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81.
反复自然流产患者血清中封闭抗体的检测 总被引:5,自引:2,他引:5
本文根据病史将反复自然流产(RSA)分类为原发性RSA 及继发性RSA,分别以单向混合淋巴细胞反应封闭试验及补体依赖微量细胞毒试验评价封闭抗体与两类流产的关系。结果发现,原发性RSA主要因封闭抗体缺乏所致;而继发性RSA 无封闭抗体缺乏迹象。因此,尽管原发性RSA 与继发性RSA 临床表现类似,但其免疫学病因及发病机理可能不同。 相似文献
82.
目的 了解血清涎液化糖链抗原(KL-6)在常见结缔组织病(CTD)并发肺间质病变(ILD)患者中的表达水平及其临床意义。方法 选取2021年4~11月蚌埠医学院第一附属医院收治的187例CTD患者为研究对象,按照结缔组织病有无肺间质病变分为结缔组织病并发肺间质病变(CTD-ILD)组116例,结缔组织病无肺间质病变(CTD-NILD)组71例;选取41例同期本院体检健康者为对照组。在CTD-ILD组中,根据肺高分辨CT(HRCT)表现分为急性组和慢性组;根据HRCT显示的ILD累及范围进行分级(1级,累及范围≤25%;2级,25%<累及范围≤50%;3级,50%<累及范围≤75%;4级,75%<累及范围≤100%);随后根据CTD-ILD患者是否合并有肺部感染分为有肺部感染组和无肺部感染组。采用乳胶凝集法测定血清KL-6水平,比较不同分组血清KL-6水平差异。结果 CTD-ILD组血清KL-6水平高于CTD-NILD组和对照组,差异有统计学意义(P<0.05)。CTD-ILD患者血清KL-6水平在急性组高于慢性组(P<0.05),在有肺部感染组和无肺部感染... 相似文献
83.
左旋氧氟沙星口服后在肝硬化患者血清和腹水中分布及其对并发细菌性腹膜炎的疗效 总被引:3,自引:1,他引:2
目的 :研究左旋氧氟沙星口服后在肝硬化患者血清和腹水中的分布及动态变化 ,评价该药对肝硬化并发原发性细菌性腹膜炎 (SBP)的疗效。方法 :收集 7例肝硬化合并腹水患者口服左旋氧氟沙星 30 0 m g后不同时间点的血清 (0 .5、1、1.5、2、12 h)和腹水 (2、4、6、12 h)标本 ,采用高效液相法检测其中药物浓度并观察其动态变化 ;对 30例肝硬化并发 SBP患者予左旋氧氟沙星 30 0 mg口服 ,2次 / d,连续 7~ 14d,进行疗效评价。结果 :各个时间点的血清和腹水标本中均可测出药物浓度并随给药时间呈动态变化 ,血清中达高峰浓度时间 tmax约 1.5 h,高峰浓度 cmax(3.913± 1.388)μg/ m l,腹水中 tmax约 6 h迟于血清 ,cmax(2 .5 2 0± 1.2 13)μg/ m l,低于血清。血清和腹水中药物浓度达到高峰后随时间推移而逐渐下降 ,至 12 h两者趋于稳定。并发 SBP患者经治疗后发热、腹部体征、腹水性状和外周血象均有明显改善 ,未见明显药物毒性及不良反应。结论 :左旋氧氟沙星口服后在患者的血清和腹水中均有分布并可形成高峰浓度 ,有效药物浓度持续时间长达 12 h以上 ;治疗 SBP特别是对轻中度患者疗效明显 ,并具有口服吸收好、给药次数少、无明显毒性及不良反应的优点。 相似文献
84.
85.
目的 探索遗传性进行性无综合征耳聋患者的听功能改变特点。方法 一个常染色体显性遗传进行性无综合征耳聋家系 5 2名成员及听力正常组 15名 ,进行了纯音测试及畸变产物耳声发射 (distortionproductotoacousticemissions,DPOAE)测试。结果 无综合征耳聋家系中 34名成员纯音测试为感音神经性聋 ,其中纯音听阈均值 (puretoneaverage ,PTA)≥ 40dB的 15例 (2 9耳 )DPOAE反应缺失 ,PTA≤ 35dB伴高频下降的 12例 (2 3耳 )DPOAE高频或高、中频振幅下降或缺失 ;2 1名 (42耳 )纯音听阈正常成员中 ,有 12例 (15耳 )DPOAE高频或高、中频振幅下降或缺失。结论 DPOAE能鉴别出耳蜗亚临床的病理改变 ,对该病的早期诊断 ,遗传咨询有指导意义。 相似文献
86.
Kwak JY Beer AE Kim SH Mantouvalos HP 《American journal of reproductive immunology (New York, N.Y. : 1989)》1999,41(1):91-98
PROBLEM: Placental lesions of 71 women with documented recurrent spontaneous abortions of unknown etiology were evaluated using immunohistochemical staining. METHOD OF STUDY: Placental tissue blocks (less than 12 weeks gestation) from prior pregnancy losses were obtained, recut, and analyzed utilizing monoclonal antibody to identify the trophoblast (cytokeratin 8/18) and natural killer (NK) cells (CD57) at the implantation site. The following features were evaluated: trophoblast invasion pattern; syncytium formation; vasculitis and thromboembolism of decidual vessels; decidual inflammation; decidual necrosis; fibrin deposition at the decidual necrosis site; mononuclear-cell infiltration in villi and intervillous space; perivillous fibrin deposition; trophoblast morphology; and quantitation of CD57+ NK cells within the decidual tissue near the implantation site. Controls consisted of 20 healthy women with no history of recurrent pregnancy losses, who had their pregnancies electively terminated. RESULTS: Of the women studied, 29.6% demonstrated elevated CD57+ NK cells at the implantation site (P = 0.030), 54.1% had inadequate cytotrophoblast invasion depth (P = 0.000), 44.1% demonstrated inadequate syncytium formation (P = 0.004), and 33.9% presented thromboembolism in decidual vessels (P = 0.025). CONCLUSION: Some women with recurrent spontaneous abortions demonstrate abnormal placental lesions at the implantation site. Immunopathologic evaluation of the placental implantation site that terminated in a spontaneous abortion may reveal the immunopathogenesis of previous pregnancy losses. 相似文献
87.
