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951.
人早孕期蜕膜和绒毛外滋养层细胞的免疫组织化学研究   总被引:7,自引:0,他引:7  
侵入蜕膜组织的绒毛外滋养层细胞在HE染色标本上不易辨认。我们用免疫组织化学,ABC法,过氧化物-抗过氧化物酶标记蜕膜组织中的hCG与hPL阳性细胞。结果证明,子宫内膜中只要有一个绒毛外滋养层细胞存在就能被显示出来。这对提高妊娠诊断,防止残留滋养层细胞的增生与恶性病变很有意义。我们在蜕膜组织中还发现3类胎盘激素阳性细胞:hCG阳性细胞,hPL阳性细胞及hCG与hPL均为阳性的细胞。这一发现,证明了蜕膜有内分泌功能。  相似文献   
952.
The mechanism by which nerve - muscle contacts are reduced during postnatal development of the rat soleus muscle was investigated using electrophysiological methods. Between days 7 and 9 after birth, soleus muscle fibres lose 0.19–0.24 terminals per muscle fibre within 24 h. A much more rapid loss of contacts is seen when muscles are exposed in vitro to acetylcholine (10−3 g/ml). In this case 0.67–0.87 terminals per muscle fibre lose contact within 2 h. The loss of neuromuscular contacts induced by acetylcholine can be reduced by preincubating the muscles in solutions containing acetoxymethyl ester of 1,2-bis(2-amino-phenoxylethane-N,N1;N1-tetraacetic acid (BAPTA-AM), a Ca2+ chelating agent that enters cells and reduces the Ca2+ transients inside the cell. Treatment of muscles with nifedipine, which blocks dihydropyridine-sensitive (L-type) Ca2+ channels, also reduced the acetylcholinesterase-induced loss of neuromuscular contacts. The results indicate that transient increases in Ca2+ inside nerve terminals contribute to loss of neuromuscular contacts, and that these increases occur by Ca2+ entry through L-type channels.  相似文献   
953.
954.
作者采用显微外科技术切除脑脓肿40例,在切除前,先用自制三通装置穿刺脓肿,并用10%甲醛溶液及庆大霉素溶液冲洗脓腔,然后在手术显微镜下切除脓壁。随访3~5年,治愈率98.0%(38例),复发1例,死亡2例。  相似文献   
955.
Summary This study was designed to compare the degree of reactive astrogliosis occurring around a puncture wound in the brain of normal rats and at different intervals after a similar puncture wound in rats with a portocaval anastomosis. The gliosis was evaluated by the number of astrocytes, the thickness of their processes and the intensity of the glial fibrillary acidic protein immunoreactivity. After the puncture wound in the brain of rats with a portocaval anastomosis, the gliosis varied at different intervals being: (1) decreased at 10 days, (2) markedly increased at 5 weeks and (3) significantly decreased at 8, 12, and 16 weeks. These findings suggest that 5 weeks after portocaval anastomosis, an active proliferation of the metabolically altered astrocytes occurs with heightened synthesis of glial fibrillary acidic protein in the period of adaptive compensation, the so-called compensatory rebound. At 8 weeks or more after portocaval anastomosis, these altered astrocytes were considered to be in the phase of decompensation and incapable of maintaining the reactive response which occurred in normal rats. The compensatory rebound and decompensatory decline illustrate the dynamic plasticity of the reactive astrogliosis.Supported by grant from the National Foundation of Natural Sciences No. 386-0956. This paper was read at the XIth International Congress of Neuropathology, September 7, 1990 in Kyoto, Japan  相似文献   
956.
