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排序方式: 共有9664条查询结果,搜索用时 15 毫秒
71.
Suda K Takase M Shiono S Yamasaki S Nobukawa B Kasamaki S Arakawa A Suzuki F 《Histopathology》2002,41(4):351-356
AIMS: To clarify the mechanism of origin of duodenal wall cysts in patients with chronic pancreatitis, developing into duodenal stenosis. METHODS AND RESULTS: Specimens from 12 pancreatoduodenectomized patients with chronic pancreatitis and 51 controls were studied histopathologically and immunohistochemically. Variously shaped cystic lesions, averaging about 15 mm in diameter, were found in the duodenum in six of the 12 patients with chronic pancreatitis, but were not observed in the controls. Each case had an average of two cysts, which were located mainly in the muscularis propria of the duodenum with or without submucosal or extraduodenal-peripancreatic extensions. The inner part of the cyst wall consisted of a moderate rim of granulation tissue, with both myofibroblasts and smooth muscle proliferation in the tissue surrounding the cyst and the submucosal layer of the duodenum, occasionally accompanied by an epithelial lining. A ductal structure in the muscularis propria of the duodenum, possibly a ductal component of ectopic pancreatic tissue, was found in five of the six cases. Some of these structures showed cystic changes. Three of the six patients had accompanying duodenal stenosis. CONCLUSIONS: Duodenal wall cysts occur mainly in the muscularis propria of the duodenum associated with both myofibroblasts and smooth muscle proliferation, and may result in duodenal stenosis. These cysts may be derived from a ductal component of ectopic pancreatic tissue. 相似文献
72.
Masaki Shiota Noriaki Tokuda Takehiro Kanou Humio Yamasaki 《Nippon Ika Daigaku zasshi》2007,74(4):306-308
Although injection-site granulomas caused by leuprorelin acetate have been reported, there have been no reports of granulomas caused by both leuprorelin acetate and goserelin acetate. An 81-year-old man presented with subcutaneous nodules of the abdominal wall and upper arm, where 11.25 mg of leuprorelin acetate had been injected for the treatment of prostate cancer. Because of these nodules, treatment was changed to goserelin acetate. Nevertheless, he presented with another subcutaneous nodule at the injection site. Histological examination showed that these nodules consisted of numerous giant cells that were CD3-positive T lymphocytes and CD68-positive histiocytes associated with granulomatous changes. The granulomas had likely been caused by delayed-type hypersensitivity to leuprorelin acetate injection. The granuloma that formed after goserelin acetate injection might thus have developed owing to the immunogenicity of the previous leuprorelin acetate injections. The patient underwent surgical castration. The present case suggests that both leuprorelin acetate and goserelin acetate can cause injection-site disorders. 相似文献
73.
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75.
Fumiyuki Yamasaki Yoshinori Kajiwara Seiji Hama Taro Murakami Toshikazu Hidaka Taiichi Saito Hiroyuki Yoshioka Kazuhiko Sugiyama Kazunori Arita Kaoru Kurisu 《Pathobiology》2007,74(1):22-31
OBJECTIVE: To investigate the mechanism of staurosporine-induced glioma cell death and cell cycle arrest using adenovirus-mediated gene transfection, as well as the function of retinoblastoma (Rb) and genetic instability induced by staurosporine. METHODS: Cell cycle regulation, cell death and nuclear abnormalities induced by staurosporine were examined using an adenovirus vector expressing Rb, p16 or p21 genes in human glioma cell lines. RESULTS: The Rb-defective SF-539 cell line was resistant to staurosporine compared with cell lines expressing intact Rb. SF-539 glioma cells exposed to staurosporine became multinucleated and then died. Multinucleation was prevented in SF-539 cells transfected with the Rb gene, thus decreasing the death rate of these cells. CONCLUSIONS: These results imply that enforced Rb expression protects cells from genomic instability induced by staurosporine regardless of its upstream molecular effects. 相似文献
76.
Satoshi Muraki Masahiro Yamasaki Yoshito Ehara Kunio Kikuchi Kunihiro Seki 《European journal of applied physiology》1996,74(5):481-483
The purpose of the present study was to examine the effect of maximal arm exercise on the skin blood circulation of the paralyzed
lower limbs in persons with spinal cord injury (PSCI). Eight male PSCI with complete lesions located between T3 and L1 performed
graded maximal arm-cranking exercise (MACE) to exhaustion. The skin blood flux at the thigh (SBFT) and that at the calf (SBFC)
were monitored using laser-Doppler flowmeter at rest and for 15 s immediately after the MACE. The subject's mean peak oxygen
uptake and peak heart rate was 1.41 ± 0.22 l · min–1 and 171.6 ± 19.2 beats · min–1, respectively. No PSCI showed any increase in either SBFT or SBFC after the MACE, when compared with the values at rest.
These results suggest that the blood circulation of the skin in the paralyzed lower limbs in PSCI is unaffected by the MACE.
Accepted: 12 September 1996 相似文献
77.
