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51.
Chretien Marie Francoise; Lebouvier Brigitte; Denis Alain; Chappard Daniel 《Human reproduction (Oxford, England)》1998,13(10):2767-2771
A cytomorphometric analysis of superficial vaginal cells inwomen in three groups of different types of hormonal concentrationwas made. There were 15 women in each group. Group I was studiedduring a natural cycle, group II under oral contraceptive therapyand group III during an in-vitro fertilization (IVF) stimulationprotocol. Morphometric parameters were measured on an imageanalyser. The area, perimeter and several form factors weremeasured separately for nuclei and cytoplasm. The nucleus:cytoplasmicratio was also determined. The cytoplasmic area was significantlyreduced in group II and was associated with a statisticallysignificant reduction of the nuclear area. The nucleus:cytoplasmicratio appeared significantly increased in group II and reducedin group III. Low oestradiol impregnation obtained with an oralminidosed contraceptive interfered with vaginal cell maturation.High oestradiol concentrations obtained during IVF protocolsinduced marked nuclear pycnosis but did not induce supra-physiologicalcell enlargement. Maximal cell size is genetically regulatedaccording to Driesch's law of volume invariance and hormonalover-stimulation has no effect on cell size. The nucleus:cytoplasmicratio appears to be a powerful parameter reflecting the oppositeeffects of hormones on cell compartments. 相似文献
52.
The present study was designed to examine the effects of a >30kDa fraction of medium conditioned for 2 days by adult rat seminiferoustubules on inhibin secretion by cultured tubules, and on spermatogenesisand fertility of male rats. Inhibin secretion was assayed byadding the >30 kDa fraction to 5 cm segments of adult ratseminiferous tubules and measuring inhibin by radioimmunoassayat 2 day intervals. Fertility was assayed by injecting malerats daily for up to 45 days with the >30 kDa fraction andthen mating them with a proestrus female, or by injecting for15 days and mating them with two female rats. The assay usedto evaluate the in-vivo effect of the >30 kDa fraction onthe testis involved an assessment of frequencies of seminiferoustubule stages scored by transillumination on intact tubules.The addition of the >30 kDa fraction to the adult rat seminiferoustubules cultured for 2 days resulted in an inhibition of inhibinsecretion into the medium. This effect was reversed when thefraction was removed and changed with fresh medium and culturedfor a further 4 days. The >30 kDa fraction administered i.p.to adult male rats resulted in a low fertilization rate comparedto control rats (67%) (P < 0.05). The assessment of frequenciesof seminiferous tubule stages scored by transillumination showedan increased frequency of stage VI and decreased frequency ofstages VII and VIII after treatment. The results of the presentstudy provide additional evidence that local regulation of Sertolicell function is mediated by a >30 kDa component or componentssecreted by adult seminiferous tubules which could arrest spermatogenesis. 相似文献
53.
泵式自体输血过滤引流系统在急症救护中的应用 总被引:5,自引:1,他引:4
自体输血、胸腔闭式引流,是缓解血源矛盾、赢得抢救时机、防治心肺衰竭及ARDS/MOF的重要措施。笔者研制成功的手控泵式储血过滤引流系列在战地、灾害现场,以及平时的心肺手术中,共应用3000余例,现重点对其功能设计和用于自体输血、紧急救护做讨论和评估。 相似文献
54.
C. Caramella F. Ferrari M. C. Bonferoni M. E. Sangalli M. De Bernardi Di Valserra F. Feletti M. R. Galmozzi 《Biopharmaceutics & drug disposition》1993,14(2):143-160
Six preparations were considered: three multiple unit dosage forms (micropellets in capsules) (D, E and G) and one matrix tablet (B) were experimental prolonged release formulations, two non-disintegrating tablets (A and C) were commercial products. The in vitro dissolution behaviour of the differing formulations was investigated using the USP XXII paddle apparatus. The in vivo study was effected on a panel of 12 healthy volunteers. The two commercial tablets (A and C) showed mean dissolution time (MDT) of 1.34 and 1.44 h and td of 91 and 92 min, respectively; for prolonged release formulations (B, E, D, and G) MDT ranged between 2.28 and 4.23 h and td between 149 and 291 min. The mean residence time (MRT) was 8.68 and 6.47 h for tablets A and C, respectively; it ranged between 9.62 and 10.24 h for the multiple unit formulations E, D, and G and was 11.27 h for matrix B. Formulation B also showed the higher apparent elimination half-life t1/2 (7.12 h), while apparent t1/2 for all the other formulations were very similar, ranging between 5.04 and 5.28 h. High variability between the various formulations was found for Cmax and AUC values, and no relationships could be established with the type of formulation. An in vitro/in vivo correlation was found for all the formulations examined on the basis of analogous parameters (MDT and MRT); (r = 0.83, p <0.05). In a few cases the Wagner-Nelson deconvolution method was applied to individual plasma level versus time curves and the corresponding absorption curves were obtained. In these cases the in vitro/in vivo correlation was tested on the basis of the comparison of the in vivo absorption curves with the in vitro dissolution profiles. This was accomplished using the ‘Levy's plot’ (per cent released versus per cent absorbed) approach and provided further support for the correlation found. 相似文献
55.
