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排序方式: 共有400条查询结果,搜索用时 15 毫秒
391.
红花黄素对高血压大鼠的降压作用及对肾素-血管紧张素的影响 总被引:31,自引:0,他引:31
Safflower yellow (SY) is a mixture of chalconoid compounds extracted from Carthamus tinctorius L. Ig SY 1~2 g·kg-1·d-1lowered the blood pressure of spontaneously hypertensiverats (SHR), for about 1.86~3.86 kPa. Five weeks after administration of SY, the plasma renin ac-tivity and angiotensin Ⅱ level diminished in the SHR experimental groups. These suggest that the de-crease of blood pressure is mediated by the renin-angiotensin system. 相似文献
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394.
Otacilio D Benvindo Nilberto RF Nascimento Claudia F Santos Manasses C Fonteles Edilberto R Silveira Daniel E Uchoa Adriana R Campos Karina MA Cunha Flavia A Santos Vietla S Rao 《Asian journal of andrology》2011,13(5):747-753
Compounds with dual action on cyclic adenosine monophosphate (cAMP) and cyclic guanosine monophosphate (cGMP) may be a treatment option for erectile dysfunction, as they not only promote penile erection but also prevent the upregulation of phosphodiesterase-5. In this study, we examined the possible relaxant effect and mechanism of 17-nor-subincanadine E (SEC, 0.2–200 µmol l−1), a plant-derived alkaloid, in rabbit corpus cavernosum (RbCC) strips that had been precontracted by exposure to phenylephrine (10 µmol l−1) or a high concentration of K+ (60 mmol l−1) in vitro. In addition to SEC''s effect on cAMP and cGMP levels, electrical field stimulation (EFS) in phenylephrine-precontracted RbCC and calcium chloride (1–100 mmol l−1) evoked responses in depolarized RbCC were analysed. SEC relaxed the phenylephrine-precontracted RbCCs in a concentration-dependent manner. Atropine, guanethidine and N-ω-nitro-ℓ-arginine methyl ester (L-NAME) did not have any effect on the relaxation of RBCCs. When 1H-1, 2, 4oxadiazole[4,3-a] quinoxalin-1-one (ODQ) was added, it effectively blocked the relaxant response of SEC. Although SEC enhanced the maximal relaxation produced by sodium nitroprusside (SNP) and forskolin in phenylephrine-precontracted cavernosal smooth muscle, it caused a decrease in the maximal contractile response induced by calcium chloride in depolarized RbCCs. The relaxant effect of SEC was paralleled by an increase in the tissue levels of the cyclic nucleotides cAMP and cGMP. We conclude that SEC promotes the relaxation of RbCC, possibly favouring cAMP and cGMP accumulation and calcium blockade. This novel mechanism could be useful for patients who do not benefit from phosphodiesterase inhibitors and for those with endothelial and nitrergic dysfunction, such as patients with diabetes, hypertension and dyslipidaemias. 相似文献
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397.
Veld PA; Weber RF; Los FJ; den Hollander N; Dhont M; Pieters MH; Van Hemel JO 《Human reproduction (Oxford, England)》1997,12(8):1642-1644
Two case histories are presented documenting structural chromosome
abnormalities in infertile males. The abnormalities were detected only
after application of intracytoplasmic sperm injection (ICSI) was repeatedly
unsuccessful or resulted in an abnormal pregnancy. A mosaic Robertsonian
translocation 45,XY,der(13;13)(q10; q10)/46,XY,t(13;13)(p10;p10),
der(13p;13p) incompatible with normal offspring was found in a male with
extreme oligozoospermia after three subsequent ICSI treatments were
unsuccessful and one had resulted in a spontaneous abortion. A second case
involved a Robertsonian translocation 45,XY,der(13;14)(q10;q10) which was
detected in a male with extreme oligozoospermia after ultrasound
abnormalities were found in an ICSI-induced twin pregnancy. Amniocentesis
showed an unbalanced 46,XY,+13,der(13;14)(q10;q10) karyotype in one twin
and a Robertsonian 45,XX,der(13;14)(q10;q10) karyotype in the other twin.
