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21.
The use of ibuprofen by patients with systemic lupus erythematosus poses a major threat of aseptic meningitis. Although previously reported cases have all been in young adults, our case of ibuprofen-induced meningitis occurred in a 73-year-old woman. This report greatly expands the age population that may suffer meningitis from this analgesic, now available over the counter, and emphasizes the importance of recognizing this causative relationship in patients with headache.  相似文献   
22.
Auricular chondritis occurred in a patient following a course of auricular acupuncture administered to help the patient give up smoking. Despite immediate treatment the condition pursued a long course resulting in considerable morbidity and some deformity of the ear. Twenty months after presentation the ear is not completely stable. Acupuncture should be considered a form of penetrating trauma which may induce perichondritis or chondritis in the auricle.  相似文献   
23.
Synaptic physiology of horizontal connections in the cat's visual cortex.   总被引:13,自引:0,他引:13  
Horizontal connections are a principal component of intrinsic cortical circuitry. They arise mainly from pyramidal cells and course parallel to the brain's surface for distances as long as 8 mm, linking columns with shared orientation preference and allowing cells to integrate visual information from outside their receptive fields. We examined the synaptic physiology of the horizontal pathway in slices of the cat's striate cortex and found that activating lateral fibers produced both excitation and inhibition. We recorded the postsynaptic responses of identified pyramidal cells in layer 2 + 3 of area 17 to electrical shocks applied at three sites: in the home column of the impaled neuron either in layer 2 + 3 or 4, or at a lateral distance of 0.9-3 mm in layer 2 + 3. Within the home column, suprathreshold stimuli produced compound EPSPs with action potentials, followed by fast, GABAAergic IPSPs and a slower, GABABergic IPSP. For the distant stimulating site, the threshold response was an EPSP. Stronger shocks frequently evoked a disynaptic, GABAAergic IPSP that truncated the EPSP and could dominate the postsynaptic response. At the resting potential, the horizontally evoked EPSP was too small to elicit spikes. With depolarization of the membrane, however, it grew several hundred-fold. This amplification was blocked by N-(2,6-dimethylphenylcarbamoylmethyl)triethylammonium bromide (QX-314), but not by 2-amino-5-phosphonovalerate (APV), indicating that it was mediated by Na+ channels, rather than by NMDA receptors. We propose that the horizontal connections provide the means for stimuli outside the receptive field to modulate activity elicited within its confines. The voltage-dependent enhancement of the laterally evoked EPSP may explain why stimulating the surround by itself fails to drive cells but can facilitate their response to stimuli within the receptive field. The ability to initiate disynaptic inhibition from lateral sites shows that recruiting appropriate groups of horizontal fibers can also have a suppressive effect. Thus, the effect of horizontal input is state dependent, with the size and sign of the laterally evoked response changing according to the balance of converging inputs.  相似文献   
24.
Veterans who were eligible for dental care in Department of Veterans Affairs (VA) facilities at no monetary cost responded to a mailed questionnaire. Seventy-one percent were aware that they were actually eligible for VA dental care. However, only 48 percent reported the VA as their only or primary source of dental care. Eligibility status, perceived quality of VA dental care, use of VA medical care, perception that one's income meets expenses, and perceived need for dental care were significant correlates of using the VA as one's current source of dental care. Level of formal education, perception that one's income meets expenses, transportation pattern, geographic distance from a VA facility, and eligibility status were significant correlates of using the VA as one's current medical care source. Research on VA utilization offers the opportunity to study issues of access to, and use of, a large public health care system whose patients largely receive care at no monetary cost. Veterans' use of VA dental and medical care is apparently influenced by a wide variety of factors, ranging from barriers to access to non-VA systems, to characteristics of the VA delivery system itself, to need for treatment.  相似文献   
25.
