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71.
Huang Tien L. Székács András Uematsu Tamon Kuwano Eiichi Parkinson Andrew Hammock Bruce D. 《Pharmaceutical research》1993,10(5):639-648
Thirty carbonates, thiocarbonates, carbamates, and carboxylic esters of -naphthol, -naphthol, and p-nitrophenol were synthesized and tested as substrates for liver carboxylesterases from the crude microsomal fractions of human and mouse, and purified isozymes, hydrolases A and B, from rat liver microsomes. The carbonates, thiocarbonates, and carboxylic esters of -naphthol were cleaved more rapidly than the corresponding -naphthol isomers by the mammalian liver esterases. -Naphthyl esters of acetic, propionic, and butyric acids were among the best substrates tested for these enzymes. The majority of the substrates was consistently hydrolyzed at higher rates by hydrolase B compared with hydrolase A, although the Michaelis–Menten constant (K
m) values of selected substrates differed widely with these two isozymes. Malathion was a 15-fold better substrate for hydrolase B than for hydrolase A. Compared with the corresponding carboxylates, the carbonate moiety of - and -naphthol and p-nitrophenol lowered the specific activities of the enzymes by about fivefold but improved stability under basic conditions. The optimum pH of mouse liver esterase with the acetate, methylcarbonate, and ethylthiocarbonate of -naphthol was between pH 7.0 and pH 7.6. Human and mouse liver microsomal esterase activities were about five orders of magnitude lower than the esterase activities of purified rat liver hydrolase B. A relationship between the catalytic activity of the enzymes and the lipophilicity of the naphthyl substrates indicated that (i) in the - and -naphthyl carbonate series, an inverse relationship between enzyme activity and lipophilicity of the substrates was observed, whereas (ii) in the -naphthyl carboxylate series, an increase in enzyme activity with increasing lipophilicity of the substrates up to a log P value of about 4.0 was observed, after which the enzyme activity decreased. 相似文献
72.
目的寻找控制分清五淋丸质量的方法。方法利用薄层色谱对其中大黄、黄柏、黄芩和栀子4种主药进行检出研究。结果样品不仅与黄连素、黄芩素和栀子甙对照品有一致的层析斑点,且与对照药材有一致或基本一致的层析斑点。结论薄层色谱方法是控制分清五淋丸质量的有效方法。 相似文献
73.
The objectives of this study were: i) to analyse the effects of morphine and naloxone on the rat's behaviour in the hot plate test using an ethological approach, and ii) to compare the effectiveness of repeated versus single test paradigms. Animals received either morphine (0, 3, 6 or 9 mg/kg SC) or naloxone (0, 0.01, 0.1 or 1 mg/kg SC). For repeated hot plate measures, rats were tested before and 60, 120, 180 and 240 min following morphine treatment, as well as 30, 60, 90 and 120 min after naloxone injection. For the single test schedule, rats were tested only once 60 min after morphine or 30 min after naloxone administration, or at 60, 120, 180, 240 and 300 min after 9 mg/kg morphine treatment. Behaviour was videotaped and analysed by an ethogram and ethological techniques. A cluster analysis revealed that the most frequently displayed patterns could be categorised into exploratory sniffing reactions (walk-sniff, immobile-sniff) and noxious-evoked elements, including primary (paw-licking, stamping), escape (jumping, leaning posture) and independent (hindleg-withdrawal) patterns. During repeated tests, morphine treatment induced: i) a maximum hypoalgesic effect 60 min post-injection (noxious-evoked patterns were significantly reduced), and ii) an unexpected thermal hyperreactivity rebound effect after 120 min (paw-licking and hindleg-withdrawal were enhanced), although changes in hindpaw-licking are more indicative of a hyperalgesic rebound effect. Most changes were quite similar during the single test schedule at 60 and 120 min after morphine injection. With regard to naloxone treatment, jumping latency was significantly decreased during the repeated test schedule, but not on single exposure to the plate. Other elements were facilitated, however, in the single test (stamping, leaning posture, hindleg-withdrawal). The results indicated that both repeated and single tests paradigms are of value for testing the effects of morphine and naloxone on rats. However, under our conditions the single test paradigm gave a better picture of the overall effects of the drug. Learning as well as habituation and sensitization may mask certain effects during repeated tests. In conclusion, an ethological analysis of the rat's behaviour in the hot plate test following administration of morphine and naloxone has been validated in this study. 相似文献
74.
目的:推荐使用胫骨外侧钢板。方法:将107例Ⅰ°、Ⅱ°开放性胫骨骨折随机分组,分别采用胫骨外侧钢板和普通加压钢板治疗,随诊1年~2.5年,比较两组术后功能和感染发生率。结果:发现两组功能评价无显著差异,但胫骨外侧钢板组感染发生率及骨髓炎发生率均明显低于普通加压钢板组(P<0.05)。结论:胫骨外侧钢板能明显降低开放性胫骨骨折的感染率和骨髓炎发生率,值得推荐。 相似文献
75.
