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101.
Non-invasive trigeminal evoked potentials: normative aging data 总被引:1,自引:0,他引:1
J Polich DJ Dalessio M Aung M DeYarman 《Cephalalgia : an international journal of headache》1995,15(2):147-151
A mild electric shock applied to the lower lip was used to elicit reliable evoked potentials from the trigeminal nerve in 50 normal adults who ranged in age from 20 to 69 years. The waveforms were morphologically similar to those observed with invasive procedures. No substantial effects for subject age, side of stimulation, or recording electrode were obtained for any of the individual trigeminal evoked potential amplitudes or latencies. Female subjects tended to have somewhat larger amplitudes and shorter latencies than male subjects. The results suggest that non-invasive procedures produce reliable evoked potential measures of trigeminal nerve function for patients of all ages. 相似文献
102.
JJ Korelitz ; AE Williams ; MP Busch ; TF Zuck ; HE Ownby ; LJ Matijas ; DJ Wright 《Transfusion》1994,34(10):870-876
BACKGROUND: Most blood centers utilize a confidential unit exclusion (CUE) process, intended to reduce the risk of transfusion-associated infectious diseases by allowing high-risk donors confidentially to exclude their blood from use for transfusion. The effectiveness of this method remains controversial. STUDY DESIGN AND METHODS: Confirmatory or supplemental test results for antibodies to human immunodeficiency virus, human T-lymphotropic virus type I, and hepatitis C virus, as well as hepatitis B surface antigen and syphilis and screening test results for antibodies to hepatitis B core (antigen) and alanine aminotransferase levels were obtained for approximately 1.8 million units donated during 1991 and 1992 at five blood centers within the United States. The prevalences of these infectious disease markers in units that the donors confidentially excluded (CUE+) and units that the donors did not exclude (CUE-) were calculated and examined within demographic subgroups. RESULTS: Units that were CUE+ were 8 to 41 times more likely to be seropositive for antibodies to human immunodeficiency virus and hepatitis C virus, hepatitis B surface antigen, and syphilis and three to four times more likely to react for antibody to hepatitis B core (antigen) or to have elevated alanine aminotransferase levels than units that were CUE- (p < 0.001). The positive predictive value of CUE (the percentage of CUE+ units that were confirmed seropositive for any marker) was 3.5 percent, and the sensitivity of CUE (the percentage of confirmed-seropositive units that were CUE+) was 2.3 percent. CONCLUSION: The current CUE process has low sensitivity and apparently low positive predictive value, and in many cases, it appeared that donors misunderstood it. Yet, CUE was not a “random process,” as CUE+ units were more likely to be seropositive for any infectious disease marker than CUE- units. This suggests that efforts to improve the CUE system may be warranted. As risk factors for transfusion-transmitted infection become more difficult to identify by history-based screening, however, such efforts may have limited effect. 相似文献
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Electrical stimulation of the cerebellar fastigial nucleus (FN) elevates regional cerebral blood flow (rCBF) independently of cerebral metabolism (rCGU) throughout brain. One hour of FN stimulation also reduces, by up to 50%, the volume of the focal ischemic infarction produced by occlusion of the middle cerebral artery in rat. Protected areas correspond to the ischemic penumbra. Neuroprotection, while reversible, persists for weeks after 1h of stimulation. It cannot be attributed to increasing rCBF and/or reducing rCGU to improve matching of flow and metabolism. Conditional stimulation of FN initiates long-lived inhibition of expression of peri-infarction depolarizing waves, possibly by altering potassium-channel function and suppresses induction of inducible nitric oxide synthase (iNOS) and ICAM in cerebral microvessels. The brain contains intrinsic networks which may protect the brain from ischemic injury, possibly by producing widespread and longterm suppression of electrical excitability and/or and expression of proinflammatory molecules. 相似文献
105.
Grace C. Kunas William Probasco Amgad M. Haleem Jayme C. Burket Emilie R.C. Williamson Scott J. Ellis 《Foot and Ankle Surgery》2018,24(6):495-500
Background
The aim of this study was to assess the inferior talus-superior talus (inf-tal-sup-tal) angle (previously proven reliable in multiplanar-weight bearing imaging (MP-WB)) on both computed tomography (CT) and MP-WB scans. We sought to compare the angle between the two modalities in both AAFD and control groups, as well as to compare the groups to each other.Methods
Inf-tal-sup-tal angles were compared between a stage II AAFD group (n = 38) with routine MP-WB and CT scans and a control group (n = 20) with preoperative CT scans for lisfranc injuries and normal hindfoot alignment after healing.Results
The CT inf-tal-sup-tal angle was significantly greater in AAFD compared to control (AAFD, 12 ± 6; control, 5 ± 4; p < 0.001), but was even greater with MP-WB. There was no significant correlation between inf-tal-sup-tal angles on MP-WB and CT (Pearson’s = 0.29, p = 0.08).Conclusions
MP-WB imaging proved to be correlated more strongly with AAFD than CT by revealing greater hindfoot valgus. This confirmed that CT scans are useful in predicting AAFD, but cannot be used as a surrogate for MP-WB scans. 相似文献106.
DJ Brown 《Transfusion》1988,28(1):21-23
Red cells from patients with sickle cell disease (HbSS and HbSC) are more resistant to lysis in hypotonic NaCl solutions than normal (HbAA) red cells. Taking advantage of this inherent resistance to osmotic stress, patient red cells (HbSS or HbSC) were rapidly isolated from donor red cells (HbAA or HbAS) by washing with hypotonic (0.3%) NaCl. The hypotonic method of washing provides a previously unavailable means for obtaining autologous HbSS or HbSC red cells from samples containing transfused donor red cells. Once isolated, these red cells can be used for phenotyping, autoadsorption, or evaluation of positive direct antiglobulin tests. 相似文献
107.
Use of the retroperitoneal approach has been well documented and used for intrapelvic cemented components or cement masses. We report on a single stage revision hip arthroplasty that incorporates a retroperitoneal approach for safe removal of an extensively entrapped porous-coated acetabular component and modular femoral head followed by an immediate reconstruction using a triflange acetabular prosthesis via a posterior approach. 相似文献
108.
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110.
NJ Liptrott M Penny PG Bray J Sathish SH Khoo DJ Back A Owen 《British journal of pharmacology》2009,156(3):497-508