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21.
Demetrius Ellis Ron Shapiro Mark L. Jordan Velma P. Scantlebury Nisan Gilboa Laszlo Hopp Nancy Weichler Andreas G. Tzakis Richard L. Simmons 《Pediatric nephrology (Berlin, Germany)》1994,8(2):193-200
Clinical aspects of FK-506 or cyclosporine immunosuppression regimens were evaluated in 48 consecutive pediatric renal transplant recipients. Tapering and discontinuation of prednisone was employed only in children receiving FK-506 who experienced minor or no rejection episodes during the 1st posttransplant month. At 1 year follow-up, 17 of 22 (77%) of all children with functioning allografts were receiving no prednisone (n=13) or a mean dosage of 0.07 mg/kg per day (n=4). During the 1st month, acute cellular rejection was more common in the FK-506 group (0.58 vs. 0.21 rejections per patient,P<0.05) but allograft survival (92%) and renal function at 1 year posttransplant were identical in both groups. Compared with the cyclosporine regimen, FK-506 immunosuppression may be associated with a higher incidence of cytomegalovirus or reversible Epstein-Barr virus-induced lymphoproliferative disease. However, the FK-506 group had less hirsutism and gingival hypertrophy and required fewer antihypertensive medications independent of steroid use. Height standard deviation scores and weight-for-height index improved only in preadolescents receiving FK-506 but no prednisone (P<0.02 andP<0.05, respectively), but did not differ between children on FK-506 plus prednisone and those in the cyclosporine group. We conclude that the major advantages of FK-506 over cyclosporine immunosuppression are a reduced severity of hypertension and an improved cosmetic appearance which may improve long-term medical compliance. When used as monotherapy, FK-506 also shows promise in relieving the growth retardation associated with cyclosporine regimens that include prednisone. 相似文献
22.
M. -H. Smet F. de Zegher M. Vanderschueren-Lodeweyckx G. Marchal 《European radiology》1992,2(1):57-61
In this study, magnetic resonance imaging (MRI) was performed to document potentially present morphostructural abnormalities of the hypothalamopituitary region in seven infants (age 0–21 months) who presented very early in life with clinical and biochemical evidence of hypopituitarism. Four infants had associated congenital cerebro-facial malformations.The following anatomical abnormalities were identified in variable combinations: ectopic neurohypophysis absence of the pituitary stalk, extreme elongation of the pituitary stalk, aplasia of the anterior pituitary lobe and no identification of the hypothalamopituitary complex.MRI proved to be very sensitive in the identification of structural malformations of the hypothalamopituitary region in infants with or without cerebro-facial malformations. AllhwuLll the magnetic resonance image does not appear to be a good predictor of endocrine dysfunction, it provides us more insight into the precise aetiology of this disorder and may be therefore of diagnostic, prognostic and therapeutic importance. 相似文献
23.
M. Kneissel P. Roschger W. Steiner D. Schamall G. Kalchhauser A. Boyde M. Teschler-Nicola 《Calcified tissue international》1997,61(2):95-100
There is abundant data on cancellous bone in the aging human spine, but little relating to the growing vertebral cancellous
bone in childhood and adolescence. The purpose of this study was to map vertebral cancellous bone in a growth and age series
of historic skeletal samples and to make comparisons with data published on recent material. Lumbar vertebral bodies were
collected from 65 skeletons (0–60 years) from a medieval Nubian population. Ethnohistoric information was collected to interpret
conditions that might have influenced bone structure and metabolism. The cancellous bone was studied three dimensionally,
using stereophotography and scanning electron microscopy and morphometrically by performing a semiautomatic structural analysis
on digitized backscattered electron images of polymethacrylate-embedded material. The cancellous bone structure in the children
consisted mainly of a densely packed, uniform network of small rodlike trabeculae. The greatest bone volume fraction with
small, more platelike trabeculae was observed during adolescence. In young adults, larger platelike trabeculae were present
in the central zone and smaller trabeculae in the superior and inferior zones, as described for modern skeletal material.
