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21.
Primary prostate epithelial and prostate adenocarcinoma cells cultured in serum-free medium grew for up to 10 passages before senescence. Cells from prostate adenocarcinoma of a 55-year-old patient without lymph node involvement were transfected with plasmids containing recombinant human papilloma virus HPV16 or HPV18 DNA and the selectable neomycin-resistance gene. After G-418 selection, cells underwent crisis, and surviving cells infected with retroviruses encoding the HPV18 E6/E7 genes (HPV-PAC1), transfected with a head-to-tail dimer of the complete HPV16 genome (HPV-PAC2), or transfected with HPV18 E6/E7 early genes (HPV-PAC3) were established. HPV-PAC1 and HPV-PAC2 cultures appeared morphologically similar to primary cultures even after 40 passages. However, HPV-PAC2 cultures had a clonal morphology. All lines were positive for cytokeratin 18, had acquired vimentin expression, and contained either HPV16 or HPV18 sequences integrated into host DNA. None was tumorigenic in nude mice or formed colonies in soft agar. These cells did not secrete prostate specific antigen nor respond to androgen although tamoxifen inhibited the growth of the cells. Immunohistochemistry showed no evidence of p53 overexpression. Further characterization of these cell lines and examination of their response to chemotherapeutic agents may provide relevant information for the study of hormone-independent PC.  相似文献   
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l-Carnitine is required for mitochondrial fatty acid oxidation, but the effects of carnitine supplementation on nutrient metabolism during dry matter intake depression have not been determined in dairy cows. Studies in other species have revealed responses to l-carnitine that may be of specific benefit to dairy cows during the periparturient period. Eight lactating Holstein cows (132 ± 36 d in milk) were used in a replicated 4 × 4 Latin square experiment with 14-d periods. Treatments were factorial combinations of abomasal infusion of either water or l-carnitine (20 g/d; d 5 to 14) and either ad libitum or restricted intake (50% of previous 5-d dry matter intake; d 10 to 14) of a balanced lactation diet. Liver and muscle biopsies were obtained on d 14 of each period. Feed restriction induced negative balances of energy and metabolizable protein. In feed-restricted cows, carnitine infusion increased 3.5% fat-corrected milk yield compared with those infused with water. Total carnitine concentration in liver was increased in feed-restricted cows infused with carnitine but not in feed-restricted cows infused with water. Carnitine infusion stimulated in vitro oxidation of [1-14C] palmitate to acid-soluble products and decreased the proportion of [1-14C] palmitate that was converted to esterified products by liver slices. Feed-restricted cows infused with carnitine had lower liver total lipid concentration and tended to have decreased triglyceride accumulation compared with feed-restricted cows infused with water. Plasma nonesterified fatty acid concentration was not altered by carnitine infusion but was increased by feed restriction; serum β-hydroxybutyric acid was increased by carnitine infusion in feed-restricted cows. In cows fed for ad libitum intake, carnitine infusion affected β-hydroxybutyric acid, insulin, and urea N in serum, liver glycogen concentration, and in vitro alanine oxidation by liver slices, suggesting that hepatic and peripheral nutrient metabolism was influenced. l-Carnitine infusion effectively decreased liver lipid accumulation during feed restriction as a result of greater capacity for hepatic fatty acid oxidation. Further research examining dietary supplementation of l-carnitine during the periparturient period is warranted.  相似文献   
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Virtual Reality - A “virtual mirror” is a promising interface for virtual or augmented reality applications in which users benefit from seeing themselves within the environment, such as...  相似文献   
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A number of details are clarified regarding the sampling-reconstruction theorem for near-field scanning in plane-polar coordinates. The rigorous sampling-reconstruction theorem is applied to the near-field measurement of a circular aperture test antenna offset from the plane-polar axis of rotation, so that a large number of angular modes are necessary to represent the fields of the test antenna. An algorithm is described for computing accurately and rapidly the required zeros of Bessel functions of arbitrary integer order  相似文献   
