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141.
Numerous studies have shown evidence of cerebral ventricular enlargement in schizophrenia and its relationship to severity of clinical symptoms and psychosocial dysfunction. In this large prospective study, 88 noninstitutionalized DSM-III-R schizophrenic patients were administered a CT scan and rated for positive and negative symptomatology and premorbid adjustment. The CT scans from 14 healthy controls were used for comparison of cerebral ventricular measures. Patients had an enlarged ventricle to brain ratio of the anterior portion of the lateral ventricles, the frontal horns, compared with controls. Patients with larger frontal horns had more severe negative symptoms and poorer premorbid childhood adjustment. The area of the main body of the cerebral lateral ventricles, though not elevated in patients, was correlated with the total number of prior hospitalizations. These results support the hypothesis of a structural and functional "frontal" deficit in schizophrenia.  相似文献   
142.
One of six patients in a 1960 paper on "Cerebellar syndrome in myxoedema" was subsequently found to have adenocarcinoma. General post-mortem revealed carcinomatosis and basal pneumonia. Neuropathological examination revealed the changes of multiple system atrophy. The relationship between hypothyroidism, carcinoma, and cerebellar, pontine and striatonigral degeneration is discussed.  相似文献   
143.
Objective  To test the activity of telithromycin against 1034 Streptococcus pneumoniae isolates from pediatric patients in ten centers from ten central and eastern European countries during 2000–2001, and to compare it with the activities of erythromycin A, azithromycin, clarithromycin, clindamycin, and quinupristin–dalfopristin.
Methods  The minimum inhibitory concentrations (MICs) of telithromycin, erythromycin A, azithromycin, clarithromycin, clindamycin, levofloxacin, quinupristin–dalfopristin and penicillin G were tested by the agar dilution method with incubation in air, and mechanisms of resistance to macrolides and quinolones were investigated.
Results  Strains were isolated from sputum, tracheal aspirates, ear, eye, blood, and cerebrospinal fluid. Among S. pneumoniae strains tested, 36% had raised penicillin G MICs (≥ 0.12 mg/L). Susceptibilities were as follows: telithromycin, quinupristin–dalfopristin and levofloxacin, ≥ 99%; clindamycin, 83%; and erythromycin A, azithromycin and clarithromycin, 78%. Of 230 (22.3%) erythromycin A-resistant S. pneumoniae strains, 176 (79.6%) had erm(B) , 38 (16.1%) had mef(A) , and 10 (4.3%) had mutations in 23S ribosomal RNA or in ribosomal protein L4. The rates of drug-resistant S. pneumoniae are high in all centers except Kaunas, Riga, and Prague.
Conclusion  Telithromycin had low MICs against all strains, irrespective of macrolide, azalide or clindamycin resistance. Ribosomal methylation was the most prevalent resistance mechanism among all resistant strains, except in Sofia, where the prevalence of the efflux mechanism was higher.  相似文献   
144.
A glass/silicon composite intracortical electrode array   总被引:5,自引:0,他引:5  
A new manufacturing technique has been developed for creating silicon-based, penetrating electrode arrays intended for implantation into cerebral cortex. The arrays consist of a 4.2 mm×4.2 mm glass/silicon composite base, from which project 100 silicon needle-type electrodes in a 10×10 array. Each needle is approximately 1,500 μm long, 80μm in diameter at the base, and tapers to a sharp point at the metalized tip. The technique used to manufacture these arrays differs from our previous method in that a glass dielectric, rather than ap-n-p junction, provides electrical isolation between the individual electrodes in the array. The new electrode arrays exhibit superior electrical properties to those described previously. We have measured interelectrode impedances of at least 1013 Ω, and interelectrode capacitances of approximately 50 fF for the new arrays. In this paper, we describe the manufacturing techniques used to create the arrays, focusing on the dielectric isolation technique, and discuss the electrical and mechanical characteristics of these arrays.  相似文献   
145.
Event-related potentials (ERPs) from 134 children were obtained at 3 and 8 years of age and recorded to a series of consonant-vowel speech syllables and their nonspeech analogues. The HOME inventory was administered to these same children at 3 and 8 years of age and the sample was divided into 2 groups (low vs. high) based on their HOME scores. Discriminant functions analyses using ERP responses to speech and non-speech analogues successfully classified HOME scores obtained at 3 and 8 years of age and discriminated between children who received low vs. high levels of stimulation for language and reading.  相似文献   
146.
We review our studies on the role of polycyclic aromatic hydrocarbon (PAH)-DNA adducts in breast cancer. Additionally we report on analyses of the reliability of the scoring procedures used with immunohistochemical assay for PAH-DNA adducts and of potential bias arising from the use of benign breast disease (BBD) controls. We conducted a case-control study utilizing two control groups: BBD controls who donated tissue and blood samples, and healthy controls who donated blood samples. In comparisons of tumor tissue from cases and benign tissue from BBD controls, increasing adduct levels were significantly associated with case-control status [odds ratio (OR) = 2.40, 95% confidence interval (CI) 1.18-4.92], whereas in comparisons of nontumor tissue from cases and benign tissue from BBD controls the association was nonsignificant (OR = 1.97, 95% CI 0.94-4.17). We also show among cases, but not among BBD controls, that the GSTM1 null genotype is associated with increased adduct levels in breast tissue. Our reliability study found the scoring procedures used with the immunohistochemical assay to have high reliability, 0.93 in nontumor, 0.82 in tumor, and 0.74 in benign tissues. However, we found that the technician significantly contributed to the total variability of a series of data. Finally, we did not find a consistent bias to the null associated with the use of BBD controls; however, BBD controls may overestimate the prevalence of family history of breast cancer compared to that of healthy controls (18% vs.14%). We hypothesize that the higher prevalence results from a referral bias and discuss how this may influence our results.  相似文献   
147.
