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排序方式: 共有9662条查询结果,搜索用时 11 毫秒
11.
Hiroyuki Yamamoto Fumio Itoh Akinori Senota Yasushi Adachi Mitsuru Yoshimoto Takao Endoh Yuji Hinoda Akira Yachi Kohzoh Imai 《Journal of clinical laboratory analysis》1995,9(5):297-301
The matrix metalloproteinase matrilysin (MMP-7) is a member of the matrix metallo-proteinase gene family, which is believed to play an important role in tumor invasion and metastasis. We have previously found that matrilysin mRNA is specifically expressed in colorectal cancers and adenomas and that its message is localized in the tumor cells themselves. We examined the effects of activated Ki-ras oncogene on the expression of matrilysin in colon cancer cells. We showed that both mRNA and the enzymatic activity of matrilysin were induced by the introduction of activated Ki-ras into SW1417 colon cancer cells. To understand the mechanisms regulating this induction, we analyzed alterations of AP-1 activity induced by activated Ki-ras, using the chloramphenicol acetyltransferase assay. AP-1 activity in SW1417 cells expressing activated Ki-ras was higher than that in control cells. The gel-shift assay also showed higher levels of AP-1 binding protein in SW1417 cells expressing activated Ki-ras than those in control cells. Our results suggest that activated Ki-ras may play a role in inducing expression of matrilysin through an AP-1-dependent pathway in colon cancer cells. 相似文献
12.
A Tsuji M Takao T Asano T Fujioka H Nakamura K Mukai 《Hinyokika kiyo. Acta urologica Japonica》1987,33(5):738-742
A black adenoma of the adrenal cortex was surgically removed from an 18-year-old female who had clinical and laboratory findings characteristic of Cushing's syndrome. The electron microscopic study revealed typical features of steroid-producing cells, including a prominent smooth and rough endoplasmic reticulum, and mitochondria. In addition, many of the adenoma cells contained numerous pigmented granules which were lipofuscin. Three months after the surgery, the hormone levels returned to the normal range. The Japanese literature of functional black adenoma is reviewed. 相似文献
13.
Reviewing the definition of "elderly" 总被引:1,自引:0,他引:1
Hajime Orimo Hideki Ito Takao Suzuki Atsushi Araki Takayuki Hosoi Motoji Sawabe 《Geriatrics & Gerontology International》2006,6(3):149-158
Conventionally, "elderly" has been defined as a chronological age of 65 years old or older, while those from 65 through 74 years old are referred to as "early elderly" and those over 75 years old as "late elderly." However, the evidence on which this definition is based is unknown. We have attempted to review the definition of elderly by analyzing data from long-term longitudinal epidemiological studies, and clinical and pathological studies that have been accumulated at the Tokyo Metropolitan Geriatric Hospital and the Tokyo Metropolitan Institute of Gerontology. Our recommendation might be a starting point in developing a strategy for a successful society by reviewing the definition of elderly based on comprehensive evidence in all aspects of social, cultural and medical sciences. 相似文献
14.
Kiichiro Hashimoto Naohide Mori Takao Tamesa Toshimasa Okada Shigeto Kawauchi Atsunori Oga Tomoko Furuya Akira Tangoku Masaaki Oka Kohsuke Sasaki 《Modern pathology》2004,17(6):617-622
To clarify the genetic aberrations involved in the development and progression of hepatitis C virus-associated hepatocellular carcinoma (HCV-HCC), we investigated DNA copy number aberrations (DCNAs) in 19 surgically resected HCCs by conventional CGH and array CGH. Conventional CGH revealed that increases of DNA copy number were frequent at 1q (79% of the cases), 8q (37%), 6p (32%), and 10p (32%) and that decreases were frequent at 17p (79%), 16q (58%), 4q (53%), 13q (42%), 10q (37%), 1p (32%), and 8p (32%). In general, genes that showed DCNAs by array CGH were usually located in chromosomal regions with DCNAs detected by conventional CGH analysis. Increases in copy numbers of the LAMC2, TGFB2, and AKT3 genes (located on 1q) and decreases in copy numbers of FGR/SRC2 and CYLD (located on 1p and 16q, respectively) were observed in more than 30% of tumors, including small, well-differentiated carcinomas. These findings suggest that these genes are associated with the development of HCV-HCC. Increases of MOS, MYC, EXT1, and PTK2 (located on 8q) were detected exclusively in moderately and poorly differentiated tumors, suggesting that these alterations contribute to tumor progression. In conclusion, chromosomal and array CGH technologies allow identification of genes involved in the development and progression of HCV-HCC. 相似文献
15.
M Takao K Nagakura S Shimizu K Kawabata F Kimura M Sawamura T Asano K Odajima F Nakajima K Ieda 《Hinyokika kiyo. Acta urologica Japonica》1990,36(10):1163-1166
Absorption of tetrahydropyranyl adriamycin (THP) administered immediately after transurethral resection of bladder carcinoma (TUR-Bt) has not been reported. In this study, we have examined the absorption of THP and the systemic toxicity in the early post-TUR period. Of 21 patients with bladder carcinoma, 10 had a solitary tumor and 11 multiple tumors. Twenty mg THP in 40 ml of sterile water was intravesically administered on days 1, 3, 5, 7, 14 and 28, and then every 4th week. The THP solution was retained for 2 hours. The blood THP concentration was measured 30 minutes and 2 hours after the intravesical administration on days 1, 7 and 28. No systemic side effects were observed. Thirteen of the 38 (34%) samples contained a detectable level (more than 1 ng/ml) of THP on the post-TUR-Bt on day 1, 8, of 42 (19%) on day 7, and 3 of 18 (17%) on day 28. Altogether, 24 of the 98 (24%) samples contained more than 1 ng/ml THP. The highest blood THP level was 23 ng/ml on day 1. The differences between frequency of detection of blood THP in the samples at 30 minutes and 2 hours were not statistically significant. The difference between average concentration of blood THP of patients with solitary and multiple tumors also was not significant. These results indicate that intravesical THP administration starting within 24 hours after TUR-Bt can not result in significant systemic absorption of THP, and the systemic toxicity can be avoided. 相似文献
16.
