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本文观察了[D-Ala6,Pro9-Ethylamide10]-LHRH(LHRH-A)对孕中期大鼠的抗妊娠作用。结果显示:在孕9~11d sc 200μg/d LHRH-A,血浆孕酮水平自第二次给药后明显下降(P<0.05),给药大鼠均流产终止妊娠;LHRH-A的抗妊娠作用可被醋酸甲地孕酮所拮抗;LHRH-A对体外培养的假孕大鼠和孕d 9大鼠黄体细胞分泌孕酮有明显的直接抑制作用。 相似文献
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A. Tavakkolizadeh A.P. Ramsanahie L.L. Levitsky M.J. Zinner S.W. Ashley E.E. Whang D.B. Rhoads 《The Journal of surgical research》2004,121(2):273
The objective of this study was to examine the function of vagal innervation in maintaining diurnal rhythmicity in the expression of intestinal absorptive genes. Rats underwent truncal vagotomy and were maintained for 7 days on nighttime scheduled feeding (12-h light/12-h dark cycle). Vagotomized rats (V; n = 9) were pair-fed with sham-operated controls (S; n = 4). Unoperated normal rats (N; n = 6) were also included as controls. Half the rats were killed 3 h after lights on (ZT3; Zeitgeber Time, with lights-on considered ZT0) and the other half at ZT9, the time interval over which we have previously shown that sucrase and sugar transporter expression exhibits a significant anticipatory increase. RNA and protein extracted from mucosa of proximal jejunums were subjected to Northern and Western blot analyses to assess the increase in gene expression. Sham operation did not alter the normal diurnal rhythmicity of intestinal gene expression. Control rats (S plus N) exhibited the expected increase in RNA levels at ZT9 versus ZT3 for SGLT1 (4.5-fold), GLUT2 (5.3-fold), GLUT5 (4.1-fold), and sucrase (2.9-fold; P > 0.001 in all cases). In contrast, the induction in V rats was markedly blunted for GLUT2 (1.3-fold) and sucrase (1.5-fold) but not for SGLT1 (5.0-fold) or GLUT5 (4.2-fold). The mRNA levels for GLUT2 and sucrase at ZT9 were significantly lower in V rats versus controls (P < 0.001). GLUT2 and SGLT1 protein levels exhibited a parallel pattern: SGLT1 induction was 4.3-fold in control rats (P < 0.01) and 3.8-fold in V rats (P <0.01), whereas GLUT2 induction was 3.3-fold in control rats (P < 0.01) but only 1.4-fold in V rats (NS). Our results indicate that signaling through the vagus nerve is necessary to maintain the anticipatory induction pattern of GLUT2 and sucrase. The persistent rhythm in both SGLT1 and GLUT5 indicates that (1) diurnal induction of these genes is independent of vagal innervation and (2) the procedure did not cause an overall loss of intestinal function. Thus, entrainment of anticipatory diurnal gene expression in the intestine occurs via two separate pathways that are differentially dependent on vagal input. 相似文献
5.
A randomized controlled trial of electromagnetic therapy in the primary care management of venous leg ulceration 总被引:1,自引:1,他引:0
OBJECTIVE: The aim was to establish the potential efficacy, tolerabilityand side-effect profile of electromagnetic therapy as an adjunctto conventional dressings in the treatment of venous leg ulcers. METHOD: A prospective, randomized, double blind controlled clinicaltrial was carried out in a dedicated leg ulcer clinic basedin one urban general practice. Nineteen patients with leg ulcersof confirmed venous aetiology were assessed. The main outcomemeasures were rate and scale of venous leg ulcer healing, changesin patient-reported pain levels, quality of life, degree ofmobility, side effect profile and acceptability to patientsand staff. RESULTS: Sixty-eight per cent of patients attending this dedicated clinicachieved improvements in the size of their ulcer (4, 21%, healedfully) and in reduced pain levels (P < 0.05) during the trial,despite the chronicity of ulcer histories. Patients treatedwith electromagnetic therapy at 800 Hz were found at day 50to have significantly greater healing (P < 0.05) and paincontrol (P < 0.05) than placebo therapy or treatment with600 Hz. All patients reported improved mobility at the end ofthe study. The electromagnetic therapy was well tolerated bypatients, with no differences between groups in reporting adverseevents, and proved acceptable to staff. CONCLUSION: Despite the small numbers in this pilot study, electromagnetictherapy provided significant gains in the healing of venousleg ulcers and reduction in pain. Keywords. Electromagnetic therapy, RCT, leg ulcers, primary care. 相似文献
6.
