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101.
Two cases of adenomatoid odontogenic tumor were examined by light and electron microscopy. Morphologically the tumors could be divided into four layers. The ultrastructure of the tumor cells of each layer was revealed to be similar respectively to that of four layers seen in the enamel organ of a normal tooth germ. Duct-like structures and eosinophilic small areas were frequently present in compactly proliferating cell layers. Short columnar cells forming duct-like structures and eosinophilic small areas appeared similar ultrastructurally to ameloblasts during predentin formation. Therefore it seems reasonable to assume that this tumor originates from the enamel organ. The contents in the lumen of each eosinophilic small area varied, and seemed to be secreted into the stroma by circumscribing epithelial tumor cells. A fine filamentous layer was present in both of the duct-like structures and some of the eosinophilic small areas, and the former was different from the latter with respect to the alcian blue (pH 2.5) and toluidine blue (pH 4.4) staining reactions.  相似文献   
102.
We report two patients having recurrent breast cancer with brain metastases that was controlled well with a gamma knife radio-surgery. The patient is a 50-year-old woman. She underwent radical mastectomy for right breast cancer in September 1993. She suffered from multiple liver metastases in June 2000, so CEF therapy contained hepatic arterial infusion chemotherapy, and extended right lobectomy of the liver were performed in December 2001. Afterward, pleurodesis was carried out to the carcinomatous pleurisy. Then she underwent simple total hysterectomy and bilateral oophorectomy for torsion of the metastatic ovarian tumor. MRI study revealed brain metastases with a diameter of 1 cm in her right midbrain in April 2005, so a gamma knife radio-surgery was performed. After the radio-surgery, a weekly paclitaxel therapy followed by peroral chemotherapy with capecitabine was started, and she took the regimen continuously. Another patient is a 56-year-old woman. She underwent skin sparing mastectomy with axillary lymph node dissection for right breast cancer in November 2002. Metastases to the base of her skull were found in October 2004, so a gamma knife radio-surgery was carried out. After the radio-surgery, a weekly paclitaxel therapy with anastrozole was started. In both of the two patients, the metastatic brain tumors have not shown growth so far and are under good control as of March 2006.  相似文献   
103.
Real-time quantitative PCR, Western blot and in situ hybridization techniques were employed to clarify the presence of serine racemase in the primary cultures of rat neurons. We have detected both serine racemase mRNA and protein in the cultured neurons. Both the mRNA and the protein levels in the neurons are higher than those in the astrocytes. Sequential detection of serine racemase mRNA and MAP2 immunoreactivity also revealed that serine racemase and MAP2 are co-localized in the cultured neurons. These data are the first to demonstrate that a substantial amount of serine racemase exists in the cultured neurons.  相似文献   
104.
Kigamicin D is a novel anticancer agent that was identified using a new screening strategy that targets the tolerance of cancer cells to nutrient starvation [1, 2]. Oral administration of kigamicin D was previously described to show a strong antitumor effect in human tumor xenograft models of pancreatic tumors [2]. In this paper we describe that kigamicin D shows the same selective cytotoxicity against normal human cells such as lung fibroblast and prostate stromal cells under nutrient starved condition as against cancer cells. Kigamicin D inhibited tumor cell-induced angiogenesis in a dorsal air sac assay. On the basis of these results we tested other human tumor xenograft models and transplantable syngeneic tumor models in order to determine the spectrum of activity of kigamicin D against various cancers. Kigamicin D showed a weak antitumor effect against LX-1 and DMS-273 lung cancers, but had no effect on DLD-1 colon cancers. When tested against syngeneic tumors, kigamicin D showed a weak antitumor effect against colon26, but showed augmentation of tumor growth on IMC carcinoma at a broad dosage level. Kigamicin D does not show good antitumor activity against human xenograft tumors except pancreatic tumors and murine syngeneic tumors. We found that kigamicin D has excellent antitumor effect specific to pancreatic cancers. Surprisingly, high dosage of kigamicin D increased tumor growth of IMC carcinoma by than 200%. The phenomenon suggests that kigamicin D may cause some immunological response to the tumor.  相似文献   
105.
