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61.
Twenty four volunteers who had been allergic to laboratory animals for some years were examined by means of a questionnaire paying particular attention to symptoms associated with rats and by serological and skin tests with extracts of rat urine (retrospective study). Nasal and eye symptoms were reported by 21 and 16 individuals respectively: 13 had asthma. Positive skin tests and high levels of specific IgE antibody to rat urine extract were found in 17 of the more severely affected individuals and this group included 12 of those with asthma. Latent periods of work with animals before symptoms appeared varied from 0.5 to 12 years. Also 148 individuals were studied during their first year of work with animals (prospective study). Symptoms developing during the year were reported by 15%, asthma by 2%. IgE antibody levels to rat urine were raised in 40% of affected and 6% of the unaffected individuals but there was no significant correlation between symptoms and either antibody levels or positive skin tests. Allergic symptoms developing during the first year of postemployment were, on the whole, much milder than those seen in the retrospective study. A tentative conclusion is that most individuals who become allergic to laboratory animals develop the condition in a mild form during their first year of employment but it appears probable that atopic individuals, although having an equal chance of developing allergy as compared with non-atopic individuals, may eventually progress to a more severe form of the disease.  相似文献   
62.
Focal heavy charged particle irradiation of the rabbit brain created defined lesions which were observable by nuclear magnetic resonance (NMR) and positron emission tomography (PET) imaging techniques. The lesions appeared approximately 9-11 months after left partial hemibrain irradiation with 30 Gy (230 MeV/u helium ions), and were restricted to the white matter tracts and deep perithalamic and thalamic regions. 82Rubidium PET and Gadolinium DTPA enhanced NMR imaging were used to detect blood-brain barrier perturbations. 18Fluordeoxyglucose PET studies demonstrated widespread decreases in cerebral glucose uptake in the cortex and thalamus of the irradiated hemisphere. NMR and PET imaging results correlated well with histological findings. Rabbits irradiated with 15 Gy did not demonstrate any abnormalities in the brain with sequential NMR scans through 14 months post-irradiation.  相似文献   
63.
The action of papain and bromelain, prepared over a pH range from 4.6 to 8.6, was evaluated for the ability to render red cells agglutinable by five incomplete antibodies of differing blood group specificities using a two-stage technique. The optimal pH for treatment of red cells by activated papain or bromelain was between 5.4 and 5.8. Above this pH range, a fall in serological sensitivity was apparent which was much more pronounced with papain than with bromelain. The optimal pH for enzyme treatment of red cells can be achieved in two-stage techniques, but not in one-stage techniques due to the buffering effect of serum proteins.  相似文献   
64.
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L H Phillips 《Neurology》1986,36(9):1251-1253
Long thoracic nerve palsy causes weakness of the serratus anterior muscle and winging of the scapula. It is usually traumatic in origin. Isolated long thoracic nerve palsy has not been recognized as the major manifestation of familial brachial plexus neuropathy, but I have studied the syndrome in four members of three generations of one family. One individual suffered an episode of facial paresis. The inheritance pattern was autosomal dominant.  相似文献   
66.
The role of target cell transferrin receptors (TfR) in natural killer (NK) cell-induced cytolysis has been studied using Colo 205 cells in which prior exposure to 60 Hz electromagnetic fields produced constitutive expression of maximum numbers of TfR. It was found that NK cell cytolysis was decreased in those cells expressing the highest levels of TfR, while cells expressing the lowest level of TfR were lysed to the greatest extent. Furthermore, pretreatment of target cells with, and the continued presence in the assay medium of, iron transferrin produced, in general, only a slight decrease in cytolysis. Incubation of cells with apotransferrin also produced only a slight decrease in cytolysis, while incubation with zinc transferrin produced a greater decrease in cytolysis. This latter effect was particularly dramatic for cells that had been exposed previously to either a 60 Hz magnetic field alone (1.0 gauss) or to a combined electric + magnetic field (current density 300 mA/m2, 1.0 gauss). In addition to indicating a discordance between TfR expression on target cells and their sensitivity to NK cell cytolysis, the data presented provide a further indication of cellular membrane changes produced by exposure to 60 Hz electromagnetic fields.  相似文献   
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68.
Abstract:  The risks of developing malignant melanoma (MM) include ultraviolet irradiation and genetic factors. To examine the contribution of rare and common variation within known MM genes in sporadic US MM patients, coding regions of known MM susceptibility genes [cyclin-dependent kinase inhibitor 2A ( CDKN2A ), cyclin-dependent kinase 4, melanocortin 1 receptor ( MC1R ) and tyrosinase ( TYR )] were resequenced in 109–135 MM cases. The significance of variants was examined by comparing their frequencies in 390 cancer-free controls. Potential deleterious mutations in CDKN2A were found in two patients and two others had variants of unknown significance. Cases were more likely than controls to harbour the MC1R 'R' variants known or predicted to alter its function ( P  = 0.002), particularly the R160W variant ( P  = 0.0035). The associated TYR R402Q variant (rs1126809*A) was found in 29% of cases, similar to what has been described previously. One MM patient with a family history of MM, who had developed other skin cancers, was homozygous for a novel TYR variant (P406L) of unknown significance. Hence, rare variants in TYR may be important risk factors for skin cancer.  相似文献   
69.
ObjectiveWe examine remission rate probabilities, recovery rates, and residual symptoms across 36 weeks in the Treatment for Adolescents with Depression Study (TADS).MethodThe TADS, a multisite clinical trial, randomized 439 adolescents with major depressive disorder to 12 weeks of treatment with fluoxetine, cognitive–behavioral therapy, their combination, or pill placebo. The pill placebo group, treated openly after week 12, was not included in the subsequent analyses. Treatment differences in remission rates and probabilities of remission over time are compared. Recovery rates in remitters at weeks 12 (acute phase remitters) and 18 (continuation phase remitters) are summarized. We also examined whether residual symptoms at the end of 12 weeks of acute treatment predicted later remission.ResultsAt week 36, the estimated remission rates for intention-to-treat cases were as follows: combination, 60%; fluoxetine, 55%; cognitive–behavioral therapy, 64%; and overall, 60%. Paired comparisons reveal that, at week 24, all active treatments converge on remission outcomes. The recovery rate at week 36 was 65% for acute phase remitters and 71% for continuation phase remitters, with no significant between-treatment differences in recovery rates. Residual symptoms at the end of acute treatment predicted failure to achieve remission at weeks 18 and 36.ConclusionsMost depressed adolescents in all three treatment modalities achieved remission at the end of 9 months of treatment.  相似文献   
70.
Contrary to popular beliefs, a recent empirical study using eye tracking has shown that a non-clinical sample of socially anxious adults did not avoid the eyes during face scanning. Using eye-tracking measures, we sought to extend these findings by examining the relation between stable shyness and face scanning patterns in a non-clinical sample of 11-year-old children. We found that shyness was associated with longer dwell time to the eye region than the mouth, suggesting that some shy children were not avoiding the eyes. Shyness was also correlated with fewer first fixations to the nose, which is thought to reflect the typical global strategy of face processing. Present results replicate and extend recent work on social anxiety and face scanning in adults to shyness in children. These preliminary findings also provide support for the notion that some shy children may be hypersensitive to detecting social cues and intentions in others conveyed by the eyes. Theoretical and practical implications for understanding the social cognitive correlates and treatment of shyness are discussed.  相似文献   
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