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191.
Fluorescein angiography has been utilized to study the microvascular supply of the prelaminar optic disc and the peripapillary choroid. Observation of hypofluorescence of these structures both in patients with anterior ischemic optic neuropathy (AION) and with chronic open-angle glaucoma (COAG) has led to speculation as to the pathogenetic mechanism in each disorder. In AION, studies consistently show defective filling of the disc without atrophy, suggesting hypoperfusion as a primary mechanism. In COAG, defective filling is common, but typically occurs in regions of atrophy or increased cupping, which may show hypofluorescence as a nonspecific sequela of disc tissue loss. The hypofluorescence seen in some ocular hypertensive patients supports but does not confirm a primary vascular role in the pathogenesis of COAG. Peripapillary choroidal filling delay outside the range of normal is consistently seen in arteritic AION, but not in either nonarteritic AION or COAG. This finding suggests that any vasculopathy present in these disorders is distal within the branches of the posterior ciliary artery system.  相似文献   
192.
AION is the most common acute optic neuropathy in patients over 50 and, although the diagnosis is often straightforward, our methods for managing the associated visual loss are inadequate. Analysis of the wealth of information gained from recent clinical studies may move us closer to an effective therapy.  相似文献   
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Although it is commonly acknowledged that a diagnosis of cancer can be a form of a crisis precipitating a period of disequilibrium, few researchers have examined the psychosocial issues associated with the completion of adjuvant cancer treatment. This exploratory study examines the responses of women in a community-based cancer support group to an open-ended question asking them to describe their experiences since their treatment ended. Subjects were asked to respond to whether they felt the loss of the "safety net" of treatment had caused them any type of distress. The narrative responses of the subjects support the notion that the period after treatment ceases may be viewed as a crisis that brings with it anxiety and uncertainty. The results of this study reinforce the need for additional research to better understand the issue so that services and programs can be enhanced to better meet patients' needs. Additionally, the results suggest that social workers may play a crucial role in helping women make the transition from cancer "patient" to cancer "survivor."  相似文献   
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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   
198.
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   
199.
Marfan syndrome is an autosomal dominant connective tissue disorder characterized by skeletal, cardiovascular, and ocular anomalies. Ectopia lentis is the most common ocular manifestation. We report an ocular sign not previously described in Marfan syndrome, iridocorneal adhesions secondary to anterior lens subluxation. Three patients with the Marfan syndrome had iridocorneal adhesions on slit-lamp examination. One patient developed adhesions following treatment with pilocarpine. She underwent pars plana vitrectomy and lensectomy in both eyes due to progression of the iridocorneal adhesions. Treatment with miotics rotates the lens-iris diaphragm anteriorly and may contribute to the formation of such adhesions. The two other patients remained stable and did not received lensectomy or vitrectomy. Careful slit-lamp examination of the anterior segment should be conducted in patients with dislocated lenses.  相似文献   
200.

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   
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