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61.
62.
Two adults with mild dementia and a history of memory loss and disequilibrium were seen in the eye clinic following complaints of acuity loss in the 20/30–20/70 (Snellen) range. Results from the fundus examination of one patient were entirely normal; the other showed minimal vascular attenuation and optic atrophy. Electrophysiology was remarkable: (1) Photopic ERG b-waves were reduced, delayed, and showed pronounced oscillations. (2) EOG light-rise potentials were absent or very small. (3) Binocular pattern-VER signals showed addition of the monocular signal. Scotopic ERG signals were normal. Brain biopsy and microscopy showed intercellular, autofluorescent ceroid deposits which provided a clear diagnosis of Kufs disease. Histology of model animal retinal cells show ceroid deposits in cell classes implicated by the human retinal signals. The cluster of electrophysiological results point toward early changes in the pigment epithelium and inner plexiform layer cells as a means of non-invasive diagnosis.  相似文献   
63.
The wave I-wave V delay in the auditory brain-stem response is commonly used as a diagnostic tool in otoneurology. Normative values have been established for different populations and different types of stimuli. This I-V delay has been known for some time as "central conduction time" or "central transmission time." This implies that the measure reflects in normal and in pathologic cases delays due to nerve conduction, synaptic transmission, and neural integration and is not caused by cochlear processes. By virtue of the traveling wave delay in the cochlea, amounting to some 4 ms from the base to the "500-Hz place," it is conceivable that this delay contributes to the I-V delay. From a series of 69 pontine angle tumors in which the auditory brain-stem response was recorded, we selected cases with an apparent peripheral origin of a prolonged I-V delay by comparing the whole-click response to responses derived from high-pass noise masking. It seems that cases with an increased I-V delay in the whole-click response but (almost) normal I-V delays in the narrow-band response are indicative of small intracanalicular acoustic neuroma.  相似文献   
64.
Summary The pharmacokinetics of vindesine were investigated during treatment of 15 patients with progressive malignancies refractory to conventional treatment. Patients were administered one of three IV dose schedules: 3.0 mg/m2 bolus injection, 1.2 mg/m2/day infusion for 5 days, or 2.0 mg/m2/day infusion for 2 days. Concentrations of the drug in the serum and urine were determined by radioimmunoassay. Serum concentrations were highest (5×10-7 M) in patients receiving a bolus injection, but fell to nondetectable levels by 48 h in four of five patients (terminal t1/2 15.0±9.4 h). Compared with bolus injection, 1.2-to 1.4-fold greater areas under the blood concentration curve were observed during infusions of 2.0 mg/m2 and 1.2 mg/m2. Whereas steady-state concentrations (1×10-8 M) were maintained throughout the infusion of 1.2 mg/m2/day progressively increasing serum levels were observed during the infusion of 2.0 mg/m2/day. Serum concentrations fell rapidly following discontinuation of the 2.0-mg/m2 infusion, but were somewhat more sustained in the 1.2-mg/m2 infusion group. The average urinary excretion was similar for each dose-schedule (8%–11% of the total dose). The pharmacokinetics of vindesine are influenced by variations in dose schedule.  相似文献   
65.
Jan Hendrik Louw (1915–1992), considered the father of pediatric surgery in South Africa, gained prominence for his work on congenital intestinal atresia, a condition that had a mortality as high as 75 percent. His hypothesis, that jejunoileal atresia arose from mesenteric circulatory accidents in utero, was the dominant view until recent research uncovered the involvement of genetic and embryological mechanisms. In the mid-1950s he was one of a number of surgeons to resect the enlarged bulbous segment proximal to the site of the atresia, a crucial step in the surgical approach to intestinal atresia that brought mortality below 10 percent. A world leader in surgery as chair of surgery at the Groote Schur Hospital in Cape Town for more than a quarter century, his work in surgical research took root from his private tragedy early in his career of the death of his own infant son of intestinal atresia, a condition to which he would contribute so much.  相似文献   
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67.
Patients undergoing evaluation for solid organ transplantation (SOT) often have a history of malignancy. Although the cancer has been treated in these patients, the benefits of transplantation need to be balanced against the risk of tumor recurrence, especially in the setting of immunosuppression. Prior guidelines of when to transplant patients with a prior treated malignancy do not take in to account current staging, disease biology, or advances in cancer treatments. To develop contemporary recommendations, the American Society of Transplantation held a consensus workshop to perform a comprehensive review of current literature regarding cancer therapies, cancer stage-specific prognosis, the kinetics of cancer recurrence, and the limited data on the effects of immunosuppression on cancer-specific outcomes. This document contains prognosis based on contemporary treatment and transplant recommendations for breast, colorectal, anal, urological, gynecological, and nonsmall cell lung cancers. This conference and consensus documents aim to provide recommendations to assist in the evaluation of patients for SOT given a history of a pretransplant malignancy.  相似文献   
68.
Remote interventions are increasingly used in transplant medicine but have rarely been rigorously evaluated. We investigated a remote intervention targeting immunosuppressant management in pediatric lung transplant recipients. Patients were recruited from a larger multisite trial if they had a Medication Level Variability Index (MLVI) ≥2.0, indicating worrisome tacrolimus level fluctuation. The manualized intervention included three weekly phone calls and regular follow-up calls. A comparison group included patients who met enrollment criteria after the subprotocol ended. Outcomes were defined before the intent-to-treat analysis. Feasibility was defined as ≥50% of participants completing the weekly calls. MLVI was compared pre- and 180 days postenrollment and between intervention and comparison groups. Of 18 eligible patients, 15 enrolled. Seven additional patients served as the comparison. Seventy-five percent of participants completed ≥3 weekly calls; average time on protocol was 257.7 days. Average intervention group MLVI was significantly lower (indicating improved blood level stability) at 180 days postenrollment (2.9 ± 1.29) compared with pre-enrollment (4.6 ± 2.10), = .02. At 180 days, MLVI decreased by 1.6 points in the intervention group but increased by 0.6 in the comparison group (= .054). Participants successfully engaged in a long-term remote intervention, and their medication blood levels stabilized. NCT02266888.  相似文献   
69.
A growing but limited body of research has identified the college student population as one that is particularly vulnerable to food insecurity. Early estimates of food insecurity prevalence among college students range from 14 to 60 per cent. The present study utilises original survey data collected from a random sample (n = 300) of college students enrolled at an urban university in the Midwest region of the United States of America (USA). This study examines the impact of food insecurity on health outcomes and the mediation of this relationship by subjective social status among college students. Ordinary least squares (OLS) and logistic regression analyses find that food insecurity is related to worse self-rated, physical and mental health among college students, and Sobel-Goodman tests find that subjective social status plays a significant mediating role in the relationship between food insecurity and health among college students. The implications of these findings in a university context are discussed using a psychosocial framework and insights from the stress process model. In doing so, I discuss food insecurity among college students with an emphasis on the social significance of food and food insecurity.  相似文献   
70.
The COVID‐19 pandemic continues to be a major public health threat globally and low‐ and middle‐income countries (LMICs) are not an exception. The impact of the COVID‐19 pandemic is far‐reaching on many areas including but not limited to global health security, economic and healthcare delivery with a potential impact on access to healthcare in LMICs. We evaluate the impact of the COVID‐19 pandemic on access to healthcare in LMICs, as well as plausible strategies that can be put in place to ensure that the delivery of healthcare is not halted. In order to mitigate the devastating effect of the COVID‐19 pandemic on the already weak health systems in LMICs, it is much necessary to reinforce and scale up interventions and proactive measures that will ensure that access to healthcare is not disrupted even in course of the pandemic.  相似文献   
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