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991.
We investigated the effect of alcohol (3 g/kg body weight intragastrically) on lead-induced (50 mg/kg body weight intragastrically) oxidative stress in adult rat brain. Ethanol was found to potentiate the accumulation of lead in the rat brain by 100%. Lead and ethanol in combination also enhanced lipid peroxidation, a deteriorative process of biomembranes, and markedly decreased the antioxidant capacity of neuronal cells in terms of reduced activities of antioxidant enzymes i.e., superoxide dismutase, catalase and glutathione peroxidase. Further, the activity of glutathione reductase was also significantly decreased in lead and ethanol co-exposed animals as compared to only lead-treated animals, which had altered glutathione status. The results of the present study show that ethanol makes the adult rat brain more susceptible to the neurotoxic effects of lead by accentuating the oxidative stress induced by lead.  相似文献   
992.
The study analyses 111 patients of brain stem glioma; seen in neurosurgery Dept., AIIMS, N. Delhi, India, from Jan '83 to March '97; 60% of the patients were under the age of 15 years, with two peaks in age distribution, 6-10 years & 36-45 years & there was slight male preponderance in all age groups. Most common site of tumour was pons both in adults & children. Pyramidal & cerebellar signs were more frequently seen in children. Duration of symptoms was usually less than six months (in 65.5% of cases). Surgical management was attempted in 72 patients with post of radiotherapy & chemotherapy, rest of the 39 cases were treated with radiotherapy, chemotherapy & antitubercular treatment (if indicated). Improvement was seen in 30% patients postoperatively. Outcome was better in patients who were treated surgically. Astrocytoma was most common histological diagnosis (62%) & glioblastoma was not uncommon & was seen in 10 (13.8%) cases.] We conclude that the patients with brainstem glioma can be helped by surgical decompression, followed by adjuvant radiotherapy & chemotherapy.  相似文献   
993.
An algorithm for diagnosis of pulmonary fibrosis in the tropical countries has been developed on the basis of the common causes of fibrosis, and the availability and feasibility of different diagnostic techniques in those countries. First, it is important to exclude common diseases such as the atypical or occult forms of bronchiectasis, pulmonary tuberculosis, and chronic bronchitis, which often overshadow interstitial pulmonary fibrosis. A good history and physical examination supplemented with chest radiography and simple lung function tests are generally enough to narrow down the list of causes of diffuse lung disease to interstitial pulmonary fibrosis. The real difficulty lies in identifying the idiopathic or "lone" forms from the secondary forms of pulmonary fibrosis. High-resolution CT is helpful in a large number of patients. Transbronchial lung biopsy is performed in a select population of patients. Open surgical or thoracoscopy guided biopsy is the gold standard, but is rarely required.  相似文献   
994.
995.
Diagnosis of venous disorders using impedance plethysmography   总被引:2,自引:0,他引:2  
Impedance plethysmography (IPG) was carried out in one hundred and forty-one patients suspected of venous disorders using Parulkar's method. In these patients occlusive impedance phlebography (OIP) and venography were also carried out using standard procedures. Comparison of IPG and OIP observations with venographic findings revealed sensitivity of these methods to be 65% and 77.7% in the diagnosis of primary varicosity of veins and chronic deep vein thrombosis respectively with a specificity of 85%. Occlusive impedance phlebograms showing unilateral decrease in OIP parameters were observed to be sufficiently diagnostic. IPG observations in 5 patients with arterio-venous malformation were observed to be different from those in patients with deep vein thrombosis.  相似文献   
996.
Endometrial stromal sarcomas are low-grade malignant tumors that may pose a diagnostic challenge, especially when they are present in an extrauterine site. Owing to the presence of an arborizing vasculature and cells with an undifferentiated appearance, endometrial stromal sarcomas can be confused with several soft-tissue neoplasms. We studied 17 endometrial stromal sarcomas, eight hemangiopericytomas, 14 solitary fibrous tumors, and 16 synovial sarcomas immunohistochemically, detecting the following antigens: CD10, estrogen receptor, progesterone receptor, bcl-2, CD34, smooth muscle antigen, epithelial membrane antigen and cytokeratin (AE1/AE3). Most endometrial stromal sarcomas stained positively for CD10 (16/17), estrogen receptor (17/17), progesterone receptor (15/17), and bcl-2 (17/17). Staining with antismooth muscle antigen was seen in 11 of 17 cases of endometrial stromal sarcoma, with more intense staining seen in areas showing smooth muscle differentiation. Staining with AE1/3 was seen in four of 17 endometrial stromal sarcomas, with two of the positive cases containing epithelioid cells. None of the endometrial stromal sarcomas expressed epithelial membrane antigen or CD34. More than half of the hemangiopericytomas (4/8) and solitary fibrous tumors (9/14) cases demonstrated CD10 expression either focally or in a patchy cytoplasmic and membranous pattern. Hemangiopericytomas, solitary fibrous tumors, and synovial sarcomas did not express estrogen receptor. Four of eight hemangiopericytomas and seven of 14 solitary fibrous tumors also showed patchy progesterone receptor expression. CD34 expression was identified in six of eight hemangiopericytomas and 13 of 14 solitary fibrous tumors, but we did not find expression of CD34 in synovial sarcoma. Differences between endometrial stromal sarcoma and other soft-tissue tumors were detected for all of the immunohistochemical markers (P<0.05), except anti-bcl-2 and AE1/3. Antibodies against CD10 mark a substantial number of hemangiopericytomas and solitary fibrous tumors (albeit not diffusely) and should always be combined with antiestrogen receptor and CD34 when the differential diagnosis includes endometrial stromal sarcoma. Unlike estrogen receptor antibodies, progesterone receptor antibodies show at least focal nuclear staining in most hemangiopericytomas, solitary fibrous tumors and rare synovial sarcomas, and are not useful for this differential diagnosis. All endometrial stromal sarcomas expressed bcl-2, mostly in a diffuse pattern, but this did not distinguish between endometrial stromal sarcoma and mimics. We therefore recommend the use of a small antibody panel comprising anti-CD10, anti-estrogen receptor, and anti-CD34 to distinguish endometrial stromal sarcomas from tumors with a predominant hemangiopericytomatous growth pattern.  相似文献   
997.