Intestinal schistosomiasis japonica: CT-pathologic correlation 总被引:1,自引:0,他引:1
Lee RC; Chiang JH; Chou YH; Rubesin SE; Wu HP; Jeng WC; Hsu CC; Tiu CM; Chang T 《Radiology》1994,193(2):539
7.
Cisplatin is a common cause of hypomagnesemia and hypokalemia due to renal magnesium (Mg) and potassium (K) losses. Magnesium plays an important role in the maintenance of intracellular K. An unrecognized and untreated Mg depletion can lead to a refractory K repletion. We describe two patients with hypomagnesemia-associated refractory hypokalemia following cisplatin following cisplatin therapy. Potassium supplementation failed to replace the K deficit. Profound hypokalemia persisted until hypomagnesemia was recognized and corrected. In neither patient was the concurrent hypomagnesemia recognized until the 11th and 9th hospital days. These two cases demonstrated the association of a refractory K repletion and an Mg deficiency. Thus, both serum K ion and Mg levels should routinely be assessed in patients who require cisplatin therapy. 相似文献
8.
Iridium films having near-bulk properties were formed by electron-beam evaporation with simultaneous bombardment of Ar ion beam. The charge-injection capabilities of Ir film were investigated, and the detrusor pressure induced by S2 stimulation with Ir-coated Pt electrode was measured and compared with the uncoated Pt electrode. The charge densities of Ir film were continuously increased with increase in the number of cycles in 0.1 M H2SO4 due to the accumulation of the iridium oxide phase. The iridium oxide formed contained nano-pores, and oxides had different dielectric properties. The Ir film could inject various amounts of charge in physiological solution under the identical stimulating condition depending on the degree of activation in 0.1 M H2SO4. S2 stimulation by Ir-coated Pt electrode caused more efficient bladder contraction of the male dog than the uncoated Pt electrode under the identical stimulus condition. 相似文献
9.
Genetic mapping of the human homologue (T) of mouse T(Brachyury) and a search for allele association between human T and spina bifida 总被引:3,自引:0,他引:3
10.
Kim YH; de Kretser DM; Temple-Smith PD; Hearn MT; McFarlane JR 《Molecular human reproduction》1997,3(4):307-313
Using mechanical and chemical dissection methods, fibrous sheath was
isolated both from normal ejaculated human spermatozoa and from rabbit
cauda epididymal spermatozoa. The same techniques did not produce a pure
preparation of fibrous sheath from ejaculated rabbit spermatozoa,
suggesting that further cross-linking and stabilization of sperm structures
occurs in response to components of the seminal plasma. The isolation
procedures were monitored by phase contrast microscopy and the purity of
the fibrous sheath was verified by electron microscopy. Sodium dodecyl
sulphate-polyacrylamide gel electrophoresis (SDS-PAGE) of isolated human
fibrous sheath revealed at least 14 protein bands of which the most
intensely stained were of molecular weight 84, 72, 66.2, 57, 32 and 28.5
kDa. The rabbit fibrous sheath revealed at least 10 protein bands, of which
the most intensely stained were 35.2, 32.7 and 28.5 kDa. The amino acid
composition of the purified fibrous sheath from human and rabbit
spermatozoa was similar, being high in aspartic acid and/or asparagine and
glutamic acid and/or glutamine, serine, alanine, leucine, lysine and
glycine, but low in histidine, tyrosine and isoleucine. This composition is
similar to that reported for the rat and suggests that mammalian sperm tail
fibrous sheaths are composed of similar types of proteins, although there
are apparent differences in protein components between species.
相似文献