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51.
在RPHI试验中,将VitK1或VitK3预先与HBsAg阳性血清作用后,再加抗HBs单克隆抗体诊断红细胞,可见红细胞呈圆点状沉淀,提示HBSAg与抗HBs的结合受到抑制,该抑制作用呈浓度依赖性.RPHI试验后的抗HBs单克隆抗体诊断红细胞,经洗涤后再与HBsAg阳性血清作用,仍出现明显凝集,表明VitK对HBsAg与抗HBs结合的抑制作用不是通过影响抗HBs而产生的。 相似文献
52.
An innocuous sensory event (a prestimulus) that briefly precedes a startle-eliciting stimulus (SES) will reduce the amplitude
of the subsequently elicited reflex. In three experiments brief silent periods in otherwise continuous noise (gaps) were used
as prestimuli to investigate the effects of the D1 dopamine receptor agonist (±)-SKF-38393 (SKF) and the dopamine D2 receptor group agonist (−)-quinpirole hydrochloride on gap inhibition of the rat’s acoustic startle reflex. Gap durations
of 4 and 50 ms were analyzed. Quinpirole (0–1.6 mg/kg) had a biphasic effect on gap inhibition. Lower doses increased gap
inhibition, an effect that peaked at the 0.4 mg/kg dose. For higher doses, inhibition returned to control levels for the 4-ms
long gap, but remained elevated for the 50-ms long gap. SKF had no effect on gap inhibition, and haloperidol (0.2 mg/kg) reversed
the quinpirole-induced increase of gap inhibition. These data implicate the D2 dopamine receptor group in gap inhibition of startle modulation. The results are discussed in terms of the effects of catecholamine
agonists on attention.
Received: 25 July 1995/Final version: 28 April 1997 相似文献
53.
Jaroslav Salamoun Jo
rg Remien 《Journal of pharmaceutical and biomedical analysis》1992,10(10-12):931-936
The inhibiting compounds were separated by micro-column liquid chromatography in the mobile phase containing the natural substrate acetylcholine. A home-made packed bed microbioreactor system containing immobilized enzyme acetylcholinesterase (ACHE) in human red blood cell membrane and choline oxidase (CHO) from alcaligenes was used for the post-column conversion of acetylcholine to hydrogen peroxide which was detected by an electrochemical detector. The inhibition effect of the solutes caused a decrease in the acetylcholinesterase activity, a decrease in the formation of hydrogen peroxide and also a decrease in the response corresponding to the concentration of the solutes. The rate of the enzyme regeneration was also recorded. The micro-system was compared with a conventional LC system comprising commercially prepared enzyme reactor. The stability of the enzymes is at least 3 weeks at ambient temperature. The limit of detection depends on biological activity of inhibition and for galanthamine was 1 pmol. 相似文献
54.
S. Gasic G. Heinz C. Kleinbloesem 《Naunyn-Schmiedeberg's archives of pharmacology》1990,342(4):436-440
Summary The renin-angiotensin system relevantly contributes to the maintenance of systemic vascular tone and there is experimental evidence that large amounts of angiotensin-converting enzyme (ACE) are present in peripheral vascular tissues, including resistance vessels. To determine and quantify peripheral vascular conversion of angiotensin-I (ANG-I) to angiotensin-II (ANG-II) across the human leg, the response of regional blood flow to local regional intra-arterial infusion of ANG-I and changes in associated ANG-I1 balance were evaluated during ANG-I infusion and following additional ACE inhibition. Ten sodium-loaded healthy men were enrolled in the study. Following cannulation of both femoral arteries and the right femoral vein, leg blood flow was determined (indocyanine-green dye-dilution method) at baseline conditions and during constant intra-arterial infusion of haemodynamically ineffective doses of ANG-I as well as following concomitant intra-arterial administration of low doses of the non-sulfhydril ACE inhibitor cilazapril. From the transfemoral arterio-venous differences in ANG-II plasma concentrations and the corresponding regional blood (plasma) flow, the ANG-II balance across the leg was calculated. Systemic blood pressure did not change throughout the trial, indicating that no major systemic effects were present during ANG-I infusion or concomitant ACE inhibition. Moreover, arterial ANG-II plasma concentrations were not significantly changed by ANG-I infusion. Leg blood flow decreased to below baseline values following ANG-I infusion, increasing again then in a dose-dependent manner during concomitant cilazapril administration. The calculated baseline ANG-II balance across the leg revealed a net extraction in 6 out of 10 subjects and a net ANG-II formation in 4. Following ANG-I, a shift towards net ANG-II formation or decrease in extraction was seen in 8 subjects, while 2 had no change in ANG-II balance.During concomitant ACE inhibition, ANG-II balance was again shifted towards net extraction or reduced formation. Our results confirm that, in man, considerable regional arterio-venous differences in ANG-II plasma concentrations are present, resulting in either net transfemoral extraction or net formation of the peptide. It is suggested that systemic vascular conversion of circulating ANG-I might contribute to the maintenance of peripheral vasuclar tone in man.
Send offprint requests to S. Gasic at the above address 相似文献
55.
Takashi Ito Ryuji Sakakibara MD Tatsuya Yamamoto Tomoyuki Uchiyama Zhi Liu Masato Asahina Morihiro Higashi Kimihito Arai Shoichi Ito Yusuke Awa Kaori Yamamoto Mika Kinou Tomonori Yamanishi Takamichi Hattori 《Clinical autonomic research》2006,16(1):66-71
Abstract Uro-neurological assessment was performed in four patients with small-fiber neuropathy due to amyloidosis (2 transthyretin-type/2
immunoglobulin light-chain-type). Voiding difficulties were due to detrusor weakness and impaired bladder sensation. In two
patients cholinesterase inhibition treatment caused urge incontinence, indicating detrusor denervation supersensitivity. The
underlying mechanisms of urinary dysfunction seem to involve postganglionic cholinergic and afferent somatic nerves. 相似文献
56.
