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The impact of a professionally facilitated peer group intervention for HIV prevention among 400 low-income Chilean women was examined using a quasiexperimental design. At 3 months postintervention, the intervention group had higher HIV-related knowledge, more positive attitudes toward people living with HIV, fewer perceived condom use barriers, greater self- efficacy, higher HIV reduction behavioral intentions, more communication with partners about safer sex, and decreased depression symptoms. They did not, however, have increased condom use or self-esteem. More attention to gender barriers is needed. This intervention offers a model for reducing HIV for women in Chile and other Latin American countries.  相似文献   
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Hepatitis delta virus is a defective virus that can replicate only in the presence of hepatitis B virus. To determine the prevalence, circumstances of transmission, and clinical importance of infection with hepatitis delta virus, we obtained data on 262 patients with post-transfusion hepatitis who were positive for the hepatitis B surface antigen (HBsAg) even though they had received blood screened for it. We also studied 94 HBsAg carriers who were receiving repeated blood transfusions for other diseases, and 103 HBsAg carriers with hemophilia who were receiving various forms of coagulation factors. Antibody to hepatitis delta virus was found in 9 of 262 patients (3.5 per cent) with post-transfusion hepatitis, 5 of 234 (2 per cent) with self-limited disease, and 4 of 28 (14.5 per cent) with fulminant disease (P less than 0.05). The absence of IgM antibodies to the hepatitis B core antigen indicated that three of the nine patients with both HBsAg and antibodies to hepatitis delta virus had been carriers of HBsAg at the time of transfusion, and the acute disease represented the combined effects of the two viruses. Antibody to hepatitis delta virus was found in 3 of 94 Italian carriers of HBsAg who were receiving repeated blood transfusions, in none of 24 Brazilian, East German, or Australian hemophiliac carriers infused with clotting factors prepared from single or mini-pool volunteer plasma, and in 27 to 100 per cent of 79 hemophiliac carriers from European and U.S. series who received coagulation factors manufactured from large pools of plasma. We conclude that infection with hepatitis delta virus is likely to be more severe than infection with hepatitis B virus alone and that screening for HBsAg provides a high degree of safety in preventing infection with hepatitis delta virus, but that the risk is considerably greater in patients who are already carriers of HBsAg. We recommend that HBsAg carriers be given only blood derivatives prepared from a single donor or mini-pool donors.  相似文献   
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BACKGROUND AND AIM: In preascitic cirrhosis increased sodium retention occurs in kidney distal tubule in spite of normal aldosterone plasma levels. No clearance technique can dissect the respective contribution to sodium retention exerted by Henle's loop, distal convoluted tubule and collecting duct, so we evaluated proximal and distal tubular sodium handling in preascites during two manoeuvres that temporarily increase aldosterone secretion. METHODS: Ten patients with compensated cirrhosis and nine controls were studied in recumbency, during standing and after dopamine receptor blockade with metoclopramide through: 4 h renal clearances of sodium, potassium, lithium and creatinine; plasma levels of active renin and aldosterone. RESULTS: Whilst comparable in recumbency, aldosterone levels significantly rose during standing and after metoclopramide in both groups. In patients, dopaminergic blockade caused a fall of distal sodium delivery (P < 0.01) but urinary sodium excretion was unchanged because the reabsorbed fraction of distal sodium delivery also fell (P < 0.03). Cirrhotic patients showed the same findings in the passage from recumbency to standing. CONCLUSIONS: In preascitic cirrhosis, the distal tubular segments of the nephron are able to cope with decreases in tubular flow by reducing reabsorption at an aldosterone-independent site (possibly the loop of Henle).  相似文献   
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Pig production has increased significantly in the Eastern and Southern Africa (ESA) region during the past decade, especially in rural, resource-poor, smallholder communities. Concurrent with the increase in smallholder pig keeping and pork consumption, there have been increasing reports of porcine cysticercosis in the ESA region. This article reviews the findings concerning the presence and impact of porcine cysticercosis in seven of the ESA countries. Most of the reported findings are based on surveys utilising lingual palpation and post-mortem examination, however, some also used serological assays. In Tanzania, community-based studies on porcine cysticercosis indicate a prevalence of 17.4% in the northern highlands district of Mbulu and a prevalence range of 5.1-16.9% in the southern highlands. In Kenya recent surveys in the southwestern part of the country where smallholder pig keeping is popular indicate that 10-14% of pigs are positive for cysticercosis by lingual examination. Uganda has the most pigs in Eastern Africa, most of which are kept under smallholder conditions. Preliminary surveys in 1998 and 1999 at slaughterhouses in Kampala indicated a prevalence of porcine cysticercosis between 0.12 and 1.2%, however, a rural survey in northern Uganda in 1999 indicated 34-45% of pigs slaughtered in selected villages were infected. Additionally, a new survey of 297 pigs slaughtered in Kampala in 2002 indicated that pigs from the central region of the country were negative for cysticercosis while 33.7% of the pigs coming from the rural Lira district in the north were positive. Interestingly 8 piglet foetuses removed from an infected slaughtered sow coming from Lira district were all found to harbour cysts of T. solium providing evidence of congenital transmission of porcine cysticercosis. In Mozambique, abattoir records indicate that porcine cysticercosis is present in all provinces of the country. A serological survey on pigs in rural Tete Province found 15% of pigs positive. In Zimbabwe, a retrospective study in official abattoirs around the country from 1994 to 2001 reported a mean prevalence of 0.34% which is in contrast to a post-mortem survey in 1999, which showed that the prevalence of porcine cysticercosis in rural west Zimbabwe where smallholder pig keeping is popular was 28.6%. In Zambia, abattoir records reported porcine cysticercosis in six of the nine provinces. Routine meat inspection of 1316 pigs at a slaughter slab in Lusaka showed that 20.6% of the pigs had cysticercosis whereas serological testing of 874 pigs at the same abattoir indicated that 56.6% were found to have circulating antigens of Taenia solium. Field surveys based on lingual palpation in Southern and Eastern Provinces of Zambia revealed prevalences of 8.2-28.4 and 5.2%, respectively. South Africa has the largest number of pigs in Southern Africa and cysticercosis has been recognised as a problem in the country for many decades. There is strong evidence supporting the high prevalence of neurocysticercosis infecting humans from resource-poor areas of the country where pigs are being raised under smallholder conditions. In spite of this community-based surveys on porcine cysticercosis have never been conducted in South Africa and the last slaughterhouse survey was conducted nearly 40 years ago. The prevalences of porcine cysticercosis found in these ESA countries rank among the highest in the world and the disease is emerging as an important constraint for the nutritional and economic well being of resource-poor smallholder farming communities. The current findings suggest the widespread presence of human tapeworm carriers and thus a high risk of human cysticercosis in both rural areas and urban centres in the ESA region. More research is required in the region to assess the extent and public health and economic impact of T. solium infection in order to determine whether and what prevention and control efforts are needed.  相似文献   
108.
