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41.
槲寄生化学成分的研究——Ⅷ.2,3-丁二醇单葡萄糖甙的分离和结构 总被引:6,自引:0,他引:6
From the ethanol extract of Viscum coloratum (Kom.) Nakai , a giucoside ofaliphatic diol and three other glucosides were isolated. Based on chemical and spectroscopic analysis,the structures have been elucidated as 2-β-D- glucosyl-3- methylpropanol (Ⅷ), syringin (Ⅸ),eleatheroside E(Ⅹ) and syringenin-4'-O-D-apiosylglucoside (Ⅺ). Ⅷ is a new glucoside of aliphaticdiol and named 3-β-D-glucopyranosyloxy-butanol-2. Three other compounds (Ⅸ~-Ⅺ) were foundfor the first time in this plant. 相似文献
42.
Inter- and intrasensory modality matching in children with hand-eye coordination problems: exploring the developmental lag hypothesis 总被引:1,自引:1,他引:0
H. Sigmundsson R P. Ingvaldsen HT A. Whiting 《Developmental medicine and child neurology》1997,39(12):790-796
This study set out to explore the suggestion that the problems experienced by 8-year-old children diagnosed as clumsy in the area of hand-eye coordination (HECP) might be attributed to a developmental lag. The performances of this group of HECP children were compared with those of groups of 5-year-old and 8-year-old controls without such deficits, when required to carry out a task involving pointing, without vision, to targets located, visually, visually/proprioceptively, or proprioceptively, the dependent variable being the distance error score from the centre of the target. The performances of the HECP children, when vision or vision/proprioception was used to locate the targets, were shown to be inferior to those of the two control groups of children thereby supporting a visual deficit hypothesis. When the targets had to be located proprioceptively, the performance of the HECP children was shown to be similar to that of the 5-year-olds, while both groups were inferior to the 8-year-olds, thereby supporting a developmental lag hypothesis in proprioceptive terms. However, when the scores for the preferred and non-preferred hands were analysed separately a marked deterioration in the performances of both the 5-year-old controls and the HECP children was observed while the 8Jyear-old controls were unaffected. While this finding supports a developmental lag explanation of the inferior performances of the HECP children, it was necessary to qualify such an explanation when the within-group performances using the preferred and non-preferred hands were compared. Only the HECP children, under the visual/proprioceptive or proprioceptive conditions, showed significant performance differences, in. favour of the preferred hand. This finding was taken as a suggestion that the developmental lag exhibited by the HECP children might have pathological overtones possibly related to the development of the corpus callosum. 相似文献
43.
Thirteen methods of prepararing leukocyte-poor red blood cells were compared for their effectiveness in removing leukocytes. When the starting material was six to ten days old, the residual leukocyte count was three to four times lower than when fresh material was used and no granulocytes could be found. The most effective manual procedure was a single upright sedimentation of six- to ten-day-old saline-diluted red cells. Inverted sedimentation was no more effective in leukocyte depletion than upright sedimentation. Automated cell processors were no more effective than several of the better manual methods. Freezing and deglycerolizing resulted in a ten-fold improvement in leukocyte removal with less red blood cell loss but at higher cost than the nonfreezing methods. The study indicates that unless the minimal leukocyte count of frozen red blood cells is essential, a single upright sedimentation of saline-diluted, six- to ten-day-old red blood cells is currently the most effective procedure for preparing leukocyte-poor red blood cells. 相似文献
44.
Martins LC de Oliveira Corvelo TC Oti HT do Socorro Pompeu Loiola R Aguiar DC dos Santos Barile KA do Amaral RK Barbosa HP Fecury AA de Souza JT 《World journal of gastroenterology : WJG》2006,12(7):1120-1124
AIM:To investigate the ABH and Lewis antigen expres-sion in erythrocytes,saliva and gastric epithelium,aswell as the association between H pylori and the pres-ence of gastric epithelial lesions.METHODS:The distribution of ABH and Lewis bloodgroup antigens in erythrocytes,saliva and gastric mu-cosa of H pylori-infected gastric ulcer patients was ana-lyzed.Forty-two patients with gastric ulcer were studied,and fifty healthy individuals were used as control group.The blood group antigens were determined by directhemagglutination,dot-ELISA and immunohistochemi-cal methods in erythrocytes,saliva and gastric mucosaspecimens,respectively.Diagnosis for H pylori infectionwas performed by conventional optical microscopy andELISA.RESULTS:A higher seroprevalence of IgG H pylori spe-cific antibodies was observed in gastric ulcer patients(90%)compared to the control group(60%).We ob-served a significant increase of phenotypes O,A_2 andLewis b in H pylori-infected patients.The expression ofthese antigens had progressive alterations in areas of ul-cerous lesions and intestinal metaplasia. CONCLUSION:ABH and Lewis blood group antigensare a good indicator for cellular alterations in the gastricepithelium. 相似文献
45.
