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81.
目的:探讨微卫星不稳定性在尖锐湿疣及其癌变中的作用及意义。方法:采用聚合酶链-单链构象多态性分析(PCR-SSCP)检测28例尖锐湿疣皮损中的微卫星DNA改变。结果:28例尖锐湿疣皮损中8例存在微卫星不稳定性。而且其主要出现在尖锐湿疣癌变中,未发现杂合性丢失。结论:尖锐湿疣及其癌变与微卫星不稳定性有关,临床上通过对尖锐湿疣患者微卫星不稳定性的检测,有可能对尖锐湿疣癌变作出可能性预测及早期诊断,为发现癌变高危人群提供新的依据。  相似文献   
82.
The aim of this study is to investigate the antitumor activity of Plantago major L. extract in Ehrlich ascites tumor (EAT) bearing Balb/C mice in vivo. Thirty male Balb/C mice were divided into 5 groups: 3 treatment groups and 2 control groups (6 per group). Treatment groups and the negative control group were injected with EAT (1 x 10(6) cells) intraperitoneally to develop ascites tumor. P. major L. extract (1%, 2% and 3% concentration extracts, 0.1 ml/day/mouse) were given p.o. for 10 alternate days. The control group was treated with 0.9% NaCl solution (0.1 ml/day/mouse). The changes of body weight in animals were recorded. On the 11th day, all of the mice were sacrified and their tissues were stained with haematoxylen and eosin for pathological studies. Body weights of in 3 treatment groups and the negative control group were elevated because of tumor burden. The maximal weight gain was recorded in the negative control group and the minimal weight gain was recorded in Group I. Pathological studies showed that P. major L. extract (especially 1% concentration) has inhibitive effect on EAT. P. major has an inhibitory effect on EAT in a dose dependent manner.  相似文献   
83.
Dichlorvos is an organophosphorus insecticide that is used worldwide for pest control in agriculture and household use. Vitamins C and E are potential antioxidants protecting cells from oxidative stress. Vitamin C + vitamin E, dichlorvos, a combination of vitamin C + vitamin E + dichlorvos, or corn oil (control) were given to rats via oral gavage for 7 weeks. Body and testis weights, sperm parameters, hormone levels, histo- and cytopathological changes in testes were investigated at the end of 24 h and the 4th and 7th weeks comparatively with the control group. Body and testis weights, sperm morphology, FSH, LH, and testosterone levels were decreased significantly at the end of 4th and 7th weeks in the dichlorvos- and vitamins + dichlorvos-treated groups. A statistically significant decline in sperm motility and testosterone levels occurred by the end of 7th week in the dichlorvos- and vitamins + dichlorvos-treated groups. Light and electron microscopy revealed necrosis, edema and cellular damage in testicular tissues of the dichlorvos- and vitamins + dichlorvos-treated rats at the end of 4th and 7th weeks. In conclusion, dichlorvos caused subacute and subchronic reproductive toxicity, but vitamins did not confer protection.  相似文献   
84.
Future medical CT scanners and today's micro CT scanners demand cone-beam reconstruction algorithms that are capable of reconstructing data acquired from a tilted spiral trajectory where the vector of rotation is not necessarily parallel to the vector of table increment. For the medical CT scanner this case of nonparallel object motion is met for nonzero gantry tilt: the table moves into a direction that is not perpendicular to the plane of rotation. Since this is not a special application of medical CT but rather a daily routine in head exams, there is a strong need for corresponding reconstruction algorithms. In contrast to medical CT, where the special case of nonperpendicular motion is used on purpose, micro CT scanners cannot avoid aberrations of the rotational axis and the table increment vector due to alignment problems. Especially for those micro CT scanners that have the lifting stage mounted on the rotation table (in contrast to setups where the lifting stage holds the rotation table), this kind of misalignment is equivalent to a gantry tilt. We therefore generalize the advanced single-slice rebinning algorithm (ASSR), which is considered a very promising approach for medical cone-beam reconstruction due to its high image quality and its high reconstruction speed [Med. Phys. 27, 754-772 (2000)], to the case of tilted gantries. We evaluate this extended ASSR approach (which we will denote as ASSR+, for convenience) in comparison to the original ASSR algorithm using simulated phantom data for reconstruction. For the case of nonparallel object motion ASSR+ shows significant improvements over ASSR, however, its computational complexity is slightly increased due to the broken symmetry of the spiral trajectory.  相似文献   
85.