Chromosome analysis of males with abnormal sperm characteristics is advised
prior to ICSI.
相似文献
398.
LAA Kollée M Cuttini D Delmas E Papiernik AL den Ouden R Agostino K Boerch G Bréart J-L Chabernaud ES Draper L Gortner W Künzel RF Maier J Mazela D Milligan P Van Reempts T Weber J Zeitlin the MOSAIC Research group 《BJOG : an international journal of obstetrics and gynaecology》2009,116(11):1481-1491
399.
Interleukin-1 (IL-1) treatment of human WI-38 lung fibroblasts results in granulocyte-macrophage colony-stimulating factor (GM-CSF) expression as well as a delayed increase in prostaglandin E2 (PGE2) production that closely correlates with the decline of GM-CSF mRNA levels. Pretreatment with PGE2 reduces the IL-1 induced GM-CSF mRNA and protein expression to 10% to 15% of control values at concentrations of PGE2 that are endogenously produced after IL-1 stimulation. Inhibition of PGE2 synthesis by indomethacin prolongs the IL-1 induced GM-CSF mRNA expression and increases the cumulative GM-CSF protein secretion. Exposure of WI-38 fibroblasts to PGE2 results in an increase in intracellular cyclic adenosine monophosphate (cAMP) levels. The inhibition of GM-CSF expression by PGE2 can be mimicked by stable cAMP analogs as well as cAMP elevating agents such as cholera toxin, forskolin, and isobutylmethylxanthine. Thus the inhibition exerted by PGE2 is mediated via cAMP. Taken together, these results suggest that IL-1 stimulation of human fibroblasts provides not only the upregulatory signal for GM-CSF expression but also a delayed and indirect downregulatory signal that serves to limit GM-CSF expression in the continued presence of IL-1. 相似文献
400.
Geller RB; Saral R; Piantadosi S; Zahurak M; Vogelsang GB; Wingard JR; Ambinder RF; Beschorner WB; Braine HG; Burns WH 《Blood》1989,73(8):2209-2218
Ninety-nine patients with acute nonlymphocytic leukemia (ANLL) received HLA-identical bone marrow transplants (BMTs) from sibling donors after preparation with high doses of busulfan and cyclophosphamide. Forty- nine patients were transplanted in first complete remission (CR), and 50 patients were transplanted in second and third CR and early relapse. Fifty-three received one of three regimens containing primarily low- dose cyclophosphamide (group I) for graft-v-host disease (GVHD) prophylaxis; since March 1983, 46 patients received intravenous (IV) cyclosporine (group II). After December 1983, only cytomegalovirus (CMV)-seronegative blood products were used in appropriate patients, and since April 1984 patients seropositive for herpes-simplex virus (HSV) and CMV received high-dose acyclovir prophylaxis. For patients transplanted in first CR, there was a significantly lower incidence of acute GVHD (P = .005) and deaths related to GVHD and interstitial pneumonitis (P = .001) in patients in group II. This was reflected in an improved Kaplan-Meier probability of disease-free survival (DFS) in the 22 patients transplanted in group II as compared with the 27 patients in group I (64% +/- 10% v 30% +/- 9%, P = .017). The probability of remaining in remission was slightly lower in group II (82% +/- 9% v 94% +/- 6%, P = .479). For patients transplanted in second and third CR and early relapse, the incidence of acute GVHD (P = .026) and deaths related to GVHD and interstitial pneumonitis was significantly lower in group II (P = .029); the probability of remaining in remission was also less (47% +/- 15% v 91% +/- 15%, P = .022). However, the probability of DFS was not significantly different between the two groups (26% +/- 10% v 35% +/- 18%, P = .957). We conclude that transplantation for patients in first CR who received IV cyclosporine therapy is effective treatment; patients with more refractory disease treated with the same cyclosporine regimen (group II) had a lower incidence of GVHD than those treated in group I, but survival did not improve because of an increase in the number of relapses and other nonleukemic complications. 相似文献