Ramp rate of blood pressure changes does not affect aortic afferent sensitivity in anesthetized rats
Hidefumi Waki Tsuyoshi Shimizu Masao Yamasaki Kiyoaki Katahira Shinichiro Katsuda Jaimie W. Polson Masanobu Maeda 《Neuroscience letters》2008
To investigate whether the rate of change in blood pressure affects the sensitivity of the aortic baroreceptor afferent response, the change in aortic nerve activity (ANA) to two different rates of ramp increase in mean blood pressure (MBP), elicited by phenylephrine administration, was determined in the rat under urethane (1.5 g kg−1) anesthesia. The sensitivity of the increase in ANA following a rapid (average ramp rate, 9.14 ± 0.60 mmHg s−1, n = 11) or gradual (1.78 ± 0.24 mmHg s−1, n = 11) increase in MBP was 2.03 ± 0.14% and 1.81 ± 0.20% of baseline mmHg−1, respectively. These values were not significantly different from each other (P = 0.16). Furthermore, we found no correlation between the rate of ramp increase in MBP and the sensitivity of the increase in ANA (r = 0.24, P = 0.29, n = 22). These results suggest that, at least within the normal physiological range of MBP, the rate of the ramp change in blood pressure does not affect aortic baroreceptor afferent sensitivity in the anesthetized rat. 相似文献
78.
Takaaki Hayashi Katsuhiro Hosono Akiko Kubo Kentaro Kurata Satoshi Katagiri Kei Mizobuchi Minehiro Kurai Norihito Mamiya Mineo Kondo Toshiaki Tachibana Hirotomo Saitsu Tsutomu Ogata Tadashi Nakano Yoshihiro Hotta 《American journal of medical genetics. Part A》2020,182(6):1500-1505
Mucolipidosis type IV (MLIV) is an autosomal recessively inherited lysosomal storage disorder characterized by progressive psychomotor delay and retinal degeneration that is associated with biallelic variants in the MCOLN1 gene. The gene, which is expressed in late endosomes and lysosomes of various tissue cells, encodes the transient receptor potential channel mucolipin 1 consisting of six transmembrane domains. Here, we described 14‐year follow‐up observation of a 4‐year‐old Japanese male MLIV patient with a novel homozygous in‐frame deletion variant p.(F313del), which was identified by whole‐exome sequencing analysis. Neurological examination revealed progressive psychomotor delay, and atrophy of the corpus callosum and cerebellum was observed on brain magnetic resonance images. Ophthalmologically, corneal clouding has remained unchanged during the follow‐up period, whereas optic nerve pallor and retinal degenerative changes exhibited progressive disease courses. Light‐adapted electroretinography was non‐recordable. Transmission electron microscopy of granulocytes revealed characteristic concentric multiple lamellar structures and an electron‐dense inclusion in lysosomes. The in‐frame deletion variant was located within the second transmembrane domain, which is of putative functional importance for channel properties. 相似文献
79.
Tsuneyuki Sato Kentaro Toyosu Hitoshi Tanaka 《Macromolecular chemistry and physics.》1993,194(10):2797-2805
The system of lanthanum versatate ( 1 ) and p-chlorobenzenediazonium tetrafluoroborate ( 2 ) was found to induce effectively polymerizations of electron-accepting monomers such as methyl methacrylate ( 3 ) and di-2-ethylhexyl itaconate (DEHI). The polymerization rate (Rp) was expressed by Rp = k[ 1 / 2 ]0,44 [ 3 ]0,65 at 50°C fixing the mole ratio of 1 and 2 at unity. The overall activation energy of the polymerization was calculated to be 37, 1 kJ · mol?1. The spin trapping result revealed that the initiator system produces p-chloropheneyl radicals. The polymerization system of DEHI was observed to involve ESR-observable propagating polymer radicals, indicating that the polymerization initiated with the 1/2 system proceeds through radical mechanism. During the polymerization, the ESR spectrum was changed in shape, suggesting that the propagating polymer radicals interact with some species formed by the initiation reaction. Interacting polymer radicals were also observed in the polymerizations of diethyl itaconate and N-dodecylmaleimide with the 1/2 system. The polymerization systems of MMA, styrene and butyl acrylate were also found to involve ESR-observable radicals, although it is vague whether they are propagating polymer radicals or not. 相似文献
80.
The prevalence of TT virus (TTV) infection and its relationship to hepatitis in children 总被引:4,自引:0,他引:4
Iriyama M Kimura H Nishikawa K Yoshioka K Wakita T Nishimura N Shibata M Ozaki T Morishima T 《Medical microbiology and immunology》1999,188(2):83-89
TT virus (TTV) is a newly discovered virus from a patient with post-transfusion hepatitis. We investigated the frequency
and pathogenesis of TTV infection in children. A semi-nested PCR assay was used to amplify TTV-DNA in serum samples from 254
ambulatory children without liver disease, 20 with hepatitis of unknown etiology, and 18 transfusion recipients or hemophiliacs.
In positive samples, TTV-DNA was quantified by real-time quantitative PCR using a fluorescent probe. We detected TTV-DNA in
20% of children with hepatitis of unknown etiology, which was not statistically different from the 23% prevalence in ambulatory
children. In transfusion recipients or hemophiliacs, the frequency was higher (50%) than that in ambulatory children (P = 0.01). Among ambulatory children, TTV-DNA was frequently detected in children with acute gastroenteritis (36%). TTV-DNA
was detected in 10% of the infants under 6 months old, and 20% of the children from 7 to 12 months old. The prevalence was
constant after the age of 1 year; however, the copy number of TTV-DNA was significantly higher in children under 1 year of
age (mean: 105.4 versus 103.8 copies/ml, P= 0.008). Finally, TTV-DNA was quantified serially in three children with chronic hepatitis who were positive for TTV-DNA.
The presence or amount of TTV-DNA was unrelated to the serum alanine aminotransferase level. These results indicate that TTV
infection is common in children. The larger quantity of TTV-DNA in infants and the high prevalence of TTV in children of all
ages suggest that TTV may be transmitted in early childhood. Its relationship to hepatitis is doubtful in children.
Received: 8 April 1999 相似文献