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121.
OBJECTIVE: To identify the structure of the alkaloid extract of Gelsemium from east Guangdong province of China. METHODS: Fourier transform infrared (FTIR) absorption spectrometry, hydrogen and carbon spectra of nuclear magnetic resonance (NMR) and distortionless enhancement by polarization transfer (DEPT) analysis were used for the structural identification of the alkaloid exstract of Gelsemium. RESULTS: The frequency, intensity and shape of the extract's characteristic peaks in infrared absorption spectra (4,000.0-400.0 cm(-1)) and (1)H NMR, (13)C NMR were recognized and compared. The molecular structure of the sample was consistent with the theoretically derived model. CONCLUSION: The extract is structurally identical to koumine, which may provide evidence for its safe clinical application and establishment of Chinese medicine fingerprint database of Gelsemium.  相似文献   
122.
This study evaluated the feasibility of reducing the indinavir (IDV) dosage in Taiwanese patients receiving the standard IDV/ritonavir (RTV) dosage of 800/100 mg twice a day who had undetectable plasma human immunodeficiency virus type 1 (HIV-1) RNA but had developed IDV-related toxicities. After dosage reduction to IDV/RTV 600/100 mg twice a day, the dose-related toxicity decreased and plasma HIV RNA remained undetectable at 24 weeks post-switch in all patients. The maximal plasma concentration (Cmax) and area under the plasma concentration-time curve of IDV decreased significantly (median, 6.3 vs 4.3 microg/mL and 1892 vs 1292 microg.min/mL, p=0.01 and 0.001, respectively) but the minimal plasma concentration remained at a similar level (median, 1.0 vs 0.8 microg/mL, p=0.12). This study found that the reduction in the dosage of IDV in HIV-1 infected patients receiving the standard IDV/RTV regimen guided by therapeutic drug monitoring decreased the Cmax, dose-related toxicity and medical cost without compromising viral control.  相似文献   
123.
目的 探讨急性胰腺炎与血浆维生素C、维生素E和 β 胡萝卜素的关系。 方法 采用分光光度比色分析法检测 6 8例急性胰腺炎和 4 0例健康献血员血浆三种维生素含量。结果 急性胰腺炎组维生素C、维生素E、β 胡萝卜素含量较对照组显著降低 (P <0 .0 1) ,且随着禁食时间的延长呈逐渐降低趋势。 结论 急性胰腺炎时患者体内的氧化和抗氧化系统平衡失调 ,补充抗氧化维生素有助于病情的恢复。  相似文献   
124.
BACKGROUND: The ubiquitin-proteasome system (UPS) is thought to be functionally active in atherosclerosis (AS) lesions. Aspirin was found to be a potent inhibitor of the UPS in some tumour studies; however, its effect on AS remains to be demonstrated in vivo. METHODS: New Zealand rabbits were placed on a normal diet (N) or on a normal diet with aspirin (NI) or on an atherogenic diet without (H) or with aspirin (HI) for 12 weeks. Proteasome activity, concentrations of plasma lipids and levels of peroxidation were determined. Ubiquitin/ubiquitin-conjugates (Ub), IkappaBalpha, phosphorylated IkappaB (pIkappaBalpha) and p65 were investigated by Western blotting or immunochemistry. RESULTS: Concentrations of plasma lipids and peroxidation levels were higher in H or HI vs. N or NI. Histological analysis showed that atheroma was increased in H. Ub and IkappaBalpha were mainly localised in subendothelium and media vascular smooth muscle cells. Western blots revealed that Ub, IkappaBalpha, and pIkappaBalpha were increased, whereas p65 was lower in HI vs. H. The activity of the 20S proteasome was functionally active in H vs. N, NI or HI, while the 26S proteasome was not affected in any of the groups. CONCLUSIONS: Aspirin can attenuate the pathogenesis of atheroma formation, the degradation of IkappaBalpha and pIkappaBalpha, and lower the expression of p65, indicating that its therapeutic effects on AS may be via inhibition of the UPS.  相似文献   
125.
