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101.
Long-term ultraviolet-light (UV) exposure of human skin epidermis is associated with an increased risk for the development of skin cancers, such as melanoma, basal cell carcinoma (BCC) and squamous cell carcinoma (SCC). UV radiation not only induces DNA damage in epidermal cells, it also interferes with skin homeostasis, which is maintained by a unique distribution pattern of apoptosis-inducing and -preventing molecules. If the DNA damage is not repaired or the damaged cells are not eliminated by apoptosis, the consequence can be cell transformation, uncontrolled proliferation and eventually skin tumor formation. An important "repair" gene is the p53 suppressor gene. Excessive UV exposure can mutate the p53 gene leading to the loss of its repair function and thus apoptosis resistance of the DNA-damaged cell. For BCC formation an additional pathway has been identified. Mutation of genes of the Hedgehog signaling pathway evokes the downregulation of apoptotic genes and upregulation of anti-apoptotic genes preventing the elimination of damaged cells. In addition, BCC and SCC strongly express the apoptosis-inducing Fas-ligand (FasL) which may help the tumor to escape the attack of immune effector cells. Silencing the genes involved in tumor formation by RNA interference might become a promising new approach to treat skin tumors. 相似文献
102.
Takeda H Matsumura Y Kuwata S Nakano H Shanmai J Qiyan Z Yufen C Kusuoka H Matsuoka M 《International journal of medical informatics》2004,73(3):311-316
To enhance medical cooperation between the hospitals and clinics around Osaka local area, the healthcare network system, named Osaka Community Healthcare Information System (OCHIS), was established with support of a supplementary budget from the Japanese government in fiscal year 2002. Although the system has been based on healthcare public key infrastructure (PKI), there remain security issues to be solved technically and operationally. An experimental study was conducted to elucidate the central and the local function in terms of a registration authority and a time stamp authority in contract with the Japanese Medical Information Systems Organization (MEDIS) in 2003. This paper describes the experimental design and the results of the study concerning message security. 相似文献
103.
分析47例骨髓穿刺干抽的临床和病理改变,干抽占同期1319例骨穿的3.6%。根据骨髓细胞的密度和间质纤维增殖的程度,把干抽的原因分为4类:高细胞伴间质细胞增多者19例(42.2%);间质细胞增多者14例(31.1%);高细胞者8例(17.8%)及低细胞者4例(8.9%)。主要疾病为:急性淋巴细胞白血病(25.5%),急性非淋巴细胞白血病(17.0%),慢性白血病(14.9%),骨髓转移瘤(10.6 相似文献
104.
目的探讨高眼压状态下青光眼手术方法的安全性和效果。方法对32例药物降压无效的青光眼患者进行青光眼手术,术后观察出血、滤过泡、前房、眼压及视力的变化。结果术后1月视力提高的21只眼(65.63%);保持不变的11只眼(34.38%);眼压术后≤21mmHg者28只眼(87.5%);用药物控制的4只眼(12.5%)。结论高眼压状态采取手术治疗是安全有效的。 相似文献
105.
Myung Ha Yoon Kyung Deok Park Hyung Gon Lee Woong Mo Kim Tae Hoon An Yeo Ok Kim Lan Ji Huang Cui Jin Hua 《Journal of Korean medical science》2008,23(6):1033-1038
The possible characteristics of spinal interaction between sildenafil (phosphodiesterase 5 inhibitor) and morphine on formalin-induced nociception in rats was examined. Then the role of the opioid receptor in the effect of sildenafil was further investigated. Catheters were inserted into the intrathecal space of male Sprague-Dawley rats. For induction of pain, 50 µL of 5% formalin solution was applied to the hind-paw. Isobolographic analysis was used for the evaluation of drug interaction between sildenafil and morphine. Furthermore, naloxone was intrathecally given to verify the involvement of the opioid receptor in the antinociception of sildenafil. Both sildenafil and morphine produced an antinociceptive effect during phase 1 and phase 2 in the formalin test. The isobolographic analysis revealed an additive interaction after intrathecal delivery of the sildenafil-morphine mixture in both phases. Intrathecal naloxone reversed the antinociception of sildenafil in both phases. These results suggest that sildenafil, morphine, and the mixture of the two drugs are effective against acute pain and facilitated pain state at the spinal level. Thus, the spinal combination of sildenafil with morphine may be useful in the management of the same state. Furthermore, the opioid receptor is contributable to the antinocieptive mechanism of sildenafil at the spinal level. 相似文献
106.
