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51.
To determine whether there are characteristic changes in event-related potentials (ERPs) in parkinsonian syndromes we studied 8 patients with progressive supranuclear palsy (PSP), 10 patients with corticobasal degeneration (CBD), 9 patients with striatonigral degeneration (SND), and 16 patients with idiopathic Parkinson's disease (PD) with a mean duration of illness shorter than 5 years in each group. A visual oddball paradigm was employed to elicit P300. P300 to the rare target and rare nontarget stimuli and reaction time (RT) to rare target stimuli in each group were compared with those in the corresponding age-matched normal control group and to each other after age correction. The correlation of P300 and RT to motor disability score was also studied. In PSP P300 amplitude was markedly reduced while in CBD P300 latency was prolonged. P300 amplitude to rare nontargets in SND and PD was attenuated. The mean RT in the PSP and the CBD group was significantly longer than in the other two groups. The mean RT in PD and P300 amplitude to rare nontargets in both CBD and PD showed significant correlation with the severity of motor disability. Simultaneous measurement of P300 and RT may yield useful supplementary information in facilitating diagnosis of parkinsonian syndromes in addition to clinical criteria. Received: 6 April 1999, Received in revised form: 5 August 1999, Accepted: 12 January 2000  相似文献   
52.
目的对在昆明市厂矿企业实施职业健康促进提出针对性建议。方法综合分析昆明市20个厂矿企业的1432名职工进行健康促进现况调查的结果。结果开展职业健康促进,提高职工整体健康水平必须采取综合干预措施,包括(1)加强领导,加强社区行动;(2)制定健康的公共政策,强化考核;(3)采取多种形式,提高职工自我保健技能;(4)创造支持性环境,维护职工身体健康。结论完善的企业健康促进方案有利于提高职工的健康水平,并可以为今后健康教育的实施、监测和效果评价奠定基础。  相似文献   
53.
细菌对MLS类和糖肽类抗生素产生耐药性的作用机制   总被引:3,自引:0,他引:3  
MLS类和糖肽类抗生素在人类与细菌感染性疾病的对抗中发挥着重要作用.与其他抗生素一样,随着这些抗生素的临床使用,细菌耐药性的出现和不断发展给人们带来新的挑战.本综述对这两类抗生素的细菌耐药性产生机制进行了剖析,并就已开发的若干个新型MLS类和糖肽类抗生素作了介绍.  相似文献   
54.
ObjectiveTo describe an arthroscopic technique for giant meniscal cyst excision with preservation of the functional meniscus, report the short‐ and medium‐term outcomes, and assess magnetic resonance imaging (MRI) for follow‐up imaging evaluations.MethodsA total of 54 consecutive patients with symptomatic meniscal cysts were admitted to the Second Xiangya Hospital of Central South University between 2014 and 2019. Nine patients with giant meniscus cysts (six females and three males) were included in this study. The age range of the patients was 6–34 years. All patients underwent a complete physical examination, X‐ray, Doppler ultrasound, and MRI of the knee preoperatively. After an arthroscopic diagnosis of a meniscal rupture with a giant meniscal cyst, partial meniscectomy, ablation of the cyst, and suturing of the retainable meniscus were performed. Lysholm and International Knee Documentation Committee (IKDC) scores were used preoperatively and at the most recent follow‐up. Clinical outcomes were classified into four categories: excellent, good, fair, and poor. During the last visit, all patients underwent MRI to assess the recurrence of the cyst and meniscal suture healing.ResultsPreoperative MRI and arthroscopic examination revealed giant meniscal cysts combined with meniscal tears and congenital discoid meniscus, and all giant meniscal cysts occurred in the lateral meniscus. The main types of meniscal tears were horizontal and complex tears. The cysts were unicystic in one case and multicystic in eight cases. The mean size of the cysts on the MRI was 5.86 cm × 2.24 cm × 2.48 cm. The mean follow‐up periods were 37.5 (19–60) months. Clinical outcomes were excellent in six patients and good in three patients. The postoperative scores were significantly improved compared to the preoperative scores (Lysholm: 90.78 ± 4.60 vs. 54.56 ± 7.25; IKDC: 96.2 ± 3.46 vs. 61.69 ± 3.36; p <0.01). No recurrence of the cyst was indicated on the MRI, and there was good healing of the torn meniscus.ConclusionsArthroscopic cystectomy combined with the meniscus suture technique was effective to eradicate residual cyst cavities, and traffic orifices be highly recommended.  相似文献   
55.
