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31.
Anuradha Ganesan Lorie Benning Elizabeth T Golub Mark Riddle Nancy Crum-Cianflone Sybil Tasker Lisa Jacobson Stephen J Gange 《AIDS research and therapy》2009,6(1):13-7
Background
Antiretrovirals used to treat HIV-infected patients have the potential to adversely affect serum lipid profiles and increase the risk of cardiovascular disease which is an emerging concern among HIV-infected patients. Since boosted atazanavir and efavirenz are both considered preferred antiretrovirals a head to head comparison of their effects on serum lipids is needed. 相似文献32.
希—内学习能力测验在中国聋儿中使用的信度和效度 总被引:4,自引:0,他引:4
采用经部分修改的希-内学习能力测验(H-NTLA)量表对全国21个省、市、自治区1758名3-17岁聋儿逐人测试。样本人群地区分布、家长职业构成与1990年全国人口普查资料一致。1758名聋儿智商呈现正态分布(g1=0.011P>0.05,g2=0.058P>0.05)。测试员间信度系数0.981(N=24),复测信度0.841(N=136),分半信度0.927(3-8岁)及0.854(9-17岁)。各分测验得分随年龄增加而增加,小年龄组增加明显,大年龄组增加缓慢。各分测验之间、各分测验和总离差智商之间大多数相关系数有显著统计学意义。智商与学习成绩(语文及数学)相关系数0.208(P<0.01N=224),与教师评语等级相关系数0.44(P<0.05df=16),表明经修订的H-NTLA量表适用于中国听力语言障碍人群进行智力评定。 相似文献
33.
Synergy between the genes for butyrylcholinesterase K variant and apolipoprotein E4 in late-onset confirmed Alzheimer's disease 总被引:5,自引:2,他引:5
The allelic frequency of the gene for the K variant of
butyrylcholinesterase (BCHE-K) was 0.17 in 74 subjects with late-onset (age
> 65 years) histopathologically diagnosed Alzheimer's disease (AD),
which was higher than the frequencies in 104 elderly control subjects
(0.09), in 14 early-onset cases of confirmed AD (0.07) and in 29 confirmed
cases of other dementia (0.10). The association of BCHE-K with late-onset
AD was limited to carriers of the epsilon 4 allele of the apolipoprotein E
gene (APOE), among whom the presence of BCHE-K gave an odds ratio of
confirmed late-onset AD of 6.9 (95% C.I. 1.65-29) in subjects > 65 years
and of 12.8 (1.9-86) in subjects > 75 years. In APOE epsilon 4 carriers
over 75 years, only 1/22 controls, compared with 10/24 confirmed late-onset
AD cases, had BCHE-K. We suggest that BCHE-K, or a nearby gene on
chromosome 3, acts in synergy with APOE epsilon 4 as a susceptibility gene
for late-onset AD.
相似文献
34.
35.
Identification and characterization of neurons with tremor-frequency activity in human globus pallidus 总被引:7,自引:0,他引:7
W. D. Hutchison A. M. Lozano R. R. Tasker A. E. Lang J. O. Dostrovsky 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》1997,113(3):557-563
Many previous studies have demonstrated the existence of neurons with tremor-frequency activity (”tremor cells”) in the thalamus
of Parkinson’s disease (PD) patients and these neurons are presumed to play a role in the pathogenesis of tremor. Since a
major input to motor thalamus (Voa and Vop) is from the internal segment of the globus pallidus (GPi), neurons with tremor-frequency
activity in motor thalamus may receive input from neurons in GPi. The aim of this study was to quantify the characteristics
of tremor cells in human globus pallidus. In three PD patients with tremor undergoing microelectrode exploration of the globus
pallidus prior to pallidotomy, 228 neurons were sampled, and 28 (12.3%) were identified to fire at the same frequency as the
tremor. These ”tremor cells” were located in the ventral portion of GPi. Autocorrelogram analysis of the sampled spike trains
of these 28 tremor cells was carried out over sequential 10-s time segments, and autocorrelograms showing maximal oscillatory
activity were graded from 0 to 10. Average tremor cell oscillation grades ranged from 6.8 to 7.8, similar to those reported
in the MPTP-induced primate model of parkinsonism. The average tremor cell oscillation grade varied between patients, as did
the clinical measures of tremor severity. Tremor cells had oscillations in spike discharges at the same average frequency
(4.2–5.2 Hz) as the patient’s tremor determined from the electromyogram and accelerometry records of one or more limbs (4.0–5.4
Hz), and the individual values were correlated (r
2=0.73) over the total range (3.7–5.6 Hz). The results of this study demonstrate the presence of neurons with 4–6 Hz tremor-frequency
activity in GPi, supporting a role of the globus pallidus in the production of rest tremor in PD patients.