目的观察鼻窦内镜术(endoscopic sinu ssurgery,ESS)对慢性鼻窦炎伴支气管哮喘患者哮喘发作的影响。方法对210例慢性鼻窦炎患者施行ESS术,其中伴有支气管哮喘病史者42例(20.0%)。210例患者均于术前、术后采用酶联免疫吸附测定法(ELISA)检测外周血单个核细胞(PBMC)培养上清液中的白细胞介素4(IL-4),干扰素γ(IFN-γ),可溶性白细胞介素2受体(sIL-2R)和可溶性IgE低亲和力受体(solube CD23,sCD23)的含量,并与20例正常对照组进行比较。通过主观和客观标准评定42例患者哮喘发作及对皮质类固醇的耐受状况,并对术后患者进行为期1年(10例)和3年(32例)的随访。结果鼻窦炎合并支气管哮喘患者术前PBMC培养上清液中IL-4,sIL-2R、sCD23含量较对照组显著升高,而IFN-γ含量较对照组显著减少。术后IL-4、sIL-2R、sCD23含量较对照组显著降低,而IFN-γ含量显著增高。术后哮喘改善水平由随访术后1年的45%提高到术后3年的70%。42例中32例(76%)哮喘发作次数明显减少,术前长期服用类固醇的2l例中,14例(67%)减少了对口服类固醇的使用。结论ESS对慢性鼻窦炎伴支气管哮喘患者的治疗有较满意的远期疗效。ESS能调节IL-4、IFN-γ sIL-2R、sCD23水平,降低哮喘的发作频率和对类固醇的依赖。  相似文献   
126.
BACKGROUND: Researches on diabetic nervous system lesion are mainly focus on peripheral nerve and vegetative nerve, so there are few investigations on diabetic pseudotabes. OBJECTIVE: To investigate the electrophysiological examinations on the diagnosis of diabetic pseudotabes. DESIGN: Case study. SETTING: Department of Electrophysiology and Department of Neurology, Zhongshan Hospital Affiliated to Xiamen University. PARTICIPANTS: A total of 4 patients with type 2 diabetes mellitus, including 3 males and 1 female aged from 50 to 72 years, were selected from Department of Neurology, Zhongshan Hospital Affiliated to Xiamen University from March 2002 to February 2005. All accepted subjects met the modified diagnostic criteria of diabetes mellitus, which was set by American Diabetes Mellitus Association (ADA) in 1997. Otherwise, the subjects had typical symptoms and physical signs of spinal posterior funiculus damage. However, patients with spinal cord lesion which was caused by other factors were excluded. All accepted subjects provided the confirmed consent. METHODS: Nicolet NT electromyography (EMG)/evoked potential meter (made in the USA) was used to detect spinal cord conduction velocity (SCCV), somatosensory evoked potential (SEP) of lower limbs, motor nerve conduction velocity (MNCV) and sensory nerve conduction velocity (SNCV) of extremities. Determining criteria: Measurements were performed based on the laboratory standards. SCCV, which was less than lower limit of normal value (T2–12: 40–55 m/s, T12–L4: 20–41 m/s, T2–L4: 36–45 m/s), was regarded as abnormal. SEP value of lower limbs: P40, P60 and PF, which were more than standard deviation of normal value (x(—)+2.5), were regarded as the abnormality. Normal value of P40, P60 and PF latencies (x(—)±s) in this study: P40, P60 and PF in males were (37.6±1.9) ms, (59.8±3.9) ms and (7.6±0.9) ms, respectively; meanwhile, those in females were (35.5±1.7) ms, (55.2±2.7) ms and (6.3±0.7) ms, respectively. MNCV and SNCV, which were less than 50 m/s in upper limbs and 40 m/s in lower limbs, were regarded as the abnormality. MAIN OUTCOME MEASURES: Electrophysiological examinations. RESULTS: All 4 patients with type 2 diabetes mellitus were involved in the final analysis. ① SCCV: Among 4 patients, SCCV of three patients was decreased in T2–12, T12–L4 and T2–L4, and that of the other one was decreased in T2–12 and T2–L4; however, SCCV in T12–L4 was normal. There was significant difference as compared with normal value (P < 0.01). ② SEP of lower limbs: SEP values of lower limbs were abnormal in all 4 patients. Among them, P40, P60 and PF latencies of two patients were delayed; P40 of one patient was delayed and PF was not drained out; P40 and P60 of the last one were delayed and PF was normal. ③ MNCV and SNCV: The MNCV and SNCV were normal in one patient and abnormal in three patients. The results demonstrated that MNCV and SNCV of extremities decreased; especially, sensory nerve action potential (SNAP) of both lower extremities of one patient were not drained out. CONCLUSION: Detections of SCCV, SEP of lower limbs, MNCV and SNCV of extremities are helpful to investigate whether peripheral nerve and deep sensory passage are damaged or not and determine whether deep sensory damage is caused by peripheral nerve and spinal posterior funiculus.  相似文献   
127.