Hydration of fat-free mass (FFM), defined as the ratio of total body water (TBW) to FFM (TBW/FFM), is stable at 0.739 in adult mammals. However, an increase in the TBW/FFM ratio is common in hemodialysis (HD) patients. This study aimed to evaluate the determinants of TBW/FFM and investigate its predictive value for the prognosis of all-cause mortality in HD patients.We enrolled patients undergoing maintenance HD between July 2020 and May 2021. All patients were prospectively followed until death, HD dropout, or until the end of the study (November 1, 2021). A forward stepwise multivariable linear regression analyses was performed to test the independent relationship between TBW/FMM and other clinical variables. Receiver operating characteristic (ROC) analysis was used to discriminate the TBW/FFM with respect to 180-day mortality.Of the 106 patients, 42 had elevated TBW/FFM levels. Multiple linear regression analysis revealed that the TBW/FFM ratio was significantly associated with extracellular water (ECW)/TBW (standardized regression coefficient [β = 1.131, P < .001], phase angle (PhA) [β = 0.453, P < .001], and sex (β = 0.440, P < .001). We calculated the ROC curve (AUC) of TBW/FFM, ECW, ECW/TBW, and intracellular water (ICW) to compare the discriminatory capacities of these parameters in predicting 180-day mortality. The AUC for TBW/FFM (AUC = 0.849; 95% CI, 0.745–0.953) exhibited better discriminatory potential than ECW (AUC = 0.562; 0.410–0.714), although it had a similar predictive potential as the ECW/TBW ratio (AUC = 0.831; 0.731–0.932). High TBW/FFM can be used as a valuable prognostic index for predicting all-cause mortality in patients on HD.  相似文献   
56.
57.
BackgroundThere is increasing attention on the association of socioeconomic status and individual behaviors (SES/IB) with mental health. However, the impacts of SES/IB on mental disorders are still unclear. To provide evidence for establishing feasible strategies on disease screening and prevention, we implemented Mendelian randomization (MR) design to appraise causality between SES/IB and mental disorders.MethodsWe conducted a two-sample MR study to assess the causal effects of SES and IB (dietary habits, habitual physical activity, smoking behaviors, drinking behaviors, sleeping behaviors, leisure sedentary behaviors, risky behaviors, and reproductive behaviors) on three mental disorders, including bipolar disorder, major depressive disorder and schizophrenia. A series of filtering steps were taken to select eligible genetic instruments robustly associated with each of the traits. Inverse variance weighted was used for primary analysis, with alternative MR methods including MR-Egger, weighted median, and weighted mode estimate. Complementary methods were further used to detect pleiotropic bias.ResultsAfter Bonferroni correction and rigorous quality control, we identified that SES (educational attainment), smoking behaviors (smoking initiation, number of cigarettes per day), risky behaviors (adventurousness, number of sexual partners, automobile speeding propensity) and reproductive behavior (age at first birth) were causally associated with at least one of the mental disorders.ConclusionsMR study provides robust evidence that SES/IB play broad impacts on mental disorders.  相似文献   
58.
中药方剂防治骨质疏松症的研究概况   总被引:1,自引:5,他引:1  
中药方剂具有疗效好、副作用小、作用全面、适合长期服用等优势,已广泛应用于骨质疏松的防治。经典方来源于古代医书记载,疗效确切,临床上通过辨证施治,可随证对处方进行加减化裁;经验方来源于医师多年临床经验,处方组成相对固定,各自具有自身的特点,适用于特定证候类型的骨质疏松症;中成药的处方、剂型固定,服用方便,可单独使用,或与化学药物配伍使用。中药方剂防治骨质疏松症具有独特的优势,但尚有许多不足,应从整体、器官、组织、细胞和分子水平上系统研究其作用机制和特点。  相似文献   
59.
不同树龄三种厚朴中厚朴酚与和厚朴酚含量的研究   总被引:13,自引:4,他引:13  
在依据树皮年轮鉴定厚朴年龄的基础上,应用高效薄层扫描法,对不同生长年限的厚朴、凹叶厚朴、大叶木兰中所含厚朴酚、和厚朴酚的动态分布进行了含量测定,为道地药材的质量评价及合理采收提供了参考。  相似文献   
60.
南方红豆杉化学成分的研究进展   总被引:3,自引:0,他引:3  
李存芳  刘勇  董玫  史清文 《中草药》2007,38(8):1121-1132
南方红豆杉是我国的特有植物,在我国自然生长的5种红豆杉中分布最广,蕴藏量也最大,其化学成分研究在我国展开得最早,研究的时间最长也最彻底,到目前为止已经从我国南方红豆杉的根、茎、叶、皮、种子等不同部位中分离鉴定出147种化合物,包括二环紫杉烷类、各种三环紫杉烷类、松香烷类、9(10→20)重排的松香烷类和海松烷类二萜,以及木脂素类、黄酮类和酚类化合物。现总结过去20年南方红豆杉在化学成分方面的研究概况。  相似文献   
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