BACKGROUND: The choice of treatment can have a major impact on the total costs associated with asthma care. OBJECTIVE: To determine the relative cost-effectiveness of twice-daily treatment with inhaled fluticasone propionate-salmeterol via Diskus, 100/50 microg, with that of once-daily treatment with oral montelukast as initial maintenance therapy in patients with persistent asthma uncontrolled with a short-acting beta2-agonist alone. METHODS: Data from a randomized, double-blind, double-dummy, 12-week clinical trial were analyzed. Efficacy end points included (1) symptom-free days (SFDs) during the 12-week period and (2) a 12% or greater increase in forced expiratory volume in 1 second (FEV1) from baseline. The economic analysis was performed from a payer's perspective, and hence only direct costs were included in the analysis. The incremental cost-effectiveness ratio (ICER), which is the mean difference in average costs divided by the mean difference in average effectiveness, was calculated for both effectiveness outcomes (SFDs and FEV1). RESULTS: For the SFDs end point, the ICER for fluticasone propionate-salmeterol vs montelukast was $2.87 (95% confidence interval, -$1.08 to $6.65), indicating that it costs, on average, an extra $2.87 per day for an additional SFD with fluticasone propionate-salmeterol than with montelukast. With regard to FEV1, the ICER was $1.79 (95% confidence interval, -$0.72 to $3.86), indicating that it costs, on average, an extra $1.79 per day to achieve a lung function improvement of 12% or greater from baseline with fluticasone propionate-salmeterol than with montelukast. At a widely acceptable ceiling ratio of $9.95 per day, the probability of fluticasone propionate-salmeterol being more cost-effective than montelukast was 99.8% for SFDs and was almost 100% for an FEV1 improvement of 12% of greater. CONCLUSIONS: Treating 2 main components of asthma, inflammation and smooth muscle dysfunction, using fluticasone propionate-salmeterol is more cost-effective than using a single mediator antagonist alone, such as montelukast, as initial maintenance therapy for persistent asthma in patients treated with a short-acting beta2-agonist only.  相似文献   
998.
Enterococci are members of the natural microbiota of animal and human intestinal tracts and are capable of causing opportunistic infections. They are also used as starter cultures in the food industry as well as in health supplements and probiotics by the pharmaceutical industry. This Janus-faced status requires a careful evaluation on the basis of pathogenic traits to ensure the safety of the strain used to produce food and pharmaceuticals. We performed gapped-genome sequencing of a probiotic strain Enterococcus faecalis Symbioflor 1 and present initial results deriving from comparative genome analysis with that of the previously sequenced pathogenic clinical isolate E. faecalis V583. There was strong overall conservation of synteny between both strains and a detailed analysis revealed the absence of large genomic regions from the chromosome of the probiotic strain, indicating gene loss. Genes absent from the Symbioflor 1 strain included those encoding the enterococcal cytolysin, enterococcal surface protein, and gelatinase (coccolysin) as well as hyaluronidase and the peptide antibiotic AS-48. This data was confirmed using PCR primers specific for the respective genes. However, other enterococcal determinants such as aggregation substance, collagen adhesion protein, the ability to resist oxygen anions as well as capsule formation were detected. The presence of these traits may be advantageous for the strain Symbioflor 1 since they potentially enable colonization and proliferation of the bacterium on mucosal surfaces thereby conferring on it probiotic traits.  相似文献   
999.
The presently licensed meningococcal vaccine is a tetravalent capsular polysaccharide vaccine that induces immunity to serogroups A, C, Y, and W-135 but not to group B, which causes nearly half of the meningitis cases in the United States. The purpose of this study was to evaluate the safety and immunogenicity of an intranasal native outer membrane vesicle (NOMV) vaccine prepared from a capsule negative strain of group B of Neisseria meningitidis. In this study all volunteers received the same dose of vaccine, but we evaluated two different immunization schedules and the oropharyngeal and intranasal routes of vaccine delivery, assessed nasal cytology for cellular infiltration, and measured antibody-secreting cells (enzyme-linked immunospot assay [ELISPOT]) as an early marker for systemic immune response. Additionally, both intranasal and serum vaccine-specific antibodies were measured as well as serum bactericidal activity. Four groups with a total of 42 subjects were immunized on days 0, 28, and 56. Group 3 received an additional dose on day 7. Group 2 subjects were immunized both intranasally and oropharyngeally. Group 4 received a different lot of vaccine. All groups received approximately 1,200 microg of vaccine per subject. Patients were evaluated for side effects. The vaccine was well tolerated without evidence of inflammation on nasal cytology. The group receiving the extra vaccine dose showed the maximum increase in bactericidal activity. Thirty of 42 subjects demonstrated an increase in meningococcus-specific intranasal immunoglobulin A (IgA) titers, while 23 of 42 demonstrated an increase in specific IgG titers. The group receiving vaccine intranasally and oropharyngeally showed the highest rise in intranasal titers for both IgA and IgG. Groups 1, 3, and 4 showed a significant increase in antibody-secreting cells on ELISPOT. Eighteen of 42 volunteers demonstrated a fourfold or greater rise in bactericidal titers, with 81% showing an increase over baseline. We have demonstrated the immunogenicity and safety of a group B lipopolysaccharide-containing, intranasal, NOMV vaccine.  相似文献   
1000.
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