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41.
Naoko Masuzawa Mitsuo Kishimoto Yoshiki Takahashi 《International journal of gynecological pathology》2003,22(3):285-288
A 57-year-old female presented with an abnormal Pap smear. Colposcopic examination of the cervix revealed white mucosa with erosion and several areas of black pigmentation. After a colposcopically directed biopsy and loop conization, radical hysterectomy and bilateral salpingo-oophorectomy with pelvic and paraaortic lymphadenectomy were performed. Pathological examination disclosed an invasive squamous cell carcinoma admixed with many dendritic melanocytes. Melanin granules were present within the melanocytes and tumor cells. Although similar tumors have been reported in other sites, this is the first report to our knowledge of a pigmented squamous cell carcinoma of the uterine cervix. 相似文献
42.
Naoya Katsuragi Yutsuki Nakajima Yuji Shiraishi Masahiro Hashizume Nobumasa Takahashi 《The Japanese Journal of Thoracic and Cardiovascular Surgery》2005,53(8):440-442
We describe a case of a large bronchial fistula and empyema after right upper lobectomy that was treated successfully with
open window thoracostomy followed by a latissimus dorsi myocutaneous flap and limited thoracoplasty. A latissimus dorsi myocutaneous
flap can provide immediate airtight closure of a large bronchial fistula, allowing lavage and curettage of the empyema cavity
to reduce the chance of postoperative infection. An important aspect of this technique is that the deepithelialized skin side
rather than muscle is sutured to an opening of the bronchus. As compared with other techniques, a latissimus dorsi myocutaneous
flap is superior in that it requires a single incision and does not require an intraop-erative change of position. In addition,
the technique causes little dysfunction of the chest and shoulder and preserves the vascular supply to ensure the viability
of the flap even if it was divided in a previous operation. 相似文献
43.
Takuya Toyama Norihiko Ohura Masakazu Kurita Akira Momosawa Kiyonori Harii 《Nordisk plastikkirurgisk forening [and] Nordisk klubb for handkirurgi》2006,40(6):329-334
We have investigated the effects of short-contact topical application of tretinoin using 16 male db/db mice by creating two full-thickness wounds on the skin of the back. A 0.1% tretinoin aqueous gel was applied to one wound for five minutes daily for five successive days while only aqueous gel was applied to the other (control). The mean (SD) percentage surface area unhealed before and after treatment were 0.88 (0.3) and 0.64 (0.15). In tretinoin-treated mice and non-treated mice (controls), the mean (SD) thicknesses of granulation were 1.383 (697) micro m and 683 (413) micro m, the density of capillary vessels in granulation was 12.2 (5.5)% and 5.7 (3.9)%, respectively. Differences between the two groups were significant for each variable. Wound healing was accelerated with short-contact topical application of tretinoin in db/db mice. 相似文献
44.
Yu-Yan Fan Ryoko Baba Yukiko Nagai Akira Miyatake Naohisa Hosomi Shoji Kimura Guang-Ping Sun Masakazu Kohno Mamoru Fujita Youichi Abe Akira Nishiyama 《Hypertension research》2006,29(3):169-178
Recent studies have suggested that aldosterone plays a role in the pathogenesis of renal injury. In this study, we investigated whether local angiotensin II (Ang II) activity contributes to the progression of renal injury in aldosterone/salt-induced hypertensive rats. Uninephrectomized rats were treated with 1% NaCl in a drinking solution and one of the following combinations for 6 weeks: vehicle (2% ethanol, s.c.; n=9), aldosterone (0.75 mug/h, s.c.; n=8), aldosterone+Ang II type 1 receptor blocker olmesartan (10 mg/kg/day, p.o.; n=8), or aldosterone+olmesartan (100 mg/kg/day, p.o.; n=9). Aldosterone/salt-treated hypertensive rats exhibited severe proteinuria and renal injury characterized by glomerular sclerosis and tubulointerstitial fibrosis. Aldosterone/salt-induced renal injury was associated with augmented expression of angiotensin converting enzyme and Ang II levels in the renal cortex and medullary tissues. Renal cortical and medullary mRNA expression of transforming growth factor-beta (TGF-beta) and connective tissue growth factor (CTGF) as well as the collagen contents were increased in aldosterone/salt-treated hypertensive rats. Treatment with olmesartan (10 or 100 mg/kg/day) had no effect on blood pressure but attenuated proteinuria in a dose-dependent manner. Olmesartan at 10 mg/kg/day tended to decrease renal cortical and medullary Ang II levels, TGF-beta and CTGF expression, and collagen contents; however, these changes were not significant. On the other hand, an ultrahigh dose of olmesartan (100 mg/kg/day) significantly decreased these values and ameliorated renal injury. These data suggest that augmented local Ang II activity contributes, at least partially, to the progression of aldosterone/salt-dependent renal injury. 相似文献
45.
