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81.
Objective: The objective of this study was to determine whether human papillomavirus (HPV) infections are involved in the development of papillomatosis lesions of the lower female genital tract.Methods: A total of 616 biopsy specimens of genital papillomatous lesions (307 nodular and 309 papular types) from 598 patients were anaylyzed for the presence of HPV DNA sequences by polymerase chain reaction (PCR). These specimens were also examined by histopathological assessment for characteristic HPV-associated cytological changes, by immunohistochemical staining for HPV-associated antigen, and by electron microscopy for the presence of virions.Results: HPV DNA sequences were found in 97.9% (140 of 143 cases) and 1.1% (1 of 91 cases) of the nodular and papular papillomatosis cases tested, respectively. In 18 patients who had both types of papillomatosis lesions, HPV DNA was invariably found only in nodular tissues. HPV-associated antigen, koilocytosis, and virions were found in 53.6% (98 of 183 cases), 70.5% (129 of 183 cases), and 5.9% (5 of 85 cases) of nodular papillomatosis lesions tested, respectively.Conclusions: These data suggest that nodular papillomatosis was closely associated with HPV infection, but that papular papillomatosis of the lower female genital tract may have an etiology other than HPV infection.  相似文献   
82.
Kaur C  Ling EA 《Neuroscience letters》1999,262(3):183-186
This study was aimed to ascertain the effects of hypoxia on regulation of iron in the brain of newborn rats. At 3 h and 1 day after hypoxic exposure transferrin receptor expression as detected immunohistochemically with the antibody OX-26, and the iron content as shown by Perls' staining of amoeboid microglial cells was markedly increased. The induced changes, however, were not evident at 10 min and in longer surviving rats killed at 3 and 7 days. It is suggested that the upregulation of transferrin receptor expression coupled with iron uptake by amoeboid microglial cells in the periventricular regions is a protective mechanism to facilitate the sequestration of excess iron that may have been released either from the iron-rich oligodendrocytes, or accumulated due to a disruption of its normal transportation following the hypoxic insult. This would help protect the brain from harmful effects of iron.  相似文献   
83.
OBJECTIVES: To compare the effects of the soft cushion setting with those of the hard cushion setting of a Biodex II isokinetic dynamometer on peak velocity and peak torque with six loads at 23 preset speeds. DESIGN: Mixed within- and between-groups, repeated-measures design. SETTING: Research laboratory of a physical therapy education program. INTERVENTIONS: Each load was strapped onto the right knee attachment of the dynamometer and was dropped through a 100 degrees arc of motion five times at each preset speed using the soft and hard cushion settings. MAIN OUTCOME MEASURES: Peak velocity, peak torque, time to peak velocity, time to peak torque. RESULTS: Peak velocity was significantly influenced by the cushion setting, the weight dropped, and the preset speed. Maximal peak velocity achieved was 400 degrees/sec. Peak torque was influenced significantly by the cushion setting, the load, and the preset speed. Maximal peak torque measured was 34.99 kg-m. CONCLUSION: The rotating shaft of Biodex II dynamometer moved at a slower speed through the entire arc of motion at the soft cushion setting and often failed to achieve a constant, preset speed. Peak torque measured using the soft cushion setting was more variable and therefore questionable.  相似文献   
84.
Pramipexole (PPX) is a full intrinsic activity, direct-acting dopamine (DA) agonist possessing 7-fold higher affinity for D3 than for D2 receptors. It also is a potent antioxidant. PPX was previously shown to be neuroprotective because it dose dependently attenuated the DA neuron loss produced by levodopa in mesencephalic cultures. Several different drugs with properties similar to PPX were studied here to better understand the mechanism or mechanisms responsible for this neuroprotective effect. The D3-preferring agonist 7-hydroxy-diphenylaminotetralin (7-OH-DPAT) and the D3 antagonist U99194, respectively, increased and decreased the neuroprotective effects of PPX in a dose-dependent fashion. Addition of the selective D2 agonist U95666 or the D2/D3 antagonists domperidone or raclopride did not affect PPX's neuroprotective effect. Interestingly, 7-OH-DPAT by itself did not attenuate the DA neuron loss produced by levodopa. However, when 7-OH-DPAT was combined with a low dose of the antioxidants U101033E or alpha-tocopherol, the toxic effects of levodopa were attenuated. Similar results were observed when the D3-preferring agonist PD128, 907 was studied. In addition, media conditioned by exposure of mesencephalic cultures incubated with all D3-preferring agonists studied was shown to enhance the growth of DA neurons in freshly harvested recipient cultures implicating a D3-mediated trophic activity in the neuroprotective effect. These data suggest that PPX's neuroprotective actions in the levodopa toxicity model are a consequence of its combined actions as a D3 receptor agonist and an antioxidant.  相似文献   
85.
蝶腭,筛前神经及鼻甲联合手术治疗常年性变应性鼻炎   总被引:1,自引:0,他引:1  
在鼻内窥镜下为40例行蝶腭、筛前神经及鼻甲联合手术治疗常年性变应性鼻炎。结果:术后1月全部患者症状消失,显效100%;术后1年显效33例,占82.5%;有效6例,占15%,有效率为97.5%。提示该方法可广泛阻滞鼻腔副交感神经来源,降低鼻粘膜感觉灵敏部位敏感性以及感觉—副交感神经反射,破坏喷嚏反射弧的传入通路,使鼻粘膜对外界刺激敏感性下降,血管扩张减轻,腺体分泌减少,对常年性变应性鼻炎有明显疗效。  相似文献   
86.
