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61.
The aim of this study was to evaluate breast parenchymal activity on scintimammography with bone-seeking agents and 99mTc-MIBI. Scintimammography was performed with bone-seeking agents in 61 patients and with 99mTc-MIBI in 33 patients. Activity in the breast parenchyma contralateral to the suspected lesion was visually assessed by two independent observers. Increased breast parenchymal activity was shown in 19 of 61 patients examined with bone-seeking agents, while it was demonstrated in only two of 33 patients examined with 99mTc-MIBI. Breast parenchymal activity of bone-seeking agents was higher in patients aged 50 years or younger than in those older than 50. Increased parenchymal activity of bone-seeking agents may disturb visualization of primary breast cancer especially in relatively young patients. Low parenchymal activity is suggested to be a favorable characteristic of 99mTc-MIBI as a scintimammographic agent.  相似文献   
62.
Colonic absorption and distribution of lycopene, which inhibited rat colon carcinogenesis in our previous studies, were investigated in Sprague-Dawley rats. Three groups of six rats each with or without a single-barreled colostomy at the mid colon were given a single intragastric or intracolonic dose of 0.2 mL of corn oil containing 12 mg of lycopene. Twenty-four hours later, all rats were sacrificed and the blood and some tissues were collected. The contents of lycopene in the samples were assayed by HPLC. Lycopene was detected in an appreciable amount in the liver, but only in trace amount in the serum of all rats treated with an intracolonic dose of lycopene and in rats with an intragastric dose. After an intragastric lycopene treatment, lycopene was detected in the mucosa of the proximal colon and of the distal colon of the colostomized rats, whose distal colon had been excluded from the fecal stream. A large amount of lycopene was recovered in the feces. None was detected in any sample from the control rats treated with an intragastric or intracolonic dose of plain corn oil. The results suggest that lycopene is absorbed from the colon and also from the small intestine. It might be concluded that both ways of absorption contribute to a comparative amount of lycopene accumulation in the colon mucosa after ingestion of this carotenoid.  相似文献   
63.
64.

Purpose

It is well established that hyperprolactinemia, most typically seen in prolactinoma patients, causes hypogonadism and impotence. There seem to be a good possibility that hyperprolactinemia causes impotence, at least partially via some intrinsic property of prolactin (PRL), rather than through its suppressive effects on the hypothalamic-pituitary-gonadal testosterone dynamics. In the present investigation, we used an in vitro canine model to attempt to clarify whether direct action of PRL on the corpus cavernosum penis may lead to erectile insufficiency. Growth hormone (GH) and placental lactogen (PL), both having close structural and functional homologies to PRL, were also studied.

Materials and Methods

Isometric tension measurement with cavernous strips was performed in the presence or absence of 10 sup -5 to 10 sup -9 M. PRL, GH, or PL in the perfusion medium. The tension change induced by the test substances was normalized relative to that induced by 120 mEq KCl.

Results

Both PRL and GH produced dose-related elevations (p less than 0.01) of the cavernous tension, whereas PL and thiol-cleaved PRL in comparable doses were without effect (p greater than 0.05). When the tension rise produced by 120 mEq KCl was taken as 100 percent, the maximum contractions produced by PRL and GH were 80 percent and 110 percent. The minimum effective concentration was 10 sup -8 to 10 sup -7 M. for both PRL and GH. Pretreatment with indomethacin (10 sup -5 M.), but not tetrodotoxin (10 sup -5 M.), partially suppressed (p less than 0.05) the effects of PRL.

Conclusion

These results suggest that PRL and GH directly and specifically produced contraction of the corpus cavernosum penis, resulting in erectile insufficiency, and that the effect of PRL is partially mediated by prostaglandin.  相似文献   
65.
It has been reported that a number of toxic agents impair normal vitamin A (VA) metabolism (A. D. Bruin, 1976, In Biochemical Toxicology of Environmental Agents, pp. 937–980. Elsevier, Amsterdam). A study was conducted to explore the effect of cadmium chloride (CdCl2) on VA metabolism. Female rats of the Wistar strain were given drinking water containing 50 ppm of cadmium (Cd) for 237 days. Cadmium ingestion did not affect the food intake and body weight, but a significant decrease in serum VA was observed, concurrently with an increase in liver VA. In studying ingestion of tritiated VA alcohol (all trans-[15-3H]retinol), it was found that the absorption of VA alcohol from the intestine, the release of newly absorbed VA from the liver to serum, and the conversion of VA to water-soluble metabolites in the liver were not influenced by Cd. These findings suggest that Cd interfered with the release of VA, especially stored VA, to serum.  相似文献   
66.
Bagchi A  Oshima Y  Hikino H 《Planta medica》1991,57(3):282-283
From the roots and rhizomes of NARDOSTACHYS JATAMANSI, two new eudesmanes jatamols A and B were isolated, and their structures were determined by spectral analysis and chemical evidence.  相似文献   
67.
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69.
The mechanism of macrolide therapy in chronic sinusitis patients is unclear. The authors studied the effect of macrolides on interleukin (IL)-8 secretion from cultured human nasal epithelial cells. Epithelial cells harvested from the nasal polyps of patients with chronic sinusitis were primary-cultured, and secreted IL-8 in culture media was measured by enzyme immunoassay. The cells secreted considerable amounts of IL-8 constitutively and in response to lipopolysaccharide. The secretion was significantly inhibited by 10?5 M of erythromycin, clarithromycin, roxithromycin, and josamycin. 10?6 M erythromycin still showed the inhibitory effect, whereas the same concentration of josamycin did not. These results indicate that macrolide antibiotics may act as an immunomodulator to reduce IL-8 in inflammatory sites and, at least partially, account for the clinically discrepant effects between 14- and 16-membered ring macrolides in long-term low-dose therapy for chronic sinusitis.  相似文献   
70.
Although maladaptive coping strategies in eating disorder patients have been reported, the relationship between impulsivity and coping strategy has not previously been studied. Subjects consisted of 43 patients with anorexia nervosa restricting type (AN-R), 42 patients with anorexia nervosa binge eating/purging type (AN-BP), 71 patients with bulimia nervosa purging type (BN), and 97 controls. The Coping Inventory for Stressful Situations was used to evaluate coping strategies. Only AN-BP patients had a significantly lower task oriented-coping score than controls, and AN-R and BN patient groups used significantly less social diversion-avoidance coping strategies than controls. Emotion-oriented coping scores of AN-BP and BN patients were significantly higher than those of controls. In addition, impulsive BN patients had significantly higher emotional coping scores than less impulsive BN patients. These results suggest that maladaptive coping strategies may be a perpetuating factor even for impulsive patients and emphasizing a change in maladaptive coping strategies may be a useful treatment strategy even for highly impulsive patients.  相似文献   
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