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31.
Transluminal angioplasty of the vertebral and basilar artery 总被引:4,自引:0,他引:4
R T Higashida G B Hieshima F Y Tsai V V Halbach D Norman T H Newton 《AJNR. American journal of neuroradiology》1987,8(5):745-749
Transluminal angioplasty of brachiocephalic vessels for atherosclerotic lesions is now being performed in selected cases. We have thus far treated 17 cases of vertebral artery stenosis and one case of basilar artery stenosis by intravascular balloon dilatation techniques. Clinical presenting symptoms included vertebral basilar insufficiency, repeated transient ischemic attacks (TIAs), and multiple strokes. We performed successful transluminal angioplasty in 16 patients with marked narrowing (greater than 70%) of the dominant vertebral artery from atherosclerosis. One patient with basilar artery stenosis with tandem atherosclerotic lesions was also treated by angioplasty techniques. Repeat angiography at 3- to 12-month intervals has revealed continued patency at the angioplasty site. Complications occurred in our one patient with basilar artery angioplasty, who suffered a brainstem infarction after treatment, and in one patient who had a TIA after bilateral vertebral artery angioplasty. Two other patients had residual vertebral stenosis but remained asymptomatic after the procedure. All other patients who had successful dilatation were asymptomatic at 6 months to 2 years (mean, 15 months) of follow-up. These initial studies indicate that vertebral artery angioplasty may be effective for treating high-grade atherosclerotic lesions and for improving blood flow to the posterior circulation. Angioplasty of the basilar artery is technically more difficult and has a higher degree of risk because of the many perforating branches supplying the brainstem. 相似文献
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33.
Effect of blockade of TNF-alpha and interleukin-1 action on bone resorption in early postmenopausal women. 总被引:1,自引:0,他引:1
Natthinee Charatcharoenwitthaya Sundeep Khosla Elizabeth J Atkinson Louise K McCready B Lawrence Riggs 《Journal of bone and mineral research》2007,22(5):724-729
After acute estrogen withdrawal in postmenopausal women, administration of anakinra or etanercept, specific blockers of IL-1 and TNF-alpha, respectively, reduced the rise in bone resorption markers to about one half of that in controls. This is consistent with an important role for these immune cytokines in mediating the effect of estrogen deficiency on bone. INTRODUCTION: Studies in rodents have implicated increased production of interleukin (IL)-1 beta and TNF-alpha as mediators of bone loss after ovariectomy, but their roles are unclear in humans whose immune system differs markedly from that of rodents. MATERIALS AND METHODS: We administered transdermal estradiol, 0.1 mg/d, for 60 days to 42 early postmenopausal women. Estrogen treatment was discontinued, and subjects were randomly assigned to intervention groups receiving 3 wk of injections with 0.9% saline, anakinra 100 mg/d, or etanercept 25 mg/twice weekly. Bone turnover was assessed by measuring serum carboxyl-terminal telopeptide of type 1 collagen (CTX) and amino-terminal telopeptide of type 1 collagen (NTX), markers for bone resorption, and serum amino-terminal propeptide of type 1 collagen (P1NP), a marker for bone formation. Results were expressed as percent change in markers from baseline (last 2 days of estrogen treatment and days 20 and 21 of intervention). RESULTS: The percent changes from baseline during intervention for serum CTX, urine NTX, and serum PINP, respectively, were 43.3 +/- 8.0%, 12.0 +/- 7.1%, and -41.0 +/- 2.5% for the control group; 25.9 +/- 6.3%, 9.5 +/- 4.0%, and -37.8 +/- 3.0% for the anakinra group; and 21.7 +/- 5.0%, 0.32 +/- 3.82%, and -34.5 +/- 3.9% for the etanercept group. Compared with the control group, the blunting of the increase in serum CTX fell just below the level of significance (p=0.10) after anakinra treatment, whereas the blunting of the increase in serum CTX (p=0.034) and in urine NTX (p=0.048) were significant after etanercept treatment. Other changes were not significant. CONCLUSIONS: The data are consistent with a role for TNF-alpha, and possibly for IL-1 beta, in mediating increased bone resorption during estrogen deficiency in women. Although either cytokine blocker reduced serum CTX by about one half, the effect of combined blockade could not be tested because of concerns about toxicity. The data do not exclude direct or indirect contributory roles for RANKL or for other cytokines. 相似文献
34.
