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41.
在动物实验的基础上,比较了抗AFP单克隆抗体(mAb)和抗AFP多克隆抗体(pAb)两种不同抗体双弹头标记物在肝癌患者体内的生物代谢情况。结果显示,两种抗体标记物的血浆清除半衰期均在24h左右,mAb标记物的清除较pAb标记物略慢。尿清除的半衰期,mAb标记物约为120h,而pAb标记物则约为18h,表明二者的体内生物代谢不同,疗效可能不一。  相似文献   
42.
人子宫内膜植入兔眼前房模型的研究   总被引:1,自引:0,他引:1  
本实验成功地将人子宫内膜植入到15只去卵巢新西兰雌兔的眼前房,并给每只兔外源补充雌二醇(E2)100μg/d和孕酮(P)8mg/d。在内膜植入期间每只兔皮下注射总量为9mg的霉酚酸(my-cophenolicacid)以防免疫排斥反应。在眼前房的人子宫内膜存活了28.44±8.65天,兔血清E2和P的平均值分别为161.71±15.13和38.88±7.45pmol/L。前房液中E2和P浓度在植入人子宫内膜前后分别为24.80±16.53和1709.25±475.10pmol/L,2.00±0.53和12.22±3.81nmol/L。树脂切片验证人子宫内膜植入兔眼前房第5天就能与虹膜附贴并有血管发生。来自巩膜的血管分布在子宫内膜周围。扫描电镜观察人子宫内膜分化成分泌细胞和纤毛细胞。植入人子宫内膜后,前房液的蛋白浓度高于植入前。可以证明该模型可用来研究人子宫内膜对药物的反应和通过对前房液的测量研究子宫内膜的分泌功能。  相似文献   
43.
Total global biodiversity is estimated at between 3 and 500 × 106 species of prokaryote and eukaryote organisms spread across 70 or more phyla. The marine macrofauna alone are estimated between 0.5 and 30 × 106 species and represents a broader range of taxonomic diversity than that found in the terrestrial environment, which has been the traditional source of natural products. With a typical eukaryote possessing 50,000 genes, the global marine macrofauna are the source of 2.5 × 1010 to 1.5 × 1012 primary products and an associated extensive range of secondary products. However, only a few thousand novel compounds from marine organisms have been described. These compounds have proven unique in chemical and pharmacological terms but, as yet, no therapeutic agents have resulted. Given a broader drug discovery strategy, and facilitated by technological advances, it is predicted that the characterisation of marine chemical diversity will be accelerated. Strategies for drug discovery from the virtually untapped chemical diversity of marine organisms are discussed. © 1994 Wiley-Less, Inc.  相似文献   
44.
1. In chloralose-urethane anaesthetized cats, the dorsal cardiovascular reactive area (DCRA) in the parvocellular reticular nucleus dorsomedial to the facial nucleus, and the ventral cardiovascular reactive area (VCRA) ventromedial to the facial nucleus, were stimulated by microinjections of sodium glutamate (100–200 nmol) or electric current. 2. Stimulation of DCRA, with a long latency of 15–20 s, elicited a marked increase of blood flow in the contralateral femoral artery with little change to moderate increase in systemic arterial blood pressure (ABP). In the relatively dorsal portion of DCRA, however, a smaller increase of blood flow in the ipsilateral femoral artery was elicited. 3. On the other hand, stimulation of VCRA with a short latency (3–5 s) evoked an increase of blood flow in both femoral arteries which was more prominent on the contralateral side. The responses were accompanied with decreases in the blood flow of other vascular beds with only a slight increase or minimal change in ABP. 4. The data suggest that DCRA and VCRA are both viscerotopically organized to alter the resistance of individual vascular beds for redistribution of blood flow.  相似文献   
45.
长泰乐生物保健口服液是一种新型腹泻治疗药物,用该药治疗感染性腹泻45例,与用氟哌酸治疗的对照组比较,结果表明疗效相近,且比后者使用安全。我们认为该药可代替抗生素用于治疗感染性腹泻轻、中型患者,尤其适用于老年、孕妇和儿童。对非感染性腹泻有良好的治疗前景。  相似文献   
46.
