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31.
目的:研究钕激光照射对大鼠肿瘤生长的抑制作用.方法:采用钕激光在实验组荷瘤大鼠的肿瘤区及其肿瘤区周围进行照射,并观察抑制肿瘤的效果.结果:实验组大鼠肿瘤体的生长速度明显慢于对照组大鼠肿瘤体的生长速度.结论:用钕激光照射对抑制癌肿瘤的生长速度有明显的作用. 相似文献
32.
SHILLA CHATTERJEE EUN SUNG PARK MELVYN S. SOLOFF 《International journal of urology》2004,11(10):876-884
BACKGROUND: Insulin-like growth factor binding protein-2 (IGFBP-2) is expressed by all human prostate cancer cell lines and dramatically increases in the serum of prostate cancer patients. However, the role of IGFBP-2 in prostatic tumorigenesis is not known. The aim of the present study was to investigate the effects of IGFBP-2 on the proliferation of DU145 human prostate cancer cells in culture. METHODS: Using cell proliferation assays, we examined the effects of exogenously administered and endogenously modulated levels of IGFBP-2 on the proliferation of DU145 cells. RESULT: Cell growth was stimulated by exogenously administered IGFBP-2, but significantly retarded (P < 0.05) by its neutralizing antibody. Overexpression of IGFBP-2 by transfection also stimulated cell growth, which was significantly (P < 0.05) inhibited in transfectants expressing antisense mRNA to IGFBP-2. Furthermore, the proliferation of IGFBP-2 overexpressing cells was significantly dampened by exogenously administered IGFBP-2 antibody. CONCLUSIONS: IGFBP-2 is an autocrine growth factor for DU145 human prostate cancer cells and cell proliferation can be significantly retarded by neutralizing or inhibiting its synthesis. These findings provide a strong rationale for targeting IGFBP-2 in the testing of novel strategies to treat prostate cancer. 相似文献
33.
以新鲜无壳牡蛎为原料,采用酶水解的方法制备牡蛎短肽,经SephadexG 15分离,并用HPLC测定其相对分子质量分布,通过HPLC法定量马尿酸测定各组分的ACE(血管紧张素转化酶)抑制活性。结果表明,牡蛎水解液中相对分子质量较大和较小部分的ACE抑制活性偏低,只有相对分子质量在一定范围内的短肽,对ACE具有较好的抑制作用,质量浓度为0.4mg/mL的牡蛎功能短肽的ACE抑制率为51.4%. 相似文献
34.
本文采用小鼠精子试验和小鼠睾丸DNA合成抑制试验,检测了JX-1对雄性生殖细胞的致突变作用。实验结果表明JX-1对小鼠精子总数、精子活动率及精子畸形率均无统计学意义的增加,与小鼠睾丸DNA合成抑制试验阴性反应一致。作者认为JX-1对雄性生殖细胞为一种非诱变剂。 相似文献
35.
David K.H. Lee 《Drug development research》1986,9(4):305-311
The effect of acute and subchronic dosing with etodolac on the renal PGE2 and 6-keto-PGF1α concentrations in the normal rat were studied. Etodolac and other nonsteroidal antiinflammatory drugs (NSAIDs) were administered orally, at equieffective antiinflammatory doses, to normal rats either as a single dose or as seven daily doses. Whole kidney prostaglandin (PG) concentrations were measured. In the acute study, etodolac (3 mg/kg) did not significantly lower the PGE2 levels for up to 4 hr postdosing. In contrast, naproxen (3 mg/kg) and piroxicam (0.5 mg/kg) significantly decreased the PGE2 levels to about 20% and 60% of control, respectively. Similar reductions in 6-keto-PGF1α concentrations were observed. In the subchronic study, etodolac (3 mg/kg/day) did not lower either PGF2 or 6-keto-PGF1α concentrations whereas naproxen (3 mg/kg/day), piroxicam (0.5 mg/kg/day), indomethacin (1 mg/kg/day), and aspirin (300 mg/kg/day) significantlydecreased both PGs. In both studies, the effect of etodolac was significantly different from that of the NSAIDs. It is concluded that etodolac possesses only a very weak capacity to lower renal PGs, and therefore is unlikely to cause any renal complications related to PG biosynthesis inhibition. 相似文献
36.
Teresa W. Tam Rui Liu John T. Arnason Anthony Krantis William A. Staines Pierre S. Haddad Brian C. Foster 《Journal of ethnopharmacology》2009,126(1):119-126
Aim of the study
Cree traditional medicine is commonly used concomitantly with prescribed drugs to treat health problems related to type II diabetes (T2D) that is endemic in the Cree population. However, the safety of traditional Cree medicines with respect to drug metabolism is unknown.Materials and methods
Seventeen anti-diabetic plant extracts were screened for their potential inhibition of 11 isoforms of the drug-metabolizing cytochrome P450s (CYPs), and flavin-containing monooxygenase 3 (FMO3) in fluorometric plate reader assays. Comparative analyses were conducted to determine if particular extracts were more inhibitory, or if particular enzymes were more inhibited.Results
Many anti-diabetic plant extracts inhibited the CYPs, with CYP2C and 3A isoforms being most prone to inhibition. The order of inhibition for the enzymes by the Cree plant extracts was: 2C19 > 3A7 > 3A5 > 3A4 > 2C9 > 2C8 > FMO3 > 1A2 > 2E1 > 19 > 2D6 > 2B6. Extracts from Rhododendron groenlandicum, Sorbus decora, and Kalmia angustifolia were identified as having strong inhibition towards many CYP isoforms.Conclusion
These findings demonstrate that extracts from most plant species examined have the potential to affect CYP2C- and 3A4-mediated metabolism, and have the potential to affect the bioavailability and pharmacokinetics of conventional and traditional medicines during concomitant use. 相似文献37.
