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81.
目的 探讨主动吸入药物烟对大鼠NO的影响。方法 制备大鼠主动吸烟模型 ,采用硝酸还原酶法测定各组大鼠血清、肺、心肌及脑组织的NO含量。结果 非药物烟组大鼠血清、肺、心肌及脑组织中NO含量明显低于非给烟对照组 ,药物烟高、中剂量组NO含量明显高于非药物烟组 ,接近非给烟对照组。结论 吸烟对大鼠血液、肺、心肌及脑组织有不同程度的损伤作用 ,使NO含量降低 ;药物烟具有一定的保护和防止NO含量降低的作用。  相似文献   
82.
The in vitro DNA amplification technique of polymerase chain reaction was used to evaluate the possible presence of human papillomavirus (HPV) in small cell carcinoma of the uterine cervix. None of the 12 cases examined contain detectable amounts of either HPV type 16, 18, 31, or 33 DNA. On the other hand, HPV types 16 and 18 DNA were found in 14 (93.3%) and 9 (60.0%) of 25 invasive cervical squamous carcinoma tissues. The results seem to suggest that these types of HPV are not present or are present in extremely small quantities in cervical small cell carcinoma. Such an absence of HPV DNA makes it unlikely that these types of HPV play any etiological role in the pathogenesis of cervical small cell carcinoma.  相似文献   
83.
目的 观察急性脑梗死 (ACI)后血浆一氧化氮 (NO)、一氧化氮合成酶 (NOS)、内皮素 (ET)含量的动态变化 ,以及尼莫地平治疗后对其影响。方法 ACI患者 110例 ,随机分成尼莫地平组 (5 0例 ) (在常规治疗基础上用尼莫地平 )和常规治疗组 (6 0例 )。在发病后不同时点动态观察血浆NO、NOS、ET含量 ,并设 5 0例脑动脉硬化患者为对照组。结果 脑梗死后血浆ET含量显著升高 ,直至恢复期 ;NO、NOS先增高后下降 ;尼莫地平组和常规组比较ET有显著差异 (P <0 .0 1) ,NO、NOS差别不显著 (P >0 .0 5 )。结论 NO、NOS、ET参与并影响了ACI后复杂的病理生理过程 ;尼莫地平部分通过对ET含量的影响发挥其对脑梗死的治疗作用  相似文献   
84.
The purpose of this study was to determine the nature and amounts of prostaglandins (PGs) produced by squamous carcinoma cells (SCC) and the sensitivity of these cells to non-steroidal anti-inflammatory drugs. SCC of four lines of the tongue and one line of facial epidermis of humans were incubated in phosphate buffer solution with 14C-arachidonic acid (AA). Radioactive metabolites in aqueous methanol were chromatographed on Sep-Pack CIS cartridges, separated and quantitated by means of TLC, autoradiography, and liquid scintillation counting. The results showed that cyclooxygenase products, PGs, were the major products formed by all cell lines, and PGE2 was predominant among the PGs detected. Two radioactive bands corresponding to PGF and three unseparated standards of PGA2, 15-keto-PGE2, and 13,14-dihydro-15-keto-PGE2were detected in lesser amounts. Very small amounts of the lipoxygenase products 12-and 15-HETE were found. The concentrations of indomethacin, ibuprofen and aspirin required to inhibit 50% of PGE2 synthesis (IC50) by SCC lines were .008- .080, .080–6.4 and 32–88 μM, respectively.  相似文献   
85.
本调查是对××冶炼厂227名接铅工人作了尿铅、尿中δ-ALA、尿粪卟啉及末梢血中碱粒红细胞的测定,同时与对照组进行了比较。结果表明:(1)接铅工人尿中δ-ALA检出均高出非接铅健康工人,且差别非常显著。(2)随着接铅工龄的增加,工人尿中δ-ALA的超标率也相应的增多。(3)接铅工人尿中δ-ALA的变化比CP要早,对铅的接触更敏感。(4)尿中δ-ALA与尿铅呈明显相关,而与碱粒红细胞相关不明显。  相似文献   
86.
