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排序方式: 共有1110条查询结果,搜索用时 593 毫秒
1.
BACKGROUND/AIMS: Spontaneous bacterial peritonitis (SBP) is an important complication in cirrhotic patients. The aim of the present study was to assess the incidence, predictive factors and prognosis for renal impairment (RI) after SBP in cirrhotic patients from southern Brazil. METHODS: Of the 1030 hospitalizations evaluated, 114 episodes of SBP were diagnosed in 94 patients (mean age 49 years; 76.59% men). SBP diagnosis was established when the ascitic fluid polymorphonuclear cell count was equal to or greater than 250 cells/mm3. Five cases were excluded. The variables assessed as possible predictors of steady or progressive RI were blood urea nitrogen and creatinine levels before the diagnosis of SBP; type of infection, antibiotic prophylaxis, first episode or recurrent SBP, presence of gastrointestinal bleeding and hepatic encephalopathy during hospitalization, SBP resolution, Child-Pugh classification, levels of blood pressure, ascitic fluid and blood polymorphonuclear cell count, bacteriological data (positive and negative ascitic fluid culture), albumin, bilirubin, sodium and prothrombin time at the moment of diagnosis. RESULTS: The incidence of SBP was 11.07%. In 61 (55.96%) episodes, SBP was associated with RI (transient in 57.37%; steady in 19.67%; and progressive in 22.95%). The mortality rate associated with progressive RI was 100%; 58.33% with steady RI; and 2.85% with transient RI. The mortality rate in patients with or without RI was 36.07% and 6.25%, respectively (P<0.001). The level of creatinine (greater than or equal to 1.3mg/dL) before the diagnosis of SBP and the rate of infection resolution were the only predictors of RI in the multivariate analysis. CONCLUSIONS: RI after SBP is a common complication, and indicates a poor prognosis for this infection. High levels of creatinine before infection and the rate of infection resolution are independent predictors of RI.  相似文献   
2.
BACKGROUND: Oral hairy leukoplakia (OHL) may be an indicator of the progression of Human Immunodeficiency Virus (HIV)-induced immuno-depression, and the evaluation of risk factors leading to OHL is important in the management of these HIV-infected patients. However, there are few studies that analyze risk factors leading to OHL in the Brazilian population. The aim of this case-control study is to present data about prevalence rates and risk factors leading to OHL in a sample of HIV-infected adults in Brazil. METHODS: This case-control study included 111 HIV-infected patients treated at a clinic for sexually transmitted diseases and HIV. In the initial examinations with dentists, variables were collected from all patients. Diagnosis of OHL was performed in accordance with the International Classification System and cytological features. The Fisher and the chi-squared tests were used for statistical analysis. The proportional prevalence and odds ratio were estimated. RESULTS: Outcome presented a positive, statistically significant association among the presence of OHL and viral load of 3000 copies/mul or greater (P = 0.0001; odds ratio (OR) = 5.8), presence of oral candidiasis (P = 0.0000; OR = 11.1), previous use of fluconazole (P = 0.0000; OR = 24.6), and use of systemic acyclovir (P = 0.032; OR = 4.3). Antiretroviral medication presented a negative, statistically significant association with the presence of OHL (P = 0.002; OR = 8.4). CONCLUSIONS: Prevalence of OHL was 28.8%. Viral load, oral candidiasis, previous use of fluconazole, and systemic acyclovir were determined to be risk factors for OHL. Antiretroviral medication proved to be protective against the development of OHL.  相似文献   
3.
Although previous studies have shown successful treatment of persistent diarrhea (PD) with the use of yogurt-based diets, some recent ones speculate the need of special formulas for the nutritional management of PD complicated cases. In the present study, we tested the hypothesis that the consumption of 3 lactose-free diets, with different degrees of complexity, is associated with lower stool output and shorter duration of diarrhea when compared with the use of a yogurt-based one on the nutritional management of PD. A total of 154 male infants, aged between 1 and 30 months, with PD and with or without dehydration, were randomly assigned to 1 of 4 treatment groups. Throughout the study, the patients were placed in a metabolic unit; their body weights and intakes of oral rehydration solution, water, and formula diets, in addition to outputs of stool, urine, and vomit, were measured and recorded at 24-hour intervals. Four different diets were used in this study: diet 1, yogurt-based formula; diet 2, soy-based formula; diet 3, hydrolyzed protein-based formula; and diet 4, amino acid–based formula. Throughout the study, only these formula diets were fed to the children. The data showed that children fed the yogurt-based diet (diet 1) or the amino acid–based diet (diet 4) had a significant reduction in stool output and in the duration of diarrhea. The use of an inexpensive and worldwide-available yogurt-based diet is recommended as the first choice for the nutritional management of mild to moderate PD. For the few complicated PD cases, when available, a more complex amino acid–based diet should be reserved for the nutritional management of these unresponsive and severe presentations. Soy-based or casein-based diets do not offer any specific advantage or benefits and do not seem to have a place in the management of PD.  相似文献   
4.