Amyotrophic lateral sclerosis (ALS) is a relentlessly progressive and fatal motor neuron disease. We carried out two randomized, double-blind, placebo-controlled, multi-centre, multi-national studies with xaliproden (a drug with neurotrophic effect) to assess drug efficacy and safety at two doses. Patients with clinically probable or definite ALS of more than 6 months and less than 5 years duration were randomly assigned to placebo, 1 mg or 2 mg xaliproden orally once daily as monotherapy in Study 1 (n=867); or to the same regimen with addition of riluzole 50 mg bid background therapy in Study 2 (n=1210 patients). The two primary endpoints were defined as: 1. Time to death, tracheostomy, or permanent assisted ventilation (DTP), and 2. Time to vital capacity (VC)<50% or DTP before (log-rank test) and after adjustment using a Cox proportional hazard model for prespecified prognostic factors. Secondary endpoints were rates of change of various functional measures. In Study 1, primary outcome measures did not reach statistical significance. For the 2 mg group, for time to VC<50% analysis (without DTP) a significant 30% RRR was obtained (95% confidence interval [CI]: 8.46, P=0.009). In Study 2, no significant results were obtained. However, there was a trend in favour of add-on 1 mg dose xaliproden vs. placebo (RRR 15% [-6.31, ns] for time to VC<50%; RRR 12% [CI: -6.27, ns] for time to VC<50% or DTP). Adjusted RR ratios were consistently more favourable for the xaliproden groups. Tolerability was good, and dose-dependent side effects were largely associated with the serotonergic properties of xaliproden. An effect of xaliproden on functional parameters, especially VC, was noted. Although this effect did not reach statistical significance, xaliproden had a small effect on clinically noteworthy aspects of disease progression in ALS.  相似文献   
26.
A randomized trial of a family physician intervention for smoking cessation   总被引:13,自引:0,他引:13  
We assessed the impact of three conditions on one-year smoking cessation rates. Physicians in 70 community general practices were randomly allocated by practice to one of three groups: In the usual care group, smoking patients were to receive the care they normally would receive. In the gum only group, physicians were asked to speak to patients about smoking cessation and offer nicotine gum. In the gum plus group, physicians were trained in the experimental intervention. This intervention involved advice to stop smoking, the setting of a quit date, the offer of nicotine gum, and four follow-up visits. Smoking cessation was measured by self-report after one year and validated using saliva cotinine measures. Using a criterion of at least three months of abstinence, 8.8% of the patients of the trained physicians had stopped smoking at the one-year follow-up compared with 4.4% and 6.1% of the patients in the usual care and gum only groups, respectively.  相似文献   
27.
Nerve biopsy findings in Niemann-Pick type II (NPC)   总被引:1,自引:0,他引:1  
The severe infantile form of Niemann-Pick disease type II was diagnosed in a 4-year-old girl and confirmed by demonstrating in cultured skin fibroblasts a deficiency of low-density lipoprotein-stimulated cholesterol ester synthesis of < 5% of normal. Electrodiagnostic studies revealed changes of a predominantly demyelinating motor and sensory polyneuropathy. Light microscope and ultrastructural examination of a peroneal nerve biopsy showed unique changes. Compacted myelin sheaths were disproportionately thin with marked globular irregularities in single teased nerve fibres and evidence of chronic demyelination. The majority of axons were preserved but axonal spheroids and cytoskeletal abnormalities akin to neuroaxonal dystrophy were noted. Membrane-bound multilobulated lysosomal inclusions of floccular and electron-dense material were present in Schwann cells (SC), endoneurial fibroblasts, macrophages, pericytes and endothelial cells. SC of myelinated fibres were stuffed with whorls of concentric osmiophilic membranous profiles and electron-lucent material. The findings are diagnostic and differ from those of classical Niemann-Pick disease.  相似文献   
28.
29.
Elbow fat pad sign: implications for clinical management.   总被引:3,自引:0,他引:3  
The significance of the radiological fat pad sign indicating elbow joint effusion after trauma when a fracture is not visible remains controversial. This retrospective analysis of 45 cases examines the need for routine repeat radiography at 2-week review. At follow-up, 29 had normal repeat radiographs, two had undisplaced radial head fractures, three had no radiographs but were clinically well and 11 failed to attend. The incidence of fracture in those having repeat radiography was 6%. We conclude that routine repeat radiography is unnecessary.  相似文献   
30.
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