Neurological signs and symptoms are common in recreational divers with decompression illness (DCI). The spectrum of neurological manifestations, temporal profile, and laboratory findings are described in a large series of 200 consecutive recreational divers treated for DCI. The Hyperbaric Medicine Unit charts of 200 recreational divers treated for DCI were reviewed and analyzed. The cohort was mainly male, with a median age of 40 years, and quite experienced, with a median of 100 prior dives. In 44 divers (22%) a rapid ascent was documented. The median time to onset of neurological symptoms was 60 minutes after surfacing. One hundred seventy-seven of 200 divers (88.5%) had at least one symptom of neurological DCI at presentation. The most common neurological manifestations were paresthesia, dysesthesia, incoordination, motor weakness, and dizziness. Paresthesias were associated with significantly younger (p = 0.003) and less experienced (p = 0.03) divers. Similar but less significant correlations were noted for dysesthesias. Female divers were significantly more likely to experience painful skin symptoms (p < 0.001). Neurological manifestations are common in recreational divers treated for DCI. Neurological DCI and paresthesias are more likely to occur in younger and less experienced divers. 相似文献
35.
Victoria L. Herzberg 《Immunological investigations》1991,20(5):507-513
Serum, which is required for activation of T cells in vitro, was fractionated to isolate and identify major supportive components. The serum activity concentrated exclusively with the lipoprotein fractions LDL and HDL. Furthermore, oleic and linoleic acids were equally active supplements, suggesting that resting T cells may require exogenous lipid because they are incapable of synthesizing fatty acid. A survey of fatty acids disclosed that all were capable of some degree of support. Titration delineated the narrow concentration range of lipid supplements successful in supporting T cell proliferation and demonstrated that concentrations must be rigidly controlled to optimize cell proliferation. 相似文献
36.
Identifying environmental factors reflected to alcohol use is important for program planning and evaluation in college alcohol and drug prevention programs. Little has been written concerning uses of data in environmental prevention efforts. This paper presents four brief interrelated case studies of how environmental modifications were used by a college alcohol prevention project to 1) change the marketing practices and service policies of a student-oriented bar, 2) alter the sales practices of a campus bookstore concerning alcohol paraphernalia, 3) to develop a campaign with the goal of reducing risk factors related to heavy drinking at private student parties, and 4) stop an unsafe bus from transporting students to bars in Mexico. Creative use of such environmental prevention approaches has potential benefit to colleges and universities concerned with the primary prevention of alcohol-related problems experienced by students. 相似文献
37.
38.
Stroke rehabilitation is an area of practice that many occupational therapists encounter during their career. The literature promotes a wide range of management techniques and support devices for people who have a stroke-affected upper limb, but little is known about the validity of those that occupational therapists actually use in practice. A questionnaire was sent to occupational therapists working in Queensland and northern New South Wales facilities (n = 35), in which adults with a stroke were likely to be treated. Eighteen respondents answered questions about the management techniques and support devices used in their facility, and their perception of the benefit of these devices in the reduction of hemiplegic shoulder pain. Results are discussed with reference to evidence-based practice and indicate an urgent need for the collation and dissemination of the best current evidence available for the management techniques and support devices used in this area, as well as further research to extend this evidence. 相似文献
39.
Udeni B.R. Balasuriya Jessika C. Dobbe Victoria L. Smalley Eric J. Snijder 《Virology》2004,327(2):318-319
40.
Victoria L Morgan Benoit M Dawant Yong Li David R Pickens 《Computerized medical imaging and graphics》2007,31(6):436-446
The objectives of this study were to use computer-generated phantoms containing real subject motion to: (1) compare the sensitivity of four commonly used fMRI software packages and (2) compare the sensitivity of three statistical analysis strategies with respect to motion correction. The results suggest that all four packages perform similarly in fMRI statistical analysis with SPM2 having slightly higher sensitivity. The most sensitive analysis technique was to perform motion correction and include the realignment parameters as regressors in the general linear model. This approach applies to all four packages examined and can be most beneficial when stimulus-correlated motion is present. 相似文献