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971.
大肠癌组织中端粒酶活性的研究   总被引:23,自引:0,他引:23  
Zhao D  Zhang W  Jin S 《中华肿瘤杂志》1998,20(3):199-201
目的研究大肠癌组织及相应癌旁组织中的端粒酶活性,探讨其作为肠癌肿瘤标记物的可能性。方法采用TRAP方法研究了40例大肠组织(包括37例大肠癌,3例良性大肠疾病)和20例相应癌旁上皮组织中的端粒酶活性表达。结果20例癌旁上皮和3例良性疾病组织中,端粒酶活性表达均为阴性;而37例大肠癌组织中,35例显示端粒酶活性表达为阳性,阳性率为94.6%。结论端粒酶是特异性较强的恶性肿瘤基因标志,有可能成为大肠癌早期诊断和治疗的理想标志物  相似文献   
972.
The Kampo (Japanese herbal) medicine "Juzen-Taiho-To" (TJ-48), which was prepared by decocting a concoction (formula), contains ten kinds of herbs and has several immunostimulating activities. In order to determine the contribution of each herbal component, the complement-activating and mitogenic activities of the hot water extract as well as the polysaccharide fraction from each herb were tested. Hot water extracts of Glycyrrhizae radix, Astragali radix, and Atractylodes lanceae rhizoma showed significant mitogenic activity whereas that of Cinnamomi cortex showed potent complement-activating activity. However, the exclusion of any single component herb whether active or not on its own did not result in a loss or an increase of the overall activity of TJ-48. The polysaccharide fraction from Glycyrrhizae radix showed the most potent of both activities among the same fractions from the other nine herbs, and reduced both activities after periodate oxidation, thus indicating that the carbohydrate moiety may contribute to both activities.  相似文献   
973.
S F Zhao 《中华妇产科杂志》1991,26(5):262-5, 321
A prospective study to evaluate the role of the insufflatable abdominal girdle (IAG) in shortening the second stage of labor was carried out in 160 consecutive full-term normal primiparas with vertex presentation. The parturients were randomized in order into 2 groups: the study group (using IAG) and the control group, each containing 80 cases. The average duration of second stage of labor was 40'23" for the cases of the study group and 59'59" for the controls. The difference was statistically significant (P less than 0.01). The average duration between the appearance of fetal head at the vulva to the complete birth of the baby was 11'56" and 20'56" respectively and again the difference was highly significant (P less than 0.01). Vacuum exteractor necessary for the termination of labor was performed in 15 cases of the controls and only 5 cases of the study group. There was no difference of incidence of abnormal fetal heart rate and appearance of meconium-stained aminotic fluid between two groups. The average Apgar score at 1 minute after birth was 9.78 for the study group and 9.88 for the control group (P greater than 0.005). Results of blood gas analysis of umbilical artery and vein immediately after birth, including pH, PO2, PC2 and BE, were all within normal ranges. Maternal blood pressure, pulse, respiratory rate and blood gas analysis were monitored during the second stage of labor and no significant difference was observed between two groups.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
974.
975.
976.
青少年近视某些影响因素研究   总被引:12,自引:0,他引:12  
  相似文献   
977.
本文从中药黄藤的根及根茎中分得三种季铵生物碱,化学及光谱数据证明,一为掌叶防己碱(巴马汀),二为药根碱,三系伪非洲防己胺碱。后者为国内首次得到的一种天然伪原小檗碱型生物碱。  相似文献   
978.
979.
OBJECTIVE: This study longitudinally described rates of posttraumatic stress disorder (PTSD) in two groups with different levels of severity of exposure to an earthquake in North China. The effects of diagnostic criteria on the frequency of detected PTSD were also examined. METHOD: Subjects were randomly sampled in two villages at different distances from the earthquake epicenter. A total of 181 and 157 subjects were assessed at 3 months and 9 months after the earthquake, respectively, for PTSD by using both DSM-IV and DSM-III-R criteria. The brief version of the World Health Organization Quality of Life Assessment and three subscales of the SCL-90-R were also administered at both assessment points. RESULTS: The village with a higher level of initial exposure to the earthquake and a higher level of postearthquake support had a lower frequency of PTSD than the village with a lower level of initial exposure and less postearthquake support. The rate of onset of DSM-IV PTSD within 9 months for the two villages was 19.8% and 30.3%, respectively. In both villages, the rate of onset of earthquake-related PTSD within 9 months was 24.2% by using DSM-IV criteria and 41.4% by using DSM-III-R criteria. The introduction in DSM-IV of a criterion requiring clinically significant distress or impairment in functioning for a diagnosis of PTSD was a major contributor to the lower rate of DSM-IV PTSD. CONCLUSIONS: PTSD may be as prevalent and persistent in disaster victims in China as in those elsewhere. Prompt and effective postdisaster intervention could mitigate the impact of initial exposure and reduce the probability of PTSD occurrence. Caution should be used in comparing rates of postdisaster PTSD identified by using different diagnostic criteria.  相似文献   
980.
BACKGROUND AND PURPOSE: Studies show that blocking the activation of caspases by the caspase inhibitors z-VAD.FMK and z-DEVD.FMK can reduce ischemic neuronal injury after cerebral ischemia. Because the severity of ischemia was mild in some studies, we tested the efficacy of these caspase inhibitors on moderately severe but transient forebrain and focal ischemic insults in the rat. METHODS: Various regimens of z-VAD, z-DEVD, and control DMSO were given to rats subjected to either 4-vessel occlusion ischemia (4-VO, 10-minute occlusion, 7-day survival) or distal middle cerebral artery occlusion (MCAo, 90-minute occlusion, 22.5-hour survival). In global ischemia, treatments were given immediately after ischemia (experiment 1) or as preischemic and postischemic treatments (experiment 2). Three focal ischemia experiments were done. Injection times were 60 minutes into ischemia (experiment 1) and 60 minutes into ischemia plus 30 and 120 minutes after ischemia (experiment 2). Experiment 3 was identical to experiment 2 except that a 30-minute preischemia treatment was instituted. Core normothermia was maintained in all experiments during ischemia. However, in the last focal and global experiments, core and brain temperatures, respectively, were also measured after ischemia with telemetry probes. Because hyperthermia accompanied z-DEVD treatment, an extra z-DEVD-treated group (MCAo) was included with temperature clamped at normothermia. RESULTS: Neither z-VAD nor z-DEVD significantly reduced CA1 injury after global ischemia. In focal ischemia, both drugs significantly reduced infarction, but only in the third experiment, and the prevention of hyperthermia that accompanied z-DEVD treatment did not alter this. CONCLUSIONS: These results suggest a detrimental role of caspases in moderately severe focal but not global cerebral ischemia.  相似文献   
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