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A Mannini-Palenzona A M Bartoletti L Foa-Tomasi F Costanzo M Borgatti M Tognon E Cassai 《Journal of medical virology》1985,15(1):17-28
The analysis of 23 clinical isolates of herpes simplex virus type 1 (HSV-1) showed that 15 of 15 isolates that had undergone a few passages in tissue culture (fresh isolates) and two of eight isolates that had never been passaged (new isolates) were composed of a mixed population with respect to plaque morphology in Vero cells. Cloning and characterization of 10 large plaque viruses (L variants) and nine small plaque viruses (S variants), obtained from seven different isolates, showed the following. BamHI DNA restriction patterns of the L and the S variants from a single isolate differed only with respect to the electrophoretic mobility of the fragments that contain reiteration of specific sequences; they did not differ regarding the presence or the absence of restriction endonuclease cleavage sites. The L and S variants differed with respect to the electrophoretic profiles of infected cell glycoproteins, thermosensitivity of growth and plaquing efficiency at 39 degrees C, and, at least in the case of the two couples of variants that we tested, pathogenicity for the mouse. The hypothesis that the L variants might arise from the S variant during in vivo replication is discussed. 相似文献
3.
皮肤穿支血管的解剖学研究 总被引:18,自引:6,他引:18
目的:对全身皮肤血管区域进行定性和定量分析,确定全身皮肤穿支血管的位置、数量、口径、穿支蒂的长度、类型、来源血管以及穿支所供应皮肤的面积,为穿支皮瓣提供血管解剖基础。方法:选用10具新鲜尸体,采用改良氧化铅一明胶灌注技术进行动脉灌注。将每个口径大于0.5mm的穿支血管进行解剖并记录。拍摄X线片以显示皮肤内血管的形态和分布。定量数据分析包括全身各部位的穿支血管的数量、口径、类型及其供应区域的面积。结果:发现全身128支起源血管发出440支穿支供应皮肤。其中肌皮穿支与肌间隔穿支之比为3:2。穿支平均直径为0.7mm。穿支血管的分布规律如下:①躯干皮肤的血供主要来自肌皮穿支,这些穿支在皮肤内的走行距离和分布范围大于肢体皮肤的穿支。②肢体皮肤的血供主要来自肌间隙穿支血管,主要分布在深筋膜表面,皮神经和浅静脉周围穿支之间形成链式血管吻合。③单位面积的穿支数量与皮肤的移动程度成反比,穿支的口径大小和穿支在皮肤内走行距离与皮肤移动度成正比,与穿支的供应面积成正比。结论:本研究提供详细的皮肤穿支血管解剖数据,为临床设计应用穿支皮瓣提供解剖学依据。 相似文献
4.
目的 了解湖南省浏阳市居民新鲜水果摄入频率情况,探讨新鲜水果摄入频率与脑卒中发病关联。 方法 利用中国慢性病前瞻性研究湖南省浏阳市项目点30~79岁常住居民基线调查数据和随访获得的脑卒中发病数据,利用Cox比例风险模型,在调整混杂因素后,评估新鲜水果摄入频率与脑卒中发病的关联。 结果 共57 288名研究对象纳入分析,浏阳市仅7.38%的研究对象每周有4 d及以上吃新鲜水果 。男性、家庭年收入水平低、文化程度低、吸烟、饮酒人群新鲜水果摄入频率较低(P<0.001)。2015—2019年共随访观察到2 720例脑卒中发病。增加新鲜水果摄入频率对脑卒中的发病有保护作用,与不吃或极少吃新鲜水果相比,每周有4 d及以上吃新鲜水果脑卒中的发病风险降低了28%(HR=0.72,95%CI:0.61~0.85),缺血性脑卒中的发病风险降低了25%(HR=0.75,95%CI:0.60~0.94),出血性脑卒中的发病风险降低了51%(HR=0.49,95%CI:0.35~0.76)。 结论 新鲜水果摄入频率增加能降低脑卒中发病风险。浏阳市居民新鲜水果摄入频率情况不容乐观,针对这一问题,需要采取适当措施以增加居民新鲜水果摄入频率。 相似文献
5.
目的:为恢复失去卵巢功能妇女体内性激素的作用,本实验将大鼠卵巢异体皮下移植,观察移植效果。方法:分别将SD大鼠新鲜卵巢及培养后卵巢异体皮下移植。通过观察阴道脱落细胞、子宫重量的变化,移植物的组织形态学及测定血清雌二醇(E2)水平了解卵巢移植鼠体内激素分泌状况。结果:新鲜移植组,3/10只受体鼠阴道脱落细胞显示有雌激素作用,子宫重量及血清E2显著高于去势组,移植物表面无明显血管网形成,组织切片可见大量原始卵泡和及少量发育卵泡。培养后移植组,6/10只受体鼠阴道脱落细胞显示有雌激素作用,子宫重量及血清B水平显著高于去势组,与新鲜移植组无显著差别。移植物表面可见少量微血管分布,组织切片可见较多的发育卵泡。结论:异体皮下移植可降低组织的免疫源性,而经体外培养后可进一步降低免疫源性,利于移植物存活,为临床组织器官同种异体移植提供实验依据。 相似文献
6.