目的 :ABO亚型在临床输血中经常造成错定血型及输血反应 ,因而研制抗A1试剂血清是解决ABO亚型鉴定的主要途径。方法 :采用血型血清学特异性抗原抗体吸收实验。结果 :经大量反复实验 ,研制出特异性强 ,效价符合要求的抗A1试剂血清。结论 :抗A1血清是鉴定A亚型的专用试剂血清 ,对临床鉴定ABO亚型及安全输血有实用意义。  相似文献   
87.
评价低温保存板层角膜移植材料的效果。方法将15只人尸角膜分三组保存2年:4℃甘油脱水法,角膜液氮冷冻法,全眼球液氮冷冻法。并做透射电镜观察。结果第一组中,角膜胶原纤维排列紊乱,疏松,缺乏连续性,可见广纤维变性,纤维间可见极低电子密度灶。  相似文献   
88.
The influence of operative technique on the formation of incomplete cement mantles in the sagittal plane has been rarely considered in the literature. In this article, we discuss the influence of the anatomy of the proximal femur on the formation of incomplete cement mantles and discuss how their incidence can be reduced by correct component positioning.  相似文献   
89.
Disorders of pyruvate carboxylase and the pyruvate dehydrogenase complex   总被引:3,自引:0,他引:3  
Summary The most common defect associated with deficiency of the pyruvate dehydrogenase (PDH) complex occurs in the E1 component, specifically due to mutations in the X-linked E1 gene. Clinical sequelae of these mutations, which range from severe neonatal lactic acidosis to carbohydrate-sensitive ataxia, can be different in males and females depending on the nature of the mutation and, in the case of females, on the X-inactivation pattern in different tissues. Males have a high representation of missense mutations among the patient cohort, while females are much more likely to have DNA rearrangements, particularly toward the 3 end of the coding sequence of the gene. Missplicing mutations involving exon 6 deletion have been reported, as has a missense mutation conferring true thiamin-responsiveness of the enzyme and the patient's clinical symptoms.Pyruvate carboxylase deficiency, on the other hand, is a true autosomal recessive disease, though it has high occurrences in particular ethnic groups, especially in Algonkian-speaking Amerindians and in Arabs. In the former group the defect is a simple type in which material cross-reactive to pyruvate carboxylase antibody is present in cultured cells (CRM+ve). In the latter group, cross-reacting material is rarely present (CRM–ve). The CRM+ve patients can survive into teenage years with careful supervision, while the CRM–ve patients have complications due to hyperammonaemia and dysfunction of the urea cycle and rarely survive beyond 3 months of life.  相似文献   
90.
  • 1 Angiotensin II (AngII)-induced, activation of phospholipase C (PLC) and Ca2+-dependent Cl? channels is an important signal transduction pathway for the regulation of vascular smooth muscle cell (VSMC) and glomerular mesangial cell contraction and growth. While AT receptors are traditionally thought to be G-protein coupled to the β isoform of PLC, recent evidence suggests that in some tissues AT receptors may also activate the PLC-γ isoform via tyrosine phosphorylation.
  • 2 By western analysis, we identified PLC-γ1 in the above cell types. We found that within 3 min of exposure to 10?7 mol/L AngII, tyrosine phosphorylation of PLC-γ1 was observed; however, peak response (> 3-fold increase) occurred within 0.5 min. In addition, pre-incubation of these cells with the tyrosine kinase inhibitor genistein blocked the tyrosine phosphorylation of PLC-γ1 by AngII. In contrast, preincubation with the tyrosine phosphatase inhibitor sodium vanadate increased the levels of tyrosine phosphorylation of PLC-γ1. Similar results were found when intracellular levels of 1,4,5-IP3 were measured after AngII exposure.
  • 3 By using patch clamp techniques on cultured rat mesangial cells exposed to AngII, we found that the release of 1,4,5-IP3-sensitive intracellular Ca2+ stores stimulated low conductance Cl? channels. Preincubation with genistein, abolished the usual 10-fold increase in Cl? channel activity observed with AngII.
  • 4 Therefore, we conclude that in VSMC and glomerular mesangial cells (i) AngII transiently stimulates PLC activity via tyrosine phosphorylation of the γ1 isoenzyme, (ii) tyrosine phosphorylation of PLC-γ1 and production of 1,4,5-IP3 in response to AngII is dramatically inhibited by tyrosine kinase inhibition and stimulated by tyrosine phosphatase inhibition, (iii) activation of Ca2+-dependent Cl? channels by AngII-induced release of 1,4,5-IP3-dependent intracellular Ca2+ stores is also abolished by tyrosine kinase inhibition. In summary, this AngII-induced signal transduction cascade provides a possible mechanism for both the contractile and growth-stimulating effects of AngII on VSMC and glomerular mesangial cells.
  相似文献   
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