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91.
Magnetic resonance imaging for detecting lesions of multiple sclerosis: comparison with computed tomography and clinical assessment. 总被引:1,自引:0,他引:1
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Eighty-two patients with known or suspected multiple sclerosis (MS) were examined by means of magnetic resonance imaging (MRI) with a 0.15-T resistive scanner. The diagnosis could be made by MRI in 34 (97%) of the 35 patients with chronic, well-documented, stable MS and by high-volume delayed x-ray computed tomography (HVD CT) in only 6 (54%) of 11 patients in this group. The stage of the disease as judged from the MRI scans correlated poorly with the clinical status of the patient and with the known duration of the disease. MRI identified 28 (88%) of the 32 patients in whom MS was subsequently diagnosed by a neurologist, whereas regular contrast or HVD CT identified only 11 (52%) of 21 such patients. MRI is the most sensitive imaging modality for MS but is of little value in assessing the severity of the disease: many of the lesions seen on MRI scans are clinically "silent", and MRI does not usually detect small lesions in the brainstem, cerebellum or spinal cord that may be clinically significant. 相似文献
92.
This study examined the possibility that amphetamine-induced stereotypy and facilitation of memory consolidation are both mediated by amphetamine's stimulation of dopaminergic activity in the caudate nucleus. In the first experiment, rats were given pairings of a tone and a shock followed by SC amphetamine (2 mg/kg). The amount of stereotypy and increased locomotor activity produced by the injection were measured immediately. Retention of the tone-shock association was evaluated 48 h later by observing the ability of the tone to suppress drinking. The degree of retention was significantly correlated with the amount of stereotypy but not with the amount of locomotion previously measured. In the second experiment, amphetamine was microinjected into the caudate nucleus (10 g/l) and its ability to produce the same three behavioral effects was examined. These injections produced increased stereotypy and improved retention, but no increase in locomotion. The correlation of memory facilitation with stereotypy and the fact that both were produced by intracaudate amphetamine suggest that they may be mediated by the same neuropharmacological substrate, namely amphetamine-induced release of dopamine in the caudate. 相似文献
93.
Nguyen Tuyen Trat Tiffany Tieu Ngoc Thanh Vu Linda Sokal-Gutierrez Karen 《Maternal and child health journal》2022,26(9):1811-1819
Maternal and Child Health Journal - Vietnam’s post-war globalization, economic development, and urbanization have contributed to a nutrition transition from traditional diets to... 相似文献
94.
Kaixuan Che Junqiang Qiu Longyan Yi Menghui Zou Zhihui Li Amelia Carr Rhiannon M.J. Snipe Dan Benardot 《Nutrients》2021,13(3)
Periodized carbohydrate availability can enhance exercise capacity, but the effects of short-term fat adaptation carbohydrate restoration (FACR) diets on metabolic responses and exercise performance in endurance athletes have not been conclusively determined. This study aimed to investigate the effect of a FACR diet on measures of resting metabolism, exercise metabolism, and exercise performance. Well-trained male runners (n = 8) completed a FACR dietary intervention (five days’ carbohydrate < 20% and fat > 60% energy, plus one-day carbohydrate ≥ 70% energy), and a control high-carbohydrate (HCHO) diet for six days (carbohydrate > 60% energy; fat < 20% energy) in a randomized crossover design. Pre- and post-intervention metabolic measures included resting metabolic rate (RMR), respiratory quotient (RQ), maximum fat oxidation rate during exercise (MFO), and maximum fat oxidation intensity (FATmax). Measures of exercise performance included maximal oxygen uptake (VO2max), running economy (RE), and 5 km running time trial (5 km-TT). In FACR compared with HCHO, there were significant improvements in FATmax (p = 0.006) and RE (p = 0.048). There were no significant differences (p > 0.05) between FACR and HCHO in RMR, RQ, VO2max, or 5 km-TT. Findings suggest that a short-term (six days) FACR diet may facilitate increased fat oxidation and submaximal exercise economy but does not improve 5 km-TT performance. 相似文献
95.
Kim Han Komudi Singh Matthew J. Rodman Shahin Hassanzadeh Yvonne Baumer Rebecca D. Huffstutler Jinguo Chen Julin Candia Foo Cheung Katherine E. R. Stagliano Mehdi Pirooznia Tiffany M. Powell-Wiley Michael N. Sack 《Nutrients》2021,13(5)
Intermittent fasting and fasting mimetic diets ameliorate inflammation. Similarly, serum extracted from fasted healthy and asthmatic subjects’ blunt inflammation in vitro, implicating serum components in this immunomodulation. To identify the proteins orchestrating these effects, SOMAScan technology was employed to evaluate serum protein levels in healthy subjects following an overnight, 24-h fast and 3 h after refeeding. Partial least square discriminant analysis identified several serum proteins as potential candidates to confer feeding status immunomodulation. The characterization of recombinant IGFBP1 (elevated following 24 h of fasting) and PYY (elevated following refeeding) in primary human CD4+ T cells found that they blunted and induced immune activation, respectively. Furthermore, integrated univariate serum protein analysis compared to RNA-seq analysis from peripheral blood mononuclear cells identified the induction of IL1RL1 and MFGE8 levels in refeeding compared to the 24-h fasting in the same study. Subsequent quantitation of these candidate proteins in lean versus obese individuals identified an inverse regulation of serum levels in the fasted subjects compared to the obese subjects. In parallel, IL1RL1 and MFGE8 supplementation promoted increased CD4+ T responsiveness to T cell receptor activation. Together, these data show that caloric load-linked conditions evoke serological protein changes, which in turn confer biological effects on circulating CD4+ T cell immune responsiveness. 相似文献
96.