The multitest CMI system, a disposable device that simultaneously applies seven standardized preloaded antigens and diluent control, is a major advance for measurement of delayed type hypersensitivity (DTH) in assessment of cell-mediated immunity (CMI). The system was tested in 84 healthy volunteers, 42 in each sex, aged 4-62 years, to determine normal values for incidence and size of DTH responses to each of seven antigens. Incidence of positive responses to individual antigens varied from 84.5% to 11%, more than half of volunteers were reactive to Tuberculin, Candida and Diphtheria, and a third to Tetanus, Streptococcus and Tricophyton. 95.3% of volunteers to one or more antigens, and about two thirds to three or more. To better assess CMI, a two-part score based on 48-hour readings was employed. The mean number of positive antigens ranged between 2.2 and 3.3, the mean sum of their millimeter induration ranged between 10.8 and 18.2, the average sum of diameters were 16.7 mm in males and 15.2 mm in females. There was no statistic significance to sex and age during scoring, although there was somewhat higher in males, young and mature age groups. In our series, Tuberculin reaction is the highest one in this seven antigens, about 4.76% of volunteers are anergy. A statistical zone (95% confidence limits) of reduced DTH scores (hypoergy) was identified, it reveals sum of diameters less than 9mm in males and 7mm in females, number of positive antigens are less than 2 in each sex.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
87.
[目的]探讨不同起搏模式对病人生存质量(QOL)的影响。[方法]以健康调查问卷(SF一36量表)对112例不同起搏模式病人进行问卷调查,比较3种起搏模式下病人的QOL水平。[结果]除机体疼痛、角色情绪2个维度外其余6个维度(生理功能、角色限制、活力、社会功能、精神健康、总体健康)3种起搏模式间比较差异有统计学意义(P〈0.05)。[结论]应用AAI型、DDD型起搏器的病人生存质量优于VVI型起搏。  相似文献   
88.
目的 探讨^99mTC-MIBI动态显像对非小细胞肺癌化疗疗效的预测价值。方法 对确诊为不能手术的非小细胞肺癌患者化疗前,静脉注射740mbq ^99mTC-MIBI后分别于30min,2h行SPECT动态扫描,计算早期/晚期肿瘤组织与对侧正常肺组织的放射活性比(T/Ne,T/Nd),全身采用卡铂/顺铂+VP16化疗3周期,随后复查胸部CT,评判化疗疗效及其与^99mTC-MIBI动态显像的关系。结果 78例NSCLC符合入选标准,并完成化疗方案,66例呈阳性显像,12例阴性显像,66例阳性显像中化疗有效率为90.7%,阴性显像12例中化疗全部进展,两者比较差异有显著性(P〈0.01)。结论 ^99mTC-MIBI动态显像的放射活性越高,化疗效果越好,对非小细胞肺癌化疗疗效有预测价值,可为合理制定治疗方案提供重要依据。  相似文献   
89.
超声对宫角妊娠的诊断及治疗意义   总被引:5,自引:0,他引:5  
杨新  柳建华等 《医学文选》2002,21(4):444-446
目的 探讨对误诊率高,危害大的罕见特殊部位宫角妊娠的诊断和治疗。方法 对我院1991-2001年收治的宫角妊娠临床资料进行回顾性分析。结果 宫角妊娠17例中误诊宫内妊娠行人流失败4例。13例行腹部手术,3例行B超监视下人流术,1例行子宫动脉栓塞术。结论 宫角妊娠临床诊断困难,误诊率高,破裂后造成迅猛的腹腔内出血,应提高对少见部位宫角妊娠的认识,减少孕妇死亡。  相似文献   
90.
Effects of stimulation of brainstem sites on hemodynamics and plasma catecholamine levels were assessed in cats under chloralose-urethane anesthesia. Pressor areas of the dorsal medulla (DM) and ventrolateral medulla (VLM) and the depressor area of the paramedian reticular nucleus (PRN) were stimulated electrically using a monopolar electrode, or chemically using sodium glutamate microinjection. Plasma levels of norepinephrine (NE) and epinephrine (EPI) were measured in caval blood above the adrenal veins. Electrical stimulation of the DM and VLM produced increases in blood pressure and in plasma NE and EPI levels that were enhanced after acute vagotomies. The NE and EPI responses were attenuated after acute, bilateral adrenalectomies, confirming augmented adrenomedullary secretion, whereas the pressor responses were intact. Injection of sodium glutamate into the same pressor regions of the DM or VLM also produced pressor responses and elevated plasma catecholamine levels, indicating that the responses resulted from activation of neuronal perikarya. Stimulation of the PRN attenuated pressor and catecholamine responses during stimulation of the DM and VLM. The results indicate that pressor responses during stimulation of the DM and VLM are due at least partly to activation of perikarya in these regions, are associated with but not dependent on adrenomedullary activation, and are enhanced after vagotomy; and that neurons of the PRN exert inhibitory modulation of the pressor and adrenomedullary responses during stimulation of VLM and DM.  相似文献   
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