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排序方式: 共有2365条查询结果,搜索用时 15 毫秒
1.
A case of MELAS (mitochondrial encephalomyopathy, lactic acidosis, and stroke-like episodes) which presented as migraine
complicated by stroke is reported. Strokes associated with migraine have often been reported, but the mechanism remains unclear
and may include a variety of pathologies. MELAS also presents with migrainous headache, vomiting, and stroke-like symptoms.
Magnetic resonance imaging demonstrates characteristic findings. MELAS should be considered in the differential diagnosis
of infarct-like lesions with migrainous headaches in young adults, especially if the symptoms fluctuate and are accompanied
by a homonymous hemianopia.
Received: 23 September 1996 Accepted: 19 February 1997 相似文献
2.
M Kurihara S Shimauchi K Ohyama T Yamakawa H Watanabe S Hirakawa S Ohkuma 《Yakugaku zasshi : Journal of the Pharmaceutical Society of Japan》1990,110(10):783-787
One mol perchloric acid-soluble fraction (PASF) obtained from ascitic fluid of a patient (blood group B) with metastatic omentum tumor from ovarian cancer was a glycoprotein fraction containing 35.4% carbohydrate and exhibited A, B and Thomsen-Friedenreich (T) activities. This fraction was separated into three fractions, Frs. 1-3, by a gel filtration with Bio-Gel A-1.5 m column. Among these fractions, Fr. 1 which was obtained in a 5.5% yield to PASF, was a glycoprotein fraction with a high molecular weight, 23.3% carbohydrate and A, B and T activities. Other minor fraction, Fr. 2, and the major fraction, Fr. 3, contained 43.2% and 43.9% carbohydrate, but did not show A, B and T activities, respectively. 相似文献
3.
Eiichiro SUGIYAMA Takayoshi IKEDA Hiroshi MAEDA Takeshi MATSUO Masaru MATSUMOTO 《Congenital anomalies》1987,27(2):85-93
Abstract True incidence of this malformation is probably greater than that reported since the definitive diagnosis has been made at autopsy in most cases. Various hypotheses on the pathogenesis of tracheal agenesis have been proposed but they are still controversial.
In this report, we present a case of tracheal agenesis with a broncho-esophageal fistula and discuss the formal genesis. 相似文献
In this report, we present a case of tracheal agenesis with a broncho-esophageal fistula and discuss the formal genesis. 相似文献
4.
S Kobayashi M Tanaka K Masaki S Hirakawa K Momose 《Nippon Sanka Fujinka Gakkai zasshi》1992,44(2):223-228
Lipoprotein is known to increase during pregnancy but the factors responsible for the change have not been established. In addition, the lipoprotein concentration in preeclamptic pregnancy is significantly higher than in normal pregnancy. The apolipoproteins are an important determinant of metabolism and the structure of plasma lipoproteins. In normal pregnancies, non pregnancies and preeclamptic pregnancies the levels of blood apolipoproteins AI, AII, B and E were determined by TIA methods. (1) In normal pregnancies, the concentrations of apolipoproteins AI, AII, B and E were 182.6 +/- 20.9 mg/dl (n = 12, mean +/- S.D.), 33.3 +/- 5.7 mg/dl, 128.6 +/- 20.8 mg/dl, and 6.8 +/- 1.9 mg/dl, respectively. (2) In the pregnancies, the concentrations of apolipoproteins AI, AII, B and E were 135.6 +/- 9.3 mg/dl (n = 5), 30.8 +/- 1.9 mg/dl, 76.0 +/- 19.7 mg/dl, and 4.4 +/- 0.7 mg/dl, respectively. (3) In the preeclamptic pregnancy, the concentrations of apolipoproteins AI, AII, B and E were 181.0 +/- 27.6 mg/dl (n = 22), 33.2 +/- 4.8 mg/dl, 145.7 +/- 41.6 mg/dl and 5.8 +/- 1.4 mg/dl, respectively. The concentration of apolipoprotein B in preeclamptic pregnancy was significantly higher (p less than 0.001) and apolipoprotein E was significantly lower (p less than 0.01) than in normal pregnancies. These data suggest that the measurement of apolipoprotein is useful for the evaluation of preeclamptic pregnancy. 相似文献
5.
The effects of anesthesia on otoacoustic emissions 总被引:4,自引:0,他引:4
Noam Harel Akinobu Kakigi Haruo Hirakawa Richard J. Mount Robert V. Harrison 《Hearing research》1997,110(1-2):25-33
We have measured transient-evoked and distortion-product otoacoustic emissions (OAEs) in the chinchilla and compared them in the awake and anesthetized animal (using either ketamine or barbiturate agents). We report a significant increase in OAE amplitudes during anesthesia, particularly using ketamine. These effects are most evident for transient-evoked otoacoustic emissions (TEOAEs) as measured in the non-linear mode. Our data support the hypothesis that tonic activity levels in cochlear efferents may be reduced by anesthetic effects, either directly or indirectly (e.g., by general reductions in descending pathway activity), and that reduced cochlear efferent activity will result in the observed increase of OAE amplitudes. 相似文献
6.
7.
