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991.
We examined the association of breastfeeding and the presence of chronic respiratory symptoms among 5182 Brazilian schoolchildren 7-14 years of age who were participants in the International Study on Asthma and Allergies in Childhood (ISAAC). The prevalence of medically diagnosed asthma and current wheeze were respectively 4.6% (95% confidence interval [CI] 4.0%-5.2%) and 11.9% (95% CI 11.0%-12.8%). Ninety percent of the mothers in our study population had breastfed their child. After adjusting for potential confounding factors, we found that children who had not been breastfed were more likely to have a medical diagnosis of asthma (odds ration [OR] = 1.51, 95% CI 1.00-2.51), experience current wheeze (OR = 1.29, 95% CI 0.96-1.74), and wheeze after exercise (OR = 1.51, 95% CI 1.01-2.27) than children who had been breastfed for more than 6 months. This effect was only present among children with no family history of asthma (OR = 1.54, 95% CI 0.90-2.42 for medical diagnosis of asthma; OR = 1.27, 95% CI 0.93-1.75 for current wheezing; and OR = 1.74, 95% CI 1.12-2.6 for wheeze after exercise). We conclude that the low prevalence of asthma and wheeze observed in our population may be partly related to the high level of breastfeeding.  相似文献   
992.
BACKGROUND: The histopathological spectrum and role of hepatitis viruses in cases of hypertransaminasaemia of unknown aetiology have not been correctly analysed in a sufficiently large number of patients. METHODS: We studied 1075 consecutive patients referred for liver biopsy because of elevation of alanine aminotransferase (ALT) levels for more than six months. From this population we selected those cases in whom the aetiology could not be defined from clinical, biochemical, and serological data obtained before biopsy. In these patients liver biopsies were reviewed, and hepatitis B virus (HBV)-DNA and hepatitis C virus (HCV)-RNA were assayed in serum by polymerase chain reaction (PCR). Serum hepatitis G virus (HGV)-RNA was determined by PCR in 74 patients. RESULTS: Of 1075 patients studied, the cause of the increased serum ALT levels remained elusive after appropriate testing in 109 patients (10.1%). Liver biopsies from these patients showed non-specific changes in 32.7% of cases, non-alcoholic steatohepatitis (NASH) in 15.8%, and chronic hepatitis or cirrhosis in 51.5%. HBV-DNA and/or HCV-RNA was detected more frequently in cryptogenic liver disease than in healthy blood donors (26.7% v 3.4%; p<0.001). HGV-RNA was found in only one patient. The proportion of cases with detectable HBV-DNA or HCV-RNA was 14.3% in patients with non-specific changes or NASH, 30.7% in patients with chronic hepatitis, and 61.5% in patients with cirrhosis. Cirrhosis was found more frequently in patients with positive HBV-DNA and/or HCV-RNA in serum than in those who tested negatively (p=0.005). CONCLUSIONS: In our series, patients in whom biochemical and serological data did not determine the aetiology of the disease represented 10% of all cases referred for liver biopsy for persistent elevation of serum transaminases. Approximately 50% of patients had chronic hepatitis or cirrhosis and the remainder had NASH or non-specific changes. Occult viral infections were found in a high proportion of cases in the first group and in a low percentage of patients in the second.  相似文献   
993.
Noninvasive and invasive diagnostic techniques have been shown to achieve comparable performances in the evaluation of suspected ventilator-associated pneumonia (VAP). We studied the impact of both approaches on outcome in a prospective, open, and randomized study in three intensive care units (ICUs) of a 1,000-bed tertiary care university hospital. Patients with suspected VAP were randomly assigned to noninvasive (Group 1) versus invasive (Group 2) investigation (tracheobronchial aspirates [TBAS] versus bronchoscopically retrieved protected specimen brush [PSB] and bronchoalveolar lavage [BAL]. Samples were cultured quantitatively, and BAL fluid (BALF) was examined for intracellular organisms (ICO) additionally. Initial empiric antimicrobial treatment was administered following the guidelines of the American Thoracic Society (ATS) and adjusted according to culture results (and ICO counts in Group 2). Outcome variables included length of ICU stay and mechanical ventilation as well as mortality. Overall, 76 patients (39 noninvasive, 37 invasive) were investigated. VAP was microbiologically confirmed in 23 of 39 (59%) and 23 of 37 (62%) (p = 0.78). There were no differences with regard to the frequencies of community-acquired and potentially drug-resistant microorganisms (PDRM). Antimicrobial treatment was changed in seven patients (18%) of Group 1 and 10 patients (27%) of Group 2 because of etiologic findings (including five of 17 with ICO = 2% (p = not significant [NS]). Length of ICU stay and mechanical ventilation were also not significantly different in both groups. Crude 30-d mortality was 31 of 76 (41%), and 18 of 39 (46%) in Group 1 and 14 of 37 (38%) in Group 2 (p = 0.46). Adjusted mortality was 16% versus 11% (p = 0.53), and mortality of microbiologically confirmed pneumonia 10 of 23 (44%) in both groups (p = 1.0). We conclude that the outcome of VAP was not influenced by the techniques used for microbial investigation.  相似文献   
994.
