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61.
PURPOSE: The purpose of this study is to determine the optimum period and kind of exercise which are more effective for increasing the calcaneus osteo sono assessment index (OSI) in adolescent women. METHODS: The subjects consisted of 600 female students aged from 19 to 21 studying at the Department of Food and Nutrition at Nakamura Gakuen University. The calcaneus OSI was measured by ultrasonic bone absorptiometry. The factors associated with an increased OSI were determined using piecewise linear regression analyses. RESULTS: Experience in performing impact-loading exercise either in junior high school or high school was found to be a significant predictive factor for increased calcaneus OSI after adjusting for age and weight. Regarding other exercise-related factors such as subjective intensity, frequency, hours at a time, and total duration of exercise, a piecewise liner regression analysis showed that a total duration of over 7 yr and a high subjective intensity of the impact-loading exercise during high school and junior high school periods caused a significant increase in the calcaneus OSI. However, the OSI decreased when the subjective intensity of the impact-loading exercise during the high school period was reported to be "very strenuous." CONCLUSIONS: Impact-loading exercise in junior high school and high school is important for increasing calcaneus OSI; however, impact-loading exercise in high school with a "very strenuous" subjective intensity was also found to possibly decrease the calcaneus OSI.  相似文献   
62.
We present two cases of hepatic angiomyolipoma in which the size and internal composition of the tumor changed during the course of follow-up study. The tissue elements composing the tumor are thought to grow or regress independently during the disease's clinical course. Radiologists should be aware that hepatic angiomyolipoma can change in size and internal composition during its natural course.  相似文献   
63.
We attempted to determine whether cytoplasmic fat in clear cell renal cell carcinoma (RCC) can be identified by chemical shift gradient-echo magnetic resonance imaging (CSI). CSI was performed for 22 clear cell RCCs and 30 other renal tumors (including 16 non-clear cell RCCs), all of which were surgically proven. Signal reduction in out-of-phase images of these tumors was retrospectively evaluated and compared. The signal loss ratio (SLR) was defined and calculated. Fat staining of specimens from 16 tumors was performed and correlated with SLR. SLR was significantly higher in clear cell RCCs than in non-clear cell RCCs (P < 0.001). There was a significant correlation between degree of fat staining positivity of the specimens and SLR (P < 0.01). When signal reduction in out-of-phase images suggested the diagnosis of clear cell RCC, correct diagnosis of this entity was made in resected renal tumors with sensitivity, specificity, and accuracy of 82%, 90%, and 87%, respectively. CSI can demonstrate cytoplasmic fat in clear cell RCCs, which helps to differentiate this entity from other RCCs.  相似文献   
64.
We report a case of a huge retroperitoneal tumor in a 67-year-old woman. When the patient was taken to another hospital by ambulance, she had lost consciousness because of hypertension and hypoglycemia and abdominal CT revealed a huge retroperitoneal tumor with deviation of the right kidney and inferior vena cava. After further examinations including ultrasonography, MRI and angiography in our hospital, the tumor was extirpated. The tumor, 22 x 17 x 10 cm in size and 2,580 g in weight was diagnosed as hemangiopericytoma histologically. She has remained well with no evidence of recurrence for 9 months since the operation.  相似文献   
65.
To clarify noradrenergic systems on food intake of the neonatal chicks, we examined the effects of i.c.v injection of clonidine (CLON), an alpha2-receptor agonist, and fusaric (5-butylpicolinic) acid (FA), a dopamine (DA)-beta-hydroxylase (DBH) inhibitor. Although a high dose (250 ng) of CLON induced a narcoleptic response and reduced food intake, food intake at 30 min post-injection was enhanced by lower doses (25 and 50 ng) of CLON. Central administration of FA (25, 50 and 100 microg) increased food intake in a dose-dependent fashion. It is suggested that feeding behavior is stimulated by low levels of CLON and decreased by further production of norepinephrine (NE), and FA may play the disturbance of sleeping and then enhance food intake.  相似文献   
66.
67.