Rapid, accurate and inexpensive methods are essential to detect drug-resistant Mycobacterium tuberculosis and allow timely application of effective treatment and precautions to prevent transmission. The proportion method, the MTT and Alamar Blue redox methods, and the D29 mycobacteriophage assay, were compared for their ability to detect resistance to isoniazid and rifampicin. When tested against a panel of known M. tuberculosis strains, the redox methods and the D29 assay showed good sensitivity and specificity compared to the proportion method, suggesting that they could be useful alternatives for identifying multidrug resistance in M. tuberculosis.  相似文献   
5.
Hyperparathyroidism contributes significantly to decreased bone mineral density (BMD) in end-stage renal disease patients, but this negative influence is not homogeneous throughout the skeleton. We studied the BMD by dual-energy X-ray absorptiometry on total body and on different regions of the skeleton in 42 patients with severe hyperparathyroidism on hemodialysis. We also evaluated the relationship between different risk factors and BMD found on the regions examined in these patients. The legs and other sites where cortical bone predominate were mostly affected, whereas trabecular bone was relatively preserved. This is probably the result of the different effects of hyperparathyroidism on cortical and trabecular bone, but we cannot rule out the interference of ectopic calcifications and sclerotic lesions of vertebral end-plates falsely increasing lumbar spine BMD. The main determinants of low total-body BMD were, in order of importance, immobility, high intact parathyroid hormone levels, low body mass index, and low albumin. Eleven patients presented with pathologic fractures, mainly in the legs, and BMD was lower in this group than in patients without fractures. In conclusion, our study makes clear that hyperparathyroidism is a great threat to bone density in hemodialysis patients, mainly in the legs, the site mostly affected by fragility fractures in our patients. Physicians must worry not only with high parathyroid hormone levels, but also with the nutritional state of these patients.  相似文献   
6.
Acase of periodic sweating with multifocal dystonia is reported in a 60-year-old woman. At the age of 48 years, she presented with involuntary twisting of the lower face on the right. Six months later she noticed similar movements in the head and right arm. Four years later she began having attacks of generalized sweating over the whole face, anterior region of the trunk and both arms. The attacks occurred hourly each and every day. They lasted for about 10 min and were followed by voluntary urinary voiding. The biochemical and laboratory investigations showed no abnormalities except for the luteinizing hormone and follicle-stimulating hormone values that were below normal. The computerized tomography and magnetic resonance imaging scans revealed a suprasellar cyst. Clonazepam was introduced with partial improvement of the dystonic movements but not of the sweating attacks. The patient refused surgery. Acetazolamide was added and reduced the sweating attacks. We speculate that the periodic sweating may be related to cerebrospinal fluid production and cyst enlargement, hence the ability of acetazoleamide, which reduces cerebrospinal fluid production, to reduce attacks.  相似文献   
7.
OBJECTIVE: To evaluate the nutritional status and dietary habits of children of the Alto Xingu, Central Brazil, according to age. SUBJECTS: 172 Indian children (<10 years of age) of Alto Xingu tribes. METHODS: Date of birth, sex, weight, height (NCHS reference) and questionnaire of dietary habits at the time of field work. RESULTS: Of the 103 children less than 5 years of age, 34% presented protein-energy malnutrition (PEM), according to Gomez's criteria, of which only 2% with grade II malnutrition and no child presented severe PEM. In relation to the Z scores for the 172 children studied, it was observed that those younger than 1 year (n=25) presented weight for age (median, M=+0.43) and weight for height (M=+1.33) greater (p<0.05) than the children with ages between 12 and 60 months (n=78) (weight for age, M=-0.54; weight for height, M=+0.29) and between 60 and 120 months (n=69) (weight for age, M=-0.78; weight for height, M=+0.27). The height for age Z scores for the population studied showed a shift to the left in relation to the reference population in the three age groups (<12 months, M=-0.95; 12 to 60 months, M=-1.22 and 60 to 120 months, M=-1.40). The mothers nursed, without exception, to the age of 24 months, and the frequency of breastfeeding decreased progressively to age 42 months. The introduction of solid foods started at the age of 6 months and after the 10th month all the children ate "beiju" (flat bread), fruit and fish. CONCLUSION: The nutritional status of Alto Xingu Indian children, in 1992, is adequate and similar to that previously observed between 1974 and 1980.  相似文献   
8.