Maarten HT Zwartbol Ina Rissanen Rashid Ghaznawi Jeroen de Bresser Hugo J Kuijf Kim Blom Theo D Witkamp Huiberdina L Koek Geert Jan Biessels Jeroen Hendrikse Mirjam I Geerlings 《Journal of cerebral blood flow and metabolism》2021,41(11):3127
We determined the occurrence and association of cortical cerebral microinfarcts (CMIs) at 7 T MRI with risk factors, neuroimaging markers of small and large vessel disease, and cognitive functioning. Within the Medea-7T study, a diverse cohort of older persons with normal cognition, patients with vascular disease, and memory clinic patients, we included 386 participants (68 ± 9 years) with available 7 T and 1.5 T/3T brain MRI, and risk factor and neuropsychological data. CMIs were found in 10% of participants and were associated with older age (RR = 1.79 per +10 years, 95%CI 1.28–2.50), history of stroke or TIA (RR = 4.03, 95%CI 2.18–7.43), cortical infarcts (RR = 5.28, 95%CI 2.91–9.55), lacunes (RR = 5.66, 95%CI 2.85–11.27), cerebellar infarcts (RR = 2.73, 95%CI 1.27–5.84) and decreased cerebral blood flow (RR = 1.35 per −100 ml/min, 95%CI 1.00–1.83), after adjustment for age and sex. Furthermore, participants with >2 CMIs had 0.5 SD (95%CI 0.05–0.91) lower global cognitive performance, compared to participants without CMIs. Our results indicate that CMIs on 7 T MRI are observed in vascular and memory clinic patients with similar frequency, and are associated with older age, history of stroke or TIA, other brain infarcts, and poorer global cognitive functioning. 相似文献
46.
Duc T Quach Toru Hiyama Fumio Shimamoto Quang D Le Linh X Ho Nhu HT Vu Masaharu Yoshihara Naomi Uemura 《World journal of gastroenterology : WJG》2014,20(17):5087-5091
AIM:To assess the value of a new test for the diagnosis of Helicobacter pylori(H.pylori) infection,Rapirun H.pylori Antibody Stick(Rapirun Stick),in a Vietnamese population.METHODS:Eligible patients without previous history of H.pylori eradication were recruited.Rapid urease test(RUT) and histologic examination were used to diagnose the H.pylori infection.Patients were considered H.pylori positive when the RUT results were positive and/or the bacteria were detected histologically.Rapirun Stick tests were performed using urine samples,and the results were compared with the other 2 methods.RESULTS:We enrolled 200 patients with a mean age of 36(range,18-76) years.There were 116 females and 84 males.Of the 200 patients,111(55.5%) were diagnosed as being H.pylori positive.The sensitivity,specificity,and accuracy of the Stick test were 84.7%,89.9%,and 87.0%,respectively.There were 17(8.5%) falsenegative patients and 9(4.5%) false-positive patients.CONCLUSION:The Rapirun Stick test has high sensitivity,specificity,and accuracy for the diagnosis of H.pylori infection in the Vietnamese population.The test can be clinically applied in Vietnamese populations. 相似文献
47.
48.
Sulfate-induced expansion resulting from the formation of ettringite in sulfate-bearing soil stabilised with calcium-based stabilisers is a problematic issue with technical and economic implications. Thus, this research examines the viability of the co-addition of lime (L) and silica fume (S) at varying binder dosages (4, 6, and 10 wt%), with a view of establishing the optimum blend of L–S for suppressing the ettringite-induced expansion of artificially high sulfate-dosed soil (kaolinite-K and gypsum-G). To do so, a series of laboratory specimens, designed using different gypsum and lime concentrations, were investigated using unconfined compression strength (UCS), linear expansion, and derivative thermo-gravimetric analysis (DTG) as the main criteria for the examination. The research outcomes indicated that the increasing substitution of L with S induces a gradual reduction on the UCS and linear expansion at binder levels of 4 and 6 wt%, while its usage in a high binder level (10 wt%), can yield an expansion reduction, with no compromise on the UCS performance. Therefore, silica fume has the potential for restricting ettringite formation and suppressing the expansion, of which 3L7S is the optimum blending ratio for suppressing the expansion. 相似文献
49.
50.