Bronchopulmonary dysplasia is a chronic lung disease of premature human infancy that shows pathological features comprising varying sized areas of interstitial fibrosis in association with distorted large alveolar spaces. We have previously shown that transfer of active transforming growth factor (TGF)-beta 1 (AdTGF beta 1(223/225)) genes by adenovirus vector to embryonic lungs results in inhibition of branching morphogenesis and primitive peripheral lung development, whereas transfer to adult lungs results in progressive interstitial fibrosis. Herein we show that transfer of TGF-beta1 to newborn rat pups results in patchy areas of interstitial fibrosis developing throughout a period of 28 days after transfer. These areas of fibrosis appear alongside areas of enlarged alveolar spaces similar to the prealveoli seen at birth, suggesting that postnatal lung development and alveolarization has been inhibited. In rats treated with AdTGF beta 1(223/225), enlarged alveolar spaces were evident by day 21, and by 28 days, the mean alveolar cord length was nearly twice that in control vector or untreated rats. Hydroxyproline measurements confirmed the presence of fibrosis. These data suggest that overexpression of TGF-beta 1 during the critical period of postnatal rat lung alveolarization gives rise to pathological, biochemical, and morphological changes consistent with those seen in human bronchopulmonary dysplasia, thus inferring a pathogenic role for TGF-beta in this disorder.  相似文献   
148.
Prospects for a Vaccine for Clostridium difficile   总被引:1,自引:0,他引:1  
Clostridium difficile diarrhoea and colitis is a new disease that is attributable to broad spectrum antibiotic therapy. During the past 2 decades C. difficile has become one of the most common nosocomial pathogens in the developed world. As changing demographics create an increasingly elderly population and the use of broad spectrum antimicrobials continues to expand, C. difficile is likely to become increasingly problematic. Disease caused by this organism is caused by the inflammatory actions of its 2 toxins, A and B, on the intestinal mucosa. Human antibody responses to these toxins are common in the general population and in patients with C. difficile-associated disease. There is substantial, albeit inconclusive, evidence to indicate that antitoxin antibodies provide protection against severe, prolonged or recurrent C. difficile diarrhoea. Immunity induced by oral or parenteral passive administration of antibody is protective in animal models of C. difficile infection. In humans, intravenous passive immunisation with pooled human immunoglobulin has been successful in the treatment of recurrent and severe C. difficile colitis. Human trials of oral passive immunotherapy with bovine immunoglobulin therapy are in progress. Formalin-inactivated culture filtrate from toxigenic C. difficile, as well as purified and inactivated toxins, have been used to successfully immunise animals. Similar preparations are under investigation as possible human vaccines. Antibiotic therapy is effective in treating most individual patients with C. difficile diarrhoea, but has proven ineffective in reducing the overall incidence of nosocomial infection. Active immunisation is probably the most promising approach to long term control of this difficult iatrogenic disease.  相似文献   
149.
Cleft lip with or without cleft palate (CL/P) is the most common congenital malformation reported among infants of epileptic mothers. This study sought to examine the relative roles of anticonvulsant teratogenicity and other factors responsible for this association. Among 175 families with a proband with isolated CL/P, there were 13 parents with epilepsy and a high frequency of other family members with CL/P and epilepsy. Evaluation of the 13 cases suggested that teratogenicity of anticonvulsant drugs was not the primary factor responsible for the observed association of maternal epilepsy and clefting. Among 140 families with a proband with clefting other than CL/P, there were no instances of parental epilepsy observed.  相似文献   
150.
A study was conducted to compare the recovery of clinical isolates by the DuPont Isolator and Roche Septi-Chek blood culture systems. A total of 5,262 blood culture specimens were processed by the two systems. Of these, 358 cultures contained significant isolates: 219 were positive in both systems, 68 were recovered only by Isolator, 71 were recovered by Septi-Chek only (not statistically significant). Of the isolates recovered in both systems, 159 were positive the same day, 55 were recovered first by Isolator, and 5 were recovered first by Septi-Chek. In cases where Isolator recovered organisms first, the average difference in time was one to two days. Regarding particular groups of organisms, there was no difference between the systems in recovery of Enterobacteriaceae, anaerobes, yeast, and gram-positive bacteria, except for Streptococcus pneumoniae. Septi-Chek recovered S. pneumoniae significantly more often. These results suggest that these two systems are essentially comparable, except with S. pneumoniae, although the Isolator frequently provided results more rapidly.  相似文献   
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