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41.
In this study, our objective was to evaluate Etest strips containing exponential gradients of isoniazid (INH), rifampin (RIF), and streptomycin (STR) for susceptibility testing of Mycobacterium tuberculosis. M. tuberculosis isolates were tested for antimicrobial susceptibilities by the standard proportion method using L?wenstein-Jensen (LJ) medium and by the Etest. The MICs determined by the Etest were obtained at 5, 7, or 10 days. In some strains with Etest-discrepant results, radiometric susceptibility testing (BACTEC) was performed to determine a consensus result. M. tuberculosis concordance between the two methods was 97% (86 of 89 isolates) for RIF, 96% for INH (84 of 87 isolates), and 80% (61 of 76 isolates) for STR. Most of the MICs determined by the Etest were easy to interpret and readable within 5 days. Results correlated well with those obtained by the LJ proportion and BACTEC methods for INH and RIF. However, a high proportion of false-sensitive and false-resistant results were observed, most often for STR. We also observed that variations in the inoculum size of M. tuberculosis isolates affected the MICs to a substantial degree. These discrepancies, along with the expense of the media, the Etest strips, and the specialized equipment required (CO2 incubator), make this method less useful in developing countries.  相似文献   
42.
Aims : To evaluate the clinicopathological profile of 14 cases of nasal and paranasal sinusal adenocarcinoma, and to assess the usefulness of immunohistochemistry in the differential diagnosis of primary and metastatic intestinal-type adenocarcinoma.
Methods and results : Fourteen cases of nasal and paranasal adenocarcinoma, treated at IPOFG, Lisbon, between 1976 and 2002, were studied. Clinical records were reviewed and expression of cytokeratin (CK)7 and CK20 and of neuroendocrine markers was evaluated. The male : female ratio was 3 : 1, and the mean age of the patients was 65.3 years. Ten cases occurred in the paranasal sinuses. There was a history of professional exposure to dust in three patients. Twelve cases were high-grade intestinal type adenocarcinomas (ITAC) and two were low-grade. CK7 was present in 2/9 ITAC cases and CK20 in 8/9 ITAC and in cases of mixed and mucinous histology. All high-grade cases showed neuroendocrine differentiation. Seven of the 12 patients with high-grade adenocarcinoma died of the disease, with a mean follow-up of 47.4 months.
Conclusions : Nasal and paranasal adenocarcinoma mostly occurs in men in the 7th decade. ITAC is the most frequent histological type. The pattern of CK7/CK20 was not useful in the distinction between primary and metastatic intestinal adenocarcinoma. However, in the former, neuroendocrine differentiation proved to be a valuable tool in that distinction.  相似文献   
43.
Immunization with recombinant vaccinia viruses that specified the synthesis of Japanese encephalitis virus (JEV) glycoproteins protected mice from a lethal intraperitoneal challenge with JEV. Recombinants which coexpressed the genes for the structural glycoproteins, prM and E, elicited high levels of neutralizing (NEUT) and hemagglutination inhibiting (HAI) antibodies in mice and protected mice from a lethal challenge by JEV. Recombinants expressing only the gene for the nonstructural glycoprotein, NS1, induced antibodies to NS1 but provided low levels of protection from a similar challenge dose of JEV. Antibodies to the NS3 protein in postchallenge sera, representing the degree of infection with challenge virus, were inversely correlated to NEUT and HAI titers and levels of protection. These results indicate that although vaccinia recombinants expressing NS1 can provide some protection from lethal JEV infection, recombinants expressing prM and E elicited higher levels of protective immunity.  相似文献   
44.
45.
OBJECTIVE: Decreases in circulating growth hormone (GH) and its main biological messenger insulin-like growth factor-I (IGF-I) have been interpreted as part of the aging process. Because estrogens participate in modulating GH synthesis and secretion, hypoestrogenism in menopausal women may lead to GH deficiency. The aim of the present study was to determine the effect of hormone replacement therapy (HRT) on both GH and IGF-I levels as well as insulin concentrations in 50 menopausal women. DESIGN: Patients were assigned randomly into two treatment groups of 25 each; one group received three cycles of conjugated equine estrogen (CEE) 0.625 mg/day for 21 days, and the other, 1.25 mg/day during 21 days. Each also received chlormadinone acetate for 5 days. There was a control group consisting of regularly menstruating women. RESULTS: In the menopausal women, HRT increased significantly (p < 0.001) the low levels of GH and IGF-I; on the contrary the baseline insulin levels declined (p < 0.001) with HRT. A significant linear correlation (r = 0.90) was found between GH and IGF-I as well as with estradiol levels (r = 0.74) in the group of menopausal women receiving CEE 0.625 mg/day. This group of patients had a significant correlation (r = -0.63) between insulin and estradiol levels. No correlation was observed in the group receiving CEE 1.25 mg/day. CONCLUSIONS: HRT restored GH, IGF-I, and insulin levels to normal values in all women. Further research needs to be done to establish the beneficial effect of HRT regarding the prevention of the metabolic effects presumably caused by derangement in the somatotropic axis associated with aging.  相似文献   
46.