OBJECTIVE: Anatomic patency after percutaneous transluminal angioplasty (PTA) of the superficial femoral and popliteal arteries does not guarantee clinical success. The aim of this report is to determine the causes of clinical failure after PTA. METHODS: The records of all patients who have undergone PTA of the femoropopliteal arterial segment by our vascular group were retrospectively reviewed. Only patients with complete records and at least one postprocedure clinical and anatomic assessment within the same 30-day time interval were included. Success was defined according to the Society for Vascular Surgery/International Society for Cardiovascular Surgery Ad Hoc Subcommittee on Reporting Standards for Endovascular Procedures. Anatomic cumulative patency and clinical success were calculated according to life table analysis on an intent-to-treat basis. RESULTS: We identified 85 patients who met inclusion criteria. We treated 112 lesions with an average stenosis of 80% +/- 16% and lesion length of 2.3 +/- 1.8 cm. Technical failure occurred in six (5.4%) of 112 lesions. Cumulative clinical success was 69% at 1 year, 54% at 2 years, 49% at 3 years, and 40% at 4 years. Anatomic patency was 74% at 1 year, 62% at 2 years, 57% at 3 years, and 52% at 4 years. There were 45 clinical failures; of these, twenty-seven (60%) occurred in conjunction with anatomic failure. Anatomic failure was due to restenosis in 12 patients (44%), occlusion in eight patients (30%), and restenosis with progression of disease in six patients (22%). Anatomic failure at the time of the procedure occurred in one patient (4%). Clinical failure occurred despite anatomic patency in the remaining 18 patients (40%). Etiology for clinical failure in this latter group included progression of disease within the treated vessel in 12 patients (67%), iliac disease in three patients (17%), tibial disease in two patients (11%), and bypass graft failure in one patient (5%). Fifty percent of all 45 clinical failures were successfully treated with supplemental percutaneous procedures. CONCLUSION: A PTA is an acceptable therapeutic option for the treatment of focal occlusive disease of the femoropopliteal arterial segment. Most clinical failures were due to anatomic failure, but a significant number occurred despite patency at the PTA site. Although primary clinical success rates were inferior to surgical bypass graft, supplemental PTA was possible in 50% of patients. Repeat percutaneous treatment may extend the interval of clinical success and may obviate the need for surgical bypass graft.  相似文献   
9.
We describe herein the structural optimization of new piperamide analogues, designed from two natural prototypes, piperine 1 and piperdardine 2, obtained from Piper tuberculatum Jacq. (Piperaceae). Molecular modeling studies using semiempirical AM1 method were made in order to establish rational modifications to optimize them by molecular simplification. The targeted compounds (10) and (11) were respectively obtained using benzaldehyde (12) and para-anisaldehyde (13) as starting materials. 1H NMR spectra showed that the target compounds were diastereoselectively obtained as the (E)-isomer, the same geometry of the natural prototypes. These new synthetic amides presented significant hypotensive effects in cardiovascular essays using in vivo methodologies. Compound 11 (N-[5-(4′-methoxyphenyl)-2(E)-pentenoyl]thiomorpholine) showed a potency 10,000 times greater than its prototype 5, evidencing an optimization of the molecular architecture for this class of hypotensive drug candidates.  相似文献   
10.
Parkinson''s disease is the second most frequent neurodegenerative disorder in the world, affecting 1-2% of individuals over the age of 65. The etiology of Parkinson''s disease is complex, with the involvement of gene-environment interactions. Although it is considered a disease of late manifestation, early-onset forms of parkinsonism contribute to 5–10% of all cases. In the present study, we screened mutations in coding regions of PARK2 and PINK1 genes in 136 unrelated Brazilian patients with early-onset Parkinson''s disease through automatic sequencing. We identified six missense variants in PARK2 gene: one known pathogenic mutation, two variants of uncertain role, and three nonpathogenic changes. No pathogenic mutation was identified in PINK1 gene, only benign polymorphisms. All putative pathogenic variants found in this study were in heterozygous state. Our data show that PARK2 point mutations are more common in Brazilian early-onset Parkinson''s disease patients (2.9%) than PINK1 missense variants (0%), corroborating other studies worldwide.  相似文献   
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