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排序方式: 共有678条查询结果,搜索用时 62 毫秒
91.
92.
A non-invasive technique for measurement of cervical vertebral angle: report of a preliminary study 总被引:2,自引:0,他引:2
Martin Descarreaux Jean-Sébastien Blouin Normand Teasdale 《European spine journal》2003,12(3):314-319
Non-invasive methods have traditionally been used to assess spine positioning and range of motion. Recently, the use of prediction models derived from external stick markers and videographic analysis has been shown to be effective at predicting lumbosacral and segmental lumbar vertebral angles. The objective of this study was to develop a similar non-invasive method to predict cervical vertebral inclination in forward head flexion. Fourteen subjects with no history of trauma or inflammatory or arthritic disorders (mean age: 25+/-1 years) participated in this study on a voluntary basis. Radiographic and videographic measurements of four external markers (C0, C2, C6, C7) were taken for each subject at three different static head positions (neutral, and 30 degrees and 60 degrees of flexion). The data obtained from nine subjects with normal cervical configuration (lordosis) were used to develop statistical models predicting the radiographic segmental angles (dependent variables) from external markers (independent variables). A multiple regression model was developed for each vertebra (C1 to C6). These regression models predict the inclination of each cervical vertebra at three different neck angles with positional data derived from the four external skin markers. Adjusted R2 values of 0.97, 0.93, 0.93, 0.96, 0.95 and 0.89 were obtained for C1, C2, C3, C4, C5 and C6, respectively. The prediction models developed in this study can explain a large part of the variance for the relative contribution of each vertebral segment to global neck flexion and provide a greater accuracy then using external stick markers only. These models were not able to adequately predict the vertebral angular positioning of subjects presenting a cervical alordosis or kyphosis. 相似文献
93.
Dr. Edgardo L. Pérez M.D. M.P.H. Dr. Marvin Silverman M.D. Dr. Jane Blouin Ph.D. 《The Psychiatric quarterly》1985,57(1):18-22
The elderly (65 years or older) constitute approximately 25% of the patients referred for psychiatric consultations in general hospitals. The authors compared the clinical characteristics of and treatment recommendations for elderly and younger (less than 65 years) patients. Our findings revealed fourteen distinctive characteristics which differentiated the elderly from the younger patients. Most notably, the elderly have had a longer hospitalization at the time of the request for a psychiatric consultation and had a higher prevalence of organic brain syndromes (O.B.S.). Some of the implications of these results are discussed with the view to planning psychiatric services for the elderly in general hospitals. 相似文献
94.
Subjects were placed alone in a room where purposeful oral activity such as eating, talking and smoking was not permitted, while activity such as pursing the lips sucking on cheeks, grimaces etc was measured by a specially designed electromyometer. This was done via electrodes attached to the peri-oral area and was recorded in a standardized fashion. In contrast to expectations, total resting activity in the obese did not differ significantly from that of normals. However, the two groups differ in that the time lapse prior to major peaking is significantly shorter in normals than in the obese. Analysis of patterns of both obese and normals suggests cyclic activity of approximately 120 min duration, and this was confirmed with a small group of ten obese subjects. The implications of these findings, in terms of previous work on oral cycles in the obese as well as implications for future research, are discussed. 相似文献
95.
Eccentric ballooning of the distal esophagus was observed radiographically in 11 of 23 patients (48%) who underwent Heller myotomy for achalasia. While, to the authors' knowledge, ballooning at the site of myotomy incision has not been described previously in the radiologic literature, it should be recognized as a normal and frequent postoperative finding. Radiologists should be aware of this finding so that it is not mistaken for postoperative abnormalities following esophagomyotomy or an epiphrenic diverticulum. 相似文献
96.
de la Fuente J Almazán C Blas-Machado U Naranjo V Mangold AJ Blouin EF Gortazar C Kocan KM 《Vaccine》2006,24(19):4082-4095
The gene that encodes the tick protective antigen, 4D8, was cloned from 10 species belonging to 6 genera, and the nucleotide and amino acid sequences were analyzed. 4D8 nucleotide and protein sequences were conserved among these tick species with identity/similarity between 65-98 and 60-98%, respectively. The function of 4D8 was characterized by RNA interference (RNAi) in five tick species. After the ticks were allowed to feed, degeneration of gut, salivary glands and reproductive tissues was observed, and tick survival, weight and oviposition were significantly reduced. 4D8 RNAi effected >90% reduction in oviposition in all tick species tested. Because of the critical role that 4D8 plays during tick feeding and oviposition, which ultimately results in the reduction of tick progeny, we proposed the generic name "subolesin" (Latin, suboles: offspring, progeny) for tick 4D8 proteins and subA for the subolesin-encoding gene. 相似文献
97.
