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81.
BG Russell WE Moddeman JC Birkbeck SE Wright DS Millington RD Stevens KE Dombrowski 《Canadian Metallurgical Quarterly》1998,4(4):257-266
The stimulating effect of antiparkinsonian drugs, talipexole and bromocriptine, on the striatal postsynaptic dopamine receptors were studied by measuring contralateral rotational behavior in rats. The nigro-striatal dopamine system of rats was degenerated by unilateral injection of 6-hydroxydopamine (6-OHDA, 8 micrograms/rat) into substantia nigra. By subcutaneous administration, talipexole at 0.16 mg/kg and bromocriptine at 10.24 mg/kg induced significantly increased rotational behavior to the contralateral direction to the lesioned side. The onset of the effect was 30 min for talipexole and 90 min for bromocriptine. By intragastric administration, talipexole at 0.4 mg/kg and bromocriptine at 20.48 mg/kg significantly increased the rotational behavior, and the onset of the effect was 60 min for talipexole and 180 min for bromocriptine. Rotational behavior induced by talipexole was suppressed by a D2 antagonist, sulpiride (40 mg/kg, s.c.), but not by a D1 antagonist, SCH23390 (1 mg/kg, s.c.). In contrast, rotational behavior induced by bromocriptine was suppressed by both sulpiride and SCH23390. These results indicated that when the nigrostriatal dopaminergic functions are disrupted, talipexole stimulates the striatal postsynaptic dopamine receptors at much lower doses than bromocriptine. Also it was indicated that the stimulating effect of talipexole is solely mediated by dopamine D2 receptors, whereas the effect of bromocriptine is mediated by both D1 and D2 receptors. 相似文献
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83.
Osteotomy is the well-established treatment of Blount's disease (tibia vara), although the types of fixation used vary considerably. The use of dynamic axial external fixation to stabilize osteotomies for tibia vara until solid union occurs without the use of supplemental casting has not been reported by other authors. From 1985 until the present, we have used osteotomy with dynamic axial external fixation as treatment of 31 tibiae in 23 patients. All osteotomies healed and there was no postoperative loss of correction. There was an average correction of 20 degrees between the pre- and postoperative mechanical axis. Advantages of dynamic axial external fixation include ease of application, adjustability, early weight bearing, the ability to lengthen the extremity, and no second operation for removal of hardware. Based on our results, we believe that dynamic axial external fixation is an excellent form of osteotomy stabilization in the surgical treatment of tibia vara. 相似文献
84.
SB Christensen A Guider CJ Forster JG Gleason PE Bender JM Karpinski WE DeWolf MS Barnette DC Underwood DE Griswold LB Cieslinski M Burman S Bochnowicz RR Osborn CD Manning M Grous LM Hillegas JO Bartus MD Ryan DS Eggleston RC Haltiwanger TJ Torphy 《Canadian Metallurgical Quarterly》1998,41(6):821-835
Evaluation of a variety of PDE4 inhibitors in a series of cellular and in vivo assays suggested a strategy to improve the therapeutic index of PDE4 inhibitors by increasing their selectivity for the ability to inhibit PDE4 catalytic activity versus the ability to compete for high affinity [3H]rolipram-binding sites in the central nervous system. Use of this strategy led ultimately to the identification of cis-4-cyano-4-[3-(cyclopentyloxy)-4-methoxyphenyl]cyclohexane-1-carboxyl ic acid (1, SB 207499, Ariflo), a potent second-generation inhibitor of PDE4 with a decreased potential for side effects versus the archetypic first generation inhibitor, (R)-rolipram. 相似文献
85.