Structural changes associated with aging were observed much sooner than in modern man. By the estimated age of approximately
50–60 years, the predominant architectural elements were slender rarified rods in both sexes. The ethnohistorical data suggest
that this was essentially a black African population of physically active peasants, not likely to suffer Vitamin D insufficiency
or deficient calcium intake. Thus an earlier onset of the biological age changes in cancellous bone found in modern populations
was probably prevalent.
Received: 1 March 1996 / Accepted: 31 December 1996 相似文献
24.
G. J. Breur M. D. Lapierre K. Kazmierczak K. M. Stechuchak G. P. McCabe 《Calcified tissue international》1997,61(5):418-425
In this study, we tested the hypotheses that (a) both the domain volume (volume of the cell and the matrix it has formed)
and matrix volume of juxtametaphyseal hypertrophic chondrocytes in the growth plate is tightly controlled, and that (b) the
domain volume of juxtametaphyseal hypertrophic chondrocytes is a strong determinant of the rate of bone length growth. We
analyzed the rate of bone length growth (oxytetracycline labeling techniques) and nine stereologic and kinetic parameters
related to the juxtametaphyseal chondrocytic domain in the proximal and distal radial and tibial growth plates of 21- and
35-day-old rats. The domain volume increased with increasing growth rates, independent of the location of the growth plate
and the age of the animal. Within age groups, the matrix volume per cell increased with increasing growth rates, but an identical
growth plate had the same matrix volume per cell in 21- and 35-day-old rats. The most suitable regression model (R
2= 0.992) to describe the rate of bone length growth included the mean volume of juxtametaphyseal hypertrophic chondrocytes
and the mean rate of cell loss/cell proliferation. This relationship was independent of the location of the growth plate and
the age of the animal. The data suggest that the domain volume of juxtametaphyseal hypertrophic chondrocytes, as well as the
matrix volume produced per cell, may be tightly regulated. In addition, the volume of juxtametaphyseal hypertrophic chondrocytes
and the rate of cell loss/rate of cell proliferation may play the most important role in the determination of the rate of
bone length growth.
Received: 2 December 1996 / Accepted: 24 March 1997 相似文献
25.
G. Rosa G. Conti P. Orsi F. D'Alessandro I. La Rosa G. Di Giugno A. Gasparetto 《Acta anaesthesiologica Scandinavica》1992,36(2):128-131
The effects of sedative-hypnotic doses of propofol on respiratory drive and pattern have not yet been extensively described. Repeated small boluses of propofol (0.6-0.3 mg.kg-1) were administered to ten ASA I patients undergoing carpal tunnel release using regional anaesthesia. Airway pressure, capnography and pneumotachography were continuously recorded. With respect to basal values, no significant variations of respiratory rate, minute volume, tidal volume, inspiratory and expiratory time, total expiratory cycle, Ti/Ttot, TV/Ti, P0.1, EtCO2 and blood gas analysis were observed. Low doses of propofol, to maintain conscious sedation of light sleep, have not been shown to cause respiratory depression. 相似文献
26.
神经生长因子几丁质管修复兔面神经缺损 总被引:8,自引:0,他引:8
目的:评价神经生长因子(nerve growth factor,NGF)几丁质管在修复兔面神经缺损中的作用。方法:在16只新西兰兔的两侧面神经上颊支上分别造成8mm缺损,左侧用管腔内注入NGF的几丁质管修复,右侧用自体神经移植修复作对照。术后8周和16周分别取8只动物进行电生理和组织学检查及计算机图像分析。结果:术后8周,实验组的再生神经已通过近远中吻合口,神经纤维密集成束;术后16周,再生神经纤维的数量增加,神经纤维束增粗,形态接近于正常神经。电生理检测和图像分析显示实验组和对照组的神经传导速度和有髓神经轴突总截面积均无显著差异(P>0.05)。结论:NGF几丁质管可为免面神经缺损提供良好的修复环境。 相似文献
27.