The present study is divided into 2 parts: The first explains the concept of stimulating plate therapy at the Muenster Clinic and the second presents a longitudinal study of mouth and tongue posture in trisomy 21 children treated with this concept.47 children underwent a pre-treatment examination (Rec1), and 38 attended a first follow-up examination (Rec2) after an average of 4 months of stimulating plate treatment. The second follow-up examination (Rec3) was on average 53 months after the end of treatment and covered 18 patients. Data acquisition was based on standardized parent questionnaires and standardized clinical examination records. Rec2 showed in part a highly significant improvement in orofacial appearance. These results were confirmed by the parent interview, according to which the mouth and tongue posture improved in 76.3% of the children during the time they were wearing the plate. Even when the plate was not in place, the result remained stable in 65.8% of the patients. Up to Rec3, further improvement was recorded in some results. The symptoms: mouth mostly wide open and tongue mostly protruding way over lips were reduced. The number of children whose tongue was mostly in the oral cavity increased correspondingly.At Rec3, the parents also rated the mouth posture in 88.9% and the tongue posture in 77.7% of the children as stable or further improved.It can be concluded from the results of this study that stimulating plate treatment in combination with physiotherapy provides a long-term improvement in the mouth and tongue posture of children with Down's syndrome. 相似文献
76.
目的:探讨解剖Y型钢板的临床应用价值。方法:报告36例解剖Y型钢板内固定肱骨远端粉碎性骨折,进行临床分析讨论,其中列,女8例,平均年龄36.8岁。36例中均行肘后标准切口尽骨鹰嘴截骨暴整个肱骨远端,Y型钢板、螺钉内固定。结果:本组随访1~5年,其中优良率86.2%。结论:解剖Y型钢板治疗治疗肱骨远端粉碎骨折,效果确切,术后有利早期活动关节,减少并发症。 相似文献
77.
Moghal NE Milford DV White RH Raafat F Higgins R 《Pediatric nephrology (Berlin, Germany)》1999,13(9):778-781
The finding of familial haematuria without a history of deafness or renal impairment is often assumed to indicate a benign
prognosis. However, we describe three families in whom Alport and thin basement membrane nephropathy were separately identified
within the same pedigree. Our findings illustrate the importance of fully investigating families with haematuria, even if
thin basement nephropathy has been diagnosed in one member.
Received: 24 June 1998 / Revised: 2 June 1999 / Accepted: 3 June 1999 相似文献
78.
H. -G. Kempf U. Zimmermann H. P. Zenner 《European archives of oto-rhino-laryngology》1996,253(1-2):5-10
Motile properties of outer hair cells (OHCs) may contribute to sharp tuning and amplification in the mammalian cochlea. Shape changes of isolated OHCs in response to various physical and chemical influences have been investigated intensively. However, determinations of shape may have been influenced by unanticipated effects of preparation and preservation of the OHCs investigated. Thus, in a first step, lengths of freshly isolated OHCs from the guinea pig cochlea were determined using a video-enhancing magnification system. The cuticular plate/cell axis angle (CP/CA angle) was then measured in native cells and under the influence of potassium chloride and potassium gluconate incubation. To show the influence of glutaraldehyde (GA) fixation on the isolated OHCs, fixative dependent changes on cell length and CP/CA angle were recorded in native and preincubated OHCs. In these experiments, the cell length of vital isolated OHCs was between 41.5 m, in the basal turn, and 103.7 m, in the apical turn. The average CP/CA angle was 106° ± 4.2° (n = 324 cells, turns 1–4) with no statistically significant differences for the four turns. Under the influence of potassium chloride, cell length was reduced by 8.1%. Potassium gluconate incubation led to a shortening of cell length, followed by a 5.3% increase after 5 min. The CP/CA angle under potassium chloride was decreased (97.0°) and was then increased under the influence of potassium gluconate (110.7°) as a result of cuticular plate tilting. Cell shrinkage after fixation depended on the fixative's osmolarity and on the GA concentration. Increased GA levels amplified cell shrinkage from 34% for hypo-osmolar solutions to 15% in iso-osmolar and 29% in hyperosmolar solutions. The CP/CA angle of native and incubated OHCs was not different from those fixed with GA. The present data provide a rational basis for isolated OHC shape parameters. Moreover, functionally induced changes can be better interpreted when OHCs are influenced by fixatives, as shown in the GA experiments. 相似文献
79.
Summary A congenital human teratoma contained a neuroectodermal mass with architectonic features similar to those of the normal developing neo-cortex. Surrounding a central cavity, a germinal, an intermediate and a cortical zone were clearly distinguishable from innermost to outermost. Glial fibers coursed radially through the intermediate and cortical zones. In the cortical plate neuronal elements were oriented radially with an inside out gradient of differentiation. Mesothelial tissue covered the outer surfaces of the cortex. Over limited sectors a gap in the integrity of the meso-glial barrier were associated with neuroglial ectopias.The following points are of neurobiologic importance: the formation of the miniature cerebral cortex occurred in the absence of any influence of afferent subcortical fibers. The radial alignment of glial fibers between the germinal pseudostratified epithelium and the outer surface occurred only in sectors of the neuro-ectodermal mass where a neo-cortex was present, and may therefore have been a critical determinant in the formation of the cortical plate. The integrity of the outer glial mesenchymal barrier may be necessary for the normal arrangement of cortical neurons. 相似文献
80.
Carlo Orzincolo M.D. Pier Nuccio Scutellari M.D. Giuseppe Castaldi M.D. 《Skeletal radiology》1992,21(1):39-44
In 12 patients affected by thalassemia major who received an intensive transfusion regimen combined with continuous iron chelation therapy (desferrioxamine 50–80 mg/kg daily), radiologic abnormalities of the long bones were observed similar to those observed in rickets and scurvy. These abnormalities were associated with a growth retardation. The pathogenesis of these lesions is uncertain, but probably the toxic effect of desferrioxamine plays an important role in their development. A relative deficiency of vitamins D and/or C cannot be entirely excluded. 相似文献