人参根及茎叶皂苷 50~200 mg/kg能使群养小鼠的自发运动量明显增加,8周隔离饲育小鼠比群养小鼠自发运动量明显增加,人参根皂苷能使其剂量依赖性降低,而人参茎叶皂苷影响不明显;对戊巴比妥钠所致睡眠试验中,隔离孤独饲育小鼠比群养小鼠睡眠时间明显缩短(t=4.356,P<0.001)。人参根皂苷 50~200 mg/kg使孤独饲育小鼠的睡眠时间随剂量增加而延长,200 mg/kg组与对照组比较,t=3. 665,P<0.01。并能使 8周隔离饲育的小鼠 20 min内连续攻击时间有意义地下降(t=4.540,P=0.001),但人参茎叶皂苷效果不明显。证明人参根及茎叶皂苷具有中枢兴奋作用,同时人参根皂苷还具有中枢镇静作用。 相似文献
88.
Cartling B 《Behavioural brain research》1999,100(1-2):255-271
Mechanisms underlying and controlling resolution and perception in working memory are studied by means of a pulse-coupled network model. It is shown that the adaptivity, i.e. the degree to which previous activity affects the ability to fire, of the excitatory units can control several aspects of the network dynamics in a coordinated way to enable multiple items to be resolved and perceived in working memory. One basic aspect is the complexity of the dynamics that regulates the temporal resolution of several items. The slow NMDA-receptor-mediated component of synaptic couplings to excitatory units facilitates successive activations of a given item. The dimension of the activated subspace of the complete available neural representation space is gradually decreased as adaptivity is reduced. It is also shown that the formation of perception by sufficiently intense and coherent activation of different features of an object can be controlled concurrently with resolution by the adaptivity. The mechanisms derived can account for the observed capacity of working memory with respect to number of items consciously resolved and also for the observed temporal separation of different items. Numerous observations link neuromodulators to cognitive functions and to various brain disorders involving working memory. Based on the influence of various neuromodulators on neuronal adaptivity, the model can also account for neuromodulatory regulation of working memory functions. 相似文献
89.
H. Özbey C. Boneval Ü. Alkaç B. Bavbek G. Çakiroğlu T. Salman A. Çelik 《Pediatric surgery international》1996,11(8):547-549
It is known that polycythemia decreases the fluidity of the blood and impairs tissue perfusion due to red-cell sludging in the microcirculation. In this study, the effect of polycythemic hyperviscosity (PH) on bowel necrosis was evaluated in an experimental model of intestinal ischemia. Twenty-eight Wistar albino rats (90–170 g) were divided into two groups: group 1 was transfused to create hyperviscosity and then intestinal ischemia was produced (n = 16); in group 2 ischemia was produced without transfusion (n = 12). Intestinal ischemia was produced by clamping the superior mesenteric artery and the collateral arcades of the right colic artery for 30 min. Gross and histopathologic evaluations were performed by either immediate necropsy or relaparotomy 24 h later. Microscopic findings were graded from 0 to 3 according to the degree of ischemic changes. In group 1, 2 animals (12.5%) died before 24 h postoperatively; coagulation necrosis with grade 2 or 3 ischemic changes was observed in 10 animals (62.5%). In group 2 only a few hypertrophied Peyer's patches and capillary dilation were found, and all histopathologic changes were between grades 0 and 1. The difference between the histopathologic gradings of the two groups was significant (P < 0.001). It appears that in addition to reduced splanchnic blood flow, a secondary effect of PH is needed to induce ischemic coagulation necrosis. PH of the newborn must be considered a risk factor for necrotizing enterocolitis, so-called spontaneous intestinal perforations, and even intestinal atresia.Presented at the 1st European Congress of Pediatric Surgery, Graz/Austria, May 4–6, 1995 相似文献
90.
Korhonen J.; Tiitinen A.; Alfthan H.; Ylostalo P.; Stenman U.-H. 《Human reproduction (Oxford, England)》1996,11(12):2750-2757
We studied the dynamics of serum human chorionic gonadotrophin(HCG) and its free (HCG) and (HCGP) subunits in 49 early pregnanciesachieved by in-vitro fertilization (IVF) and embryo transfer.Of the 49 early pregnancies, nine were normal singleton pregnancies,11 were twin pregnancies, 11 were ectopic, eight ended in aclinical (spontaneous) abortion and 10 ended in a preclinicalabortion. The HCG, HCGa and HCGP concentrations in serum weremeasured on days 12, 19 and 26 after embryo transfer. Most ectopicpregnancies could be distinguished from singleton (and twin)pregnancies on the basis of low HCG concentrations by 12 daysafter embryo transfer, but clinical abortions could not be distinguishedfrom singleton pregnancies. In general, the measurement of HCGaand HCG and the molar ratios of the various forms provided onlymarginal additional value to that obtained from HCG, but ondays 19 and 26 after embryo transfer HCGa was the most sensitiveindicator of a normal pregnancy after IVF and embryo transfer.We conclude that in ectopic pregnancies the concentrations ofHCG, HCGa and HCGP increase as expected but 1.5 days later thanin normal pregnancies. This appears to be the result of a delayin implantation. 相似文献