SUMMARY Many previous studies of reported patient accidents in hospital used the accident report forms as the only data source, without questioning their reliability and despite 80% of the accidents being unwitnessed. This paper reports on three studies using data from patient interviews, staff questionnaires, medical and nursing notes and the accident report forms. The studies confirm that falls amongst elderly patients are the most common type of patient accident. However, patients' and staff's versions of the event often differed widely. Accident reports are stated to be required for legal purposes, but they were often incomplete and unreliable. Patient accidents and safety are too important to remain marginalised to mere compliance with out-of-date regulations. A new, ‘slim-line‘, more accurate but less time-consuming patient accident reporting system should be developed, for which improvement in patient safety is the main aim and legal considerations the secondary aim.  相似文献   
86.
癫痫患者全夜自然睡眠结构的研究   总被引:1,自引:0,他引:1  
目的 观察癫痫患者发作间期全夜自然睡眠结构特点 ,并评价其与正常对照组睡眠结构的差异 ;评价发作类型、用药情况及是否记录到发作间电发放对睡眠结构的影响。方法 对 2 0名癫痫患者及 11名对照进行全夜自然睡眠多导监测 ,并结合患者的发作类型、是否记录到发作间电发放 (IIDs)及服用 AEDs的情况进行分组统计分析 ,评价各组患者与正常对照间各睡眠参数的差异。结果 癫痫患者组 ,记录到 IIDs组 ,及该组患者中部分性发作者和未服 AEDs者均较正常对照 TRT、RL 显著延长 (P<0 .0 5)。记录到 IIDs的患者睡眠效率显著下降 (P≤0 .0 5) ,其中部分性发作者入睡后觉醒次数较全身性发作者显著增多 (P<0 .0 5)。部分性发作者较全身性发作者NREM睡眠期转换次数有增高的趋势。不同用药癫痫患者睡眠脑电图较正常对照组睡眠破碎性增加。结论 癫痫患者与正常对照比较 RL延长 ;睡眠破碎性增加 ;记录到 IIDs的患者睡眠效率降低 ;部分性发作患者较全身性发作患者有 NREM期转换次数频繁的趋势 ;记录到 IIDs患者中服用 AEDs的情况对其睡眠结构无显著影响。  相似文献   
87.
Castleman's disease is a lymphoproliferative disorder of uncertain cause characterized by a distinctive pattern of hypervascular lymphoid hyperplasia. Computed tomography and MRI can be used to define the extent of disease. The latter may be used to detect curvilinear hypointensities within the abnormal node. Symmetrical involvement of nasopharyngeal and parapharyngeal regions in our case without disease elsewhere is considered to be an unusual presentation.  相似文献   
88.
The residues of persistent organochlorinated pollutants (POPs), namely polychlorinated biphenyls (PCBs) and organochlorine pesticides (OCPs) (HCHs, CHLs, HCCPs, DDTs, and dicofol congeners) were investigated in the hair and muscle of road-killed Erinaceus roumanicus and E. concolor in Turkey. Mean residue levels were as follows: in hair, PCBs?=?7.43?±?4.88 ng/g and OCPs?=?9.21?±?1.27 ng/g; in muscle, PCBs?=?30.73?±?2.51 ng/g and OCPs?=?145.04?±?16.59 ng/g. There was no significant difference between species and sex, while there was significant difference between habitats and regions in terms of either total PCB and OCP levels, or POP levels (p?<?0.05). Age was a determinative factor for the bio-accumulation of POPs. The contaminant levels were high in the species, sample areas, and habitats. The data also showed that tissues of hedgehogs are suitable for monitoring and evaluating the bioaccumulation of POP levels in Turkey.  相似文献   
89.
90.
[目的]观察胃底折叠术治疗胃食管反流病对高血压的影响。[方法]回顾性分析2011-06—2012-08期间20例行腹腔镜胃底折叠术的胃食管反流病合并高血压患者的临床资料,依照反流病诊断问卷在手术前和手术后进行反流症状评分。[结果]20例均成功实施腹腔镜手术并于术后第12个月随访。反流总积分(Sc)由术前20.0±9.5降至术后0.5±0.9(P0.05),术后收缩压下降了(11.0±12.0)mm Hg(1mmHg=0.133kPa),舒张压下降了(9.0±11.5)mm Hg(均P0.05)。术后随访12个月11例血压恢复正常,停药时间均在9个月以上;2例减少2种降压药,1例减少1种降压药;6例无效,仍用术前降压药物。[结论]胃食管反流病与部分高血压密切相关,腹腔镜胃底折叠术治疗胃食管反流病合并高血压安全、有效。  相似文献   
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