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151.
152.
This investigation evaluated a behavioral means of identifying sources of happiness and unhappiness among individuals with profound multiple disabilities. Indices of happiness and unhappiness were defined, and a corresponding observation system was developed and implemented with five students in an adult education classroom. Each student was observed while participating in two separate classroom activities. Results indicated the definitions and the observation system reliably identified different frequencies of happiness and/or unhappiness indices for each student across separate activities. Results are discussed regarding routine use of the observation system to evaluate classroom activities for effects on student happiness as a measure of quality of life. Future research needs are discussed in terms of determining means to alter certain classroom procedures that are accompanied by indices of student unhappiness.  相似文献   
153.
Reid E 《Journal of neurology》1999,246(11):995-1003
The hereditary spastic paraplegias are a complex group of neurodegenerative conditions which are characterised by slowly progressive lower limb spasticity. This article describes the main clinical features of pure and complicated hereditary spastic paraplegias and summarises recent advances in our understanding of the molecular genetics of these conditions. Received: 2 June 1999 Accepted: 7 August 1999  相似文献   
154.
To understand the clonal relationship of various olfactory bulb (OB) cell types, OB progenitor cells were infected at embryonic day (E) 14, E15, and E17 with retroviral libraries encoding alkaline phosphatase or beta-galactosidase. After survival to postnatal day 10-15, sibling relationships were identified by polymerase chain reaction DNA amplification of distinct sequences in the retroviral constructs. Within the OB, clonal progeny dispersed widely in all directions. In sharp contrast, however, clonal dispersion between the OB and neocortex was not observed, although occasional clonal dispersion between the OB and pyriform and hippocampal regions could not be excluded. Most clones (84%) contained a single cell type, especially after E17 injections, suggesting the existence of either restricted precursors, or multipotential progenitors instructed by a restricted cellular environment. Mixed OB clones (16%) contained multiple cell types in the OB, or occasionally glial or neuronal cells outside the OB, demonstrating the existence of multipotential OB progenitors, likely at a stage before formation of the olfactory rostral migratory stream. Surprisingly, OB glial cells were not labeled, suggesting distinct lineages or perhaps distinct migratory paths for glia and neurons into the OB. A hierarchical cell lineage is proposed that involves a multipotential progenitor that gives rise to potentially more limited progenitors.  相似文献   
155.
The purpose of this study is to determine the individual contribution, or importance number, of the symptoms to an analysis of depression, utilizing a neural network model. In addition, the presence of hopelessness and somatic complaints was examined, to determine their relevance to depression. Using Wave 1 data from Duke University's contribution in the Epidemiological Catchment Area (ECA) study, we created a mathematical model, a neural network, to map the relationship of nine symptoms of major depression, hopelessness and somatic complaints to the presence or absence of the formal diagnosis of depression, and performed a contribution analysis. The contribution analysis using the neural network revealed that the symptoms with the greatest impact on the occurrence of depression, or with the largest importance number for depression, were sadness, loss of interest, tiredness and sleeping trouble, in that order. The most frequently reported symptoms, though, were sadness, sleeping trouble, suicidal ideation, tiredness and poor concentration, in that order. Hopelessness and somatic symptoms were the lowest in their contribution to the diagnosis of depression. The study thus provides the hierarchy of the symptoms of depression and supports the DSM classification of major depression.  相似文献   
156.
The objective of this paper was to determine the time course and extent of platinum uptake into human malignant glioma tissue. An intraoperative, intravenous infusion of carboplatin was given to nine patients (seven glioblastoma and two anaplastic glioma) undergoing tumour excision. Carboplatin dosage was calculated individually to achieve a target systemic free carboplatin exposure. Tumour and peritumoural tissue was harvested at timed intervals following carboplatin administration. Plasma and tumour platinum concentrations were measured by graphite furnace flameless atomic absorption spectrophotometry. Histological examination was also performed on a piece of each tissue sample. The mean carboplatin dose administered was 783, SEM 56 mg (range 485-903). Plasma pharmacokinetics showed a typical elimination curve. The mean peak plasma platinum concentration was 44, SEM 5 micrograms/ml (range 27-74). The mean total elemental plasma platinum area under the curve (AUC) was 9.0, SEM 1.4 mg/ml/min. Platinum was detected in 61 tumour samples, the mean peak concentration being 13 SEM 2 micrograms/g (range 5-21). Platinum was also detected in peritumoural brain and necrotic tumour. No correlation was apparent between the degree of necrosis in each tumour specimen and tumour platinum concentration. Platinum concentrations achieved in tumour were similar to levels that would be cytotoxic for glioma cells in vitro. The results of this study have implications for future studies using capillary permeability modifying agents as adjuncts to brain tumour chemotherapy.  相似文献   
157.