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Transfection of the right end Xho2 subfragment of Bg/II N of herpes simplex virus-2 (HSV-2) into human genital keratinocytes immortalized by human papillomavirus (HPV) type 16 or 18 resulted in invasive and noninvasive indolent cystic squamous carcinomas when cells were injected into immunocompromised mice. Retention and expression of the right end portion of the Bg/II N fragment correlated with malignancy, as the corresponding HSV-2 sequences were integrated and transcribed in the tumorigenic cell lines. HPV-immortalized cells alone were not tumorigenic. In contrast, previous results have shown that using the entire Bg/II N region can malignantly transform HPV-immortalized cells, although HSV2 DNA was not retained. Together, these observations localize the transforming activity of Bg/II N to Xho2 and suggest that the remaining sequences have an inhibitory effect on stable integration. The Xho2 sequence is 2480 bp long and contains an open reading frame (ORF) extending from nucleotides 559 to 1797. The ORF encodes a putative protein of 412-aa with a m.w. of 42-43 kDa and is highly homologous to UL43 of HSV-I. The correlation of tumorigenicity with stable integration and expression of Xho2 DNA in HPV-immortalized cells indicates that HSV-2 should be investigated further for a possible role in cervical cancer.  相似文献   
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This study investigated the relationship between psychopathy and the characteristics of criminal homicides committed by a sample of 125 Canadian offenders. It was hypothesized that the homicides committed by psychopathic offenders would be more likely to be primarily instrumental (i.e., associated with premeditation, motivated by an external goal, and not preceded by a potent affective reaction) or "cold-blooded" in nature, whereas homicides committed by nonpsychopaths often would be "crimes of passion" associated with a high level of impulsivity/reactivity and emotionality. The results confirmed these predictions; homicides committed by psychopathic offenders were significantly more instrumental than homicides by nonpsychopaths. Nearly all (93.3%) of the homicides by psychopaths were primarily instrumental in nature compared with 48.4% of the homicides by nonpsychopaths. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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空穴注入层技术可降低OLED成本和提高其生产效率,是使柔性OLED显示成为商品化的一个重要因素。  相似文献   
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We describe the theory, design and ongoing prototyping of a wireless ATM LAN/PBX capable of supporting mobile users with multi-Mb/s access rates and multi-Gb/s aggregate capacities. Our proposed LAN Consists of network nodes called Portable Base Stations (PBS) providing microcell coverage. The PBSs are designed to be low-cost, compact and high-speed and can be relocated conveniently. We employ a concept ofad-hoc networking in the layout of the PBS-to-PBS interconnection. That is, the PBSs can be distributed in an arbitrary topology to form a backbone network and can be reconfigured with relative ease. The PBS-to-PBS backbone links are high-speed (Gb/s) for supporting high system capacity. Although they can either be wired or wireless, our emphasis is on wireless implementations. The user-to-PBS links, on the other hand, are primarily for mobile access (e.g., 2–20 Mb/s) and therefore are wireless. Wired connections from stationary users to PBSs are also possible. Typical mobile users are assumed to be laptops or notebook computers. Services supported include conventional data applications (e.g., over TCP/IP or SPX/IPX) as well as multimedia (video, voice and data) applications with QoS (Quality-of-Service) guarantees. A wireless ATM concept is proposed so as to provide seamless internetworking with other wired ATM local and wide-area net-works. Algorithms and control in our network are highly distributed for simple implementations and ease of mobility management. A new wireless VP/VC concept and a Homing Algorithm are described to provide ATM cell routing and connections in the network. PBS hardware and software architectures are discussed. Call management, network management and signaling are designed for simplicity, high performance and modular implementations. A fast network restoration scheme is proposed to cope with the potential link or node failures in the ad-hoc network. Error control is addressed taking the unreliable wireless links into consideration. Finally, a prototyping project called BAHAMA (Broadband Ad Hoc ATM Anywhere) for demonstrating this network concept is briefly outlined.  相似文献   
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