BACKGROUND: Maternal hypotension is common after spinal anesthesia for cesarean delivery. There is wide variability in the incidence and severity of hypotension and in the response to treatment. The beta2 adrenoceptor (beta2AR) possesses several polymorphic sites. Codons 16 (Arg16Gly) and 27 (Glu27Gln) have been shown to affect desensitization of the receptor. The goal of this study was to determine whether genetic variants of the beta2AR alter incidence of hypotension or the amount of vasopressor treatment required during spinal anesthesia for cesarean delivery. METHODS: One hundred seventy healthy women undergoing elective cesarean delivery were studied. Spinal anesthesia was performed with 12 mg hyperbaric bupivacaine, 25 microg fentanyl, and 200 microg morphine. Hypotension was treated with ephedrine and/or phenylephrine intravenously, and beta2AR genotype at codons 16 and 27 was determined. Analysis of variance was used to compare variables between genotypes, with data expressed as mean +/- SD. RESULTS: Ephedrine or phenylephrine was used in more than 90% of patients, with no difference in the incidence of hypotension between beta2AR genotypes. However, there was a significant effect of genotype on the amount of vasopressor required. Gly16 homozygotes received significantly less ephedrine (18 +/- 14 mg) than Arg16 homozygotes (28 +/- 13 mg) and Arg16Gly heterozygotes (30 +/- 20 mg; P = 0.0005). Glu27 homozygotes required significantly less ephedrine than Gln 27 homozygotes (14 +/- 13 vs. 30 +/- 19 mg; P = 0.002). Gln27Glu heterozygotes received less ephedrine than Gln27 homozygotes (23 +/- 16 vs. 30 +/- 19 mg; P = 0.03). CONCLUSIONS: Glycine at position 16 and/or glutamate at position 27 of the beta2AR leads to lower vasopressor use for treatment of hypotension during spinal anesthesia. 相似文献
98.
Bruce A. Pappas David A.V. Peters Sonya K. Sobrian Art Blouin Barbara Drew 《Pharmacology, biochemistry, and behavior》1975,3(4):681-685
Newborn rats received 7 consecutive daily injections of 6-hydroxydopamine (6-OHDA) or guanethidine. Locomotor activity, measured at 3 day intervals, was differentially affected by these drugs, although neither drug eliminated a characteristic pattern of ontogeny of locomotor activity. Differing neurochemical effects were also observed. 6-OHDA decreased tyrosine hydroxylase activity in cortex and cerebellum, increased it in the brainstem and had no effect on the hypothalamus. Guanethidine slightly elevated enzyme levels in all four brain regions, with the elevation in brainstem significant at 16 days of age. Regional brain changes in enzyme activity after 4 daily 6-OHDA injections beginning at 1, 5 or 9 days of age indicated that toxic effect of 6-OHDA upon catecholaminergic neurons was age dependent. These data are not consistent with a simple interpretation either in terms of maturational changes in blood brain barrier permeability to 6-OHDA or neuronal uptake of the drug. Further analyses of brainstem areas indicated that the increased brainstem enzyme activity after 6-OHDA was restricted to the pons. 相似文献
99.
Pharmaceutical Research - 相似文献
100.
Alain Veilleux Karine Blouin Caroline Rhéaume André Marette 《Metabolism: clinical and experimental》2009,58(5):624-631
Insulin receptor substrate-1 (IRS-1) and glucose transporter 4 (GLUT4) expression may provide an indirect reflection of the capacity of adipocytes to respond to insulin stimulation. We examined messenger RNA (mRNA) expression of these genes in omental and subcutaneous adipose tissue of women. Paired omental and subcutaneous adipose tissue samples were obtained from 36 women (age, 47 ± 5 years; body mass index, 28.0 ± 5.4 kg/m2) undergoing gynecologic surgeries. Total adiposity and visceral adiposity were assessed by dual-energy x-ray absorptiometry and computed tomography. The GLUT4 and IRS-1 mRNA expression levels were both significantly higher in subcutaneous compared with omental adipose tissue. A negative correlation was observed between body fat percentage and subcutaneous adipose tissue GLUT4 (r = −0.39, P < .05) and IRS-1 (r = −0.30, P < .08) mRNA abundance. However, in omental fat, only GLUT4 mRNA was inversely associated with body fat percentage (r = −0.53, P < .001). Moreover, the homeostasis model assessment of insulin resistance index was associated with mRNA expression of subcutaneous GLUT4 (r = −0.56, P < .001), subcutaneous IRS-1 (r = −0.51, P < .01), and omental GLUT4 (r = −0.54, P < .001), but not omental IRS-1. Interestingly, plasma adiponectin was only associated with subcutaneous GLUT4 (r = 0.48, P < .01) and IRS-1 (r = 0.48, P < .05) mRNA expression. The GLUT4 protein, unlike mRNA expression, was higher in omental than in subcutaneous adipose tissue. However, abdominal obesity-related differences in protein or mRNA expression were similar. Omental IRS-1 expression was low and unaffected by visceral obesity. In contrast, omental and subcutaneous GLUT4 as well as subcutaneous IRS-1 were reduced in visceral obesity. This divergent pattern of expression may reflect a lower capacity of omental adipose tissue to respond to insulin stimulation at all adiposity levels. 相似文献