An avulsion fracture of the tibial tubercle is a common injury in traffic accident. If the fracture is closed, then a comparatively good prognosis can be expected through reinforcement of the bone via osteosynthesis and the use of artificial ligaments. In this case, an open wound was observed in the tibial tubercle, and the wound was so polluted that the healing process was significantly delayed. It was therefore difficult to provide simultaneous surgical treatment and so three operations were required to perform the reconstruction of the extensor mechanism. The reconstruction of extensor mechanism and the frame fixation between the patella and tibia was performed. Six months after the injury, the patient was able to walk without aid, had a range of movement from 5°to 130°, and did not show any indications of ADL disorder. Using this method of frame fixation between the patella and tibia proved to be an effective technique for the reconstruction of the open knee extension mechanism injury.  相似文献   
47.
Objective: To study the rapid effect of glucocorticoids (GCs) on NMDA receptor activity in hippocampal neurons in stress and to elucidate its underlying probable membrane mechanisms. Methods: Whole-cell patch-clamp recording was used to assess the effect of stress concentration corticosterone (B) on the responses of cultured hippocampal neurons to glutamate and NMDA (N-methy-D-asparatic acid). To make clear the target of B, intracellular dialysis of B(10μmol/L)through patch pipette and extracellular application of bovine serum albumin-conjugated corticosterone (B-BSA, 10μmol/L)were carried out to observe their influence on peak amplitude of NMDA-evoked current. Results: B had a rapid, reversible and inhibitory effect on peak amplitude of GLU-or NMDA-evoked current in cultured hippoeampal neurons. Furthermore, B-BSA had the inhibitory effect on INMDA as that of B, but intraeeUularly dialyzed B had no significant effect on INMDA. Conclusion: These results suggest that under the condition of stress, GCs may rapidly, negatively regulate excitatory synaptic receptors-glutamate receptors (GluRs), especially NMDA receptor (NMDAR) in central nervous system, which is mediated by rapid membrane mechanisms, but not by classical, genomic mechanisms.  相似文献   
48.
目的 :探讨胃癌组织中微血管密度 (MVD)与胃癌生物学行为的关系。方法 :应用免疫组织化学S -P法和抗人因子Ⅷ相关抗原 (FⅧ -RAg)的抗体 ,标记 6 8例胃癌组织中的微血管 ,检测MVD。分析其与胃癌组织学类型、分化水平、浸润深度及淋巴结转移的关系。结果 :6 8例胃癌组织中FⅧ -RAg阳性表达 5 2例 ,占 76 .4 7%。FⅧ -RAg和MVD与分化水平、浸润深度 (P <0 .0 1)及淋巴结转移 (P <0 .0 0 1)密切相关。不同组织学类型中FⅧ-RAg的表达具有显著相关性 (P <0 .0 1) ,而MVD则与胃癌组织学类型无显著差异 (P >0 .0 5 )。 结论 :血管生成对胃癌的发展具有一定作用 ,FⅧ -RAg的检测和MVD可作为判断胃癌恶性程度和预后的生物学指标。  相似文献   
49.
Patientsfeelimpatientbecausetheycouldnotpredicttheonsettimeofepilepsy.Ifonsettimeofepilepsycouldbepreciselypredicted,thendrugadministrationanddisabilityofpreventionwillbecomeavailable.In1879,Echevarrzafoundonsettimeofepilepsyisdistributedaccordingtosomerules.Inrecentyears,scientistsperformalotstudiesinvolvingcytologyandmolecularbiologyofepilepsy.Clinicaldataindicatedonsetofepilepsyhascloserelationwithbiologicalrhythmsuchasawakeandsleepcycleandmenstrualcycle.Theobjectiveofthisstudy…  相似文献   
50.
S P Caudill  S J Smith  G R Cooper 《Statistics in medicine》1989,8(3):295-309; discussion 331-2
Using data from the National Health and Nutrition Examination Survey (NHANES II) 1976-1980, we demonstrate how cross-sectional total serum cholesterol surveillance data can be used by an individual to assess current and future personal cholesterol risk status. We propose statistical models, based on a person's current measured cholesterol level and the relationship between cross-sectional age and cholesterol percentile estimates, that will allow prediction of future cholesterol levels or the age at which specified cholesterol risk levels will be reached if no cholesterol-altering intervention is taken. These models incorporate the observed variation in the NHANES II data and expected intraperson biological variation and intralaboratory analytical variation. We illustrate the adequacy of the models using data from the longitudinal Framingham Study.  相似文献   
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