Diarrhea is a major public health problem that affects the development of children. Anthropometric data were collected from 274 children with (N = 170) and without (N = 104) diarrhea. Stool specimens were analyzed by conventional culture, polymerase chain reaction for enteroaggregative Escherichia coli (EAEC), Shigella, Cryptosporidium, Entamoeba, and Giardia species, and by enzyme-linked immunosorbent assay for fecal lactoferrin levels. About 50% of the study population was mildly to severely malnourished. Fecal lactoferrin levels were higher in children with diarrhea (P = 0.019). Children who had EAEC infection, with or without diarrhea, had high mean lactoferrin levels regardless of nutritional status. The EAEC and Cryptosporidium were associated with diarrhea (P = 0.048 and 0.011, respectively), and malnourished children who had diarrhea were often co-infected with both Cryptosporidium and EAEC. In conclusion, the use of DNA-biomarkers revealed that EAEC and Cryptosporidium were common intestinal pathogens in Accra, and that elevated lactoferrin was associated with diarrhea in this group of children.  相似文献   
109.
BACKGROUND: Exhaled nitric oxide (NO) levels may be elevated in patients with liver cirrhosis and autoimmune diseases. Primary biliary cirrhosis (PBC) is often associated with keratoconjunctivitis sicca (Sjogren syndrome [SS]), an extrahepatic autoimmune manifestation. The aim of this study was to evaluate the source of increased exhaled NO (ie, alveolar vs airway) in patients with PBC, whether associated with SS or not, and to evaluate its impact on oxygenation abnormalities. DESIGN: Observational controlled study. SETTING: University hospital. METHODS: The fractional alveolar NO concentration (FANO) and airway flux of NO (QbrNO) were measured by the multiple flows technique in 34 patients with PBC, 12 with associated SS, and were compared to 20 control subjects and 12 patients with primary SS. RESULTS: FANO was significantly higher in patients with PBC, associated with SS (mean [+/- SEM], 8.9 +/- 0.8 parts per billion [ppb]) or not (mean, 7.7 +/- 0.7 ppb) compared to healthy control subjects (mean, 4.6 +/- 0.5 ppb; p < 0.001) and to patients with primary SS (mean, 4.3 +/- 0.5 ppb; p < 0.001). FANO was significantly higher in cirrhotic patients with increased alveolar-arterial oxygen pressure difference (P[A-a]O(2)) compared to patients with normal P(A-a)O(2) values (9.8 +/- 0.8 vs 7.3 +/- 0.7, respectively; p = 0.018). When compared with control subjects and with patients with PBC not associated with SS, QbrNO was significantly increased in patients with both primary SS and SS associated with PBC. CONCLUSIONS: Increased exhaled NO levels found in PBC are from both alveolar and airway sources in patients with associated SS, but only FANO is associated with oxygenation impairment.  相似文献   
110.
To determine whether long-term therapy with recombinant interferon-alpha can improve the course of chronic delta hepatitis, 61 Italian patients with this disease were randomly assigned to receive either interferon-alpha-2b three times a week (5 MU/m2 for 4 mo and then 3 MU/m2 for another 8 mo) or no treatment. At the end of the 12-mo study, all patients were followed-up for 12 additional months. Normalization or decrease of more than 50% from baseline of serum ALT levels occurred in 42% of treated patients the fourth month of therapy, 26% the twelfth month and 3% the twenty-fourth month vs. 7%, 7% and 0%, respectively, in the control group. However, relapses occurred in 7 of 8 (87.5%) responders 1 to 10 mo (mean = 3.5 mo) after cessation of therapy. Liver biopsies were carried out at baseline and during the twelfth month of treatment. Histological improvement, mostly caused by decrease of portal inflammation, was observed in 57% of treated and 36% of untreated patients. Measures of antiviral activity (serum hepatitis delta virus RNA and intrahepatic hepatitis delta antigen) showed similar levels in treated and control patients. In treated patients the percentage of patients who were negative for HDV RNA never exceeded that of baseline. Although interferon-alpha in the dosage given in this study had no antiviral effect on patients with chronic hepatitis D, it reduced hepatic inflammation as measured by ALT levels. Whether a longer duration or reinstitution of interferon-alpha therapy would achieve long-term control of ALT levels and prevent chronic liver damage is not known.  相似文献   
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