Beighley Adam Glynn Ryan Scullen Tyler Mathkour Mansour Werner Cassidy Berry John F. Carr Christopher Abou-Al-Shaar Hussam Aysenne Aimee Nerva John D. Dumont Aaron S. 《Neurosurgical review》2021,44(5):2511-2522
Neurosurgical Review - Aneurysmal subarachnoid hemorrhage (aSAH) is an emergent condition requiring rapid intervention and prolonged monitoring. There are few recommendations regarding the... 相似文献
97.
Background: There are several congenital hand differences that cause thumb-index (TI) web space deficiency. There is a knowledge gap in the literature about the hand differences that are associated with TI web space deficiency. We aimed to identify these congenital differences and the various specific reconstructive surgical procedures that are used for these conditions. Methods: We conducted a retrospective chart review of children treated operatively over a period of 30 years for congenital TI web space deficiency by the senior author (G.M.R.). We gathered data on demographics and associated congenital hand differences and compiled a list of all surgical procedures performed for the web space and the ipsilateral upper extremity. Results: We included 71 patients (77 hands) with 12 congenital hand differences (62 developmental and 9 spastic). The total number of upper extremity operations, (ie), anesthetics performed for these patients was 186, averaging 2.6 settings and 7.5 procedures for each patient. Cutaneous reconstructive procedures included first dorsal metacarpal artery pedicle flaps (49 patients), 4-flap Z-plasties (15), and transposition flaps (13). In addition, 16 different thumb reconstructive procedures were necessary. Ten patients required revision of their TI web space procedures for recurrence. Conclusions: The prevalence of TI web space deficiency is underappreciated. These patients often have multiple musculoskeletal anomalies of the hand and upper extremity that should be ruled out and require surgical treatment to optimize hand function. Consideration should be given to performing more than one procedure in one setting when possible. 相似文献
98.
Albright Christopher A. Kimball Devon Brady John P. Luna Issabella Brown Tiffany Calzo Jerel P. Pennesi Jamie-Lee Blashill Aaron J. 《Archives of sexual behavior》2022,51(5):2523-2533
Archives of Sexual Behavior - Sexual minority men (SMM) remain disproportionately burdened by sexually transmitted infections. Although gay community involvement has been theorized to be protective... 相似文献
99.
100.
Bruce R. Carr Michael A. Thomas Angelina Gangestad David L. Eisenberg Andrea Olariu Mitchell D. Creinin 《Contraception》2021,103(1):26-31
ObjectiveEvaluate reproductive function in nulligravid and gravid women after levonorgestrel 52 mg intrauterine system (IUS) discontinuation based on time to pregnancy.Study designWe evaluated women participating in the ACCESS IUS multicenter, Phase 3, open-label clinical trial of the Liletta(®) levonorgestrel 52 mg IUS who discontinued the IUS within 60 months of use and desired pregnancy. Study staff contacted participants every three months after IUS discontinuation for up to 12 months to determine whether pregnancy occurred. We excluded women who opted to stop attempting to conceive before 12 months. We evaluated 12-month conception rates in participants 16–35 years at IUS placement, comparing dichotomous outcomes using Fisher’s exact test. We performed a multivariable analysis to assess the association of baseline characteristics, age at discontinuation, duration of IUS use, and positive sexually transmitted infection testing during IUS use with conception.ResultsAmong 165 women who attempted to conceive, 142 (86.1%) did so within 12 months with a median time to conception of 92 days. The 12-month conception rates did not differ between nulligravid (66/76 [86.8%]) and gravid (76/89 [85.4%]) women (p = 0.83) and nulliparous (78/90 [86.7%]) and parous (64/75 [85.3%]) women (p = 0.83). In multivariable analysis, only obesity (aOR 0.3 [95% CI 0.1–0.8]) was associated with ability to conceive.ConclusionsAfter levonorgestrel 52 mg IUS discontinuation, women have rapid return of fertility in the year post-removal. Fertility rates after IUS removal do not vary based on gravidity, parity, age at discontinuation, or duration of IUS use.ImplicationsThis contemporary IUS study included a large population of nulligravid and nulliparous women. IUS use over many years does not effect spontaneous fertility after IUS discontinuation, regardless of gravidity or parity. Providers and patients should have no concern about the impact of IUS use on future fertility. 相似文献