BACKGROUND AND PURPOSE: Both stroke and the apolipoprotein E (APOE) epsilon4 allele increase the risk of dementia. However, the interaction between stroke and APOE on dementia is still unclear. We addressed this topic by using a longitudinal design. METHODS: We followed up a community cohort of 1301 subjects aged >/=75 years, who did not have dementia at baseline. Among them, 92 subjects had a history of stroke (from 3 months to 16 years before baseline interview). After the 3-year follow-up, 224 dementia cases had been diagnosed. During the period of follow-up, 91 subjects had a first occurrence of stroke (incident stroke). The APOE genotype was known for 985 subjects. Cox proportional hazards regression models were constructed to estimate the risk for dementia in terms of relative risks (RRs) for stroke and the APOE epsilon4 allele, with adjustment for age, sex, education, systolic blood pressure, antihypertensive medication use, and heart disease. RESULTS: In the entire study population, RRs for dementia related to history of stroke and incident stroke were 1.7 (95% CI, 1.1 to 2.6) and 2.4 (95% CI, 1.6 to 3.5), respectively, after adjustment for all potential confounders. Subjects with stroke that occurred within 3 years before baseline had RR of 2.4 (95% CI, 1.4 to 4.2), whereas those with stroke occurring >3 years before baseline had RR of dementia of 1.1 (95% CI, 0.6 to 2.3). Among those with APOE information, individuals with only history of stroke (that occurred within 3 years before baseline) had RR of 3.1 (95% CI, 1.4 to 6.6), individuals with only the APOE epsilon4 allele had RR of 1.7 (95% CI, 1.1 to 2.5), and individuals with both factors had RR of 5.3 (95% CI, 2.1 to 13.4). The corresponding figures when incident stroke was examined instead of history of stroke were 2.3 (95% CI, 1.3 to 4.1), 1.7 (95% CI, 1.1 to 2.4), and 4.6 (95% CI, 2.0 to 10.6), respectively. The RR of interaction term for history of stroke and APOE epsilon4 was 1.1 (95% CI, 0.3 to 3.8; P=0.8). The corresponding figure was 1.2 (95% CI, 0.4 to 4.4; P=0.7) for incident stroke and APOE epsilon4. Furthermore, the RRs of dementia without any stroke and dementia with stroke in relation to APOE epsilon4 were 1.6 (95% CI, 1.1 to 2.3) and 1.2 (95% CI, 0.6 to 2.4), respectively. In addition, the APOE epsilon4 allele was not significantly related to the occurrence of stroke (RR=0.8; 95% CI, 0.5 to 1.5). CONCLUSIONS: A relatively fresh stroke is a risk factor for dementia. APOE epsilon4 increases the risk of dementia without stroke but not dementia with stroke. Our data do not support a multiplicative effect of stroke and the APOE epsilon4 allele on the risk of dementia. However, both factors seem to have an additive effect on the risk of dementia. The APOE epsilon4 allele does not increase the risk of stroke in this Swedish elderly population.  相似文献   
957.
朱平凤 《中南药学》2003,1(3):151-152
目的 分离和测定非那甾胺中5β-异构体杂质。方法 高效液相色谱法,色谱柱为DiamonsilTMC18柱(4.6 mm×200 mm,5μm),流动相为乙腈-四氢呋喃-水(3:1:8),流速为1.5 mL·min-1,检测波长为210nm,柱温25℃。结果 非那甾胺与5β-异构体能有效分离,两者最低检测浓度均为0.05μg·mL-1。结论 本法操作简便,重现性好,可有效控制非那甾胺的质量。  相似文献   
958.
研究注射用盐酸丁咯地尔对细菌内毒素检查试验的干扰情况 ,并建立其细菌内毒素检查的方法。按《中国药典》 2 0 0 0年版二部附录ⅪE细菌内毒素检查法和附录ⅪⅩF细菌内毒素检查法应用指导原则进行试验。本品在 0 33mg·ml-1稀释浓度下无干扰作用 ,L =1 5EU·mg-1。本品可用细菌内毒素检查法替代热原检查法  相似文献   
959.
目的:统计分析我院消化科作用于消化系统药物用药情况,提高临床合理用药水平。方法:应用电脑统计2002年9月4日~2003年5月6日我院消化科用药有效数据,采用金额排序法和DDDs排序法,对作用于消化系统药物进行统计分析。结果:用药金额和DDDs最高的是抗酸药及治疗消化系溃疡药类,具体药物是奥美拉唑。结论:我院消化科对作用于消化系统药物的使用基本合理。  相似文献   
960.
氟尿苷在大鼠子宫组织内的分布及药动学研究   总被引:5,自引:0,他引:5       下载免费PDF全文
王鹏  朱珠  付强 《中国药学杂志》2003,38(3):203-207
 目的研究氟尿苷(FUDR)在大鼠血清及子宫组织内的分布、代谢特征并进一步探讨FUDR与氟尿嘧啶(5FU)转化关系。方法建立了大鼠血清和子宫组织中FUDR及5FU的HPLC测定方法。130只雌性Wistar大鼠随机分组,尾静脉恒速输注FUDR或5FU,并按照设计的时间点断头放血,采集血及子宫组织标本,测定各标本中的FUDR及5FU浓度。考察FUDR在大鼠体内的动力学特征及其与5FU的转化关系,以及FUDR与5FU在大鼠子宫组织的分布特征。结果在本实验的剂量下,FUDR在大鼠体内呈现线性代谢特征,而其代谢物5FU则符合非线性特征。静脉输注时,5FU具有较强的血液/子宫组织穿透能力,其子宫组织5FU浓度(2.19~5.87) μg·g-1与血液浓度(4.52~5.41) mg·L-1相当。而输注FUDR时,子宫组织内的FUDR浓度很低,代谢物5FU的浓度(2.53~5.11)μg·g-1却与输注5FU时的相当,而此时血清5FU浓度(0.47~0.83) mg·L-1却远低于输注5FU时的血清浓度。结论FUDR具有更强的子宫组织亲和力,静脉输注FUDR后子宫组织内其代谢物5FU的浓度较高。  相似文献   
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