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81.
A significant increase of cutaneous laser Doppler flowmetry was found before blood flow decreases with increasing pressure during a 5 mmHg min−1 increase of pressure strain on the finger. Pre-treatment with a local anaesthetic or chronically applied capsaicin, resulted in the disappearance of the vasodilatory response. These results suggest an original vasodilatory axon reflex response to non-noxious pressure strain which is initiated by capsaicin-sensitive nerve terminals in the human skin. 相似文献
82.
丝裂霉素C与5—Fu用于抗青光眼滤过性手术的对比研究 总被引:1,自引:0,他引:1
采用随机、双讯,前瞻对照的方法比较了丝裂霉素C(MMC)和5-氟尿嘧啶对难治性青光眼小梁切除手术的安全性和有效性。39例病人随机分成二组,一组使用MMC,另一组使用5-Fu。结果提示:(1)MMC组手术成功率高于5-Fu组;(2)MMC组角膜上皮缺损发生率,结膜创口渗漏率明显低于5-Fu组。 相似文献
83.
P. E. Light Z. Y. Sahaf S. J. Publicover 《Naunyn-Schmiedeberg's archives of pharmacology》1988,338(4):339-344
Summary The effect of the phorbol ester 12-O-tetradecanoylphorbol-13-acetate (TPA) on the release of transmitter at the frog neuromuscular junction has been investigated electrophysiologically. TPA (100 nmol/l) caused a gradual rise in miniature end-plate potential (MEPP) frequency. After 20–30 min MEPP frequency had risen by approximately 40%. This action of the drug was not inhibited by bathing preparations in either Ca2+-free medium (0 Ca2+-1 mmol/l EGTA) or high Mg2+ medium, or by pretreatment with verapamil (5 mol/l). The inactive TPA analogue 4--TPA had no effect on release rate. There was no indication of any positive correlation between resting MEPP frequency and the size of the subsequent response to TPA treatment. Any synergism between [Ca2+]i and TPA treatment is therefore likely to occur at a site other than that which determines spontaneous release rate.The stimulatory effect of TPA was enhanced 2-fold by carrying out the experiments in a partially depolarising saline (10 mmol/l K+). When TPA was applied to preparations bathed in Ca2+-free depolarising saline, the response to the drug was still significantly greater than that in non-depolarised preparations. It is concluded that responsiveness to TPA is enhanced by depolarisation, but that little, if any, of this enhancement can be attributed to the consequent influx of Ca2+.Send offprint requests to S. J. Publicover at the above addressPEL was in receipt of an S.E.R.C. postgraduate awardZYS was in receipt of financial support from Umm Al Qura University, Saudi Arabia 相似文献
84.
P. Hartvig K. J. Lindner J. Tedroff P. Bjurling K. Hörnfelt B. Långström 《Journal of neural transmission (Vienna, Austria : 1996)》1992,87(1):15-22
Summary The regional brain kinetics of (-11C)-L-dopa and 6-fluoro-(-11C)-L-dopa was measured in six Rhesus monkeys using positron emission tomography (PET). Radioactivity accumulated specifically in the striatal region and the increase in L-dopa-derived radioactivity utilization with time was calculated using surrounding brain as a reference area, this being devoid of dopaminergic activity. The rate constant for selective striatal utilization i.e. grossly decarboxylation was 0.0110 ± 0.0007 (S.D) and 0.0057 ± 0.0006 min1 for (-11C)-L-dopa and 6-fluoro-(-11C)-L-dopa, respectively. After pre-treatment of the monkeys with the peripherally and centrally active catecholamine-O-methyl transferase (COMT) inhibitor Ro 40-7592 10 mg/kg, the decarboxylation rate remained unchanged (0.0112 ± 0.0015 min-1) for (11C)-L-dopa, whereas an increase in rate was measured for 6-fluoro-(-11C)L-dopa (0.0092 ± 0.0015 min–1). Differences in the distribution of radiolabelled metabolites i.e. the corresponding O-methyl-L-dopa in the reference area is most probably the reason for the difference in calculated decarboxylation rate seen between the radiotracers. The higher decarboxylation rate measured for 6-fluoro-(-11C)-L-dopa after blockade of COMT shows that the radiolabelled metabolites i.e. 6-fluoro-O-methyl-(-11C)-L-dopa significantly contributes to background radioactivity. 相似文献
85.