(E)-2-deoxy-2-(fluoromethylene)cytidine (FMdC), one of the most potent inhibitors of ribonucleoside diphosphate reductase, was selected for clinical development because of its novel mechanisms of action, and strong antitumor activity against experimental tumor models. This study was designed to determine the toxicities, maximum-tolerated dose (MTD), and pharmacokinetic profile of FMdC. FMdC was given orally for 5 consecutive days every 3 or 4 weeks in patients with advanced solid tumors. The starting dose was 8 mg/m2/day. Pharmacokinetic studies were carried out on days 1 through 5 of the first cycle. Ten patients with non-small cell lung cancer received 15 courses of FMdC at doses which were de-escalated from 8 mg/m2/day to 2 mg/m2/day because of unexpected severe toxicities at the starting dose level. Neutropenia was the dose-limiting toxicity. Thrombocytopenia and anemia were mild. Flu-like symptoms and fever were the common non-hematologic toxicities. The MTD was 4 mg/m2/day, since four of six patients developed grade 3–4 neutropenia. At the 4 mg/m2/day dose level, the mean terminal half-life, maximum plasma concentration (Cmax), plasma clearance, and mean residence time on day 1 were 3.20 h, 15.8 ng/ml, 2.91 l/h/kg, and 4.03 h, respectively. The recommended dose for phase II studies with this schedule is also 4 mg/m2/day for 5 days. Further investigations are necessary to establish optimal dosing schedules and routes for the administration of FMdC.  相似文献   
68.
Breast conserving surgery and radiation therapy (RT) can achieve a more favorable cosmetic outcome than mastectomy in patients with early breast cancer. However, it is widely recognized that RT is an impediment to improving the cosmetic outcome. Between 1985 and 1993, 113 patients were enrolled in a prospective randomized study to examine whether or not RT could be avoided following sector resection in patients with Stage I and II (UICC) invasive breast cancer. There was no significant difference in the 8 year local recurrence free survival rate between the RT and non-RT groups (92.3% versus 89.8% respectively). The characteristics of suitable patients would be negative nodes and microscopically negative resection margins. In conclusion, sector resection without RT is a reasonable option for some patients with early breast cancer.  相似文献   
69.
In male mice of ddY strain, a single dose of 1,1-dichloroethylene (1,1-DCE, 0.1 ml/kg, ip) produced severe renal damage at 24 hr, as evidenced by elevations in plasma urea nitrogen concentration and kidney calcium content and by massive renal tubular necrosis, while hepatic damage was less severe. A precipitous decrease in body temperature started as early as 30 min after administration of 1,1-DCE and lasted for 24 hr. Glutathione concentrations decreased in the liver and kidney, with a rebound increase seen in the former but not in the latter tissue. In carbon tetrachloride-poisoned mice, the renal toxicity of 1,1-DCE was markedly potentiated. Pretreatment with either diethyldithiocarbamate (DTC) or carbon disulfide (CS2) blocked all of these 1,1-DCE-induced toxic manifestations in normal and carbon tetrachloride-poisoned mice. Both agents, however, did not prevent the hypothermia induced by monochloroacetic acid or chloroacetyl chloride, proposed active metabolites of 1,1-DCE. Since DTC and CS2 inhibited hepatic and renal microsomal drug metabolizing enzyme activities (Masuda and Nakayama, 1982, Masuda and Nakayama, 1983), it is probable that the protective action of DTC and CS2 against renal and hepatic injury induced by 1,1-DCE may be due to an inhibition of the metabolic activation of 1,1-DCE to its proposed epoxide in each organ. The action of DTC given po may be mediated by CS2 produced in the stomach. The hypothermia induced by 1,1-DCE may not result from a direct action of 1,1-DCE per se, but by its metabolites.  相似文献   
70.
We developed a serum-free coculture model of benign prostatic hyperplasia (BPH) to clarify whether stromal cells stimulate growth of epithelial cells from BPH tissues. Epithelial and stromal cells from freshly isolated BPH tissue were cultured separately in defined serum-free WAJC 404/RPMI 1640 medium supplemented with insulin, transferrin, selenium, hydrocortisone, bovine serum albumin, epidermal growth factor, basic fibroblast growth factor and keratinocyte growth factor. (3)H-Tdr incorporation into epithelial cells and stromal cells was used as a measure of proliferation. When epithelial cells were cocultured with stromal cells, (3)H-Tdr incorporation into epithelial cells was increased in comparison to that in epithelial cells cultured alone. Dihydrotestosterone significantly increased this effect. It is likely that the in vitro coculture model reported here will be useful for isolating and understanding stromal cell-derived paracrine growth factor(s).  相似文献   
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