46.
p53 mutations in non-small cell lung cancer in Japan: association between mutations and smoking. 总被引:20,自引:0,他引:20
H Suzuki T Takahashi T Kuroishi M Suyama Y Ariyoshi T Takahashi R Ueda 《Cancer research》1992,52(3):734-736
The p53 gene has been implicated as a tumor suppressor gene involved in the pathogenesis of lung cancer. Our previous study revealed that the p53 gene is frequently mutated with a distinct nucleotide substitution pattern in small cell lung cancer specimens in Japanese patients. In this study, we examined 30 primary, resected non-small cell lung cancer samples in Japanese patients using complementary DNA-polymerase chain reaction and sequencing. Mutations changing the p53 coding sequence were found in 14 of 30 tumor samples (47%), while G:C to T:A transversions which are uncommon in other cancers such as colon cancer were the most frequently observed mutations, in agreement with an earlier report on non-small cell lung cancer in American patients. Furthermore, the present study shows for the first time that in univariate and multivariate analyses, the presence of p53 mutations is closely associated with lifetime cigarette consumption. 相似文献
47.
A Nishikawa F Furukawa M Mitsui T Enami T Kawanishi T Hasegawa M Takahashi 《Carcinogenesis》1992,13(7):1155-1158
The effects of calcium chloride on glandular stomach carcinogenesis induced by N-methyl-N'-nitro-N-nitrosoguanidine (MNNG) and sodium chloride were investigated in male outbred Wistar rats. Animals were given MNNG solution (100 p.p.m.) as drinking water and simultaneously fed a diet supplemented with 5% sodium chloride for 8 weeks. Matched negative controls received neither MNNG nor sodium chloride. Rats were then fed basal diet and given calcium chloride solution (1 or 0.2%) or tap water for the following 52 weeks. The incidences and multiplicities of preneoplastic hyperplasias in the glandular stomachs of rats given MNNG/sodium chloride followed by 1 and 0.2% calcium chloride were significantly lower than those in rats given MNNG/sodium chloride alone. The inhibitory effects of calcium were exerted in a dose-dependent manner. Calcium treatment also showed a tendency to inhibit the development of gastric adenocarcinomas although this was not statistically significant. Rats without carcinogen treatment had neither carcinomas nor preneoplastic hyperplasias in the glandular stomach. Calcium intake also significantly reduced the levels of malondialdehyde, a measure of lipid peroxidation, in the gastric mucosa and urine, the former in a dose-dependent manner. Thus, calcium chloride exerted inhibitory effects when given during the post-initiation phase of two-stage glandular stomach carcinogenesis in rats. 相似文献
48.
Epirubicin is equivalent to adriamycin in vitro against many cancer cells but more effective against gastric cancer cells. 总被引:1,自引:0,他引:1
We compared the cytotoxic effects of two anthracycline derivatives, epirubicin (EPI) and adriamycin (ADM), against human tumor cells in vitro. Various tumor specimens, obtained at surgery, included 57 liver, 19 lung, 16 gastric, 10 colorectal and 7 breast cancer specimens. These tumor cells were exposed to the same concentration of EPI or ADM for 3 days. The chemosensitivity of each tumor cell type to each drug was then assayed using the in vitro succinate dehydrogenase inhibition (SDI) test. Sensitivity to the treatment was defined as a 50% or greater reduction in the succinate dehydrogenase (SD) activity of the tumor cells, relative to that of the control (untreated) cells. Each cell type, except for gastric cancer cells, was equally sensitive to EPI and ADM. Gastric cancer cells were more sensitive to EPI than to ADM (P less than 0.05). The rate of coincidence, the sum of the co-sensitive and co-resistant rates of all the tumors, was quite high (90.8%). Thus, these findings indicate that EPI and ADM are equally cytotoxic to each tumor cell type, but EPI is more cytotoxic than ADM to gastric cancer cells. Since EPI is reported to be less cardiotoxic than ADM, EPI may replace ADM in cancer chemotherapy. 相似文献
49.
A Nishikawa F Furukawa T Imazawa H Yoshimura K Mitsumori M Takahashi 《Carcinogenesis》1992,13(8):1379-1382
The modulating effects of caffeine, nicotine, ethanol and sodium selenite on development of N-nitrosobis(2-oxopropyl)-amine (BOP)-initiated pancreatic tumors were investigated. Female Syrian golden hamsters were given s.c. injections of BOP (10 mg/kg body weight) or saline alone once a week for 3 weeks and then administered 2000 p.p.m. caffeine, 25 p.p.m. nicotine, 20% ethanol or 4 p.p.m. sodium selenite in their drinking water for the next 37 weeks. Control animals were given tap water alone after BOP initiation. Only the BOP-treated groups developed pancreatic adenocarcinomas and dysplasias. The multiplicity of pancreatic carcinomas was significantly higher (P less than 0.05) in animals receiving caffeine than in the controls. In addition, caffeine treatment slightly increased the incidence of carcinomas. Nicotine and ethanol also showed tendencies to enhance pancreatic carcinogenesis, although there were statistically no significant differences regarding lesion development. In contrast, sodium selenite administration was associated with a tendency for a decrease in the number of carcinomas and dysplasias. Thus, among these chemicals of obvious significance to human life-style, caffeine enhanced the development of pancreatic tumors when administered during the post-initiation phase in this hamster model. 相似文献
50.