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11.
Susan De Santi Ph.D. Mony J. de Leon Ed.D. Antonio Convit M.D. Chaim Tarshish M.S. Henry Rusinek Ph.D. Wai Hon Tsui M.S. Elia Sinaiko Ph.D. Gene-Jack Wang M.D. Elsa Bartlet Ph.D. Nora Volkow M.D. 《The Psychiatric quarterly》1995,66(4):357-370
While many neuropsychological studies have demonstrated age-related performance alterations in tests thought to reflect frontal and temporal lobe function, there is little direct observation and comparison of these hypothesized brain changesin vivo. The cerebral glucose metabolism of frontal, temporal, and cerebellar regions was examined in 40 young (
=27.5±4.9) and 31 elderly (
=67.6 ± 8.8) normal males using PET-FDG. Univariate analysis showed age-related metabolic reductions in all frontal and temporal lobe regions. The reductions ranged from 13%–24% with the greatest changes in the frontal lobes. Multiple regression analyses showed a stronger age relationship with frontal lobe than with temporal lobe metabolism. The dorsal lateral frontal lobe was the region that appears to change most within the frontal lobes. Examination of the temporal lobe showed that age contributed equally to the metabolic variance of both the lateral temporal lobe and hippocampus. These results suggest that age-related metabolic changes exist in both frontal and temporal lobes and that the frontal lobe change is greater. 相似文献
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Acute catatonic syndromes occurring in the context of various medical and neuropsychiatric conditions, including schizophrenia,
have been shown to respond well to benzodiazepines (BZD). However, there have been no studies specifically designed to address
the BZD treatment response of persistent catatonic states. Eighteen patients with clinically stable chronic schizophrenia,
who also displayed enduring catatonic features, underwent a 12-week long, random assignment, double-blind, placebo-controlled
cross-over trial with lorazepam (6 mg/day). A comprehensive assessment, including the subjects’ clinical and motor (catatonic
as well as drug-induced movement disorders) condition, was performed at baseline and four weekly intervals thereafter. Pre-existing
medication was kept constant throughout the study. Lorazepam had no effect on the subjects’catatonic signs and symptoms, suggesting
that acute and chronic catatonic syndromes associated with schizophrenic illness might have a different neurobiological basis.
Received: 25 May 1998/Final version: 22 September 1998 相似文献
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Anti‐fibrotic and Anti‐tumorigenic Effects of Rhein,a Natural Anthraquinone Derivative,in Mammalian Stellate and Carcinoma Cells 下载免费PDF全文
Anthraquinone compounds have been recognized to possess antiinflammatory, anti‐fibrotic and anti‐tumour properties and thus applied in human and veterinary therapeutics as active substances of medicinal products. Amongst the anthraquinones isolated from Rheum palmatum, also known as da‐huang, rhein was detected as one of the highest metabolite contents in the bloodstream of mammals. The biological activities of rhein therefore deserve detailed investigation. In this study, we aimed to delineate the mechanism of inhibitory actions of rhein on fibrotic and tumorigenic processes by means of various biochemical assays, such as immunofluorescent staining, real‐time polymerase chain reaction (PCR) and western blotting analyses in rat pancreatic stellate cells (LTC‐14), human pancreatic ductal adenocarcinoma cells (PANC‐1) and human colon carcinoma cells (SW480 and SW620). Our results demonstrated that the application of rhein notably suppressed the mRNA and protein levels of various fibrotic and tumorigenic mediators including alpha‐smooth muscle actin, type I collagen, fibronectin, N‐cadherin and matrix metalloproteinases in the testing mammalian cells. The mechanism of the suppressive actions of rhein was associated with the modulation of the sonic hedgehog and serine‐threonine kinase signalling pathways. In conclusion, we suggest that rhein may serve as a therapeutic or an adjuvant agent in anti‐fibrotic and anti‐tumorigenic approaches. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
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Aim of study
In this study, we have investigated the analgesic and anti-arthritic effects of a traditional Chinese medicine (TCM) combination of Lingzhi and San Miao San (SMS) in a rat model of arthritis induced by Freund's complete adjuvant (FCA).Materials and methods
Sprague–Dawley rats were induced with monoarthritis by single unilateral injection of FCA into the knee joint. The TCM combination was administered to the rats daily by intraperitoneal injection (50 mg/(kg day)) or via oral administration (500 mg/(kg day)) for 7 days before induction of arthritis and 7 days after. Extension angle that provoked struggling behavior, and size and blood flow of the rat knees were measured to give indexes of allodynia, edema, and hyperemia, respectively. The extent of cell infiltration, tissue proliferation, and erosions of joint cartilage provided additional indexes of the arthritis condition.Results
FCA injection produced significant allodynia, edema, hyperemia, immune cell infiltration, synovial tissue proliferation, and erosions of joint cartilage in the ipsilateral knees compared with the contralateral saline-injected knees. Intraperitoneal injection of the TCM combination (50 mg/(kg day)) suppressed allodynia, edema, and hyperemia in the inflamed knees, and oral administration (500 mg/(kg day)) suppressed edema and hyperemia. Histological examination showed that the TCM administered by either route reduced immune cell infiltration and erosion of joint cartilage.Conclusions
These findings suggest the Lingzhi and SMS formulation has analgesic and anti-inflammatory effects in arthritic rat knees, and concur to previous clinical studies that showed the TCM combination reduced pain in rheumatoid arthritis patients, and extends its possible benefit to suppression of inflammatory symptoms in these patients. 相似文献16.
