Further, in subanalyses examining specific drug types, recent non-injection use of cocaine (AOR = 9.31, 95% CI = 3.98–21.78), heroin (AOR = 4.00, 95% CI = 1.88–8.54), and methamphetamine (AOR = 2.03, 95% CI = 1.16–3.55) were all significantly associated with reporting providing injection initiation assistance. Our findings may have important implications for the development of interventional approaches to reduce injection initiation and related harms. Further research is needed to validate findings and inform future approaches to preventing entry into drug injecting.  相似文献   
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