Otsuka Long-Evans Tokushima Fatty (OLETF) rats lack cholecystokinin-A receptor (CCK-AR) because of a genetic abnormality. We observed that body temperature homeostasis in response to changes in ambient temperature was deteriorated in OLETF rats, while the functions of the signal outputs from the hypothalamus to effectors were not impaired. Deteriorated homeostasis was also seen in CCK-AR deficient (-/-) mice. In the present study, we examined whether the sensory pathway involved in transmitting signals about temperature from the skin to the brain was impaired in OLETF rats. To elucidate the involvement of CCK-AR function, we conducted the same experiment in CCK-AR(-/-) mice. Responses to thermal pain were assessed using the Hargreaves' plantar test apparatus. Shortening of withdrawal latency was observed in OLETF rats compared to control rats, indicating thermal hyperalgesia. Behavioral responses following paw withdrawal were disturbed in OLETF rats. The 5-hydroxytryptamine (5-HT) and 5-hydroxyindole acetic acid contents in the hippocampus and frontal cortex of OLETF rats were significantly higher than in those of the controls. CCK-AR(-/-) mice did not show any differences from wild-type mice. In conclusion, OLETF rats showed thermal hyperalgesia and disturbed responses to thermal pain, and an alteration of 5-HT function might have a role in this disturbance.  相似文献   
106.
107.
OBJECTIVE: To ascertain predictors for the onset of different levels of certification of long-term care insurance among older adults living independently in a community. METHODS: Out of all residents aged 65 years and over living in Yoita town, Niigata prefecture, Japan (n = 1,673), 1,544 persons participated in the baseline interview survey in 2000 (response rate, 92.3%). Among these participants, 1,229 persons (79.6% of responders) were ranked as level 1, based on the hierarchical mobility level classification. They were followed up for the subsequent 3 years and 4 months to see whether they continued without certification of long-term care insurance or suffered onset of a "mild level", certified as levels "needing support" and 1 for long-term care insurance, or a "severe level" as 2-5. The Cox proportional hazards model with a stepwise method was used to identify the most parsimonious combination of predictors for each type of long-term care insurance certification. RESULTS: Of those who were followed up, 1,151 persons showed no disability in basic activities of daily living (ADL) at baseline nor died before application for long-term care during the follow-up and thus served for analysis. 1,055 persons (91.7%) remained as "no event", but 49 (4.3%) and 47 persons (4.1%) had onset of the "mild level" and the "severe level" during the follow-up, respectively. The final model for prediction of the "mild level" in both genders included advanced age and poor walking ability (hazard ratio (HR) for either unable or with difficulty: 7.22[95% CI, 1.56-33.52] in males and both unable and with difficulty: 3.28[95% CI, 1.28-8.42] in females). The final model for prediction of the "severe level" in both genders included advanced age and poor instrumental ADL (HR for < or = 4 marks: 3.74[95% CI, 1.59-8.76] in males and 3.90[95% CI, 1.32-11.54] in females). Severe cognitive decline was a predictor only for the "severe level" in males. A history of hospitalization during past 1 year and poor chewing ability were predictive only for the "mild level" in females. CONCLUSIONS: Among older adults living independently in a community, most predictors for subsequent onset of mild level-certification of long-term care insurance, except for advanced age, may be controlled by preventive strategies. Evaluating effectiveness of programs for this purpose warrants further study.  相似文献   
108.
Seven new neo-clerodane diterpenes, salvidivins A (2), B, (3), C (4), and D (5), salvinorins H (6) and I (7), and divinatorin [corrected] F (8), along with eight known neo-clerodane diterpenes, salvinorins A (1)-F, divinatorins A and B, and seven other constituents, were isolated from the hallucinogenic sage Salvia divinorum. The structures of 1-7 were elucidated on the basis of 2D NMR spectroscopic studies.  相似文献   
109.
A static x-ray fluorescent technique utilizing an 241Am source of low activity and a wide view diverging collimator which allows in vivo determination of the concentration and total content of iodine in the thyroid is described. Determinations of normal thyroidal iodine concentration and total iodine content were as follows: 0.40 mg/g and 10.6 mg for 16 men, and 0.67 mg/g and 17.6 mg for 14 women. This fluorescent system has been applied to 70 patients to date. Thyroidal iodine concentrations in patients with Graves' disease were approximately equal to those in healthy suspects, and little change was observed among the concentrations in patients before, during, or after treatment. In most of the patients with chronic or subacute thyroiditis, concentrations levels were lower.  相似文献   
110.
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