Received: 27 February 1996 / Accepted: 18 October 1996 相似文献
36.
Ho AD; Grossman M; Trumper L; Pezzutto A; Pralle H; Boedewadt-Radzun S; Papendick U; God B; Zwingers T; Hunstein W 《Blood》1990,75(5):1119-1124
Plasma levels of soluble T-suppressor/cytotoxic antigen (sCD8) were measured at diagnosis or before systemic treatment in 69 patients with hairy cell leukemia (HCL). The 49 nonsplenectomized patients were characterized by high concentrations of sCD8 antigen as compared with 17 controls (P less than .0001). The median sCD8 level in non- splenectomized patients was 1,050 U/mL (range: 160 to 2,400 U/mL) and was significantly higher (P less than .0001) than the median of 275 U/mL (range: 20 to 1,080 U/mL) in splenectomized patients. The relationship of sCD8 to clinical response to subsequent interferon alpha (IFN alpha) treatment was analyzed. Patients who showed subsequent hematologic response with normalization of all blood counts had significantly lower levels of sCD8 concentrations at diagnosis than those who did not (P = .0056). Furthermore, normalization of sCD8 during IFN alpha treatment paralleled the achievement of normal counts in peripheral blood, whereas soluble interleukin-2 receptor (sIL-2R) levels remained high in most patients after 12 to 15 months of treatment. We speculate that activation of suppressor/cytotoxic T cells might play a role in myelosuppression, and its modulation during treatment with IFN alpha correlates with normalization in peripheral blood counts. 相似文献
37.
Jeffrey G. Tasker Masha Prager‐Khoutorsky Ryoichi Teruyama Jos R. Lemos William E. Amstrong 《Journal of neuroendocrinology》2020,32(4)
Hypothalamic magnocellular neuroendocrine cells have unique electrical properties and a remarkable capacity for morphological and synaptic plasticity. Their large somatic size, their relatively uniform and dense clustering in the supraoptic and paraventricular nuclei, and their large axon terminals in the neurohypophysis make them an attractive target for direct electrophysiological interrogation. Here, we provide a brief review of significant recent findings in the neuroplasticity and neurophysiological properties of these neurones that were presented at the symposium “Electrophysiology of Magnocellular Neurons” during the 13th World Congress on Neurohypophysial Hormones in Ein Gedi, Israel in April 2019. Magnocellular vasopressin (VP) neurones respond directly to hypertonic stimulation with membrane depolarisation, which is triggered by cell shrinkage‐induced opening of an N‐terminal‐truncated variant of transient receptor potential vanilloid type‐1 (TRPV1) channels. New findings indicate that this mechanotransduction depends on actin and microtubule cytoskeletal networks, and that direct coupling of the TRPV1 channels to microtubules is responsible for mechanical gating of the channels. Vasopressin neurones also respond to osmostimulation by activation of epithelial Na+ channels (ENaC). It was shown recently that changes in ENaC activity modulate magnocellular neurone basal firing by generating tonic changes in membrane potential. Both oxytocin and VP neurones also undergo robust excitatory synapse plasticity during chronic osmotic stimulation. Recent findings indicate that new glutamate synapses induced during chronic salt loading express highly labile Ca2+‐permeable GluA1 receptors requiring continuous dendritic protein synthesis for synapse maintenance. Finally, recordings from the uniquely tractable neurohypophysial terminals recently revealed an unexpected property of activity‐dependent neuropeptide release. A significant fraction of the voltage‐dependent neurohypophysial neurosecretion was found to be independent of Ca2+ influx through voltage‐gated Ca2+ channels. Together, these findings provide a snapshot of significant new advances in the electrophysiological signalling mechanisms and neuroplasticity of the hypothalamic‐neurohypophysial system, a system that continues to make important contributions to the field of neurophysiology. 相似文献
38.