Y Takamiya M P Short Z D Ezzeddine F L Moolten X O Breakefield R L Martuza 《Journal of neuroscience research》1992,33(3):493-503
Tumor cells infected with a retrovirus vector (VIK) containing the herpes simplex virus thymidine kinase (HSV-TK) gene can be selectively killed by treatment with nucleoside analogues, such as ganciclovir. To mediate delivery of the HSV-TK gene to "recipient" tumor cells, "donor" C6 rat glioma cells infected with the VIK vector (C6VIK) were superinfected with wild type Moloney murine leukemia virus (WT Mo-MLV). These modified donor cells (C6VIKWT) produced both wild type retrovirus and the VIK vector. In culture, C6VIKWT cells were 300-fold more sensitive to the toxicity of ganciclovir than were C6VIK cells, suggesting that the presence of wild type retrovirus contributed to the toxicity. Co-culture of C6VIKWT cells with the C6 subline, C6BAG, sensitized the latter to ganciclovir treatment. Nude mice inoculated subcutaneously with a mixture of C6VIKWT and C6BAG cells showed regression of subsequent tumors when treated with ganciclovir. The observations show that tumor cells modified in culture by infection with a retrovirus bearing the HSV-TK gene and wild type retrovirus are not only sensitive to ganciclovir, but can transfer this sensitivity to neighboring "naive" tumor cells in culture and in vivo. 相似文献
86.
Allegria Kessous Pierre Colombies Martine Sudries Georges Bourrouillou Jacques Pris Danielle Clement 《Cancer Genetics and Cytogenetics》1980,2(4):335-337
This report describes a new case of chronic myeloid leukemia with an unusual Philadelphia chromosome translocation involving chromosomes No. 4,9, and 22; t(4,9,22) (q31;q34;q11). 相似文献
87.
Radiotelemetry of the human EKG was obtained to observe for rate alterations during spontaneous cigarette smoking. Ten subjects were observed for a total of 26 hours during which time 50 cigarettes were smoked. The utilization of telemetry allowed the subjects to continue their usual afternoon behavior. There were no rate changes before, during, or after smoking which could be attributed to the cigarette. These results differ from most previous reports. Telemetry allows for two departures from past designs; subjects were ambulant and smoking behavior was spontaneous (both in initiation and rate). It is suggested that these departures are related to the results of the present study. 相似文献
88.
H. Keller S. Löke G. M. Hänsch D. Jentschura H. Gerhard D. L. Heene 《Journal of molecular medicine (Berlin, Germany)》1987,65(8):387-390
Summary An 18-year-old man suffered from recurrent bacterial meningitis. Investigation of the complement system revealed deficiency of the 8th complement component (C8) in the patient and his sister. Genetic defects of the terminal complement components C5 to C8 predispose toNeisseria infections, probably due to a lack in bacteriolytic activity. It is to be noted that 1 year ago the patient had been hospitalized for a culture-proved pneumococcal meningitis. 相似文献
89.
A Orozco C E Contreras P Sánchez O Meilijson N E Bianco 《Journal of immunological methods》1983,59(2):237-243
A C1q solid phase microassay was designed for the rapid detection of circulating immune complexes. Its level of sensitivity is comparable to that of the Raji cell and greater than the C1q binding assay; furthermore, it is faster and low in cost. These conditions make it more practical and applicable in the clinical setting. 相似文献
90.
Peripheral blood dendritic cells increase in kidney-transplant patients without rejection 总被引:2,自引:0,他引:2
Saresella M Marini M Guerini F Ferrante P Della Bella S Chiaramonte S Riva A 《Clinical immunology (Orlando, Fla.)》2004,110(2):191-3; author reply 194