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1.
SUSAN AVERY VIRGINIA N. BOLTON BRIDGETT A. MASON 《International journal of andrology》1990,13(2):93-99
The ability of sperm to swell in hypo-osmotic conditions was examined in 211 semen samples from the partners of patients about to undergo oocyte retrieval for in-vitro fertilization (IVF). The test was performed using aliquots of semen, the remainder of which was then prepared for IVF. No significant difference was found, in either the percentage of swollen sperm or the type of swelling response, between samples that achieved fertilization in vitro and those that did not, or between any of the diagnostic categories of infertility (tubal damage, unexplained infertility, oligospermia). In samples which achieved fertilization in vitro there were correlations between sperm swelling and sperm motility (r = -0.51) and abnormal morphology (r = 0.33), but no such correlations were demonstrated in samples that failed to achieve fertilization. Moreover, there was no significant difference between the percentage of swollen sperm in semen (mean motility 64%), in samples immediately after preparation for IVF (mean motility 96%) or in capacitated sperm 24 h after preparation (mean motility 91%). These results demonstrate that the hypo-osmotic sperm swelling test does not assist in the prediction of the fertilizing capacity of human sperm in vitro. 相似文献
2.
CLOSED CHAMBER SYSTEM FOR DELIVERY OF ETHANOL TO CELL CULTURES 总被引:3,自引:0,他引:3
ADICKES EDWARD D.; MOLLNER TERESA J.; LOCKWOOD SUSAN K. 《Alcohol and alcoholism (Oxford, Oxfordshire)》1988,23(5):377-381
The accuracy and consistency of the delivery of ethanol to culturedcells is important to determine effects on morphologic, biochemicaland physiologic alterations. Open and closed chamber systemswere evaluated to determine cytotoxic vs sublethal, potentiallyteratogenic effects on neonatal rat cardiac myocytes. The open system employed a variety of cell culture vessels.Cardiac cells were exposed directly to ethanol in the growthmedia at concentrations of 550 mM in Petri dishes, multiwellslides and multiwell chambers. Ethanol concentrations in themedia in these open vessels decreased over 60% in a 24 hr incubationperiod. A closed system consisted of tightly sealed plastic containersin which the same vessels were used. The vessels were placedon a platform over a bath of ethanol-water. Cells were acclimatedfor 24 hr with ethanol in the bath at 200% of the final desiredmedia concentration. Ethanol gradually diffused into the mediato reach peak levels of 5, 10,25 or 50 mM at 24 hr. After the24 hr period, ethanol was added to both the media and bath atthe desired concentration. Cells exposed gradually to ethanol in the closed chambers remainedviable, but showed slower division and growth. A period of gradualacclimation is required to induce sublethal cellular effectsrather than lethal effects. The diversity of cell systems andmanipulations of cultures to study the potential teratogeniceffects of ethanol are improved using such a closed chambersystem. 相似文献
3.
4.
P. KORKOLOPOULOU J. CORDELL M. JONES L. KAKLAMANIS A. TSENGA K.C. GATTER D.Y. MASON 《Histopathology》1994,24(6):511-515
Recent evidence indicates that membrane-bound immunoglobulin on B lymphocytes is associated with a molecule which comprises the products of the mb-1 and B29 genes. This molecule is a highly specific marker for B-cells, presumably because of its central functional role in antigen triggering, and has recently been clustered as CD79a at the 5th Leucocyte Workshop. Recently there has been controversy surrounding reports of B-cell antigen expression by Reed–Sternberg and related cells, and we have therefore studied 108 cases of Hodgkin's disease immunohistochemically using a novel antibody which detects mb-1 protein in paraffin sections. The results were compared with those achieved using antibody L26 to detect CD20. The mb-1 protein was present in the neoplastic cells in all 14 cases of lymphocyte predominance Hodgkin's disease studied, and CD20 immunoreactivity was also found in seven of the eight cases of this subtype studied. Of the non-lymphocyte predominance cases, 20% (19/94) expressed mb-1 and 30% (20/67) CD20 in the Reed–Sternberg cells, but the cells positive for either of these two markers usually constituted only a very small proportion of the neoplastic population. However, in occasional cases (one of 94 for mb-1 and five of 67 for CD20), more than 50% of the neoplastic cells expressed one or both B-cell antigens. These results confirm the B-cell origin of the neoplastic cells in lymphocyte predominance Hodgkin's disease, but they also indicate that, contrary to our previous study, mb-1 expression may occasionally be found in what appears, on histological grounds, to be other types of Hodgkin's disease. 相似文献
5.
6.
In an immunocytochemical study of 41 human lung tumours we have shown that Langerhans cells can be reliably identified using the anti-CD1 monoclonal antibody NA1/34. Langerhans cells are present in all the main varieties of human lung tumour although they are infrequent in both small cell carcinoma and carcinoid tumour. There is considerable variation in numbers of Langerhans cells in both adenocarcinomas and squamous cell carcinomas. In this study tumours were divided into those with high numbers of Langerhans cells (greater than 2 per high power field) and those with low numbers (less than 2 per high power field). Analysing these results against patient survival showed a markedly worse survival in those tumours with a high number of Langerhans cells for all the tumours as a single group and for squamous cell carcinoma as a single entity. 相似文献
7.