BackgroundIntrahepatic lithiasis (IHL) is a rare disease in the western world. Complications associated with IHL include acute cholangitis, liver atrophy, secondary biliary cirrhosis, and risk for intrahepatic cholangiocarcinoma. Liver resection is considered the treatment of choice for IHL. The objective of this study was to analyze patients who underwent liver resection for non-Asian hepatolithiasis.Methods127 patients with symptomatic non-Asian hepatolithiasis underwent resection in six institutions. Demographic data, clinical presentation, diagnosis, classification according to stone location, presence of atrophy, bile duct stricture, biliary cirrhosis, incidence of cholangiocarcinoma, treatment and postoperative course were evaluated.Results52 patients (40.9%) were male and the mean age was 46.1 years. Sixty-six patients (51.9%) presented with history of cholangitis. Stones were located in the left lobe in 63 (49.6%), and right lobe in 28 patients (22.0%). Atrophy was observed in 31 patients (24.4%) and biliary stenosis in 18 patients (14.1%). The most common procedure performed was left lateral sectionectomy in 63 (49.6%) patients, followed by left hepatectomy in 36 (28.3%), right hepatectomy in 19 (15.0%), and associated hepaticojejunostomy in 28 (22.0%). Forty-two patients (33.0%) presented postoperative complications and the most common were biliary fistula (13.3%) and surgical site infection (7.0%). Postoperative mortality was 0.7%. Intrahepatic cholangiocarcinoma was observed in 2 patients (1.5%). Recurrence was identified in 10 patients (7.8%), mostly with bilateral stones and/or hepaticojejunostomy.ConclusionLiver resection is the standard treatment for symptomatic unilateral or complicated IHL with good operative results. Risk of cholangiocarcinoma was low in non-Asian patients.  相似文献   
47.
To determine whether or not the frequency of migraine attacks increased at weekends in employed patients and if so, whether or not this was related to the type of migraine, 35 female patients prospectively recorded the presence or absence of migraine attacks daily over a six-week period. They were also asked to estimate the frequency with which emotional factors predisposed to their migraine attacks and to provide details of their occupation. A diagnosis of common (migraine without aura) or classical migraine (migraine with aura) was made according to both the criteria of the Ad Hoc Committee on the Classification of Headache and those of the International Headache Society. Eleven percent and 6% of patients, respectively, felt that emotional factors "usually" or "always" predisposed to migraine attacks. There was no significant increase in the frequency of migraine attacks at weekends in either the total group or in the employed patients. Similarly, the type of migraine made no difference to the results. There was therefore no evidence for a delayed onset of migraine at weekends related to the weekday stress of employment.  相似文献   
48.
In order to investigate the health conditions of current employees in a government-owned bank in the State of Rio de Janeiro, we performed a cross-sectional study in two departments where systematic sampling was applied. Among the health conditions, we focused on the employees' eating habit profile using a questionnaire on frequency of food group consumption analyzed through a summary measure (eating score). Although the majority of the study population display good eating habits, the results confirmed a major difference between genders. Some 60% of men had scores higher than the population mean (51.2), as compared to only 45% of women. In addition, we observed that men, and particularly younger men, consumed more foodstuffs that were rich in saturated fat, salt, and sugar as compared to women. The findings indicate that quality of one's diet along with changes in other habits and behaviors (like smoking and sedentary life style) should be part of programs to promote health in the workplace, with a view towards controlling cardiovascular and other diseases.  相似文献   
49.
Extracellular deposits of fibrillar beta-amyloid are a characteristic neuropathology of Alzheimer's disease (AD). We have developed a novel antibody to a hypothesized "older isomer" of the amyloid protein. This antibody, raised against a synthetic beta-amyloid peptide containing isoaspartic acid at position 7 (isoaspartic-7-Abeta), reacts with isoaspartic-7-Abeta, a nonenzymatic modification found in long-lived proteins. Plaques stained with this antibody are thioflavine positive and are found throughout the frontal and entorhinal cortices of AD cases. In frontal cortex, isoaspartic-7-Abeta plaques are clustered but have a widespread distribution in all cortical layers. Isoaspartic-7-Abeta is found primarily in the core of individual plaques surrounded by nonisomerized amyloid. Activated microglia are associated with plaques containing isomerized and nonisomerized amyloid. In contrast to AD, isoaspartic-7-Abeta plaques in Down's syndrome (DS) cases are found primarily in the superficial layers of frontal cortex. Using image analysis isoaspartic-7-Abeta deposition was correlated with dementia severity in AD and with age in DS. The results indicate that this antibody against altered aspartyl amyloid could be a useful indicator of the age of amyloid plaques.  相似文献   
50.
Interleukin 6 (IL-6) levels have been shown to be increased in a number of autoimmune disorders and have recently been shown to be elevated in the serum of schizophrenic patients. Given the involvement of the CNS in schizophrenia, levels of interleukin-6 in the CSF are also of interest. Thus, we examined levels of both CSF and serum IL-6 concomitantly to determine if these levels were different from control values. In addition, we examined these measures in patients both on and off antipsychotic drugs to determine if any medication or exacerbation effects may account for the difference from controls. CSF IL-6 was measured by ELISA in 61 drug-free male schizophrenic (DSM-IIIR) patients and 25 well-screened healthy male control subjects. Serum IL-6 was measured in 43 of the 61 patients, and in 16 control subjects. Serum IL-6 was significantly higher in the schizophrenic patients compared to control subjects. CSF IL-6 was also higher in the patients, but the difference was not statistically significant. Paired data showed no medication or exacerbation effects on CSF IL-6, but plasma IL-6 significantly decreased in patients that experienced an exacerbation after medication withdrawal. The results indicate that IL-6 levels may be altered in schizophrenia. The relative decrease in exacerbated patients following haloperidol withdrawal may be indicative of a compensatory response of plasma IL-6 levels to relapse.  相似文献   
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