Adva Aizer Olga Dratviman-Storobinsky Meirav Noach-Hirsh Sarah Konopnicki Alon Lazarovich Gil Raviv Raoul Orvieto 《Andrologia》2021,53(1):e13849
We sought to compare ICSI outcomes of cycle using fresh versus thawed TESE spermatozoa obtained during the previous fresh TESE. All consecutive couples undergoing ICSI cycles using fresh TESE spermatozoa, followed by ICSI cycle using cryopreserved sperm remaining from the previous fresh TESE procedure were included. Ovarian stimulation (OS)/laboratory variables and cycle outcome were assessed and compared between those utilising fresh versus thawed TESE spermatozoa. Seventy-five couples were evaluated, with no in-between groups differences in OS nor embryological variables. While implantation and LBR per embryo transfer were nonsignificantly higher in the frozen as compared to the fresh TESE, there was a trend towards higher LBRs per patient in the frozen TESE group. The cumulative miscarriage rate (4% versus 14.7%, p < .022 respectively) was significantly lower and the cumulative LBR (34.7% versus 16%, p < .007 respectively) was significantly higher using frozen TESE spermatozoa. Moreover, significantly higher proportion of frozen TESE sperm samples used pentoxifylline to enhance sperm motility. In conclusion, the results of ICSI cycles using frozen TESE spermatozoa are as good, or even better than using fresh TESE spermatozoa. Further studies are required to explore the factors responsible for the improved ICSI outcome, while using frozen versus fresh TESE sperm samples. 相似文献
7.
目的 优选人参Panax ginseng趁鲜切制饮片工艺,比较分析趁鲜切制与传统切制人参饮片的质量,为人参趁鲜切制的合理性提供数据支持。方法 考察切片厚度、烘干温度、烘干时间等因素优选人参趁鲜切制饮片最佳制备工艺;建立指纹图谱结合化学计量法评价2种炮制工艺人参饮片质量差异性;并定量分析2种人参饮片中指标性成分人参皂苷含量差异。结果 人参趁鲜切制饮片的最佳制备工艺为人参鲜药材含水量65%,烘干温度50℃、烘干时间8 h、切片厚度1.5 mm;指纹图谱分别确定了人参趁鲜切制饮片和传统切制工艺饮片22个共有峰,指认了其中7个共有峰,2种炮制工艺所得人参饮片指纹图谱相似度分别在0.983~0.992、0.948~0.996。趁鲜切制与传统切制工艺饮片之间的指纹图谱相似度为0.960~0.993,相似度良好;主成分分析(principal component analysis,PCA)将人参趁鲜切制饮片和传统切制饮片归为2类,正交偏最小二乘法-判别分析(orthogonal partial least squares-discriminant analysis,OPLS-DA)确定2种炮制工艺项... 相似文献
8.
Samples of human allograft skin prepared without freezing ("fresh skin) were found to have electrical and sodium ion transport properties which differed only slightly from those of skin which had been similarly treated but stored frozen (frozen skin). The fresh skin samples were less permeable to sodium ions during passive diffusion and less conductive than frozen skin at low current levels. They were more permselective for sodium versus chloride during constant-current iontophoresis and showed slightly more asymmetry in their current–voltage properties. Overall, the electrical behavior of the two tissues was similar enough to support the use of frozen tissue in iontophoresis studies. However, caution should be exercised when considering the use of frozen skin for applications, such as those based on electroosmosis, where the observed differences could have a major impact on the results. 相似文献
9.
新鲜羊膜移植治疗眼表疾病的临床评价 总被引:3,自引:0,他引:3
目的 评价新鲜人羊膜在眼表重建术手术中的临床价值。方法 用新鲜羊膜移植,治疗陈旧性睑球粘连、结膜囊缺失,复发性翼状胬肉、蚕蚀性角膜溃疡、热烧伤后角膜和结膜溶解等眼表疾病的连续病例19例(21只眼)。结果 19例患者的羊膜移植手术均为一次成功。平均随访12.5个月,羊膜移植片未见免疫排斥反应或溶解吸收。手术后,患者的睑球粘连松解,结膜囊形成,蚕蚀性角膜溃疡和复发性翼状胬肉在随访期间未见复发,角膜和结 相似文献
10.
Summary 162 patients discharged from hospital after myocardial infarction were randomly allocated to two groups, one received alprenolol 400 mg daily and the other served as the control. The period of follow-up was two years and all other treatment given was standardized. The two groups did not differ with respect to risk factors for myocardial infarction, the course of the acute infarct or treatment during follow-up. After two years one patient in the group treated with alprenolol had died suddenly as compared to nine in the control group. During the same period four fresh infarcts had occurred in the alprenolol group compared to 15 in the control group. Both these differences were statistically significant. Only four patients were obliged to discontinue -blocker treatment because of suspected side-effects. Long-term post-infarction treatment with -blockers appears to be an effective form of secondary therapy without serious side-effects. 相似文献