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31.
目的 判定增龄对皮肤血流量的影响。方法 用PIM2-LDPI检测皮肤血流量。结果 老年组前额、左手指背、命门穴部位皮肤血流量分别为:(1.94±0.86)V,(1.92±0.52)V和(0.71±0.19)V,与青年组比较差异无显著性。但是,老年男性在命门穴的皮肤血流量明显高于青年男性(P<0.05),老年女性前额的皮肤血流量明显降低(P<0.01)。男性比女性的皮肤血流量高。结论 皮肤血流量的差异无年龄相关性,男性组的皮肤血流量比女性组高。  相似文献   
32.
目的探讨外周高渗刺激激活下丘脑室旁核(PVN)神经元的细胞类别。方法以腹腔注射高渗盐水作为外周高渗刺激。细胞外记录PVN神经元单位放电的变化,并用免疫细胞化学方法观察PVN中los的表达及los表达阳性神经元的性质。结果腹腔注射高渗盐水使PVN的位相型放电神经元兴奋,PVN内los表达明显增加,特别是PVN大细胞中大量的los阳性神经元同时表达精氨酸加压索(AVP)。结论外周高渗刺激能够激活PVN内的加压索(VP)能神经元。  相似文献   
33.
诱导型一氧化氮合酶在前列腺增生组织中表达的研究   总被引:1,自引:0,他引:1  
目的:探讨诱导型一氧化氮合酶(iNOS)与前列腺增生(BPH)病理生理变化的关系。方法:用免疫组化法检测10例正常和30例有膀胱出口梗阻的BPH患者膀胱和前列腺组织中iNOS的表达。结果:BPH组前列腺组织中iNOS呈阳性染色,主要分布于前列腺的上皮细胞及上皮下组织中,间质平滑肌组织中均为阴性;对照组的膀胱壁、膀胱颈部和前列腺组织中均无iNOS阳性染色。结论:iNOS仅在BPH患者前列腺组织中有特异性表达,提示它参与了前列腺增生的病理生理过程。  相似文献   
34.
Objective: To summarize the clinical outcomes of 117 human vitrified blastocyst transfer cycles and to determine the impact factors.Methods: In IVF-ET cycles, supernumerary embryos were cultured to 5-Day(D5) or 6-Day(D6), blastocysts of various stages were cryopreserved by vitrification using cryoloops. Survival rate and clinical pregnancy rate were observed.Results: A total of 312 blastocysts were thawed in 117 frozen embryo transfer cycles, the survival rate was 90.7% (283/312) after thawing. After the transfer of 230 blastocysts in 115 cycles, 69.6% (80/115) of the women got clinically pregnant, and 17.5% (14/80) of them suffered from miscarriage, 39 healthy babies were born in 28 deliveries, and the other 38 pregnancies are ongoing. The implantation rate was 47.4% (109/230). In 107 transfer cycles with 2 hatched blastocysts transferred in each cycle, 72.9% (78/107) got clinically pregnant, while in 8 cycles with 1 or no hatched blastocysts in the two transferred blastocysts, the clinical pregnancy rate is 25%(2/8). The clinical pregnancy rates were not statistically different between natural (77.4%, 24/31) or artificial endometrium preparation (66.7%, 56/84) cycles. Conclusions: These findings suggest that blastocyst vitrification is effective in terms of implantation rate and pregnancy outcome. Transferring of two hatched blastocyst can achieve a higher pregnancy rate.  相似文献   
35.
准分子激光角膜切削术治疗近视的并发症   总被引:3,自引:0,他引:3  
为分析准分子激光角膜切削术(PRK)治疗近视的并发症,对139例(257眼)PRK术后随访半年至一年。结果表明:术后一年,低中度和高度组各有1眼最佳矫正视力丢失二行,分别占2.5%和3.3%;低中度和高度组的角膜上皮下1级混浊分别为10.81%和15.16%,2级混浊分别为2.73%和0%;激素性高眼压,在发生率最高的3个月时,可分别达24.37%和25.32%,但这种反应性的眼压升高只是暂时的,容易控制;过矫和散光增加的发生率均较低,主要与术者的经验有关。随着术者经验的提高、手术设计的完善及术后用药的研究,这些并发症会降到最低水平。PRK是安全、有效的。  相似文献   
36.