H. Noguchi M. Ueda Y. Nakai Y. Iwanaga T. Okitsu H. Nagata Y. Yonekawa N. Kobayashi T. Nakamura H. Wada S. Matsumoto 《American journal of transplantation》2006,6(3):496-504
Islet allotransplantation can achieve insulin independence in patients with type I diabetes. Recent reports show that the two-layer method (TLM), which employs oxygenated perfluorochemical (PFC) and UW solution, is superior to simple cold storage in UW for pancreas preservation in islet transplantation. However, UW solution has several disadvantages, including the inhibition of Liberase activity. In this study, we investigated the features of a new solution, designated M-Kyoto solution. M-Kyoto solution contains trehalose and ulinastatin as distinct components. Trehalose has a cytoprotective effect against stress, and ulinastatin inhibits trypsin. In porcine islet isolation, islet yield was significantly higher in the M-Kyoto/PFC group compared with the UW/PFC group. There was no significant difference in ATP content in the pancreas between the two groups, suggesting that different islet yields are not due to their differences as energy sources. Compared with UW solution, M-Kyoto solution significantly inhibited trypsin activity in the digestion step; moreover, M-Kyoto solution inhibited collagenase digestion less than UW solution. In conclusion, the advantages of M-Kyoto solution are trypsin inhibition and less collagenase inhibition. Based on these data, we now use M-Kyoto solution for clinical islet transplantation from nonheart-beating donor pancreata. 相似文献
57.
Cesare Mondadori Conrad Gentsch Bastian Hengerer Thomas Ducret Jürgen Borkowski Amy Racine Renate Lederer Albert Haeusler 《Psychopharmacology》1992,109(4):383-389
Oral pretreatment with aldosterone or corticosterone blocked the memory-enhancing effects of the calcium antagonist nimodipine, the ACE inhibitor captopril, the NMDA blocker CGP 37 849, and the glycine antagonist strychnine in a passive-avoidance test in mice. The memory-disturbing effects of phenobarbitone, diazepam, CGP 37 849 and scopolamine were not influenced by the hormonal pretreatment. These findings could indicate the involvement of a steroid-sensitive mechanism in drug-induced improvement of memory. In the light of clinical observations showing elevated cortisol levels in Alzheimer patients, the results might also explain why only a limited number of these patients respond to therapy with memory enhancers. 相似文献
58.
A brief mechanical or electrical stimulus to peripheral nerve afferents from the upper and lower limbs elicited a small and inconsistent EMG response of the orbicularis oculi muscles. This response was facilitated when the stimuli were delivered at fixed leading time intervals, of 45–300 ms, with respect to a supraorbital nerve electrical stimulus. Also, the peripheral nerve stimulus modified the conventional blink reflex responses, inducing facilitation of R1 and inhibition of R2. These results suggest a complex processing of sensory inputs from the face and the limbs at the brainstem, where they are probably integrated in a network of interneurons influencing the excitability of facial motoneurons. 相似文献
59.
P. E. Lønning M. Dowsett A. Jones D. Ekse S. Jacobs F. McNeil D. C. Johannessen T. J. Powles 《Breast cancer research and treatment》1992,23(1-2):57-62
Summary The clinical and biochemical effects of combined treatment with the two aromatase inhibitors aminoglutethimide and 4-hydroxyandrostenedione were evaluated in 10 patients suffering from advanced breast cancer. All patients had become resistant to treatment with one of the drugs before having combined treatment. Seven patients progressing on 4-hydroxyandrostenedione who had aminoglutethimide added to their treatment and achieved a further suppression of plasma oestradiol by a mean of 40.0% (p<0.05). Plasma oestrone was suppressed by a mean of 40.6% (p<0.025) and plasma oestrone sulphate was suppressed by a mean of 63.6% (p<0.025). Two of the patients, neither of whom had responded to 4-hydroxyandrostenedione alone, experienced objective tumour regression when aminoglutethimide was given in concert. Three patients progressing on aminoglutethimide who had 4-hydroxyandrostenedione added showed no further suppression of their plasma oestrogen levels, and no tumour regression was observed. These findings suggest a dose-response relationship between plasma oestrogen suppression at low postmenopausal levels and objective tumour response in breast cancer. 相似文献
60.
Dr C. J. Whitters T. W. Macfarlane D. Mackenzie H. Moseley R. Strang 《Lasers in medical science》1994,9(4):297-303
Pulsed Nd-YAG laser irradiation of bacteria has been suggested as a possible means of treating contaminated intra-oral sites
although relatively few studies have been conducted. In this investigation, the antimicrobial activity of a pulsed Nd-YAG
laser was assessed in vitro for a range of oral bacteria using several pulse energies and exposure durations. Pure cultures
of each organism were lased in saline suspensions followed by standard colony counting techniques for test and control samples.
Microbial inhibition was found to be organism-dependent and varied with energy dose and pulse energy. For all nine test species
120-mJ laser pulses proved more efficient than 80-mJ pulses, with 99.9% kills compared with around 90% kills after exposure
to 1800 pulses. These killing activity levels compare favourably with those achieved with other lasers in vitro. 相似文献