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61.
PURPOSE: Our objective was to evaluate the feasibility of early resumption of ambulation 3 hours after transfemoral angiography using a 4 French sheath. SUBJECTS AND METHODS: This prospective study was carried out in a selected group of men and women without impaired blood clotting (prothrombin time > 15 sec) or thrombocytopenia (platelet < 55,000/mm3). The subjects consisted of 66 men and 34 women with a mean age of 62.3 years (range 27-90 years). Incidences of rebleeding or hematoma at the site of femoral catheter insertion were investigated before and after ambulation. Rebleeding was defined as bleeding that required recompression. Hematoma was defined as a palpable, firm collection of subcutaneous blood. RESULTS: Of 100 patients who resumed full ambulation after three hours of bed rest, none (0%) had acute groin hematoma and only three (3%) showed rebleeding that had to be manually compressed. The remaining 97 patients (97%) had no problem after ambulation. CONCLUSION: Supervised resumption of ambulation 3 hours after angiography with a 4 French sheath is safe and feasible in most ambulatory patients undergoing transfemoral angiography.  相似文献   
62.
PURPOSE: To compare a multishot echo-planar fluid-attenuated inversion-recovery (EPI-FLAIR) sequence with fast spin-echo FLAIR (F-FLAIR) and fast spin-echo T2-weighted (FSE-T2W) sequences in depiction of white matter lesions. METHODS: Thirty-five patients with various white matter lesions were included in this prospective study. Two independent readers for lesion detection (lesion size, >2 mm) compared sequences quantitatively. In 22 patients, contrast was calculated between periventricular hyperintensity (PVH) and the cerebrospinal fluid (CSF). RESULTS: EPI-FLAIR revealed more lesions than FSE-T2W (p < 0.01). However, F-FLAIR revealed more lesions than EPI-FLAIR (p < 0.01). For PVH-to-CSF contrast, EPI-FLAIR demonstrated significantly higher contrast than FSE-T2W. There were no differences in PVH-to-CSF contrast between EPI-FLAIR and F-FLAIR. CONCLUSIONS: This study shows that EPI-FLAIR has distinct advantages over FSE-T2W in the depiction of white matter lesions. Although EPI-FLAIR reduces imaging time by more than 60% relative to F-FLAIR, it cannot replace F-FLAIR for the detection of lesions in the cerebral white matter.  相似文献   
63.
Protobothrops (formerly Trimeresurus) elegans, a Crotalinae snake, inhabits Ishigaki and Iriomote islands of the Sakishima Islands of Japan which are located between Okinawa island of Japan and Taiwan. Two phospholipase A(2) (PLA(2)) isozymes were purified to homogeneity from P. elegans venom and sequenced. This led to a discovery of novel PLA(2) isozymes with Arg at position 49, that is, [Arg(49)]PLA(2) forms, named PeBP(R)-I and PeBP(R)-II. They are polymorphic at position 3, Val for PeBP(R)-I and Ile for PeBP(R)-II. The cDNAs encoding PeBP(R)-I and PeBP(R)-II were cloned. The cDNA encoding an [Asp(49)]PLA(2) named PePLA(2) was also obtained. In contrast to PLA(2) isozymes from Protobothrops genus with 122 amino acid residues, PeBP(R)-I and PeBP(R)-II are composed of 121 amino acid residues due to lack of Pro at position 90. They exhibited necrotic and edema-inducing activities but no hemorrhagic activity was detected. A phylogenetic tree constructed for venom PLA(2) isozymes of Protobothrops genus and of related genera in the southwestern islands of Japan and Taiwan revealed that PeBP(R)-I and PeBP(R)-II of P. elegans are evolutionarily much closer to PmK49PLA(2), a [Lys(49)]PLA(2), from P. mucrosquamatus (Taiwan) than BPI and BPII, both [Lys(49)]PLA(2) forms, from P. flavoviridis (Amami-Oshima and Tokunoshima islands of Japan). Such evolutionary relationships are also seen in neutral [Asp(49)]PLA(2) isozymes from the three Protobothrops species. Thus, P. elegans is the species much closer to P. mucrosquamatus than P. flavoviridis. Their evolutionary distances seem to be well related to geological history of the islands where they have lived. In addition, it was clearly noted that Ovophis okinavensis (Amami-Oshima), which had formerly belonged to the Trimeresurus genus, and Trimeresurus stejnegeri (Taiwan) are the species fairly distant from Protobothrops genus.  相似文献   
64.
65.
Background: It has been reported previously that norepinephrine, when applied to the spinal cord dorsal horn, excites a subpopulation of dorsal horn neurons, presumably inhibitory interneurons. In the current study, the authors tested whether norepinephrine could activate inhibitory interneurons, specifically those that are "GABAergic."

Methods: A transverse slice was obtained from a segment of the lumbar spinal cord isolated from adult male Sprague-Dawley rats. Whole-cell patch-clamp recordings were made from substantia gelatinosa neurons using the blind patch-clamp technique. The effects of norepinephrine on spontaneous GABAergic inhibitory postsynaptic currents were studied.