Richard A. Hill Terri Esterowitz Julie Ryan Lih-Huei L. Liaw J. Stuart Nelson Hideko Yashiro Tatiana Krasieva Michael W. Berns 《Lasers in surgery and medicine》1995,17(2):166-171
Background and Objective: To investigate Photofrin® (PII) and CASPc for photodynamic therapy (PDT) of the ciliary body in rabbits. Study Design/Materials and Methods: PII (10 mg/kg) or CASPc (1 mg/kg) was given by ear vein. Pharmacokinetics were studied in frozen sections by fluorescence microscopy (CCD camera based low light detection system with digital image processing) at 1 and 24 h (8 rabbits;16 eyes). Laser light was delivered (argon pumped dye laser;630 and 675 nm;8 rabbits;16 eyes) by contact fiberoptic. To compensate for iris attenuation, irradiance was 125 mW/cm2 (20, 40, 80, or 160 J/cm2). Controls (4 rabbits;8 eyes) received laser light without photochemicals (OD) and for comparison, continuous wave Nd:YAG laser by fiberoptic (0.8–1.2J;OS). Results: Localization studies showed intravascular distribution with some selective ciliary body distribution at 24 h (PII > CASPc). Rabbits treated with PII or CASPc exhibited variable amounts of gross ciliary body edema, infarction, and necrosis by 24–48 h. This response was not seen in PDT control tissues;damage was seen in the iris and ciliary body, with partial vacuolization of the pigment epithelium. Conclusion: PDT may offer a more selective approach to ciliary body destruction. A small but significant thermal effect was seen during PDT from melanin photon uptake with damage to iris and ciliary body. Thermal damage and potential interaction with ocular visual pigments may limit use of these photochemicals and wavelengths for PDT of the ciliary body © 1995 Wiley-Liss, Inc. 相似文献
56.
57.
安吉复口服液的耐缺氧,耐低温和抗疲劳作用 总被引:2,自引:0,他引:2
采用缺氧、寒冷和负重游泳等方法,观察了安吉复口服液(0.025、0.1和0.4mg·kg~(-1),ig,qd×14d)对小鼠的耐缺氧、耐低温及抗疲劳作用.结果表明,安吉复口服液0.1、0.4mg·kg~(-1)可延长KCN中毒小鼠的存活时间及延长小鼠在寒冷环境中存活时间,而0.4mg·kg~(-1)可延长常压缺氧条件下小鼠存活时间及延长小鼠负重游泳时间. 相似文献
58.
H. Fuder S. Stiegler N. Wetzelsberger G. Wieckhorst R. Lange & P. W. Lücker 《British journal of clinical pharmacology》1997,44(6):527-530
Aims Concomitant administration of magnesium hydroxide may affect the rate or extent of absorption of non-steroidal anti-inflammatory drugs. In order to find out whether or not buffering modifies the pharmacokinetics of ketoprofen, plasma concentration-time courses resulting from oral administration of unbuffered formulations were compared with those of buffered formulations.
Methods Two groups of 12 healthy and young male subjects were included in two randomized cross-over studies and received single oral doses of ketoprofen 12.5 or 25 mg, respectively, given as tablets which were either unbuffered or buffered with magnesium hydroxide/citrate. Ketoprofen enantiomers in plasma were determined by h.p.l.c. up to 24 h post-dose.
Results Maximum plasma concentrations ( Cmax ) of both the (R)- and (S)-enantiomer, observed after administration of the buffered formulations (12.5 and 25 mg), were higher compared with the unbuffered tablets by about 50–80%. The area under concentration-time data (AUC) was unaffected, and, hence, C max /AUC was increased by buffering. Time to C max ( t max ) and mean residence time (MRT) tended to be or was shortened by buffering.
Conclusions It is concluded that buffering of two ketoprofen formulations with magnesium hydroxide/citrate enhanced the concentration maximum by increasing the rate of absorption and leaving AUC unaffected. 相似文献
Methods Two groups of 12 healthy and young male subjects were included in two randomized cross-over studies and received single oral doses of ketoprofen 12.5 or 25 mg, respectively, given as tablets which were either unbuffered or buffered with magnesium hydroxide/citrate. Ketoprofen enantiomers in plasma were determined by h.p.l.c. up to 24 h post-dose.
Results Maximum plasma concentrations ( C
Conclusions It is concluded that buffering of two ketoprofen formulations with magnesium hydroxide/citrate enhanced the concentration maximum by increasing the rate of absorption and leaving AUC unaffected. 相似文献
59.
对50只正常眼和47只青光眼进行阈值改良Amsler表与Humphrey静态分析仪视野检查比较,两种方法存在着相关关系,阳性检出率无区别,提示阈值改良Amsler表对青光眼早期视野损害有较高的检出率。 相似文献
60.
Purpose : To compare the clinical application value of Ultrasound biomicrsocpic dark room provocative test with the traditional dark room test in screening primary angle closure glaucoma (PACG).Methods: 22 eyes with PACG in prodromal stage and 30 eyes with deep anterior chamber and wide angle of 15 normal persons were observed in this trail. All 52 eyes were performed traditional dark room provocative test and ultrasound biomicorosopic darkroom test respectively. With different positive diagnostic criteria, the sensitivity of the two methods were compared using chi-squared analysis.Results : After staying in the dark room for 2 hours, In case group, IOP in 10 of 22 eyes rose more than 1. 07kPa(1kPa = 7.5mmHg), in 12 eyes less than 1.07kPa or had no changes; appositional angle closure were found by Goldmann gonioscopy in 8 eyes : 3 eyes in two quadrants, 5 eyes in more than two quadrants; the appositional angle closure was found by UBM in 15 eyes; 3 eyes in one quadrants, 5 eyes in two quadrants, 7 eyes 相似文献