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991.
992.
Des-gamma-carboxyprothrombin is an abnormal prothrombin which is drastically increased in the plasma of patients with hepatocellular carcinoma. To investigate the process of the abnormal prothrombin synthesis, the amount of prothrombin precursor was measured with an enzyme-linked immunosorbent assay using a specific antibody directed to human prothrombin; the vitamin-K-dependent gamma-carboxylation of prothrombin precursor was determined in human liver tissues. The tissue content of prothrombin precursor was increased in hepatoma tissues compared with noncancerous liver tissues, while the vitamin-K-dependent carboxylation of prothrombin precursor was markedly decreased in hepatoma tissues of the patients with increased plasma des-gamma-carboxyprothrombin. The present study indicates that in hepatocellular carcinoma an increase in prothrombin precursor concentration does not induce vitamin-K-dependent carboxylase activity, which is ordinarily observed in normal liver; probably an overproduction of prothrombin precursor with reduced gamma-carboxylation causes an increase in plasma des-gamma-carboxyprothrombin in patients with hepatocellular carcinoma. 相似文献
993.
The spasmolytic and antispasmodic effects of Xylocaine in different concentrations were studied. Twenty-five Wistar rats were divided into five groups according to the concentrations of Xylocaine used (2 percent, 4 percent, 10 percent, 20 percent, and 40 percent). The diameters of rat femoral arteries were measured with vernier calipers under the microscope. Effects were evaluated by the percentage of the test arterial diameter compared with that of the control contralateral artery. Vasospasm of both femoral arteries was produced by administration of the fresh blood of other rats. After immersion in the blood for 10 min. Xylocaine was administered into the right femoral artery for 10 min to examine its spasmolytic effect. The effects of the concentrations shown by the percent diameter were 106 percent, 108 percent, 107 percent, 111 percent, and 106 percent, respectively. There was no significant statistical difference between each agent and its control. Thirty minutes after removal of the agent, 2 percent Xylocaine failed to maintain its spasmolytic effect, while 4 percent, 10 percent, 20 percent, and 40 percent Xylocaine did maintain it. Next, blood was again administered after vessel immersion in the agent to examine its antispasmodic effect. The effects of the concentrations were 100 percent, 114 percent, 124 percent, 152 percent, and 146 percent. There were statistically significant differences, except in the case of 2 percent Xylocaine. Twenty-percent Xylocaine demonstrated a superior antispasmodic effect. The duration of the spasmolytic effect and the antispasmodic effect were concentration-dependent, up to approximately 20 percent. 相似文献
994.
995.
996.
Shimada S Tsuzuki T Kuroda M Nagasaka T Hara K Takahashi E Hayakawa S Ono K Maeda N Mori N Illei PB 《Pathology international》2007,57(2):60-67
Malignant peripheral nerve sheath tumor (MPNST) can be difficult to diagnose because it lacks specific immunohistochemical markers. S-100, which is a useful marker of MPNST, has limited diagnostic utility. Recent studies suggest that nestin, which is an intermediate filament protein, is expressed in neuroectodermal stem cells. The diagnostic utility of immunostains for nestin and three other neural markers (S-100, CD56 and protein gene product 9.5 (PGP 9.5)) were evaluated in 35 cases of MPNST and in other spindle cell tumors. All MPNST cases were strongly positive for nestin and had cytoplasmic staining. Stains for S-100, CD56, and PGP 9.5 were positive in fewer cases (17/35, 11/35, and 29/35 cases, respectively), and had less extensive staining. Nestin was negative in 10/10 leiomyomas, and weak nestin expression was seen in 10/10 schwannomas, 3/10 neurofibromas, 2/8 synovial sarcomas, 2/10 liposarcomas, 4/7 carcinosarcomas and 3/7 malignant fibrous histiocytomas. In contrast, strong nestin positivity was seen in 10/10 rhabdomyosarcomas, 15/19 leiomyosarcomas, and 9/9 desmoplastic melanomas. Nestin is more sensitive for MPNST than other neural markers and immunostains for nestin in combination with other markers could be useful in the diagnosis of MPNST. 相似文献
997.
998.
Sato T Amano T Ono H Ishida H Kodera H Matsumura H Yoneda M Masuda R 《Journal of human genetics》2007,52(7):618-627
In order to investigate the phylogenetic status of the Okhotsk people that were distributed in northern and eastern Hokkaido
as well as southern Sakhalin during the fifth to the thirteenth centuries, DNA was carefully extracted from human bone and
tooth remains excavated from archaeological sites. The hypervariable region 1 sequences of the mitochondrial DNA (mtDNA) control
region were successfully amplified and 16 mtDNA haplotypes were identified from 37 individuals of the Okhotsk people. Of the
16 haplotypes found, 6 were unique to the Okhotsk people, whereas the other 10 were shared by northeastern Asian people that
are currently distributed around Sakhalin and downstream of the Amur River. The phylogenetic relationships inferred from mtDNA
sequences showed that the Okhotsk people were more closely related to the Nivkhi and Ulchi people among populations of northeastern
Asia. In addition, the Okhotsk people had a relatively closer genetic affinity with the Ainu people of Hokkaido, and were
likely intermediates of gene flow from the northeastern Asian people to the Ainu people. These findings support the hypothesis
that the Okhotsk culture joined the Satsumon culture (direct descendants of the Jomon people) resulting in the Ainu culture,
as suggested by previous archaeological and anthropological studies. 相似文献
999.
Recent studies have suggested that the plasma membrane contains cholesterol-enriched microdomains known as lipid rafts. HIV-1 Gag binds raft-rich regions of the plasma membrane, and cholesterol depletion impairs HIV-1 particle production. In this study, we sought to define the block imposed by cholesterol depletion. We observed that membrane binding and higher-order multimerization of Gag were markedly reduced upon cholesterol depletion. Fusing to Gag a highly efficient, heterologous membrane-binding sequence reversed the defects in Gag-membrane binding and multimerization caused by cholesterol depletion, indicating that the impact of reducing the membrane cholesterol content on Gag-membrane binding and multimerization can be circumvented by increasing the affinity of Gag for membrane. Virus release efficiency of this Gag derivative was minimally affected by cholesterol depletion. Altogether, these results are consistent with the hypothesis that cholesterol-enriched membrane microdomains promote HIV-1 particle production by facilitating both Gag-membrane binding and Gag multimerization. 相似文献
1000.
Intracerebral haemorrhage associated with hourly concentration of ambient particulate matter: case-crossover analysis 总被引:1,自引:0,他引:1
Yamazaki S Nitta H Ono M Green J Fukuhara S 《Occupational and environmental medicine》2007,64(1):17-24