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81.
Summary Diazepam was metabolized by human foetal liver microsomes to N-desmethyldiazepam and N-methyloxazepam as early as the 13th week of gestation. The metabolic activity was lower than that of microsomes from adult human liver. Diazepam was shown mainly to be hydroxylated to N-methyloxazepam at substrate concentrations higher than 0.1 mM. Diazepam levels above 1.0 mM were inhibitory to the overall metabolic reaction. SKF 525-A inhibited diazepam metabolism by foetal liver microsomes at a concentration of 0.1 mM. The addition of diazepam to foetal and adult human liver microsomes resulted in a type II spectral change. Its inhibition by carbon monoxide indicated that biotransformation of diazepam was performed by the cytochrome P-450-linked mono-oxygenase system. 相似文献
82.
目的 用Rh阳性血换血治疗 12例新生儿Rh溶血病获得成功。方法 血液选用ABO与婴儿同型的肝素抗凝血 ,换血前严格做血交叉和抗人球蛋白实验 ,不测献血员Rh血型 ,换血量为 180ml/kg。 结果 换血后大多数婴儿黄疸无明显加重 ,仅一例因血清胆红素 >3 4 0 μmol/L而需第二次换血 ,所有病例均痊愈出院 ,平均住院天数为 (12± 4)d。结论 在病情紧急时 ,用Rh阳性血换血治疗 ,是一项安全有效的替代措施。 相似文献
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Margaret K. Hargreaves PhD Maciej S. Buchowski PhD Robert E. Hardy MD MPH Susan R. Rossi RN PhD Joseph S. Rossi PhD 《American journal of obstetrics and gynecology》1997,176(6):s255
Modification of dietary fat and fiber could help prevent cancers of the breast, endometrium, and ovary that are prevalent in African-American women. Dietary intervention programs aimed at reducing fat intake have had mixed results in this population. The transtheoretic model is proposed for achieving dietary change. Strategies for changing health behaviors in African-American women include heightening sensitivity to cultural values among health educators and the use of multiple strategies to reinforce messages. To stimulate healthier eating, it is important to incorporate the distinct habitual eating patterns into innovative intervention methods, using effective behavioral change methods. (Am J Obstet Gynecol 1997;176:S255-64.) 相似文献
86.
Serum levels of C3 and Factors I and B in minimal change disease 总被引:2,自引:0,他引:2
Abstract Background: Relapses are an important problem in minimal change disease, which accounts for most of the cases of childhood nephrotic syndrome. Because of defects in the humoral immune system, patients are predisposed to infection in nephrotic syndrome and infection is the most important complication that determines mortality and morbidity.
Methods: In this study, serum levels of Factors I and B and C3 were studied to evaluate the relationships between nephrotic syndrome and infection in 17 children with nephrotic syndrome (24–96 months of age) and 10 healthy children (27–84 months of age).
Results: Serum levels of Factors I and B were found to be lowered in the active disease group compared with the control group. These values were lowest for the infection group. Although it was observed that these values increased with steroid treatment, they did not reach normal levels. The parameters in remission were not different from the parameters in the control subjects. The serum level of C3 was found to be high during the active disease state and returned to normal levels during remission.
Conclusions: The patients with active minimal change disease had infections such as peritonitis, septicemia and urinary tract infection because of low concentrations of Factors I and B in their sera. 相似文献
Methods: In this study, serum levels of Factors I and B and C3 were studied to evaluate the relationships between nephrotic syndrome and infection in 17 children with nephrotic syndrome (24–96 months of age) and 10 healthy children (27–84 months of age).
Results: Serum levels of Factors I and B were found to be lowered in the active disease group compared with the control group. These values were lowest for the infection group. Although it was observed that these values increased with steroid treatment, they did not reach normal levels. The parameters in remission were not different from the parameters in the control subjects. The serum level of C3 was found to be high during the active disease state and returned to normal levels during remission.
Conclusions: The patients with active minimal change disease had infections such as peritonitis, septicemia and urinary tract infection because of low concentrations of Factors I and B in their sera. 相似文献
87.
Phenotypic shift in human differentiated gastric cancers from gastric to intestinal epithelial cell type during disease progression 总被引:3,自引:1,他引:3
Akemi Yoshikawa Ken-ichi Inada Takasuke Yamachika Nobuyuki Shimizu Michio Kaminishi Masae Tatematsu 《Gastric cancer》1998,1(2):134-141
Background. The phenotypic expression of tumor cells is widely thought to resemble that of the tissue of origin. In the present study,
to assess phenotypic changes that occur with disease progression, we investigated human differentiated gastric cancers at
different depths of invasion for component cancer cell types.
