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Y Kamimura

Publications and source records attributed to Y Kamimura.

At least 37 records · Page 2Linked to original sources
PubMed1994

Venous malformation in the posterior fossa: guidelines for treatment.

Venous malformations in the posterior fossa are relatively rare. Although the introduction of CT and MRI has made them easier to detect, their treatment is still controversial. Based on our experience with six patients and a review of the literature, we have tried to establish guidelines for their treatment. Since they have a benign natural course and may provide venous drainage in the posterior fossa, venous malformation found incidentally, unruptured venous malformation with nonhaemorrhagic complications, and those accompanied by small intracerebellar haematoma of less than 2 cm in diameter due to their rupture, should be treated conservatively unless they are associated with a coexistent malformation. Venous malformation with intracerebellar haematoma larger than 3 cm or reexpansion of the haematoma due to rebleeding should be treated surgically by evacuation of the haematoma. Resection of venous malformations in the posterior fossa should be restricted to cases in which the malformation is small and does not serve as a functional venous drainage route. Radiation therapy, including the "gamma-knife", may be a treatment of choice in the future.

Adult↗
PubMed1993

Endothelin-1 induces contraction of bile canaliculi in isolated rat hepatocytes.

To examine the effects of endothelin-1(ET-1) on bile canalicular contractions, rat hepatocytes were isolated by a collagenase perfusion technique and cultured on p-n-p-vinylbenzenyl-D-lactonamide-coated dishes under serum-free conditions. The frequency of bile canalicular contractions was expressed by the percentage of the number of bile canaliculi(BC) that contracted compared to the total number of BC observed for 10 min. The treatment of the hepatocytes with ET-1 increased the frequency of contraction of the BC in a dose-dependent manner up to 2nM, control: 10.4%; 0.5nM ET-1:31.6%; 1nM ET-1:54.0%; 2nM ET-1:58.0%; 4nM ET-1:58.9%. The contraction, once it occurred, lasted for rest of the observation period. We also observed a transient increase in the concentration of intracellular Ca in cultured hepatocytes upon the addition of ET-1 to the medium. These results suggest that ET-1 plays an important role in the mortility of BC in vivo.

Animals↗
PubMed1993

High sensitivity of LEC rats with chronic hepatitis to hepatocarcinogenesis: decreases in unscheduled and replicative DNA synthesis of the hepatocytes.

We carried out the following three experiments to clarify the mechanism of hepatocarcinogenesis in Long-Evans Cinnamon (LEC) rats. (1) Sensitivity to diethylnitrosamine (DEN): LEC rats (8 and 25 weeks old) without and with hepatitis and age-matched F344 rats were administered an intraperitoneal injection of a low dose of DEN. Eight weeks after the injection, the numbers of glutathione-S-transferase placental-form (GST-P)-positive foci in the 33-week-old LEC rat liver were significantly higher than those in the livers of the other three groups of rats. (2) Potential for unscheduled DNA synthesis (UDS): Isolated hepatocytes of 25-week-old LEC rats with chronic hepatitis showed about one-third the level of UDS induced by UV irradiation, as compared to that of age-matched F344 rats, while no significant difference was found between the UDS of isolated hepatocytes of 8-week-old LEC rats and age-matched F344 rats. (3) Potential for proliferation: Isolated hepatocytes from 8-week-old LEC rats responded well to epidermal growth factor (EGF) in culture, to almost the same degree as F344 rat hepatocytes, while a remarkable decrease in the responsiveness of hepatocytes isolated from 25-week-old LEC rats to EGF was found. These results suggested that LEC rat hepatocellular carcinoma could be naturally initiated after the onset of hepatitis by carcinogens contaminating food and the environment, probably due to the reduction of DNA repair activity, after which initiated hepatocytes selectively proliferate in response to growth stimuli endogenously produced as a result of continuous loss of hepatocytes (chronic hepatitis), because of a decrease in growth activity of non-initiated hepatocytes.

Animals↗
PubMed1993

[Predictive factors for in-hospital mortality and delayed mortality following aneurysmal subarachnoid hemorrhage].

It is important to detect predictive factors for in-hospital and delayed mortality of patients with subarachnoid hemorrhage (SAH) due to ruptured aneurysm. Forty-eight patients with initial bleeding of aneurysmal SAH were referred to our hospital from January 1982 to December 1985. In-hospital mortality was 16.7% (8 to 48), and 15% (6) of forty patients died later during the follow-up period. Using the Kaplan-Meier method we were able to conclude that, cumulatively, there was 70.8% probability that much patients would survive for 10 years. We analysed predictive factors of in-hospital and delayed mortality retrospectively. The most significant predictive factor for in-hospital mortality was SAH grading on admission, and for delayed mortality (29.2%) age on admission was the best predictive factor. In fact, two patients died with cardiac event during the follow-up period. This result suggests that, although the SAH grading on admission was the second most significant factor for delayed mortality, patients who survived in the acute phase had a survival probability similar to those in a normal control group.

Adult↗
PubMed1991

[Ossifying fibroma in the cranial vault. Case report].