Nowadays, it is estimated that 85% of the infants born with congenital heart disease (CHD) will survive to adulthood, thanks mainly to surgical or therapeutic procedures performed during infancy or childhood. The clinical profile and disease pattern of adults with CHD is changing. The prevalence of certain adult CHDs, such as tetralogy of Fallot, transposition of the great arteries or univentricular heart, is rising, but these conditions have practically become new diseases as a result of therapy. Most surviving patients present residua, sequelae, or complications, which can progress during adult life. These disorders can present electrophysiological disturbances, valvular disease, persistent shunts, myocardial dysfunction, pulmonary or systemic vascular disease, problems caused by prosthetic materials, infectious complications, thromboembolic events, or extravascular disorders involving multiple organs or systems. In tetralogy of Fallot, the most striking problems that affect long-term prognosis are pulmonary valve regurgitation, right ventricle dysfunction, and atrial or ventricular arrhythmias. The main problems appearing after physiological atrial repair of transposition of the great arteries are related to right ventricular function, since it is structurally unprepared for systemic circulation, and atrial arrhythmias. Surgical repair of univentricular heart using Fontan techniques should be considered a palliative procedure that does not modify the underlying structural disorder and exposes the postoperative patient to severe complications and problems. The increase in the number of patients with CHD who will reach adulthood in the coming decades makes it necessary to carefully consider the new healthcare demands that are being generated, who should be responsible for them, and how and where solutions can be found.  相似文献   
995.
BACKGROUND: The purpose of this study was to assess the relationship between bone mineral density and insertion/deletion (I/D) angiotensin converting enzyme polymorphism (ACE) in hypertensive postmenopausal women. METHODS: Blood and urine samples from the study subjects were analyzed for calcium metabolism related parameters. Densitometry studies were conducted in the lumbar spine (L2 to L4). The ACE polymorphism was analyzed by polymerase chain reaction. RESULTS: Women with II genotype showed a higher intact parathyroid hormone (76 +/- 33 v 55 +/- 27 pg/mL and 52 +/- 26 pg/mL, P =.034) without a decrease in calciuria, and higher bone mineral density than women with ID and homozygotus deletion genotype (1.138 +/- 0.08 v 1.051 +/- 0.16 pg/mL and 1.053 +/- 0.16 pg/mL). CONCLUSIONS: The ACE polymorphism could be one of the factors causing bone mass variations.  相似文献   
996.
Mantle cell lymphoma (MCL) has an aggressive clinical course with a median survival < 3 years and is incurable with conventional chemotherapy. A large multicentre study with adequate follow-up may clarify the role of significant factors affecting outcome in autologous stem cell transplantation for MCL. Patients receiving an autologous transplant for MCL between 1988 and 1998, and reported to the European Blood and bone Marrow Transplant (EBMT) registry or Autologous Blood and Marrow Transplant Registry (ABMTR), were included. Expert haematopathology review was required on all identified patients. Disease and transplant details were requested from the transplant centres, and the final cohort of patients with verified pathology, adequate clinical information and follow-up was analysed. One hundred and ninety-five patients were included in the analyses (149 EBMT, 46 ABMTR) with a median follow-up of 3.9 years. The 2 year and 5 year overall survival were 76% and 50%, and progression free survival was 55% and 33% respectively. Disease status at transplant was the most significant factor affecting survival: patients with chemosensitive disease but not in first complete remission (CR1) were 2.99 times (95% CI: 1.66-5.38, P < 0.001) more likely to die than patients transplanted in CR1. Autologous transplantation probably improves survival in patients with MCL especially if performed in first CR.  相似文献   
997.