Methods. Using a combined mucin histochemical and immunohistochemical approach, we classified surgical specimens of 301 differentiated
gastric cancers into three types: gastric epithelial cell (G) type, intestinal epithelial cell (I) type and mixed gastric
and intestinal (GI) type, according to the phenotypic differentiation of the component cancer cells. The relation between
the phenotypic type of cancer and their depth of invasion was evaluated.
Results. The proportion of G type cancers was 41.4% in early (tumor invasion of mucosa or submucosa) cases, decreasing to 22.2% in
advanced (tumor invasion of muscularis propia or deeper) cases, whereas the proportion of I type cancers increased with progressive
disease from 23.5% to 31.1% (P < 0.01). Cancers invading the subserosa or deeper included more I type cases and fewer G type than cancers limited to the
mucosa (P < 0.01). In most cases of each phenotypic type, intestinal metaplasia was recognized in the surrounding background mucosa,
but no clear relation was shown between the phenotype of cancers and the degree of intestinal metaplasia in the background
mucosa, suggesting that intestinal metaplasia is not always a preneoplastic lesion.
Conclusions. A phenotypic shift from G to I type expression was observed with the progression of human differentiated gastric cancers.
Intestinalization may occur independently in cancerous and noncancerous gastric mucosa.
Received for publication on May 1, 1998; accepted on Oct. 22, 1998 相似文献
88.
目的探讨烧伤患者三重酸碱平衡紊乱的临床特征与治疗方法。方法回顾性分析我科自1998-01~2004-04发生三重酸碱平衡紊乱的烧伤患者124例,其中呼碱+代酸+代碱85例,呼酸+代酸+代碱39例。所有患者均予祛除原发失衡病因、根据血pH情况补酸补碱、限碱、纠正电解质紊乱等治疗。结果复查血气分析纠正率89.5%,死亡率9.7%。结论休克、吸入性损伤、脓毒症是烧伤患者发生三重酸碱失衡的主要原因。临床以呼碱型三重酸碱失衡多见,呼酸型三重酸碱失衡则大多伴有吸入性损伤。烧伤合并三重酸碱失衡往往缺乏典型临床表现,死亡率较低。及时祛除引起原发失衡的病因是治疗的关键。 相似文献
89.
目的 观察猫视网膜脱离后,视网膜色素上皮细胞(RPE)的形态学改变及行为变化。方法 28只猫利用微穿刺技术将0.25%Healon注入到视网膜下腔造成视网膜脱离。脱离0.5~90d的视网膜用3%戊二醛固定,加工成组织切片,光镜和电镜下观察RPE细胞形态学变化。结果 视网膜脱离24h,视网膜色素上皮细胞顶端突起被短而均匀的指样突起所取代,RPE细胞顶端表面开始出现耸起。随着脱离时间的延长,细胞表面的这种耸起变得更加明显。脱离14d,RPE细胞开始向视网膜下腔迁移,1~2个月后,在视网膜下腔可以观察到一些小的RPE细胞团簇。结论 视网膜脱离后,RPE细胞的形态发生迅速改变,并且依赖视网膜脱离的时间呈进行性进展。视网膜脱离能诱导RPE细胞形状发生变化,这种形状改变可能与细胞的增殖行为有关。 相似文献
90.
目的回顾分析近10年PVR B级的裂孔性视网膜脱离术后复发与玻璃体病变的关系.方法对429例(435只眼)PVR B级的裂孔性视网膜脱离施行巩膜扣带术治疗,其中41只眼术后复发(9.43%),分析术后复发与玻璃体病变的关系.结果术前玻璃体正常组与浓缩组的复发率(3.19%与12.33%)之间差异有显著性(P<0.05);正常组与条索牵引组间的复发率(3.19%与14.29%)之间差异有极显著性(P<0.01);正常组与总体组的复发率(3.19%与9.43%)之间差异有显著性(P<0.05);术前无玻璃体后脱离组与玻璃体后脱离组间的复发率(5.56%与12.90%)之间差异有显著性(P<0.05).视网膜脱离术前各种玻璃体的情况在视网膜脱离复发时均有不同程度地加重.结论PVR B级的裂孔性视网膜脱离术前玻璃体病变和玻璃体后脱离对术后复发影响明显.重视玻璃体-视网膜界面动态变化,可进一步提高手术治愈率. 相似文献