Results: In the majority of substantia gelatinosa neurons tested, norepinephrine (10-60 [mu]M) significantly increased both the frequency and the amplitude of GABAergic inhibitory postsynaptic currents. These increases were blocked by tetrodotoxin (1 [mu]M). The effects of norepinephrine were mimicked by the [alpha]1-receptor agonist phenylephrine (10-80 [mu]M) and inhibited by the [alpha]1-receptor antagonist WB-4101 (0.5 [mu]M). Primary-afferent-evoked polysynaptic excitatory postsynaptic potentials or excitatory postsynaptic currents in wide-dynamic-range neurons of the deep dorsal horn were also attenuated by phenylephrine (40 [mu]M).  相似文献   

66.
To explore the relationship between mutant p53 and Pgp expression, we have examined the levels of both proteins in human colorectal adenocarcinomas. Serial frozen sections of 40 surgical samples were stained with an anti-Pgp (MRK16) and two different anti-p53 protein antibodies (Abs), PAb421 and Pabl80l. Nineteen (47.5%) of 40 samples examined were positive for Pgp, and 18 (45%) of 40 were positive for p53. The samples that stained positively with PAb421 also stained positively with Pahl80l. Pgp expression was detected in 13 (76.5%) of 17 samples that were positive for p53 using PAb421 and in 15 (83.3%) of 18 samples that were positive for p53 using Pabl80. Thus, we found that p53 and Pgp were co-expressed in a significant number of samples ( P < 0.002). There was no relationship between Pgp or p53 protein accumulation and histologic grade or stage. The present results demonstrate that Pgp expression is closely associated with p53 protein accumulation in human colorectal cancers. These data provide evidence to support the idea that mutant p53 activates the MDR1 gene in vivo .  相似文献   
67.
Role of cyclooxygenases in angiogenesis   总被引:5,自引:0,他引:5  
Angiogenesis is the process by which new blood vessels are formed. This process supports normal physiology as well as contributes to progression of disease. Progressive rheumatoid arthritis and growth of tumors are two pathologies to which angiogenesis contributes. In arthritis, we know that prostaglandins (PGs) and the enzyme cyclooxygenase-2, which catalyses prostaglandin production, are inflammatory mediators. These mediators are involved in rheumatoid arthritis and cancer-induced angiogenic processes. We discuss, herein, recent findings on the expression of cyclooxygenases in both rheumatoid arthritis and human cancer, and the links between COX-2, PGs, and angiogenesis. We also propose a model for the possible mechanistic interaction of the various cell types involved in angiogenesis.  相似文献   
68.
69.
Fluorescence resonance energy transfer (FRET) with green fluorescent protein (GFP) variants has become widely used for biochemical research. In order to expand the choice of fluorescent range in FRET analysis, we designed various color versions of the FRET-based probes for caspase activity, in which the substrate sequence of the caspase was sandwiched by donor and acceptor fluorescent proteins, and studied the potential of these color versions as fluorescent indicators. Six color versions were constructed by a combination of cyan fluorescent protein (CFP), GFP, yellow fluorescent protein (YFP), and DsRed. Real-time monitoring in single cells revealed that all probes could detect caspase activation during tumor necrosis factor (TNF)-alpha-induced cell death as a fluorescent change. GFP-DsRed and YFP-DsRed were as sensitive as CFP-YFP, and CFP-DsRed also showed a large fluorescent change. By using two probes, CFP-DsRed and YFP-DsRed, we carried out simultaneous multi-FRET analysis and revealed that the initiator- and effector-caspases were activated almost simultaneously in TNF-alpha-induced cell death. These findings may give experimental bases for the development of novel techniques to analyze multi-events simultaneously in single cells by using FRET probes in combination.  相似文献   
70.
Rationale Many attempts to understand ingestion have sought to clarify the control of meals. Little is known about the effects of the anorexogenic hormone leptin on meal patterning.Objective The present study sought to perform a dose–response analysis of the effects of acute central leptin administration on meal patterning using a validated, objective meal definition and to compare these results to those obtained with a previously used, subjective meal definition.Methods To validate the objective meal definition pharmacologically, the microstructural effects of the well-studied compound fenfluramine (SC 0, 1, 2, 4 mg/kg) on spontaneous nocturnal intake were determined in mature, non-deprived male Wistar rats (n=8) using a full Latin square design. The effects of intracerebroventricular leptin administration (0, 0.3, 1, 3, 6.25 g; n=10) were also examined, and perceived meal patterns obtained from the objective and subjective definitions were compared.Results Fenfluramine reduced meal size and eating rate at doses that did not reduce meal frequency or duration. In contrast, comparably anorectic doses of leptin had potent post-meal satiety-like effects, reducing meal frequency and prolonging the intermeal interval without reducing average meal size, a finding opposite to that suggested by the previously used subjective meal definition. Unlike comparably and more anorectic doses of fenfluramine, leptin non-specifically reduced both prandial and non-prandial drinking.Conclusions Acute increases in central leptin levels may potently augment post-prandial satiety and influence body-fluid homeostasis. The results reveal unappreciated central modes of action for the ob protein which qualitatively differ from the intra-meal satiating-like effects of fenfluramine.  相似文献   
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