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101.
OBJECTIVE: To examine the effect of 17beta-estradiol on the severity of the cardinal signs of PD in postmenopausal women. BACKGROUND: Although the impact of estrogens on the manifestations of PD has not been subjected to rigorous study, their use is generally thought to be associated with a detrimental antidopaminergic effect. METHODS: A double-blind, placebo-controlled, two-arm crossover study of high-dose transdermal 17beta-estradiol was conducted in eight postmenopausal women with mild to moderate PD, all but one of whom exhibited levodopa-induced dyskinesias. Patients were randomized initially to either hormonal treatment or placebo for 2 weeks, followed by a 2-week washout period, and then another 2-week crossover treatment period. Active treatment employed four skin patches each releasing 0.1 mg of estradiol daily, replaced every 2 to 3 days. RESULTS: After 10 days of treatment a significant reduction was observed in the antiparkinsonian threshold dose of IV levodopa. Mean duration and magnitude of the antiparkinsonian response to threshold or high doses of levodopa were unchanged, and dyskinesia scores were unaltered during 17beta-estradiol treatment compared with placebo. No worsening in "on" time or motor ratings with estrogen treatment was documented. CONCLUSIONS: 17beta-estradiol appears to display a slight prodopaminergic (or antiparkinsonian) effect without consistently altering dyskinesias. Standard postmenopausal replacement therapy with transdermal 17beta-estradiol is likely to be well tolerated by many female parkinsonian patients.  相似文献   
102.
A family of homologous proteins known as alpha-, beta-, and gamma-synuclein are abundantly expressed in brain, especially in the presynaptic terminal of neurons. Although the precise function of these proteins remains unknown, alpha-synuclein has been implicated in synaptic plasticity associated with avian song learning as well as in the pathogenesis of Parkinson's disease (PD), dementia with LBs (DLB), some forms of Alzheimer's disease (AD), and multiple system atrophy (MSA). Since olfactory dysfunction is a common feature of these disorders and the olfactory receptor neurons (ORNs) of the olfactory epithelium (OE) regenerate throughout the lifespan, we used antibodies specific for alpha-, beta-, and gamma-synucleins to examine the olfactory mucosa of patients with PD, DLB, AD, MSA, and controls without a neurological disorder. Although antibodies to alpha- and beta-synucleins detected abnormal dystrophic neurites in the OE of patients with neurodegenerative disorders, similar pathology was also seen in the OE of controls. More significantly, we show here for the first time that alpha-, beta-, and gamma-synucleins are differentially expressed in cells of the OE and respiratory epithelium and that alpha-synuclein is the most abundant synuclein in the olfactory mucosa, where it is prominently expressed in ORNs. Moreover, alpha- and gamma-synucleins also were prominent in the OE basal cells, which include the progenitor cells of the ORNs in the OE. Thus, our data on synuclein expression within the OE may signify that synuclein plays a role in the regeneration and plasticity of ORNs in the adult human OE.  相似文献   
103.

Purpose

The American Urological Association convened the Clinical Guidelines Panel on Erectile Dysfunction to analyze the literature regarding available methods for treating organic erectile dysfunction and to make practice recommendations based on the treatment outcomes data.

Materials and Methods

The panel searched the MEDLINE data base for all articles from 1979 through 1994 on treatment of organic erectile dysfunction and meta-analyzed outcomes data for oral drug therapy (yohimbine), vacuum constriction devices, vasoactive drug injection therapy, penile prosthesis implantation and venous and arterial surgery.

Results

Estimated probabilities of desirable outcomes are relatively high for vacuum constriction devices, vasoactive drug injection therapy and penile prosthesis therapy. However, patients must be aware of potential complications. The outcomes data for yohimbine clearly indicate a therapy with marginal efficacy. For venous and arterial surgery, based on reported outcomes, chances of success do not appear high enough to justify routine use of such surgery.