Ossifying fibroma is relatively common in the maxilla, but rare in the cranial vault. A 10-year-old girl was referred for painful swelling of the left temporal region. On admission, she presented no abnormal physical and neurological findings except for the painful swelling. Plain skull X-ray films showed a radiolucent lesion of the left temporal bone about 4 cm in diameter, with a hyperostotic area of the parietal side. Computed tomography scan using bone window level also showed an abnormal density lesion in the same site. Curettage of this tumor was performed from a cosmetic point of view and at the family's petition. Histological examination showed vascular fibrous tissue in which lamellar bone was surrounded by osteoblasts.

Child↗
PubMed1989

[Gonadotropin, as a tumor marker, in body fluid and tumor tissues of germ cell tumors].

The value of gonadotropin in the body fluids of germ cell tumor patients is its usefulness as a tumor marker. It is also used for differential diagnosis and/or judgement of therapeutic effects. In order to clarify the most effective value of gonadotropin as a tumor marker in the body fluids, we compared the value in serum, liquor and urine with one another. The liquor contained highest (1650 IU/l) value of gonadotropin in the primary intracranial germ cell tumors, mostly in choriocarcinoma. But the gonadotropin value was highest (3050 IU/l) in the serum of secondary intracranial choriocarcinoma. Chiasmal germ cell tumor, except choriocarcinoma, which does frequently secrete gonadotropin (alpha, beta) showed moderate or very high values in the liquor. However, pineal germ cell tumors rarely secrete gonadotropin and sometimes mild high value are obtained in the serum without gonadotropin secretion immunohistochemically. In such cases, the gonadotropin may be increased by indirect mechanism of gonadotropin-secretion following pineal disorder. In most of such cases, the gonadotropin was not human chorionic gonadotropin (HCG) but lutein hormone (LH). Because alpha-subunit of such gonadotropin has the same structure, their antibodies show immunologic cross reaction. So, a count of beta-subunit gonadotropin in the serum or liquor is the best way for differential diagnosis or judgement of therapeutic effects. From our results, it is considered that the tumor secretes HCG if the serum beta-HCG value was higher than 30 IU/l, and that it doesn't secrete HCG if beta-HCG value was lower than 10 IU/l or non calculable. The mild increased HCG may be caused by hypothalamo-diencephalic disorder such as pineal tumor.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗
PubMed1989

[Dental radiographic survey of rapidly progressive periodontitis].

The purpose of this study was to determine the prevalence of rapidly progressive periodontitis (RPP) by radiographic evaluation in patient at the department of conservative dentistry, Ohu University hospital during two years from 1987 to 1988. The survey was conducted on 370 patients. The radiographic evaluation was done by the method of Schei. The results obtained were as follows. 1. The number of RPP patient was eight. The prevalence of RPP in all patients and periodontitis patients were 2.1%, 6.0%, respectively. RPP patients consisted of 4 females and 4 males. 2. The age of RPP patients ranged from 34 to 41 (mean age 37.5) years old. 3. The number of affected and missed teeth ranged from 4 to 19 (mean 12.1), 0 to 23 (mean 8.0), respectively in RPP patients. 4. Severe alveolar bone loss (more than 50%) was observed in the teeth except canine.

Adult↗
PubMed1989

[The influence of ferric metabolism on Ga-67 distribution in the human body].

This investigation was undertaken to make clear the influence of ferric metabolism on Ga-67 distribution in human body. Count ratios for each organ to femoral soft tissue (i.e. relative Ga-67 uptake) were calculated in 125 scintigrams obtained 48 hours following injection, and the relation between the relative Ga-67 uptake in each organ and serum Fe, or UIBC were investigated. The relative Ga-67 uptake in the liver and the lumbar vertebra had negative correlation to serum Fe, and had positive correlation to UIBC. However, there was no significant difference in the relative Ga-67 uptake in the lumbar vertebra between normal and high serum Fe group. Only in group with exceedingly low serum Fe, each vertebral body was visualized separately in posterior view of the abdomen. These findings indicated that in group with exceedingly low serum Fe, Ga-67 accumulated mainly in the bone marrow, and in group with high serum Fe, Ga-67 accumulated mainly in the bone. The urinary bladder was visualized only in group with high serum Fe, which suggested that the excretion of Ga-67 to the urine was continued yet at 48 hours after injection. Ferric metabolism affected remarkably on the relative Ga-67 uptake in the liver, the bone marrow and the bone, and also the excretion of Ga-67 to the urine.

Adolescent↗
PubMed1985

Post-traumatic epidural hematoma in two patients with long-standing "arrested" hydrocephalus.

The occurrence of a post-traumatic epidural hematoma in two patients with long-standing "arrested" hydrocephalus is reported. There was a relatively long interval between the head injury and the onset of symptoms. The large hematoma was accommodated by the decrease in size of the markedly dilated ventricles. This report stresses the possibility of the presence of an epidural hematoma in the management of head injury in patients with long-standing "arrested" hydrocephalus.

Adult↗