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排序方式: 共有4520条查询结果,搜索用时 15 毫秒
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Spinal antinociceptive effects of adenosine compounds in mice 总被引:1,自引:0,他引:1
The effects of injecting ATP, ADP, AMP, adenosine and adenine intrathecally on the pain response induced by the injection of substance P (10 ng/mouse) intrathecally were studied. All the compounds except adenine inhibited the pain response in a dose-related manner. The ED50 values of ATP, ADP, AMP and adenosine were 2.10, 0.93, 0.88 and 0.48 micrograms/mouse, respectively. Pretreatment with theophylline at a dose of 100 mg/kg p.o. markedly diminished all the antinociceptive effects. The effect of adenosine was not affected by s.c. injection of naloxone. These results suggest the existence of adenosine receptors which modulate spinal nociceptive sensory processing, independently of the endogenous opiate system. 相似文献
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B F Trump T W Jones K A Elliget M W Smith P C Phelps A Maki I K Berezesky 《Renal failure》1990,12(3):183-191
Cellular toxicity and cellular carcinogenesis are closely linked. In the kidney, this relationship has been emphasized by the recent discovery of a number of putatively non-mutagenic chemicals that result in acute and chronic toxicity and ultimately in carcinogenesis, especially in the male rat. Many, but not all such compounds, result in renal PTE phagolysosomal overload. At the same time, known metabolites of other carcinogens, e.g., HCBD and FBPA, result in acute renal injury and/or necrosis, followed by chronic tubular disease, interstitial nephritis, and ultimately carcinogenesis. A series of cell mechanisms have been suggested that lead from acute cell injury to altered control of cell division. These mechanisms appear to involve ion deregulation, (especially [Ca2+]i) resulting from a variety of continued injuries, (e.g., oxidative stress from inflammatory cells) and ultimately leading to altered gene expression. 相似文献
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Performance standards for toric soft contact lenses. 总被引:1,自引:0,他引:1
Jacqueline Tan Eric Papas Nicole Carnt Isabelle Jalbert Cheryl Skotnitsky Maki Shiobara Edward Lum Brien Holden 《Optometry and vision science》2007,84(5):422-428
PURPOSE: To simplify the clinical assessment of toric soft contact lens (TSCL) on-eye behavior by establishing a set of standard clinical evaluation techniques. The likely performance range expected among the TSCL wearing population was determined for a series of lens designs and acceptable performance standards indicated for each variable. METHODS: Four prism-ballast, two peri-ballast and one dynamic stabilization TSCL designs were each worn by groups of 20 subjects in a nondispensing study. After 20 min of lens wear, lenses were assessed, in right eyes only, for subjective comfort (100-point scale), lens mislocation (degrees deviation from vertical) and rotational recovery after deliberate 30 degrees mislocation (degrees/10 blinks). The percentage of lenses orienting within +/-10 degrees of target orientation (zero rotation) and the variability of orientation (standard deviation of mislocation) were also calculated for each lens group. RESULTS: Based on partitioning of the data distributions for each variable, performance was designated as excellent, acceptable or poor. Corresponding performance cut-offs were determined at > or =90, 89 to 80, and <80 for subjective comfort, < or =+/-6 degrees , +/-7 degrees to 10 degrees , and >+/-10 degrees for mislocation, >10 degrees /10 blinks, 10 degrees to 6 degrees /10 blinks, and <6 degrees /10 blinks for rotational recovery. For groups of wearers the appropriate cut-offs were > or =90%, 89 to 70%, and <70% of lenses orienting within +/-10 degrees of target orientation and <+/-6 degrees , +/-6 degrees to 10 degrees , and >+/-10 degrees for variability of orientation. CONCLUSION: Techniques suitable for the evaluation of TSCL clinical performance have been described and guidelines for the assessment of such lenses established. In the process, we have identified potential performance differences that may relate to variations in TSCL design. 相似文献
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S Maki 《Fukuoka igaku zasshi》1991,82(2):86-99