采用连续流动反应装置,考察了裂解汽油在HZSM-5与金属元素改性的HZSM-5上的芳构化反应,发现锌改性后提高了液体产物中芳烃的收率。为了克服裂解汽油中含硫含焦杂质的影响,提出了获取芳烃的有效工艺:蒸馏除焦-加氢预脱硫-氢气氛下芳构化反应-冷凝产物。用氨吸附的程序升温脱附法,将催化剂的酸性质与其催化芳构化作用进行关联,认为Zn改性后的HZSM-5催化剂具有较温和的酸中心,可能是其芳构化高活性与高选择性的原因。  相似文献   
37.
Spectral slope of vowels produced by tracheoesophageal speakers   总被引:1,自引:0,他引:1  
Spectra of vowels were analyzed to determine whether differences exist between the spectral slope of vowels produced by tracheoesophageal (TE) speakers and normal speakers and, if so, to quantify such differences. The linear predictive autocorrelation method was used to calculate smoothed spectra and the spectra were normalized with respect to a low frequency component. Comparisons between normalized spectral energy within a selected high frequency range revealed that energy within this frequency range for vowels produced by TE speakers was significantly higher than that produced by normal speakers. A least-square distance matching procedure was used to quantify speaker group differences in the spectral slope of vowels. Average spectra of vowels produced by the normal speakers could be matched to average spectra of vowels produced by the TE speakers by decreasing the spectral slope of their vowels by 2-3 dB/octave.  相似文献   
38.
本文应用“冷沉淀”法制备纤维组织粘合剂。对纤维组织粘合剂中主要成份和含量进行了测定,并测定了主要理化性质,建立了动物实验模型,观察了实验兔对纤维粘合剂的反应。  相似文献   
39.
用平板沉降法测定驻广州部队营区春季大气微生物含量。结果表明,营区大气微生物含量较高(10 311CFU/m~3)。驻市区部队营区大气微生物含量高于近郊营区,建议加强环境卫生监督、监测,控制环境污染。  相似文献   
40.
Nuclear factor-kappaB (NF-kappaB) plays a key role in inflammation, which is involved in the development of cerebral vasospasm after subarachnoid hemorrhage (SAH). In the present study, we assessed the potential role of NF-kappaB in regulation of cerebral vasospasm. Nuclear factor-kappaB DNA-binding activity was measured in cultured vascular smooth muscle cells (VSMCs) treated with hemolysate and pyrrolidine dithiocarbamate (PDTC, 80 micromol/L), an inhibitor of NF-kappaB. Forty-two rabbits were divided into three groups: control, SAH, and PDTC groups (n=14 for each group). The caliber of the basilar artery was evaluated. Nuclear factor-kappaB DNA-binding activity and the gene expression levels of cytokines and adhesion molecules in the basilar artery were measured. Immunohistochemical study was performed to assess the expression and localization of tumor necrosis factor (TNF)-alpha, intercellular adhesion molecule (ICAM)-1, and myeloperoxidase (MPO). It was observed that NF-kappaB DNA-binding activity was significantly increased by treatment with hemolysate in cultured VSCMs, but this increase was suppressed by pretreatment with PDTC. Severe vasospasm was observed in the SAH group, which was attenuated in the PDTC group. Subarachnoid hemorrhage could induce increases of NF-kappaB DNA-binding activity and the gene expression levels of TNF-alpha, interleukin (IL)-1 beta, ICAM-1, and vascular cell adhesion molecule (VCAM)-1, which were reduced in the PDTC group. Immunohistochemical study demonstrated that the expression levels of TNF-alpha, ICAM-1, and MPO were all increased in the SAH group, but these increases were attenuated in the PDTC group. Our results suggest that NF-kappaB is activated in the arterial wall after SAH, which potentially leads to vasospasm development through induction of inflammatory response.  相似文献   
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