Shimizu S Yamada N Sawada T Ikeda K Nakatani K Seki S Kaneda K Hirakawa K 《Pathology international》2000,50(12):953-959
To demonstrate ultrastructural events in the early phase of hepatic metastasis of human colon carcinoma, we intrasplenically injected a highly metastasizable, human colon carcinoma cell line LM-H3 (1 x 10(6) cells) into nude mice, and electron microscopically investigated the hepatic metastasis. At 24 h, tumor cells adhered to the endothelial wall of terminal portal venules and periportal sinusoids. At 48-72 h, after extravasation, they deeply invaded the hepatic cell plate and the interstitial tissue of the portal tract, in which they underwent proliferation and made the metastatic foci. Tumor cells were linked with each other or with surrounding hepatocytes by desmosomes. Desmosomes were maintained during the mitosis. When invading tumor cells were exposed to the bile canaliculi, they generated microvilli on the surface. Microvilli were also formed at the luminal surface of intracytoplasmic inclusions. In the interstitial tissue of the portal tract, tumor cells were closely associated with fibroblasts. However, no junctional specializations were seen between them. The present study demonstrated that human colon carcinoma cell line LM-H3 formed desmosomes with hepatocytes soon after invasion of the hepatic cell plate, suggesting the regulatory role of an interaction with hepatocytes in the growth of metastatic foci within the liver parenchyma. 相似文献
8.
Yang M Moriya T Oguma M De La Cruz C Endoh M Ishida T Hirakawa H Orita Y Ohuchi N Sasano H 《Pathology international》2003,53(7):422-428
Microinvasive ductal carcinoma of the breast, namely ductal carcinoma in situ with microinvasion (T1mic) as defined by the American Joint Committee on Cancer (AJCC) Staging Manual, is a rare disease, although it is increasing because of widespread use of mammography. The aim of the present study was to describe the clinicopathological and immunohistochemical features of this entity. Twenty-eight patients who were diagnosed as T1mic from January 1997 to August 2002 were studied by using 3-5 mm-thick serial sections with hematoxylin-eosin staining. Immunohistochemical staining for the estrogen receptor (ER), progesterone receptor (PR), p53, Ki-67, and HER-2 were performed. All 28 patients were female, with a mean age of 48.8 years. Twenty-six patients (93%) revealed mammographic abnormalities on routine examination. All foci of the invasions were measured using an ocular micrometer. Invasive foci consisted of isolated cells or cell clusters, or appeared as a tongue-like projection of tumor through the basement membrane of the duct of ductal carcinoma in situ (DCIS). The mean number of invasive foci was 3, and the mean size was 0.6 mm. We found that high nuclear grade and predominant comedo subtype of DCIS components were 57.1% and 46.4%, respectively. Twenty-four cases (86%) demonstrated necrosis of DCIS components. Microinvasion was often associated with periductal stromal reaction (71.5%) and/or a lymphocytic infiltration (78.6%). All patients, excluding two, received axillary resection (the mean number of lymph nodes examined per case was 12), and none had lymph node metastasis. The positive expression of ER and PR strongly related to low grade nuclei and non-comedo subtype; however, the positive expression of HER-2 and P53 related to high grade nuclei and comedo subtype (P<0.01). Ki-67 expression was significantly higher in the high grade nuclei group than in the low grade group (P<0.01). Our study suggested that high nuclear grade and comedo DCIS were more aggressive and more common with microinvasion, and that microinvasion is more likely to be multifocal. 相似文献
9.
Kawauchi S Liu XP Kawasaki K Hirakawa T Amada S Furuya T Oga A Sasaki K 《The Journal of pathology》2004,204(3):268-276
To clarify the mechanisms underlying cell cycle promotion in malignant germ cell tumours of the ovary (MGCTOs), beta-catenin and components of the pRB pathway, cyclin D1 and p16, were analysed in relation to cell proliferation. Immunohistochemically, p16 protein was not expressed in a number of MGCTOs (9 of 42 tumours: 21.4%) and was associated with p16 gene (INK4A) promoter 5'-CpG islands methylation. Amplification of the cyclin D1 gene (CCND1) was detected in a small number of MGCTOs (5 of 42 tumours: 13.5%). Reduced expression of p16 due to promoter methylation correlated significantly with increased cell proliferation as evidenced by Ki-67 labelling index (p < 0.001) and mitotic index (p < 0.01). In some tumour types, nuclear localization of beta-catenin has been reported to be associated with beta-catenin gene (CTNNB1) mutation, cyclin D1 overexpression, and increased cell proliferation. Nuclear localization of beta-catenin, which was observed in MGCTOs other than dysgerminoma, was not associated with cyclin D1 expression and increased cell proliferation, but appeared to be related to tumour differentiation. Furthermore, CTNNB1 mutations were not detected in any of the MGCTOs examined. Our results suggest that reduced expression of p16 due to INK4A promoter methylation is one of the principal factors that promote cell proliferation in MGCTOs. Thus, p16 may be a novel target for gene therapies to treat MGCTOs. 相似文献
10.
Reiji Haba Shoji Kobayashi Eiichiro Hlrakawa Hiroshi Miki Takeshi Okino Tatsuo Kurokawa Syuu Yamamoto 《Pathology international》1996,46(7):515-519
An extremely rare case of malignant fibrous histiocytoma In the pancreas Is reported. A 70-year-old man complained of upper abdominal discomfort. A tumor in the head of the pancreas was demonstrated by ultrasonography and computed tomography. The surgical specimen revealed a relatively well demarcated tumor, 9 × 7 × 6.5cm in size. Microscopically, fibroblastic, histiocytic, and muitinucleated giant tumor cells were observed in the myxoid area, but some tumor cells had proliferated in a storiform-pleomorphlc pattern. Immunohtstochemically, some tumor cells were positive for lysozyme, α-1-antitrypsin, α-1-antichymotrypsin, and vimentin. Electron microscopically, tumor cells showed a combination of fibroblastic and histiocytic features. The patient Is currently well with no evidence of recurrence or metastasis 22 months after operation. 相似文献