Coombes JS Powers SK Demirel HA Jessup J Vincent HK Hamilton KL Naito H Shanely RA Sen CK Packer L Ji LL 《Acta physiologica Scandinavica》2000,169(4):261-269
Reactive oxygen species (ROS) contribute significantly to myocardial ischaemia-reperfusion (I-R) injury. Recently the combination of the antioxidants vitamin E (VE) and alpha-lipoic acid (alpha-LA) has been reported to improve cardiac performance and reduce myocardial lipid peroxidation during in vitro I-R. The purpose of these experiments was to investigate the effects of VE and alpha-LA supplementation on cardiac performance, incidence of dysrhythmias and biochemical alterations during an in vivo myocardial I-R insult. Female Sprague-Dawley rats (4-months old) were assigned to one of the two dietary treatments: (1) control diet (CON) or (2) VE and alpha-LA supplementation (ANTIOXID). The CON diet was prepared to meet AIN-93M standards, which contains 75 IU VE kg-1 diet. The ANTIOXID diet contained 10 000 IU VE kg(-1) diet and 1.65 g alpha-LA kg(-1) diet. After the 14-week feeding period, significant differences (P<0.05) existed in mean myocardial VE levels between dietary groups. Animals in each experimental group were subjected to an in vivo I-R protocol which included 25 min of left anterior coronary artery occlusion followed by 10 min of reperfusion. No group differences (P>0.05) existed in cardiac performance (e.g. peak arterial pressure or ventricular work) or the incidence of ventricular dysrhythmias during the I-R protocol. Following I-R, two markers of lipid peroxidation were lower (P<0.05) in the ANTIOXID animals compared with CON. These data indicate that dietary supplementation of the antioxidants, VE and alpha-LA do not influence cardiac performance or the incidence of dysrhythmias but do decrease lipid peroxidation during in vivo I-R in young adult rats. 相似文献
107.
尺神经深支,骨间前神经旋前方肌支的应用解剖 总被引:2,自引:1,他引:2
尺神经深支向近侧无损伤分离后,可超越旋前方肌上缘以上26.58mm,此时宽1.80mm、厚1.00mm,可与宽1.35mm、厚0.89mm的旋前方肌支缝合。 相似文献
108.
目的 评价3 2 磷简易敷贴药膜治疗小儿皮肤血管瘤的效果 .方法 2 4 5 0例不同年龄的血管瘤小儿接受3 2 磷简易敷贴药膜治疗 ,治疗次数为 1~ 9次 ,平均 3.5次 ;每次间隔 2个月 ,按不同年龄给不同的照射量 ,以治疗时间换算 ,每次治疗剂量为 0 .92 5MBq/cm2 × ( 12~ 4 2 )h .结果 血管瘤和血管痣治愈率 71.7% ,部分治愈 2 2 .5 % ,总有效率 94 .2 % ,无效者 5 .8% .其中血管瘤效果明显优于血管痣 (p<0 .0 1) ,并且年龄越小效果越明显 (p<0 .0 1) .结论 3 2 磷简易敷贴药膜治疗小儿皮肤血管瘤是一种治疗简便、疗效确切的方法 ,尽早治疗效果更明显 相似文献
109.
壳聚糖醋酸溶液对凝血作用的研究 总被引:1,自引:0,他引:1
研究了不同脱乙酰度和不同分子量壳聚糖醋酸溶液的凝血作用。发现壳聚糖醋酸溶液使抗凝血液中红细胞发生了明显的聚集和变形。通过不同分子量和脱乙酰度壳聚糖的促红细胞聚集实验,证明了低脱乙酰度壳聚糖(60%~70%)使红细胞聚集效果更好,分子量在105~106范围内作用不十分明显。对血液的凝血酶时间(TT)、凝血酶原时间(PT)、活化部分促凝血酶原激酶时间(APTT)和纤维蛋白原浓度(FIB)的测定结果验证了壳聚糖醋酸溶液凝血机理不依赖于血小板和常规“瀑布”凝血机制。 相似文献
110.
目的探讨建立稳定大鼠减体积原位肝移植模型的方法。方法利用两袖套法连接肝下下腔静脉及门静脉,单线连续吻合肝上下腔静脉。共完成120例大鼠减体积原位肝移植模型。结果顺利完成模型建立,移植术后大鼠均能自由活动,进食活跃。其2d和7d存活率分别为85.8%和83.3%。结论利用改进的两袖套法,可以建立稳定的大鼠同种异体减体积原位肝脏移植模型。 相似文献