Conclusions

For the standard patient, defined as a man with acquired organic erectile dysfunction and no evidence of hypogonadism or hyperprolactinemia, the panel recommends 3 treatment alternatives: vacuum constriction devices, vasoactive drug injection therapy and penile prosthesis implantation. Based on the data to date, yohimbine does not appear to be effective for organic erectile dysfunction and, thus, it should not be recommended as treatment for the standard patient. Venous surgery and arterial surgery in men with arteriolosclerotic disease are considered investigational and should be performed only in a research setting with long-term followup available.  相似文献   
104.
To determine the reliability of concentric quadriceps muscle torque at 30 degrees , 60 degrees , and 75 degrees of knee extension, 25 female university students were studied. Each subject was tested on the Kin-Com isokinetic dynamometer on 2 separate days, 7 days apart. The dynamometer's speed was set at 60 degrees ls. Intraclass correlation coefficients for 30 degrees , 60 degrees , and 75 degrees were 0.84 (p<.01), 0.87 (p<.01), and 0.83(p<.01), respectively. The standard errors of the measure were 5.92 N.m, 7.65 N.m, and 7.35 N.m, respectively. Based on the instrumentation and protocol used in this study, we believe angle-specific torques have good reliability. Because of the error size, clinicians using similar methodology to determine angle-specific torques should be cautious when comparing differences between angle-specific torques of less than 12 to 16 N.m.  相似文献   
105.
106.
The surgical rehabilitation of a patient with severely deformed and functionally disabled genitalia due to long-standing lymphedema and infection is described and illustrated. The term "elephantiasis" has been applied to such gross lesions. Appropriate surgery to the penis, scrotum, and perineum has yielded a gratifying result. The principles and techniques of the surgical approach in such an undertaking are presented and discussed.  相似文献   
107.
Following consumption of a meal, 99% of the large food particles are emptied only after intragastric fragmentation has reduced their diameter to less than 2 mm. Anin vitro model was constructed to evaluate some of the factors which may play a role in the process of intragastric digestion. Gastric mixing of food was simulated in a silicone rubber tube (ID 19 mm) placed in a peristaltic pump. Peristaltic waves progressed upwards along the tube at a frequency of 0, 1, or 3/min, reducing the internal diameter of the tube to 5 mm. Cooked chicken liver particles (2–2.8 mm in diameter) were placed in the tube with one of the following: (1) 150 mM NaCl, (2) 150 mM HCl with or without pepsin, or (3) phosphate buffer at pH 7, 5.4, or 2.6 + pepsin. After 30 min, the extent of particle reduction and of solubilization of proteins were determined and expressed as percent of the initial liver weight. The diameter of liver particles was reduced to a greater extent in NaCl than in pH 7 buffer or acid solutions with or without pepsin. In contrast, the amount of proteins solubilized was enhanced two- to threefold by acid pepsin solutions compared to NaCl or pH 7 phosphate. The presentin vitro studies suggest that changes in motor and/or secretory activity of the stomach significantly modify intragastric digestion.  相似文献   
108.
109.
Pennsylvania is currently considering legislative options to expand coverage and improve access to medical care for state residents who lack health insurance. Relevant data are presented from a telephone survey of 10,809 Pennsylvania households. Almost nine percent (8.5%) of the state's population lacks health insurance, representing over one million people. Those most likely to be uninsured are children and young adults, non-whites and the poor. A substantial number of poor people are not covered by the state's Medicaid program. The uninsured report poorer health status, more obstacled to receiving care and greater use of hospital services for primary care.  相似文献   
110.
The distribution of neurofibrillary tangles (NFTs) and neuritic plaques (NPs) was mapped in 39 cortical areas of 11 brains of patients with Alzheimer's disease (AD). Whole hemisphere blocks were embedded in polyethylene glycol (Carbowax), sectioned coronally, and stained with thioflavin S and thionin. The densities of NFTs and NPs were assessed using a numerical rating scale for each area. Scores were grouped by type of cortex and by lobe for statistical analysis. Highly significant differences were obtained. For example, limbic periallocortex and allocortex had more NFTs than any other type of cortex. In descending order, the density of NFTs was as follows: periallocortex (area 28) greater than allocortex (subiculum/CA1 zones of hippocampal formation, area 51) greater than corticoid areas (accessory basal nucleus of amygdala, nucleus basalis of Meynert) greater than proisocortex (areas 11, 12, 24, 23, anterior insula, 38, 35) greater than nonprimary association cortex (32, 46, superior temporal sulcus, 40, 39, posterior parahippocampal cortex, 37, 36) greater than primary sensory association cortex (7, 18, 19, 22, 21, 20) greater than agranular cortex (44-5, 8, 6, 4) greater than primary sensory cortex (41-2, 3-1-2, 17). The laminar distribution of NFTs tended to be selective, involving primarily layers III and V of association areas and layers II and IV of limbic periallocortex. There were far more NFTs in both limbic and temporal lobes than in frontal, parietal, and occipital lobes. In general, NPs were more evenly distributed throughout the cortex, with the exceptions of limbic periallocortex and allocortex, which had notably fewer NPs than other cortical areas. Temporal and occipital lobes had the highest NP densities, limbic and frontal lobes had the lowest, and parietal lobe was intermediate. No significant left-right hemispheric differences for NFT or NP densities were found across the population, and there was no relationship between duration of illness and densities of NFTs or NPs. The regional and laminar distribution of NFTs (and, to a lesser degree, that of NPs) suggests a consistent pattern of vulnerability within the cerebral cortices that seems correlated to the hierarchies of cortico-cortical connections. The higher-order association cortices, especially those in the anterior and ventromedial sectors of temporal lobe, are the most vulnerable, while other cortices appear less vulnerable to a degree commensurate with their connectional "distance" (i.e., synapses removed) from the limbic areas.  相似文献   
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