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41.
Seroprevalence of HHV-8 has been studied in Malaysia, India, Sri Lanka, Thailand, Trinidad, Jamaica and the USA, in both healthy individuals and those infected with HIV. Seroprevalence was found to be low in these countries in both the healthy and the HIV-infected populations. This correlates with the fact that hardly any AIDS-related Kaposi's sarcoma has been reported in these countries. In contrast, the African countries of Ghana, Uganda and Zambia showed high seroprevalences in both healthy and HIV-infected populations. This suggests that human herpes virus-8 (HHV-8) may be either a recently introduced virus or one that has extremely low infectivity. Nasopharyngeal and oral carcinoma patients from Malaysia, Hong Kong and Sri Lanka who have very high EBV titres show that only 3/82 (3.7%) have antibody to HHV-8, demonstrating that there is little, if any, cross-reactivity between antibodies to these two gamma viruses.  相似文献   
42.
Objective : The aim of this study was to examine whether intravenous immunoglobulin (IVIg) preparations contain anti-oxLDL and anti-anti-oxLDL antibodies. Background : Oxidized low-density lipoprotein (oxLDL) is one of the major players in atherogenesis. IVIg can reduce atherosclerosis in experimental animal models. Methods : Six commercial IVIg preparations were tested for the presence of anti-oxLDL antibodies by EIA. Inhibition studies were performed with the different IVIg preparations and IgGs purified from a pool of sera from patients with high anti-oxLDL antibody levels. Absorption assays were carried out to evaluate the presence of anti-idiotypes against anti-oxLDL antibodies in IVIg preparations. Results : IVIg preparations tested had various degrees of reactivity towards oxLDL. Absorption experiments suggested that the reactivity was specific because it could be effectively absorbed by oxLDL and not by an irrelevant antigen PPD. The reactivity was smaller than that observed with the IgG from the pool with high anti-oxLDL antibody levels. Inhibition studies with IVIg demonstrated 20-45% inhibition of anti-oxLDL binding to oxLDL, compared to 76% inhibition by the pool with high anti-oxLDL levels. To investigate the presence of anti-idiotypes against anti-oxLDL antibodies within IVIg, F(ab') 2 fragments of IVIg IgG were used to absorb IgG F(ab') 2 fragments from the pool of sera with high anti-oxLDL levels. The decreased binding to oxLDL of the absorbed supernatants shows that IgG F(ab') 2 fragments of the IVIg preparations had high inhibitory capacities ranging from 65 to 90%. Conclusions : IVIg preparations contain both anti-oxLDL and anti-anti-oxLDL activity. This finding may explain the immunomodulating effect of IVIg in atherosclerosis.  相似文献   
43.
维生素K3粉末降解动力学   总被引:1,自引:0,他引:1  
在温度为50~90℃,相对湿度为50~93%范围内,维生素K3的变色速率方程为—dR/dt=kRR,降解速率方程为d(Co—c)/dt=kC(co—c)1/2,光解速率方程为—dR/dt=kP(Ro—R)-1。kRC与热力学温度T和相对湿度RH的关系通式为k=k′exp(—EA/RT)exp(m′RH)。在实验温度和湿度范围内,变色和降解的表观活化能平均值分别为105.51和130.72 kJ/mol。  相似文献   
44.
1. The present study is designed to investigate the brain distribution and plasma pharmacokinetics profiles of chlorogenic acid (CGA) after intranasal administration in Charles–Foster rats to evaluate whether the CGA molecules are transported directly via the nose-to-brain path.

2. The CGA is administered intravenously (IV) and intranasally (IN) at the dose of 10?mg/kg. Further, its concentration in the plasma, cerebrospinal fluid (CSF) and the whole brain is analyzed by HPLC-UV method.

3. The study observes that CGA is rapidly absorbed in plasma with tmax of 1?min similar to IV route after IN administration. The peak plasma concentration and AUC0–24 are higher by 3.5 and 4.0 times respectively in IV administration, compared to IN delivery that represents the significant less systemic exposure of CGA in IN route.