Heterogeneity of CD3 antigen expression in T-cell lymphoma 总被引:2,自引:0,他引:2
K. M. WOOD G. PALLESEN E. RALFKIAER R. WARNKE K. C. GATTER D. Y. MASON 《Histopathology》1993,22(4):311-317
CD 3 antigen expression was studied in a series of 98 T-cell lymphomas, using polyclonal antibodies which recognize this molecule in routinely processed, paraffin-embedded, tissue. We identified 40 cases in which CD3 was present on only a proportion of the neoplastic cells. This phenomenon of heterogeneous CD3 expression was commonest in pleomorphic T-cell lymphomas (22/42 cases) and in CD30 (Ki-1)-positive lymphomas (5/11 cases), and was less frequently observed in mycosis fungoides (4/18 cases) and not seen in T-cell lymphoblastic lymphoma (0/9 cases). CD3 expression was often related to cell morphology, with CD3 antigen being present on the smaller neoplastic cells but absent from the larger ones. The diagnostic significance of these observations is that, on occasion, it may be possible to diagnose a lymphoma as being of T-cell origin in paraffin sections by demonstrating a minor subpopulation of CD3-positive neoplastic cells. 相似文献
8.
TOM MASON 《Journal of clinical nursing》1993,2(2):95-102
Summary
- ? The terminology used in the published literature to indicate that a patient is being denied, or is denying themself, the company of other people is wide and varied.
- ? With ever growing concerns of the rights, both civil and legal, of patients receiving treatment, either solicited or unsolicited, there is a need to identify the patterns of practice in any given organization and to establish their relationship to the terminological semantic.
- ? The Special Hospitals, who cater for those patients requiring a high degree of security, have been assumed to use seclusion to a greater degree than any other form of personal-space facility, either forced by the staff or elected by the patient. However, this has largely been based on hearsay and speculation.
- ? Seclusion may be perceived as a clinical psychiatric intervention to prevent the serious deterioration of a person's mental state or as a method of containment of a dangerous situation when all else fails.
- ? This study was based on a survey of all seclusion facilities within the Special Hospital system and discussions with over 100 nursing staff about the differing types and methods of providing patient withdrawal from the ward community for whatever reason.
- ? The results highlighted a clear uniformity of practice throughout the system despite the differing terminologies used.
9.
REDUCED FREQUENCY OF LUTEINIZING HORMONE PULSES IN WOMEN WITH WEIGHT LOSS-RELATED AMENORRHOEA AND MULTIFOLLICULAR OVARIES 总被引:3,自引:0,他引:3
H. D. MASON M. SAGLE D. W. POLSON D. KIDDY D. DOBRIANSKY J. ADAMS S. FRANKS 《Clinical endocrinology》1988,28(6):611-618
We have studied pulsatile secretion of LH in 10 women with secondary amenorrhoea and multifollicular ovaries (MFO). This group of patients have a history of mild to moderate, or partially recovered weight loss. They have normal basal LH concentrations but evidence of oestrogen deficiency suggesting a hypothalamic abnormality of gonadotrophin regulation. The results of gonadotrophin pulse analysis were compared with those in normal women during the early follicular phase of the cycle. The mean LH concentration during the 8 h study (5.0 +/- 0.9 [SD] U/l) was not significantly different from that in normal women (5.7 +/- 2.5). There was no difference between the groups in mean LH pulse amplitude (2.1 +/- 0.5 in MFO; 2.2 +/- 1.3 in normal women). The frequency of LH pulses was, however, significantly lower in women with MFO (2.8 +/- 1.6 vs 4.8 +/- 1.5, P less than 0.05). Two women with MFO had LH pulses of normal frequency. One subsequently developed a normal pattern of ovarian follicles. The other showed a sleep-related rise in LH concentrations during a 24 h profile which was similar to the pattern of gonadotrophin secretion normally observed during late puberty. These results show that women with MFO have a hypothalamic disturbance of gonadotrophin regulation with slowing of LH pulses without a diminution of pulse amplitude. 相似文献
10.
Wireless Ultrasound Guidance for Femoral Venous Cannulation in Electrophysiology: Impact on Safety,Efficacy, and Procedural Delay 下载免费PDF全文
DANIEL RODRÍGUEZ MUÑOZ M.D. EDUARDO FRANCO DÍEZ M.D. JAVIER MORENO M.D. Ph.D. GIUSEPPE LUMIA M.D. ALEJANDRA CARBONELL SAN ROMÁN M.D. TERESA SEGURA DE LA CAL M.D. ROBERTO MATÍA FRANCÉS M.D. Ph.D. ANTONIO HERNÁNDEZ MADRID M.D. Ph.D. JOSÉ LUIS ZAMORANO GÓMEZ M.D. Ph.D. 《Pacing and clinical electrophysiology : PACE》2015,38(9):1058-1065