A. E. P. Villa E. M. Rouiller G. M. Simm P. Zurita Y. de Ribaupierre F. de Ribaupierre 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》1991,86(3):506-517
Summary Single unit activity of 355 cells was recorded in the auditory thalamus of anesthetized cats before, during, and after the inactivation by cooling of the ipsilateral primary auditory cortex (AI). Most of the units (n = 288) showed similar functional characteristics of firing before and after the cryogenic blockade of AI. The spontaneous firing rate remained unchanged by cooling in 20% of the units and decreased in the majority of them (60%). In some regions, i.e. dorsal division of the medial geniculate body (MGB), lateral part of the posterior group of the thalamus, and auditory sector of the reticular nucleus of the thalamus, the maximum firing rate evoked by white noise bursts was generally affected by cooling in the same direction and to the same extent as the spontaneous activity. Units in the ventral division of MGB showed a characteristic increase of signal-to-noise ratio during cortical cooling. The corticofugal modulation led to the appearance or disappearance of the best frequency of tuning in 51 units and changed it by more than 0.5 octave in 34 units. The bandwidths of different response patterns to pure tones stimulation were used to define a set of functional properties. During cryogenic blockade of AI, two cortically modulated sub-populations of units were usually distinguished that exhibited changes for a given functional property. The complexity and diversity of the effects of cortical inactivation suggest that the corticothalamic projection may be the support for selective operations such as an adaptive filtering of the incoming acoustic signal at the thalamic level adjusted as a function of cortical activity. 相似文献
28.
Edward C. Kohaut John Whelchel F. Bryson Waldo Arnold G. Diethelm 《Pediatric nephrology (Berlin, Germany)》1987,1(2):150-153
Nine infants, who presented with renal failure within the first 3 months of life, were treated with continuous ambulatory peritoneal dialysis (CAPD). Seven infants survived to an age of 12–15 months, when they received transplants. Two patients died while on CAPD. Six infants are alive with a functioning renal allograft, at an average age of 35.5 months and an average of 22 months post-transplant. Neurological development is normal in four of the six infants tested. The mean current height of the six transplant recipients is just below 2 SD from the mean. 相似文献
29.
目的:探讨前列腺基质增生的发病机制与性激素以及相关生长因子的关系。方法:应用RT-PCR的方法研究了在人前列腺不同细胞类型中Smoothelin的表达,研究了雄、雌激素受体及相关生长因子在前列腺基质细胞中的表达,以及它们在前列腺基质细胞分化中表达的变化。结果:Smoothelin是前列腺平滑肌细胞特异性的标记蛋白;雄激素受体(AR)、碱性成纤维细胞生长因子(bFGF)、角化细胞生长因子(KGF)主要在前列腺成纤维细胞中表达,而雌激素受体(ER)、转移生长因子β1(TGFβ1)主要在平滑肌细胞中表达。结论:前列腺基质增生与雌激素受体和转移生长因子β1的过度表达密切相关。 相似文献
30.
Biochemical and ultrastructural alterations produced by miconazole and econazole in Trypanosoma cruzi 总被引:6,自引:0,他引:6
R Docampo S N Moreno J F Turrens A M Katzin S M Gonzalez-Cappa A O Stoppani 《Molecular and biochemical parasitology》1981,3(3):169-180
Miconazole and econazole, two fungicide imidazole derivatives, completely inhibited growth of Trypanosoma cruzi (Tulahuen strain) at concentrations of about 20 muM. Culturing of T. cruzi in the presence of lower doses of imidazole derivatives produced: decrease of 5,7-diene sterol content in epimastigotes (including ergosterol); disappearance of the nuclear chromatin, vacuolization and decrease in the electron density of the cytoplasm; selective surface alterations as revealed by an increased response to wheat-germ- and phytohemagglutinin. At variance with the effect of miconazole on Candida (De Nollin et al. (1977) Antimicrobial. Agents Chemother. 11, 500-513), miconazole and econazole, under the experimental conditions used, did not increase the rate of hydrogen peroxide generation by T. cruzi. 相似文献