目的评价中西医结合治疗激素敏感型系膜增生性肾炎的疗效。方法将122例呈肾病综合征表现并对强的松治疗敏感的非lgA系膜增生性肾炎患者随机分为两组,对照组按常规方法使用并撤减强的松,观察组在强的松常规治疗的基础上加用中药治疗。通过观察系膜增生性肾炎的复发及强的松副作用的发生情况评价中西医结合治疗系膜增生性肾炎的疗效。结果观察组系膜增生性肾炎的复发率及强的松副作用的发生率显著低于对照组(P<0.01)。结论中西医结合治疗激素敏感型系膜增生性肾炎,可以明显减少复发率及强的松的副作用。 相似文献
38.
采用无血清培养体系 ,研究肿瘤细胞自分泌调控机制。将人肝癌细胞培养在无血清无外源分裂因子培养基中 ,采用细胞原位计数法和免疫组织化学染色法 ,观察不同时相人肝癌细胞增生率的变化以及碱性成纤维细胞生长因子 (bFGF)的表达情况。结果 :人肝癌细胞生长良好 ,其增生速度与其分泌的bFGF量成正比。提示 :肝癌细胞在无外源生长因子的条件下通过分泌bFGF ,以自分泌和旁分泌的方式作用于自身和相邻细胞 ,促进细胞生长和增生。 相似文献
39.
R. K. Vesalainen K. U. O. Tahvanainen T. J. Kaila I. M. Kantola T. A. Kuusela D. L. Eckberg 《Clinical physiology and functional imaging》1997,17(2):135-133
We studied how posture influences the effects of transdermal scopolamine on autonomic cardiovascular regulation in a randomized, double-blind, placebo-controlled crossover study of 10 healthy young volunteers. We recorded the electrocardiogram and auscultatory sphygmomanometric and continuous non-invasive finger arterial pressure (Finapres device) to obtain signals for the beat-by-beat R–R interval and systolic, mean and diastolic pressures. R–R interval and arterial pressure variabilities were characterized by power spectral analysis. Scopolamine increased the mean R–R intervals and reduced arterial pressure in both the supine and the standing positions, but did not affect blood pressure variability. Scopolamine increased the total variability of R–R interval and its mid- (0·07–0·15 Hz) and high- (0·15–0·40 Hz) frequency band power in the standing position during controlled breathing at 0·25 Hz. In the supine position, scopolamine did not affect R–R interval variability. In the deep breathing test, scopolamine increased the maximal expiratory–inspiratory R–R interval ratio. This study showed that low-dose scopolamine increases vagal cardiac inhibition in both supine and standing positions in healthy volunteers. However, scopolamine increases heart rate variability only in the standing position during partial vagal withdrawal. The study also demonstrates that transdermal scopolamine decreases blood pressure in healthy young subjects. 相似文献
40.
We attempted to find out the role of α2-adrenoceptors of the medullary lateral reticular nucleus (LRN) in antinociception in rats. Spinal antinociception was evaluated using the tail-flick test, and supraspinal antinociception using the hotplate test. Antinociceptive effects were determined following local electric stimulation of the LRN, and following microinjections of medetomidine (an α2-adrenoceptor agonist; 1–10 μg), atipamezole (an α2-adrenoceptor antagonist; 20 μg) or lidocaine (4%) into the LRN. The experiments were performed using intact and spinalized Hannover-Wistar rats with a unilateral chronic guide cannula. Electric stimulation of the LRN as well as of the periaqueductal gray produced a significant spinal antinociceptive effect in intact rats. Medetomidine (1–10 μg), when microinjected into the LRN, produced no significant antinociceptive effect in the tail-flick test in intact rats. However, following spinalization, medetomidine in the LRN (10 μg) produced a significant atipamezole-reversible antinociceptive effect in the tail-flick test in the hot-plate test, medetomidine (10 μg) in the LRN produced a significant atipamezole-reversible increase of the paw-lick latency in intact rats. Microinjection of atipamezole (20 μg) or lidocaine alone into the LRN produced no significant effects in the tail-flick test. The results are in line with the previous evidence indicating brat the LRN and the adjacent ventrolateral medulla is involved in descending inhibition of spinal nocifensive responses. However, α2-adrenoceptors in the LRN do not mediate spinal antinociception but, on the contrary, their activation counteracts antinociception at the spinal cord level. The spinal aninociceptive effect of supraspinally administered medetomidine in spinalized rats can be explained by a spread of the drug (e.g., via circulation) which then directly activates α2-adrenoceptors at the spinal cord level. 相似文献