A 33-year-old man presented with a history of fits and on initial investigation was suspected of having a left frontal parafalcine meningioma. Initial surgical procedure to excise the lesion had to be abandoned owing to the extreme vascularity of the lesion. Histology revealed it to be a haemangioendothelioma. At a second operation the tumour was completely removed. The histology of this rather uncommon tumour is discussed and the literature is reviewed.  相似文献   
158.
To try and determine any presence of cross-infection between patients, prospective screening of 226 consecutive admissions on our burns unit was performed by taking nose, throat and wound swabs. Infected wounds were also swabbed and a correlation was sought between the organisms cultured on screening swabs and those responsible for infection. We did not find any evidence of cross- infection occurring between the burns patients and the other categories of patients on the ward. Screening swabs were useful in detecting carriers, who were found to be more of a risk to themselves than to other patients on the unit.  相似文献   
159.
Prosthetic reconstruction of the femur for primary bone sarcoma   总被引:1,自引:1,他引:0  
The survival of patients and implants, complications and functional outcome were reviewed in 25 consecutive femoral endoprosthetic reconstructions for treatment of primary bone sarcoma. The diagnosis was chondrosarcoma in 11, osteosarcoma in 10, MFH in 3 and Ewing’s tumour in 1. Median follow up was 64 months (34 to 219) and median age at operation was 29 years (10 to 70). Twelve remained disease free at review. One had amputation for local recurrence and another was alive with metastases. 11 patients died at a median of 13 months (5 to 128); 8 from metastatic disease and 3 from other causes. Four implants were revised, at a median of 95 months (53 to 136); two for fractures of the stem and two for aseptic loosening. Three implants had radiological evidence of loosening at a median of 43 months (34 to 49). Fourteen patients had significant complications. The median functional score using the Musculoskeletal Tumour Society system was 68%. In our experience, prosthetic reconstruction of the femur does not compromise survival, although there is a significant complication rate.
Résumé  La survie des patients et des implants, les complications et le résultat fonctionnel ont étéétudiés dans 25 reconstructions prothétiques fémorales consécutives au traitement de sarcomes primaires de 1’os. Le diagnoctic était : ostéosarcome dans 11 cas, chondrosarcome dans 10, MFH dans 3 et tumeur d’Ewing dans 1. La médiane de suivie était de 64 mois (34 à 219) et la valeur médiane de 1’age à 1’opération était de 29 ans (10 à 70). 12 patients sont sans métastase ni récidive à la revue. Un a eu une amputation pour récidive locale et un autre est vivant avec métastases. 11 patients sont morts avec une médiane de 13 mois (5 à 128): 8 de méastases et 3 d’autres causes. 4 implants ont été réopérés avec une médiane de 95 mois (53 à 136) : 2 pour rupture de la tige et 2 pour descellement aseptique. 3 implants montraient un descellement radiologique à une médiane de 43 mois (34 à 49). 14 patients avaient des complications notables. Le score fonctionnel moyen utilisant la cotation de la Musculoskeletal tumor Society était de 68%. La reconstruction prothétique du fémur ne compromet pas la survie bien qu’il y ait un taux élevé de complications.


Accepted: 16 August 1999  相似文献   
160.
There are perhaps five strategies either presently advocated or under investigation for prevention of recurrent urinary tract infection (UTI): antibiotics, including natural peptides; functional foods; vaccines; probiotics; and miscellaneous, including avoidance of spermicides and maintenance of good hygiene. It is not possible to state the proportion of patients using antibiotics versus foods such as cranberry or using alternative approaches such as avoidance of spermicides. The majority of women who are referred to specialists will be prescribed long-term, low-dose antibiotics. However, given the magnitude of the problem, it is safe to state that large numbers of women are at least experimenting with alternative remedies such as drinking of cranberry juice or ingestion of herbal remedies with a view to enhancing their immune response. Vaccine development remains a long way from human use and has yet to be developed for organisms other than Escherichia coli. The use of probiotics to restore the normal vaginal flora and provide a competitive bacterial barrier to pathogens is close to becoming available as an alternative preventive approach. The next decade should see the introduction of new methods for reduction of the high incidence of UTI and better management of recurring urogenital infections.  相似文献   
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