风疹易感人群婚前风疹疫苗接种预防先天性风疹综合征   总被引:1,自引:0,他引:1  
目的探讨婚前风疹易感人群风疹疫苗接种在提高孕妇对风疹的免疫力,预防先天性风疹综合征中的作用.方法对10 913例婚前风疹病毒抗体IgG阴性者给予国产风疹减毒活疫苗注射.3个月随防671例,比较风疹疫苗接种前后该地区孕妇近期风疹感染的发病率.结果818例风疹病毒抗体IgG阴性者接种后抗体转阳率为99.8%.风疹疫苗接种前后3年孕妇近期风疹感染率分别为0.37%及0.08%,有明显下降,有非常显著差异(P<0.001).结论应用国产风疹减毒活疫苗对婚前易感人群作预防接种可提高育龄妇女对风疹的免疫力,降低孕期风疹感染的发生率,是预防先天性风疹综合征及风疹致畸的有效、安全措施.  相似文献   
128.
Pregnant and parenting adolescents living in inner cities are at risk for acquiring HIV through unprotected sexual activity. In addition to individual risk behaviors, a lack of socioeconomic and other environmental resources create risk environments that make certain communities vulnerable to both adolescent pregnancy and HIV/AIDS. Research indicates that adolescent parents, many who have histories of childhood trauma, may use their experience of young parenthood and the concomitant feelings of parental protectiveness as a source of renewed hope for their future. The purpose of this report is to explore the relationship between history of childhood abuse and high risk behaviors in adolescent Latino mothers and fathers enrolled in a randomized clinical trial of a culturally rooted, couple-focused HIV prevention program. In addition, this report describes the HIV prevention program that was designed specifically for young Latino parents wherein maternal and paternal protectiveness are viewed as intrinsic and developing critical factors that promote resiliency and motivate behavioral change.  相似文献   
129.
The aim of this study was to compare the demographic and clinical characteristics of individuals with affective disorders who had attempted suicide at some time in their lives and those who had not made a suicide attempt. In a Chinese rural community, individuals with suicide attempt (N = 30) and those without suicide attempt (N = 166) were assessed with Present State Examination (PSE). Attempters had a significantly higher level of family economic status, higher rate of lifetime depressed mood and hopelessness, and delusions than nonattempters. The logistic regression models also indicated that depressed mood and hopelessness were the most important predictors of suicide attempts. No significant difference in treatment condition was found between attempters and non-attempters. Early identification and interventions focusing on reducing depressed mood, hopelessness, and controlling psychotic symptoms may be helpful in reducing the risk of suicide attempts among individuals with affective disorders residing in the community.  相似文献   
130.
In this work the feasibility of separating fat and water signals using the balanced steady-state free precession (SSFP) technique is demonstrated. The technique is based on the observation (Scheffler and Hennig, Magnetic Resonance in Medicine 2003;49:395-397) that at the nominal values of TE = TR/2 in SSFP imaging, phase coherence can be achieved at essentially only two orientations (0 degrees and 180 degrees ) relative to the RF pulses in the rotating frame, under the assumption of TR < T2, and independently of the SSFP angle. This property allows in-phase and out-of-phase SSFP images to be obtained by proper choices of the center frequency offset, and thus allows the Dixon subtraction method to be utilized for effective fat-water separation. The TR and frequency offset for optimal fat-water separation are derived from theories. Experimental results from healthy subjects, using a 3.0 Tesla system, show that nearly complete fat suppression can be accomplished.  相似文献   
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