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81.
Summary Four tumors of the spinal cord were induced with ethylnitrosourea in rats by transplacental administration and transplanted into the brains of animals of the same strain. One of these intracerebrally grafted tumor lines (G-XIII) was followed up over the first 10 passages and treated with CCNU and other alkylating drugs. The results were compared with findings in an earlier established line (G-XII) in passage 12 and 59, which in the first instance was sensitive to CCNU. The CCNU application prolonged survival in treated animals in various treatment schedules in the first 10 intracerebrally grafted generations of the tumor up to 59%. Induction times of tumors became increasingly shorter. The susceptibility of early passages was similar in both lines. Its loss in late passages went together with diffuse growth of the tumor and reticulin fiber production. In addition, glial fibrillary acid protein expression and formation of intermediate filaments in perivascular tumor cells was lost.  相似文献   
82.
This pilot study compared abdominal massage with laxative treatment in the management of constipation in 32 profoundly disabled, institutionalised adults. A randomised cross-over design was used. After an initial 16-day baseline measurement phase without any treatment, there followed two seven-week treatment phases separated by a one-week washout period. Each subject received seven weeks of massage and seven weeks on his or her previous laxative regimen. Primary outcome measures were gastro-intestinal and segmental transit times, measured at the end of the baseline phase and of each treatment phase. Secondary measures included stool frequency, size and consistency, the requirement for enemas and an assessment of patient well-being.The median value of total colonic transit time was 183 hours for the baseline phase and 159 hours for all treatment phases. There was no evidence of any statistically significant treatment differences between laxative and massage therapy for right, left or rectosigmoid segments either separately or in total. Analysis of secondary outcome measures also failed to find any treatment preferences.These results reveal the grossly abnormal colonic transit times of the study population at all times. The effects of laxative and massage therapy within this environment were not demonstrably different.  相似文献   
83.
Histopathologic evidence of central nervous system involvement with cytomegalovirus (CMV) has been well recognized in patients infected with human immunodeficiency virus (HIV). However, clinically symptomatic disease has been decidedly less common. In this report, we describe a patient infected with HIV who developed an acute change in neurological status. Gadolinium-enhanced magnetic resonance imaging and analysis of cerebrospinal fluid revealed CMV ventriculitis and meningoencephalitis. Treatment with ganciclovir resulted in radiological improvement of the ventriculitis and negative CMV cultures but little clinical neurological improvement.  相似文献   
84.
Abstract Factors influencing the remarkable growth of home health care include increased elderly population, decreased average length of hospital stay, and technological advancements that reduce the need for hospitalization. Societal changes have prompted increasing concern about personal risk to home care providers. The purpose of this pilot study was to: 1) ascertain factors related to perception of risk by home health care administrators and staff and to identify strategies used by home health care administrators to reduce risk to staff; and 2) determine whether quality of care is affected when home-visit situations present risk. A convenience sample of 36 home health care administrators and 62 staff was surveyed about risks and measures provided by the home health care agency to minimize risk. Factors associated with risk are geographic location, high incidence of crime, inappropriate patient or caregiver behavior, infectious diseases, and evening assignments. Strategies used to minimize risk include safety programs, preplanning of visits, personal protective equipment, escorts, and buddy systems. Perceived ability to refuse high-risk assignments, however, is questionable, as 66% of the staff stated that they leave a situation "as soon as possible." These findings will be used to strengthen inservice programs and to provide a basis for future studies.  相似文献   
85.
86.
We report on a 45-year-old man with a history of multiple psychiatric admissions for a gait disorder and episodic weakness thought to be psychogenic who was subsequently diagnosed with status cataplecticus due to narcolepsy. The gait difficulties resolved with venlafaxine. This case demonstrates that status cataplecticus can be misdiagnosed as a psychogenic gait disorder.  相似文献   
87.
Partial k-space sampling is frequently used in single-shot diffusion-weighted echo-planar imaging (DW-EPI) to reduce the TE and thereby improve the SNR. However, it increases the sensitivity of the technique to bulk rotational motion, which introduces a phase gradient across the tissue that shifts the echo in k-space. If the echo is displaced into the high spatial frequencies, conventional homodyne reconstruction fails, causing intensity oscillations across the image. Zero-padding, on the other hand, compromises the image resolution and may cause truncation artifacts. We present an adaptive version of the homodyne algorithm that detects the location of the echo in k-space and adjusts the center and width of the homodyne filters accordingly. The adaptive algorithm produces artifact-free images when the echo is shifted into the high positive k-space range, and reduces to the standard homodyne algorithm in the absence of bulk motion.  相似文献   
88.
Digital dermatoglyphics of a sample from the Basque Valley of Salazar, situated in the West of the Pyrenees, were analysed. The results showed bimanual differences in both sexes, and also sexual differences for both hands. The comparative study with other Basque valleys showed that, in spite of their supposed common origin, the geographic barriers and the isolation have generated a genetic/dermatoglyphic and linguistic differentiation.  相似文献   
89.
Seven systems for the diagnosis of schizophrenia were compared in their ability to predict short-term outcome at follow-up: with each other, with selected specific symptoms, and with a simple additive composite symptom score. None of the systems nor the symptoms predicted strongly, but DSM-III and Schneiderian First Rank Symptoms and the composite score performed somewhat better than the other predictors.  相似文献   
90.
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