OBJECTIVE: To evaluate expectation and knowledge on obstetric ultrasound examination in the first and second trimester in a Chinese population. METHOD: A cross-sectional survey was conducted in a university obstetric clinic in Hong Kong. Chinese pregnant women who underwent the first trimester early scan sessions, or the second trimester anomaly scan sessions were invited to complete a self-administered questionnaire, which contained items on their knowledge, expectation, and sociodemographic characteristics. RESULTS: In all 276 eligible pregnant women (117 in the first trimester and 159 in the second trimester) were recruited. Although 249 women (90.2%) claimed they understood the indication of the ultrasound examination, only 93 of them were correct (33.7%). The median perceived overall-detection rate for structural abnormalities was 66.5%. Living in Hong Kong for more than 7 years was significantly associated with higher knowledge level and expectation from ultrasound examination. Attaining tertiary education level was also significantly associated with higher knowledge level. Over 90% of the pregnant women studied wished to know the fetal gender from the anomaly scan examination. CONCLUSION: Knowledge of Chinese pregnant women on ultrasound was generally unsatisfactory. Understanding their limitation of knowledge and expectations helps to devise appropriate education in the local setting. 相似文献
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BACKGROUND: The role of laparoscopic cholecystectomy (LC) in acute cholecystitis remains controversial. The aim of the present study was to determine the incidence, clinicopathological characteristics, and outcome of patients with gallbladder cancer presenting with acute cholecystitis. METHODS: We performed a retrospective analysis of patients with gallbladder cancer who presented with acute cholecystitis and were treated at the public hospitals in Hong Kong between 1998 and 2002. RESULTS: Among 2,700 patients with acute cholecystitis managed with cholecystectomy (1,347 open and 1,353 LC), 63 patients (2.3%) were found to have gallbladder cancer. There were 44 women and 19 men with a mean age of 74.7 (+/-12.8) years. Adenocarcinoma (90.5%) was the most common cancer. The overall median survival was 5 months (95% CI = 2.6-7.4). The 5-year survival rate was 20.8%. Laparoscopic cholecystectomy was attempted in 11 patients and was completed successfully in six of them. There was no difference between the LC and open groups in the complication rate, hospital mortality rate, or survival rate. CONCLUSIONS: In the ethnic Chinese population of Hong Kong, the incidence of gallbladder cancer presenting with acute cholecystitis is higher than the same finding in patients undergoing elective cholecystectomy for cholelithiasis. Long-term survival is possible because such patients may be diagnosed at an early stage of the disease. 相似文献
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目的寻求制作门静脉高压动物模型的最佳方法,并以此为基础从事肝硬化后门静脉血液动力学基础研究。方法以3组共15只兔为动物模型,分别以0.2%、0.4%、0.8%浓度的白芨粉为栓塞材料,开腹注入兔门静脉内,手术前后行门静脉测压、血管造影及病理学检查,最长观察时间阎周.结果以0.4%浓度白芨粉制作门静脉高压模型最佳,4周后肝脏体积缩小20%,门静脉压平均升高40%,病理呈典型坏死后肝硬化表现。结论以白芨粉为栓塞材料制作肝硬化门静脉高压动物模型方法简单、效果可靠已重复性好.以不同浓度的白芨栓塞剂来控制坏死后肝纤维化的程度是本试验的一大特点,本动物模型的建立对深入研究肝硬化门静脉高压的成因及治疗措施有着重要意义。 相似文献