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排序方式: 共有10000条查询结果,搜索用时 46 毫秒
991.
992.
Pyroglutamyl, proline-rich oligopeptides, classically referred to as bradykinin-potentiating peptides (BPPs) are found in Bothrops jararaca venom, and are naturally occurring inhibitors of the somatic angiotensin-converting enzyme (ACE). The chemical and pharmacological properties of these peptides were essential for the development of captopril, the first active site directed inhibitor of ACE, currently used to treat human hypertension. ACE is a complex ectoenzyme of the vascular endothelium, possessing two catalytic sites, performing diverse specific roles. Recent advances concerning novel features of BPPs revealed that they might still contribute to a better understanding of the cardiovascular physiology and pathology. The molecular biology of the BPPs revealed that they are part of two distinct C-type natriuretic peptide precursors found in the venom gland and the brain of B. jararaca, each containing seven BPPs. In situ hybridization studies detected the presence of the corresponding mRNA precursor in snake brain regions correlated with neuroendocrine functions, such as the ventro-medial hypothalamus, the paraventricular nuclei, the paraventricular organ, and the subcommissural organ. In this article we discuss the large variety of homologous BPPs in B. jararaca venom and brain, its significance, and whether the BPPs could represent novel endogenous neuropeptides. 相似文献
993.
As the biological width is established around neighboring implants, there is a flattening of the interimplant bone and a change in the position of the soft tissue. As a result, a normal progression of papilla from natural teeth through the adjacent implant area is lost. This presentation describes various techniques and strategies to improve the aesthetic outcome of anterior implant restorations, together with the use of a scalloped implant designed to sustain the interdental bony peaks, and in doing so, maintain the interimplant papillae. 相似文献
994.
Holly C Matto Jack A Naglieri 《Journal of clinical child and adolescent psychology》2005,34(4):706-711
This study examined race and ethnic differences on the Draw A Person: Screening Procedure for Emotional Disturbance (DAP:SPED; Naglieri, McNeish, & Bardos, 1991) for youths 6 though 17 years of age for 2 matched samples. Samples were drawn from the DAP:SPED nationally representative standardization sample and matched on gender, grade, and school classroom. No statistically significant differences were found for big figure, small figure, or shading item composites. A statistically significant difference was found between Black-White pairs on figure omissions but showed a small effect size (d value = .25). Further, no statistically significant differences were found between the DAP:SPED Total T scores for Black and White youth (M = 47.67, SD = 10.09; N =138) or Hispanic and White youth (M = 48.20, SD = 9.56; N = 59), showing very small effect sizes. In addition, equivalence testing showed similarities across race and ethnic pairs for all composites and DAP:SPED total score, lending preliminary support to the DAP:SPED's clinical utility as a measure that yields similar scores across these groups. 相似文献
995.
C S Letizia J Cocchiara A Lapczynski J Lalko A M Api 《Food and chemical toxicology》2005,43(6):925-943
A toxicologic and dermatologic review of cinnamic acid when used as a fragrance ingredient is presented. 相似文献
996.
The requirements, problems and progress of radioimmunotherapy in the management of certain malignancies are described. The future prospects using a two- or three-stage approach are promising. 相似文献
997.
Effects of halothane on spinal dorsal horn WDR(wide dynamic range) neuronal activity in cats 总被引:1,自引:0,他引:1
H Nagasaka S Nakamura T Genda T Miyazaki K Aikawa N Matsumoto I Matsumoto T Hori I Sato 《Masui. The Japanese journal of anesthesiology》1991,40(7):1096-1101
The effects of halothane (0.2%, 0.5%, and 1.0%) on the spinal dorsal horn wide dynamic range (WDR) neuronal activity was studied in either spinal cord intact or spinal transected cats. Extracellular activity was recorded in the dorsal horn from single WDR neurons responding to noxious and non-noxious stimuli applied to the cutaneous receptive fields on the left hind foot pads of intact or decerebrate, spinal cord transected (L 1-2) cats. When 10 micrograms of bradykinin was injected into the femoral artery ipsilateral to the recording site as the noxious test stimulus in the spinal cat, all of 7 WDR neurons gave excitatory responses which were not depressed by 0.2% and 0.5% halothane but were depressed significantly by 1.0%. On the other hand, when the injection of 10 micrograms of bradykinin into the femoral artery ipsilateral to the recording site was used in the intact cat, 7 of 14 WDR neurons (50%) gave excitatory responses, which were not depressed by 0.2% halothane but were significantly depressed by 0.5% and 1.0% halothane, and 7 of 14 WDR neurons (50%) gave inhibitory responses, which were significantly depressed by 0.2%, 0.5%, and 1.0% halothane. We have found that halothane reduces the excitation as well as the inhibition of dorsal horn WDR neuronal activity induced by bradykinin injection. 相似文献
998.
David L. Healey B.D.S. Nicholas P. Chandler B.D.S. F.D.S. F.F.D. 《The Journal of prosthetic dentistry》1991,66(6):727-729
Experiments were performed to determine the effect of pin channel preparation with standard and reduction speed handpieces, and pin seating by hand and with motor drive. The greatest retention was achieved by preparation with a standard handpiece at 6000 rpm, and manual pin placement with a hand driver. The most consistent retention values were achieved using the reduction handpiece. All preparation and placement combinations examined produced a clinically acceptable result. 相似文献
999.
J S Abramowicz S L Warsof D M Sherer D L Levy J R Woods 《Journal of ultrasound in medicine》1991,10(6):337-339
A prospective blinded study was performed on 191 high-risk patients with pregnancies ranging from 25 to 42 weeks gestation to investigate the value of a single Doppler analysis of the umbilical artery blood flow waveform (systolic-to-diastolic ratio, S/D) for predicting poor perinatal outcome. This was defined as the presence of heavy meconium, delivery of a growth-retarded infant, an umbilical cord arterial pH less than 7.2, or a 5-minute Apgar score less than 7. The interval between Doppler examination and delivery ranged from 12 hours to 15 weeks. No clinical data were available to the examiner performing the Doppler study. Moreover, the Doppler measurements were unknown to the attending physicians. The sensitivity, specificity, and positive and negative predictive values of the Doppler study in predicting outcome were 30.4%, 92.9%, 36.8%, and 92.6%, respectively, with an adverse outcome prevalence of 12%. These results indicate that a single random S/D ratio from the umbilical artery is not an adequate screening test for the risk of perinatal complications. 相似文献
1000.
L. S. Penrose 《European archives of psychiatry and clinical neuroscience》1991,240(6):315-324
Stylistic amendments to the original Penrose text have been made where necessary for further clarity 相似文献