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991.
992.
Human pancreatic kallikrein (H. Panc. K.) was purified from human pancreas by serial liquid chromatographies. The final preparation had a specific activity of 9.2 AU/A280 (AU: amidase unit for H-Pro-Phe-Arg-MCA) and its N-terminal sequence coincided with the reported sequence determined from cloned cDNA analysis. In HPLC (gel filtration), one symmetrical peak corresponding to a molecular weight of 48,000 was obtained. In SDS-PAGE without 2-mercaptoethanol, one band corresponding to a molecular weight of 52,000 was obtained. Protease inhibitor specificities of H. Panc. K. were the same as those of human urinary kallikrein (HUK) and hog pancreatic kallikrein (hog Panc. K.), while anti-HUK rabbit antibody inhibited the activities of H. Panc. K. and HUK, but not that of hog Panc. K. From the analysis of affinity for concanavalin A and erythroagglutinating phytohemagglutinin, the carbohydrate parts of H. Panc. K. are relatively rich in bi-(or multi-) antennary complex type sugar chains with bisecting GlcNAc compared with those of human salivary kallikrein and HUK. These findings will be a help to clarify the physiological and pathophysiological roles of H. Panc. K. in the pancreas and pancreatic diseases, especially in acute pancreatitis.  相似文献   
993.
A 41-year-old patient underwent surgery for the partial removal of a posterior falx meningioma, which invaded deeply into both occipital lobes. After surgery, the patient complained of marked metamorphopsia, colored photopsia, afterimage and loss of stereopsia. The relationships between these symptoms and features of the VEP and EEG power spectra (both under resting and photic driving conditions) were investigated. Marked photopsia on the 4th postoperative day was accompanied by EEG features indicating asynchronous excitation of injured cortical cells, while the presence of a strong afterimage on days 17 through 24 coincided with indications of an apparent refractoriness in cortical activation.  相似文献   
994.
The purpose of this study was to investigate the effect of repeated machining up to 51 times using the same diamond bur on machining accuracy of inner and outer surfaces of CAD/CAM (computer-aided designing and computer-aided manufacturing) machined ceramic crowns. The surface topography of machined crowns was examined using photographs. It was found that machining accuracy was not affected by the number of machining times. In all measuring points, the inner surface was machined to a dimension larger than the die model (i.e., increased gap), whereas the outer surface was machined to a dimension smaller than the crown model (i.e., smaller crown). Photo observation showed that cervical contour was machined in a clear, rounded form from 1st to 11th crowns.  相似文献   
995.
Fukuhara H  Ino Y  Kuroda T  Martuza RL  Todo T 《Cancer research》2005,65(23):10663-10668
Conditionally replicating herpes simplex virus type 1 (HSV-1) vectors are promising therapeutic agents for cancer. Certain antitumor functions may be added to oncolytic activities of recombinant HSV-1 vectors by inserting transgenes into the viral genome. Because conventional homologous recombination techniques had required time-consuming processes to create "armed" oncolytic HSV-1 vectors, we established an innovative construction system using bacterial artificial chromosome and two recombinase systems (Cre/loxP and FLPe/FRT). Using G47Delta, a safe and efficacious oncolytic HSV-1 with triple gene mutations, as the backbone, this system allowed a rapid generation of multiple vectors with desired transgenes inserted in the deleted ICP6 locus. Four oncolytic HSV-1 vectors, expressing murine interleukin 18 (mIL-18), soluble murine B7-1 [B7-1-immunoglobulin (B7-1-Ig)], both, or none, were created simultaneously within 3 months. In vitro, all newly created recombinant vectors exhibited virus yields and cytopathic effects similar to the parental G47Delta. In two immunocompetent mouse tumor models, TRAMP-C2 prostate cancer and Neuro2a neuroblastoma, the vector expressing both mIL-18 and B7-1-Ig showed a significant enhancement of antitumor efficacy via T-cell-mediated immune responses. The results show that "arming" with multiple transgenes can improve the efficacy of oncolytic HSV-1 vectors. The use of our system may facilitate the development and testing of various armed oncolytic HSV-1 vectors.  相似文献   
996.
OBJECTIVES: We recently demonstrated that papillary microcarcinomas with preoperatively detectable node metastasis in the lateral compartment on ultrasonography (clinically apparent metastasis) show worse postoperative relapse-free survival than those with no metastasis or metastasis that could not be detected preoperatively, but was confirmed by pathological examination after surgery (occult metastasis). In this study, we investigated difference in the aggressive characteristics of microcarcinoma of this type from various perspectives. MATERIALS AND METHODS: We immunohistochemically examined the expression of cell proliferating markers, Ki-67, cyclin D1, p27, and retinoblastoma gene product (pRb), apoptotic markers, single-strand DNA (ssDNA), and metastatic suppressor, kangai-1 (KAI-1) for 19 microcarcinoma patients with clinically apparent metastasis, 14 patents with occult metastasis, and 22 patients without metastasis. RESULTS: Cases of clinically apparent metastasis showed increased cyclin D1 expression together with decreased p27 expression and higher levels of pRb and Ki-67 expression. Furthermore, ssDNA expression was higher and bcl-2 expression was lower in these cases, while KAI-1 expression was significantly reduced. There was no significant difference in the expression of these proteins between cases demonstrating no and occult metastases. CONCLUSION: These findings suggest that cases of clinically apparent metastasis show significantly higher growth based on cell proliferating activity, apoptosis, and expression of metastatic suppressor than those demonstrating no or occult metastases.  相似文献   
997.
BACKGROUND: The p8 protein is involved in various cells under cellular stress, such as apoptotic stimuli. In this study, p8 protein expression was investigated in human medullary thyroid carcinoma. in order to elucidate its physiological significance. MATERIALS AND METHODS: We immunohistochemically investigated p8 expression in 69 cases of medullary thyroid carcinoma. RESULTS: Thirty cases (43.4%) were regarded as a high group of p8 expression with a labelling index of 50% or higher. The p8 expression level was directly linked to lymph node metastasis, extrathyroid extension and UICC stage. Furthermore, there were no cases showing low p8 expression, but 24.8% of those with high p8 expression showed recurrence. However, p8 expression was not linked to the apoptotic index. CONCLUSION: These findings suggest that p8 expression plays an important role in the progression of medullary carcinoma, but does not have an anti-apoptotic function.  相似文献   
998.
Here we show that human papillomavirus (HPV) E6 and E7 oncoproteins induce hWAPL expression. In addition, small interfering RNA (siRNA) of hWAPL suppressed the growth of tumours derived from SiHa cells in nude mice. Thus, hWAPL may be one of the effective targets of uterine cervical cancer therapy.  相似文献   
999.
Cancer metastasis is infrequently evaluated in vivo, probably because of the few available models and the technical challenges associated with the detection of metastases. Here we show that the growth and metastases of HT1080 fibrosarcoma, A549 lung adenocarcinoma, and RENCA murine renal cancer cell lines in five different in vivo models can be successfully monitored by labeling the cells with luciferase prior to their implantation and then detecting their bioluminesence after injecting luciferin. We also used this in vivo imaging system to successfully demonstrate that YM529, a third generation bisphosphonate, inhibited the growth of sarcoma metastases in bone. We believe the models we have established in combination with the in vivo imaging system will be highly useful for future studies of metastasis and the testing of anti-metastatic therapies.  相似文献   
1000.
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