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1.
Selecting a population of spermatozoa by the swim-up technique yields, after freezing and thawing, a population of cells that contains proportionally more spermatozoa which are morphologically normal, fewer spermatozoa with damaged tail membranes, and a greater percentage of progressively motile spermatozoa with greater velocities and amplitudes of head displacement than those obtained after freezing and thawing the same semen samples in the normal way. This pattern was found for the semen from 10 patients and five volunteers. However, the cells selected by swim-up were as susceptible to the stresses caused by freezing and thawing as unselected spermatozoa in the original semen sample, and the improvement came from the better quality of the initial sample.  相似文献   
2.
Multiple tests were done on the ejaculates of 10 asthenozoospermic patients and nine healthy normozoospermic volunteers in an attempt to identify individually the cause of low sperm motility in these patients. Possible defects in the sperm plasma membrane and the motility apparatus of sperm, and in epididymal function affecting the development of motility, were investigated. The presence of seminal sperm antibodies or any motility-inhibiting factors in the seminal plasma that could be removed by washing were also tested. Each test was positive in only one or two patients but axonemal dysfunction was identified in nine patients. Removal of seminal plasma from asthenozoospermic samples did not improve sperm motility to any greater extent than with donor ejaculates, and the motile sperm of these patients exhibited characteristics mostly similar to those of donors under various incubation conditions. Selection procedures are, therefore, required to obtain samples of good quality sperm from such asthenozoospermic ejaculates.  相似文献   
3.
目的探讨褪黑素受体1B基因(MTNR1B)多态性与骨密度之间的相关性。方法选取140名16~20岁之间的正常女性,采用双能X线骨密度吸收仪测量双侧近端股骨的骨密度。同时,采取外周静脉血,采用试剂盒提取DNA。根据人类单倍体图计划(HapMap)提供的汉族人数据,我们在MTNR1B基因上选取了6个标签SNP(tagSNPs)。通过PCR-RFLP的方法检测褪黑素受体1B基因上6个标签SNP的基因型。采用ANOVA的统计学方法比较不同基因型对应骨密度大小。结果MTNR1B基因6个多态性位点各基因型所对应的骨密度,没有明显差异(P>0.05)。结论褪黑素受体1B基因多态性与骨密度之间没有相关性。  相似文献   
4.
目的 通过磁共振成像(MRI)观察青少年特发性脊柱侧凸(AIS)和正常同年龄组青少年胸椎的形态学差异,探讨其临床意义.方法 胸椎轻度侧凸(MS)组患者10例(Cobb角15°~39°),胸椎中度侧凸(SS)组患者10例(Cobb角40°~75°).另选健康青少年10名作为对照(非侧凸组).所有研究对象均为女性,年龄13~14岁.用1.5 T磁共振扫描仪(Sonata,Siemens,Erlanger,德国)对所有研究对象进行全脊柱矢状面扫描,在图像工作站(Easy Vision,Philips Medical Systems,Best,荷兰)上重建脊柱矢状面图像,测量每个胸椎椎体前壁高度,后壁高度,棘突间高度,在横截面测量椎体横径长度,并进行对比分析.结果 椎体前后高度、宽度从T1到T12逐渐增加,并呈线性分布,脊柱侧凸组椎体高度普遍>正常同年龄非侧凸组患者.脊柱侧凸组患者椎体高度横径比值以及脊椎前后高度比值均>无侧凸组.胸椎侧凸顶椎区T6~T9椎体前方高度、椎体高度横径比值以及脊椎前后高度比值,脊柱侧凸组明显>非侧凸组,差异均有统计学意义(P<0.05).结论 AIS胸椎侧凸女性患者胸椎顶椎区存在显著的脊柱生长模式异常,与正常胸椎相比AIS的胸椎更高、并显得更为瘦长.  相似文献   
5.
See also Chandler WL, Yeung W, Tait JF. A new microparticle size calibration standard for use in measuring smaller microparticles using a new flow cytometer. J Thromb Haemost 2011; 9: 1216–24; Robert S, Poncelet P, Lacroix R, Raoult D, Dignat‐George F. More on: calibration for the measurement of microparticles: value of calibrated polystyrene beads for flow cytometry‐based sizing of biological microparticles. This issue, pp 1676–8; Mullier F, Bailly N, Chatelain C, Dogné JM, Chatelain B. More on: calibration for the measurement of microparticles: needs, interests, and limitations of calibrated polystyrene beads for flow cytometry‐based quantification of biological microparticles. This issue, pp 1679–81.DOI: 10.1111/j.1538‐7836.2011.04384.x .  相似文献   
6.
Kernicterus is a frequent occurrence in Chinese term infants. In a previous study, the mean level of serum bilirubin of 152 kernicteric infants was 35.4 mg/dl (605.3 μmol/l) and the range was 22.3-50 mg/dl. More recently, three further term infants developed kernicterus and one exhibited bilirubin level of only 23.3 mg/dl. Features of haemolysis were lacking in 56.8% of these infants. Evidence of brain damage occurred in 26.5% in a former series and in 5.5% of the more recent study of those infants who developed bilirubinaemia exceeding 20 mg/dl. Such a high risk favours the present practice of exchange transfusion for rising bilirubin beyond 20 mg/dl (342 μmol/l) in Chinese term infants.  相似文献   
7.
A pilot cord blood TSH screening program for congenital hypothyroidism was commenced in Hong Kong in April 1982. By April 1984, 14 411 neonates born in two hospitals were screened for this disorder. Five cases of primary hypothyroidism and two cases of transient hypothyroidism were detected. The detection of cases of congenital hypothyroidism with only moderately elevated cord blood TSH values means that the recall rate will remain high.  相似文献   
8.
Abstract Forty-two cases of severe staphylococcal infection occurring over a 10-year period in the neonatal unit at Queen Mary Hospital are described. There was a 4.5-fold increase in incidence in the latter half of the study period, when methicillin-resistant Staphylococcus aureus (MRSA) emerged. The isolated MRSA were also resistant to gentamicin, but sensitive to vancomycin, fusidic acid, co-trimoxazole and amikacin. Comparison between MRSA and methicillin-sensitive cases showed that the former was associated with a longer hospital stay after diagnosis. Overall mortality was 9.5%. Two cases with meningitis died. MRSA is at least as virulent as its methicillin-sensitive counterparts. The treatment implications of severe neonatal staphylococcal infection are discussed.  相似文献   
9.
Multiplane transthoracic echocardiography provides numerous sequential images by rotation of the transducer imaging array through 180° with the surface probe at a fixed site. We explored the potential of this new technique with a 3.7/5-MHz prototype multiplane transthoracic probe. Echoanatomic correlations were first examined in ten explanted hearts. The transducer was then applied in 30 normal humans at transthoracic acoustic windows to determine the imaging planes available. Use of this probe in 76 patients with various cardiac disorders indicated that this probe eases the procedure of transthoracic echocardiographic examination, provides incremental information for improved delineation and understanding of cardiac pathology, and yields many novel insights to echocardiographic interpretation. Multiplane transthoracic echocardiography appears to expand the versatility of transthoracic two-dimensional echocardiography.  相似文献   
10.
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