Kees J.M. Lips Jaap Van Der Sluys Veer Albert Struyvenberg AD Alleman John R. Leo Paul Wittebol Werner H. Minder Cornelis J. Kooiker Rolf A. Geerdink Paul F.G.M. Van Waes Wil H.L. Hackeng 《The American journal of medicine》1981,70(5):1051-1060
Two kindreds with the multiple endocrine neoplasia type 2A syndrome were studied. Of one of these we examined 150 members, 20 of whom were treated with thyroidectomy for medullary carcinoma and nine with bilateral adrenalectomy for pheochromocytoma. Of the second kindred 59 members were examined, seven of whom were thyroidectomized and seven treated with bilateral adrenalectomy. Pheochromocytomas were invariably found on both sides, even in four cases in which the adrenals on one side appeared to be completely normal, not only at preoperative roentgenologic examination but also on inspection during the operation. The microscopic finding of micronodules and a cluster of abnormal medullary cells identical with those found in pheochromocytomas in one of the apparently normal adrenals represents a first stage in the development of diffuse medullary hyperplasia as well as nodular hyperplasia. This is in accordance with the fact that in the MEN type 2A syndrome pheochromocytomas are always multicentric and multiple in origin. On the basis of these findings we conclude that all patients with the MEN 2A syndrome who show symptoms and signs of active pheochromocytoma should be subjected to bilateral adrenalectomy, even when one or both of the adrenals appear to be normal at roentgenologic investigation. 相似文献
39.
S Birkenfeld J Dreiher D Weitzman AD Cohen 《Journal of the European Academy of Dermatology and Venereology》2011,25(4):436-440
Background Previous reports have demonstrated contradicting results on the association between lichen planus and hepatitis. Objectives The aim of this study was to investigate the association between lichen planus and viral hepatitis. Methods Patients with lichen planus were compared with controls regarding the prevalence of viral hepatitis in a case‐control study using logistic multivariate regression models. The study was performed utilizing the medical database of Clalit Health Services. Results The study included 1557 lichen planus patients over the age of 20 years and 3115 age‐ and gender‐matched controls. The prevalence of hepatitis C in patients with lichen planus was higher than that in the control group (1.9%, 0.4% respectively, P < 0.001). In a multivariate analysis, lichen planus was associated with hepatitis C (OR 4.19, 95% CI 2.21; 7.93). The prevalence of hepatitis B in patients with lichen planus was similar to that in the control group (0.9%, 0.5% respectively, P = 0.12). A multivariate analysis revealed that lichen planus was not associated with hepatitis B (OR 1.69, 95% CI 0.82; 3.47). Conclusion Lichen planus is associated with hepatitis C but not with hepatitis B. Physicians who care for patients with lichen planus should consider screening patients with lichen planus for hepatitis C. 相似文献
40.
A prospective evaluation of color flow mapping and real-time ultrasound was performed to determine if pseudoaneurysms could be distinguished from other causes of masses surrounding vascular grafts of the lower extremities. Twelve palpable pulsatile masses were imaged. Diagnoses were confirmed at angiography (n = 11), computed tomography (n = 7), aspiration biopsy (n = 5), and operative intervention (n = 6). A swirling pattern of blood flow was seen in six of seven cases of pseudoaneurysm. Lack of flow signals was noted in four of the five collections representing hematoma (n = 2) or infection (n = 2). The seventh case was later shown to be an infected, thrombosed pseudoaneurysm. The single false-positive diagnosis was made early in the series when the flow signals detected were due to transmitted arterial pulsations. The authors conclude that color Doppler flow imaging is useful in the differential diagnosis of pulsatile masses associated with prosthetic grafts. Prosthetic graft pseudoaneurysms have a specific appearance of swirling blood flow arising from a wide neck and are distinguishable from traumatic or iatrogenic pseudoaneurysms of the native vascular tree. 相似文献