4. However, the concentration of CGA in the brain is 4, 6.5, 5.3, 5.2 and 4.5 times higher at 30, 60, 120, 240 and 360?min, respectively in IN administration compared to IV administration. The exposure of CGA in the brain after IN administration (AUCbrain, IN) was significantly greater (4 times) as compared to the exposure of CGA in the brain (AUCbrain, IV) after IV administration reflecting significant brain uptake of CGA through nasal route. Therefore, IN delivery of CGA can be a promising approach for the treatment of stroke and neurodegenerative disorders.  相似文献   

45.
Radiologically guided balloon catheters were used to dilate 94 gastrointestinal strictures in 92 patients over a 6-year period. Fifty strictures were esophageal and 44 nonesophageal (22 gastroenterostomies, 11 antral-pyloric strictures, four colorectal strictures, four enteroenterostomies, and three miscellaneous strictures). Factors influencing the success of stricture intubation included patient age, stricture location (esophageal vs. nonesophageal and proximal vs. distal esophageal), and association with a surgical anastomosis. Malignancy was associated with greater postdilation irregularity and a smaller increase in stricture diameter, as measured radiographically. Procedural failures occurred in 8% of cases (2% of esophageal and 30% of nonesophageal lesions). Two small, asymptomatic mucosal tears were seen after dilation (one esophageal and one colonic); no other procedural complications occurred. Following successful dilation, 16 patients (17%; six with esophageal and ten with non-esophageal strictures) had recurrence of symptoms during short-term (30-day) follow-up.  相似文献   
46.
47.
M. Thomas  M. Behari  GK Ahuja 《Headache》1991,31(9):613-615
Flunarizine, a calcium channel blocker is considered useful in migraine prophylaxis. We report the first Indian trial with this drug. Fifteen patients with migraine were studied in a 6 months double-blind, placebo-controlled crossover trial. Flunarizine was superior to placebo in reducing the severity and duration of the individual attacks though there was no statistically significant effect on frequency of migraine attacks. The side effects most frequently caused by flunarizine were weight gain and daytime sleepiness.  相似文献   
48.
49.
The degree of inhibition of hepatic succinic dehydrogenase activity by malonate, a competitive inhibitor, did not differ between young and middle-aged lizards. On the other hand, the same parameter increased significantly between middle-aged and old lizards. The percent inhibition of enzyme activity by p-chlorophenoxy acetic acid was also age-dependent, being higher in middle-aged and old than in young lizards.  相似文献   
50.
The positive charge on PEI was partially shielded by forming ionic nanocomposites with a polysaccharide, alginic acid, in aqueous solution, bypassing tedious chemical synthesis. The content of alginic acid was varied systematically to obtain a series of nanocomposites. The nanocomposites were first characterized by assessing the surface charge (zeta potential), size (DLS) and morphology (AFM) followed by evaluation for their DNA interaction ability, cytotoxicity and transfection efficiency on various cell lines. The transfection efficiency of PEI-alginate (6.26%) nanocomposites improved dramatically (2-16-fold over native PEI) in all the cell lines studied. However, a decrease in transfection efficiency was observed on deviating from this optimal concentration of alginic acid in nanocomposites. Cytotoxicity of PEI-alginate/DNA complexes was nearly abolished on increasing the concentration of alginic acid in nanocomposites. PEI-alginate (6.26%) nanocomposites also delivered SiRNAs efficiently into mammalian cells, resulting in 80% suppression of GFP expression. The cellular uptake and endosomal escape of PEI-alginate nanocomposites and PEI were found to follow a similar route when transfection was carried out in presence of chloroquine, bafilomycin A1, cytochalasin B and methyl-beta-cyclodextrin. The results demonstrate a versatile vector that can be used for efficient cytoplasmic delivery of a broad range of nucleic acids.  相似文献   
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