RH Swerdlow JK Parks JN Davis DS Cassarino PA Trimmer LJ Currie J Dougherty WS Bridges JP Bennett GF Wooten WD Parker 《Canadian Metallurgical Quarterly》1998,44(6):873-881
Recent data suggesting complex I dysfunction in Parkinson's disease (PD) arises from mitochondrial DNA (mtDNA) mutation does not conclusively answer whether the responsible genetic lesion is inherited (primary) or somatic (secondary). To address this question, we identified a family in which multiple members over three generations are affected with PD through exclusively maternal lines. Cytoplasmic hybrids (cybrids) were created for 15 family members over two generations by transferring each individual's mtDNA to mtDNA-depleted human neuroblastoma cells. Eight of the 15 cybrid lines contained mtDNA obtained from maternally descended family members and seven contained mtDNA from paternally descended family members. After 6 weeks of culture, cybrid cell lines were assayed for complex I activity and oxidative stress, and mitochondrial morphology was analyzed by electron microscopy. Compared with the cybrid lines containing mtDNA from paternal descendants, cybrid lines containing mtDNA from maternal descendants had lower complex I activity, increased reactive oxygen species production, increased radical scavenging enzyme activities, and more abnormal mitochondrial morphologic features. These findings were present in cybrid lines containing mtDNA from maternal descendants with PD as well as in currently asymptomatic young maternal descendants, and support a precedent for inherited mtDNA mutation in some persons with PD. 相似文献
86.
DS Khalsa 《Canadian Metallurgical Quarterly》1998,4(6):38-43
This article, based on scientific research and clinical observations, suggests that memory loss is not an inevitable consequence of aging and that Alzheimer's disease can be prevented and reversed using an integrated medical approach. Three new associations with memory loss other than age, heredity, and genetics are described. They include a high-fat diet, chronic unbalanced stress with its attendant risk in the adrenal hormone cortisol, and the presence of cardiovascular disease. A 4-pillar integrative medical program on brain longevity is presented. The program includes a diet consisting of 15% fat and supplementation with brain-specific nutrients such as vitamin B complex, vitamin E, ubiquinone, ginkgo biloba, and phosphatidylserine. In addition, stress-relieving meditation, mind-body and cognitive exercise, antiaging drugs like L-deprenyl citrate, as well as hormones such as dehydroepiandrosterone and pregnenolone complete the program. Patient benefits such as greater wisdom and spiritual happiness are also explored. 相似文献
87.
YJ Chwae IH Choi DS Kim EC Shin DH Kwon SJ Kim JD Kim 《Canadian Metallurgical Quarterly》1998,63(3):147-152
Videolaparoscopic cholecystectomy is considered the treatment of choice for simple cholelithiasis. Now many surgeons consider the laparscopic procedure usable also in the complicated biliary lithiasis like acute cholecystitis and choledocholithiasis. The authors report their recent experience of the laparoscopic treatment of biliary lithiasis, regarding 221 non-selected patients (69% symptomatic cholelithiasis, 20% chronic cholecystitis, 4.5% acute cholecystitis, 4.5% coledocolithiasis, 2% hydrops). The diagnostic-therapeutic protocol and the results are described and compared with the beginning of their experience, when they treated only symptomatic gallbladder stone disease, and with the reports of the literature. The authors concluded that the laparoscopic procedure is a good chance for the surgeon in the treatment of all cases of benign biliary disease. But, in particular for patients with choledocholithiasis, he has be able to know all the diagnostic and therapeutic possibilities, to choose the best in every single case. 相似文献
88.
v-raf suppresses apoptosis and promotes growth of interleukin-3-dependent myeloid cells 总被引:1,自引:0,他引:1
JL Cleveland J Troppmair G Packham DS Askew P Lloyd M González-Garcia G Nu?ez JN Ihle UR Rapp 《Canadian Metallurgical Quarterly》1994,9(8):2217-2226
Interleukin-3 (IL-3) is required for the proliferation, survival and differentiation of myeloid progenitors. In the absence of IL-3, murine myeloid 32D.3 cells accumulate in the G1 phase of the cell cycle and subsequently undergo programmed cell death, or apoptosis. Here we demonstrate that enforced expression of the v-raf oncogene suppresses apoptosis of myeloid 32D.3 cells following the withdrawal of IL-3. Surprisingly, steady state levels of Bcl-2, an oncogene known to suppress apoptosis, were not dependent upon IL-3 in 32D.3 cells and its levels were not augmented in v-raf clones. This suggests that ability of v-raf to suppress apoptosis in the absence of ligand is either Bcl-2 independent or that v-raf kinase promotes Bcl-2 function. v-raf also promoted growth of these cells in the presence of IL-3. v-raf clones proliferated at an increased rate due to a shortened G1 phase and had decreased requirements for IL-3 for growth. Therefore, transformation of myeloid cells by v-raf involves signaling pathways which promote both cell cycle progression and cell survival. 相似文献
89.
90.