HIV risk was assessed in association with a history of incarceration and having a sexual partner with a history of incarceration in a population sample of low-income young women residing in San Francisco. Of the 235 women surveyed, 23% reported prior incarceration and 42% reported having a sexual partner with a history of incarceration. Prevalence of sexually transmitted infections (STIs) (including HIV) was no higher among previously incarcerated women or those with a sexual partner with a history of incarceration. Women with a prior incarceration were significantly more likely to report injecting drugs, exchanging sex for money or drugs, and history of forced sex. Women reporting sexual partners with a history of incarceration were significantly more likely to report incarceration history, history of STIs, and history of forced sex. Interventions aimed at reducing substance abuse, STIs, commercial/survival sex, and the effects of sexual coercion need to be strengthened for women within and transitioning out of correctional facilities.  相似文献   
998.
Somatostatin (SRIF) inhibits GH release from rat somatotropes by reducing adenylate cyclase (AC) activity and the free cytosolic calcium concentration ([Ca(2+)](i)). In contrast, we have reported that SRIF can stimulate GH release in vitro from pig somatotropes. Specifically, 10(-7) and 10(-15) M SRIF stimulate GH release from a subpopulation of high density (HD) somatotropes isolated by Percoll gradient centrifugation, whereas in low density (LD) somatotropes only 10(-15) M SRIF induces such an effect. To ascertain the signaling pathways underlying this phenomenon, we assessed SRIF effects on second messengers in cultured LD and HD cells by measuring cAMP, IP turnover, and [Ca(2+)](i). Likewise, contribution of the corresponding signaling pathways to SRIF-induced GH release was evaluated by blocking AC, PLC, extracellular Ca(2+) influx, or intracellular Ca(2+) mobilization. Both 10(-7) and 10(-15) M SRIF increased cAMP, IP turnover, and [Ca(2+)](i) in HD cells. Conversely, in LD cells 10(-7) M SRIF reduced [Ca(2+)](i), but did not alter cAMP or IP, and 10(-15) M SRIF was without effect. Interestingly, SRIF-stimulated GH release was abolished in both subpopulations by AC blockade, but not by PLC inhibition. Furthermore, SRIF-induced GH release was not reduced by blockade of extracellular Ca(2+) influx through voltage-sensitive channels or by depletion of thapsigargin-sensitive intracellular Ca(2+) stores. Therefore, SRIF stimulates GH secretion from cultured porcine somatotrope subpopulations through an AC/cAMP pathway-dependent mechanism that is seemingly independent of net increases in IP turnover or [Ca(2+)](i). These novel actions challenge classic views of SRIF as a mere inhibitor for somatotropes and suggest that it may exert a more complex, dual function in the control of porcine GH release, wherein molecular heterogeneity of somatotropes would play a critical role.  相似文献   
999.
Despite the information dealing with the differential phenotype and function of the main mouse dendritic cell (DC) subpopulations, namely, CD8alpha(-) and CD8alpha(+) DCs, their origin and involvement in antiviral immune responses in vivo are still largely unknown. To address these issues, this study used the changes occurring in DC subpopulations during the experimental infection by the Swiss (SW) strain of the mouse mammary tumor virus (MMTV). MMTV(SW) induced an 18-fold increase in lymph node DCs, which can be blocked by anti-CD62L treatment, concomitant with the presence of high numbers of DCs in the outer cortex, in close association with high endothelial venules. These data suggest that the DC increase caused by MMTV(SW) infection results from the recruitment of blood-borne DCs via high endothelial venules, by a CD62L-dependent mechanism. In addition, skin sensitization assays indicate that MMTV(SW) infection inhibits epidermal Langerhans cell migration to the draining lymph node. Moreover, data on the kinetics of MMTV(SW)-induced expansion of the different DC subsets support the hypothesis that CD8(-) and CD8(+) DCs represent different maturation stages of the same DC population, rather than myeloid- and lymphoid-derived DCs, respectively, as previously proposed. Finally, the fact that DCs were infected by MMTV(SW) suggests their participation in the early phases of infection.  相似文献   
1000.
Knee locking due to a single gouty tophus   总被引:2,自引:0,他引:2  
Knee locking is a highly incapacitating condition attributable to mechanical or functional factors. Pain, mostly of capsuloligamentous or intraosseous origin, is the cause of functional locking. Meniscal injuries are the most frequent arthroscopic finding in the locked knee, due to mechanical factors. We describe a patient experiencing locking during extension whose history and examination suggested a tear of the anterior horn of the lateral meniscus of the right knee; a diagnostic/therapeutic arthroscopy revealed an intraarticular gouty tophus growing from the anterior horn of the lateral meniscus.  相似文献   
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