Tetsuhiko Nagao Seizo Sadoshima Takao Ishitsuka Kenji Kusuda Osamu Shiokawa Setsuro Lbayashi Masatoshi Fujishima 《Clinical and experimental pharmacology & physiology》1992,19(7):489-493
1. The effects of acute bilateral superior cervical ganglionectomy on cerebral blood flow and metabolism were investigated in stroke-prone spontaneously hypertensive rats (SHRsp), before and during cerebral ischaemia. 2. The resting cerebral blood flow was comparable between the control and denervated animals. 3. There was no significant difference in cerebral blood flow or concentration of tissue energy metabolites (adenosine triphosphate [ATP], lactate and pyruvate) between the sham-operated control and denervated animals during ischaemia. 4. The results suggest that sympathetic innervation of cerebral vessels originating from superior cervical ganglia may not play a major role in the progression of cerebral ischaemia in SHRsp. 相似文献
17.
18.
Takao Hashimoto Osamu Sasaki Kunihiro Yoshida Yo-ichi Takei Shu-ichi Ikeda 《Movement disorders》2003,18(10):1201-1204
We report on a family with ataxia type 6 (SCA6) showing peculiar oculomotor symptoms. The proband presented with periodic alternating nystagmus (PAN), and her 2 brothers had rebound nystagmus and gaze-evoked nystagmus. They carried the identical mutation (the number of expanded CAG repeat, 24) in the CACNA1A gene. The intrafamilial variability of oculomotor symptoms may be ascribed to factors other than CAG repeat expansion size in SCA6. 相似文献
19.
β2-glycoprotein-I (β2GPI) is a phospholipid-binding plasma protein that consists of five homologous domains. Domain V is distinguished from others by bearing a positively charged lysine cluster and hydrophobic extra C-terminal loop. β2GPI has been known as a natural anticoagulant regulator. β2GPI exerts anticoagulant activity by inhibition of phospholipid-dependent coagulation reactions such as prothrombinase, tenase, and factor XII activation. It also binds factor XI and inhibits its activation. On the other hand, β2GPI inhibits anticoagulant activity of activated protein C. According to the data from knockout mice, β2GPI may contribute to thrombin generation in vivo. Phospholipid-bound β2GPI is one of the major target antigens for antiphospholipid antibodies present in patients with antiphospholipid syndrome (APS). Binding of pathogenic anti-β2GPI antibodies increases the affinity of β2GPI to the cell surface and disrupts the coagulation/fibrinolysis balance on the cell surface. These pathogenic antibodies activate endothelial cells via signal transduction events in the presence of β2GPI. Impaired fibrinolysis has been reported in patients with APS. Using a newly developed chromogenic assay, we demonstrated lower activity of intrinsic fibrinolysis in euglobulin fractions from APS patients. Addition of monoclonal anti-β2GPI antibodies with β2GPI also decreased fibrinolytic activity in this assay system. β2GPI is proteolytically cleaved by plasmin in domain V (nicked β2GPI) and becomes unable to bind to phospholipids, reducing antigenicity against antiphospholipid antibodies. This cleavage occurs in patients with increased fibrinolysis turnover. Nicked β2GPI binds to plasminogen and suppresses plasmin generation in the presence of fibrin, plasminogen, and tissue plasminogen activator (tPA). Thus, nicked β2GPI plays a role in the extrinsic fibrinolysis via a negative feedback pathway loop. 相似文献
20.
Takuo Fujita Masaaki Fukase Takao Shimada Hironosuke Yamamoto 《Journal of bone and mineral metabolism》1992,10(1):37-40
In addition to estrogen widely used all over the world for the prevention of postmenopausal osteoporosis, calcitonin and vitamin
D derivatives are commonly employed to treat established osteoporosis at higher age in Japan. In order to critically assess
the usefulness of vitamin D derivatives and calcitonin alone or in combination on the advancement of vertebral deformity at
higher age, 32 osteoporotic patients with vertebral deformity with the mean age of 79 were randomly divided into 4 groups
with indistinguishable age and severity of the vertebral deformity. Group 1 served as the control without specific medications
for osteoporosis. Group 2 was treated with 10 units elcatonin (eel calcitonin derivative) injected intramuscularly twice a
week. Group 3 was given 0.75 to 1.5μg/day 1α (OH) vitamin D3 orally. Group 4 was given a combination of treatments used in Groups 2 and 3.
In the lateral X-ray film of the spine taken prior to the test and every 6 months thereafter, the shape of the vertebral body
T8 through L4 was monitored by measuring the anterior, central and posterior heights. Decrease of the vertebral height ratio; anterior
or middle height/posterior or adjacent intact posterior height, by more than 20% of the original value or from above to below
0.80 both appeared to be inhibited during administration of 1α (OH) vitamin D3. Such effect seems to be augmented by simultaneous administration of elcatonin. Actual decrease of vertebral height ratio
values and the per cent fall from the original value significantly less in Groups 3 and 4 than in Group 1. Development of
vertebral deformity assessed by the changes of the vertebral height thus appears to decrease during treatment with 1α (OH) vitamin D3 especially together with calcitonin in established osteoporosis. 相似文献