When the anteromedial hypothalamus is stimulated with a chronically implanted electrode in conscious cats, negative emotional behaviors such as restlessness and escape occur during stimulation and ventricular extrasystoles occur in rapid succession immediately after the end of stimulation. It has been shown in the lightly anesthetized cat that the activity of the sympathetic nervous system becomes predominant during stimulation of the anteromedial hypothalamus thereby causing the rises in blood pressure and heart rate. However, immediately after the cessation of the stimulation, this 'sympathetic dominant' state was observed to be switched to the 'parasympathetic dominant' state with falls in blood pressure and heart rate which was very frequently followed by the appearance of the ventricular extrasystoles (Poststimulus Arrhythmia: PSA). The purpose of this experiment was to examine how the electric and pharmacological stimulation of the prefrontal cortex modulate the rise in the blood pressure and heart rate and PSA caused by electric stimulation of the anteromedial hypothalamus. When the prefrontal cortex was electrically stimulated simultaneously with stimulation of the anteromedial hypothalamus in 24 lightly anesthetized cats, PSA was inhibited or facilitated or remained unchanged depending on the site of stimulation in the prefrontal cortex. When dopamine or noradrenaline was microinjected into the site of prefrontal cortex where PSA was inhibited, PSA was suppressed and this effect was blocked by microinjection of haloperidol or phenoxybenzamine, respectively. Dopamine was ineffective when injected in the site where PSA was facilitated; PSA was facilitated by microinjection of noradrenaline and this effect was inhibited by microinjection of propranolol. Although changes in blood pressure and heart rate were observed when the inhibition or facilitation of PSA was elicited by prefrontal injection of noradrenaline, no changes in cardiovascular parameters occurred when dopamine injection caused the inhibition of PSA. These results suggest (1) that activation of the dopamine receptor or alpha adrenoceptor in the prefrontal cortex is involved in the inhibition of PSA, and activation of beta adrenoceptor is concerned with facilitation of PSA and (2) that the mechanisms of dopamine receptor mediated inhibition of PSA appear to be different from those of inhibition of PSA by activation of the alpha adrenoceptor in the prefrontal cortex. 相似文献
8.
M Maki T Terao T Ikenoue T Takemura K Sekiba K Shirakawa H Soma 《Gynecologic and obstetric investigation》1987,23(4):230-240
Antithrombin III (AT III) is known to be the most important inhibitor of serine protease in the coagulation system. In the presence of heparin, AT III is converted from its progressive activity state to an immediate activity state. In disseminated intravascular coagulation (DIC) in the field of obstetrics, the treatment has to be initiated very early. Heparin treatment, on the other hand, is critical since frequently postpartal or postoperative wound bleeding is present. We, therefore, established diagnostic criteria for the early diagnosis of DIC and investigated the clinical efficacy of a therapy with AT III in a well-controlled comparative study versus the injectable synthetic protease inhibitor FOY. The results of the trial showed that the AT III group (92%; n = 24) was significantly (p less than 0.001) superior in clinical efficacy to the FOY group (60%; n = 15). No side effects whatsoever were observed after treatment with AT III concentrate (Behring Institute). From these results, it could be concluded that a single therapy with AT III concentrate can sufficiently control the symptoms of DIC in the field of obstetrics without the risk of increased bleeding. 相似文献
9.
Ken Yamaguchi Katsumi Aoyagi Ken-ichi Urakami Toyoharu Fukutani Noboru Maki Shigehiro Yamamoto Kotomi Otsubo Yoshio Miyake Tetsuro Kodama 《Cancer science》1995,86(7):698-705
Our previous study demonstrated that pro-gastrin-releasing peptide(31–98), or ProGRP, is a specific tumor marker in patients with small cell lung carcinoma (SCLC). Using a newly developed, highly sensitive enzyme-linked immunosorbent assay (ELISA) for ProGRP, we analyzed 1,446 samples including those obtained from 478 lung cancer patients to evaluate the clinical usefulness of this ELISA. Several properties indicated that ProGRP is a useful tumor marker for SCLC. First, ProGRP was specifically elevated in SCLC patients. In non-SCLC patients and patients with non-tumorous lung diseases, its serum level was very rarely elevated. Secondly, ProGRP was a reliable marker, in terms of the marked elevation of serum ProGRP levels in SCLC patients. Thirdly, serum ProGRP levels were elevated in SCLC patients even at a relatively early stage of this disease. Fourthly, changes in the serum ProGRP level showed an excellent correlation with the therapeutic responses in SCLC patients. Neuron-specific enolase (NSE) is accepted as a tumor marker of SCLC patients. With the aim of comparing ProGRP and NSE as tumor markers for SCLC patients, we measured serum NSE levels in all samples collected in the present study. We found that ProGRP was superior to NSE in terms of sensitivity, specificity and reliability. Therefore, we consider that ProGRP can play a major role as a clinical tumor marker for SCLC patients. 相似文献
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