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71.

Purpose

To evaluate dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) for prediction and early monitoring of treatment in colorectal liver metastases.

Materials and methods

Ten patients were included. Baseline and follow-up DCE-MRI examinations were evaluated by whole tumour and selected ROI placements calculating Kep-values. Selective ROIs, concentric-like and hot spot, were drawn on early arterial phase images. Monitoring of treatment was performed comparing RECIST1.1 criteria with whole tumour and selected ROI placement. To evaluate treatment effect between responders and non-responders, independent samples t-test was used on Kep-values.

Results

In each patient largest lesion was evaluated totalling 10 target lesions. At baseline, for whole tumour ROI placements mean Kep-values in responders were significantly higher than mean Kep-values in non-responders (t = 7.481, p < 0.001). Selective ROI placement comparison of mean Kep-values at baseline and after 6 weeks of treatment (first follow-up measurement) showed significant decrease in responding patients (t = 4.706, p = 0.003) whereas increase in Kep-values in non-responding patients was not statistically significant.

Conclusion

This preliminary study shows that baseline Kep for whole tumour ROI is a predictor for treatment outcome. Decrease of Kep using selective ROIs allows early identification of response after 6 weeks of treatment.  相似文献   
72.
本文收集1980年1月至1995年12月间治疗手热辊筒挤压伤72例,均使用皮瓣修复.下腹部皮瓣26块,髂腰部皮瓣30块,前臂岛状皮瓣3块,侧胸部皮管11个.文章讨论了手热辊筒挤压伤的特点及分类,手术方法的选择,髂腰部皮瓣是修复手热辊筒挤压伤最理想的供瓣区.  相似文献   
73.
黄芪皂苷甲的镇痛、镇静作用   总被引:3,自引:0,他引:3  
本文证实给小鼠黄芪皂苷甲后出现镇痛作用,其镇痛作用较度冷丁弱而短。根据对小鼠腹腔注射醋酸产生扭体反应抑制率测得静脉注射黄芪皂苷甲的ED50为47.8±3.4mg/kg;由热板法测得的ED50为25.4±1.5mg/kg。黄芪皂苷甲也能明显延长硫喷妥钠所致小鼠的麻醉时间。此外,黄芪皂苷甲还能使豚鼠离体回肠张力下降。  相似文献   
74.
Summary Current physiological criteria for limiting work in hot conditions are frequently based on responses to mainly dynamic work (eg treadmill walking). Their applicability to industrial situations containing mixed static and dynamic work is questioned, since the physiological responses to static work are different from those of dynamic work. Each of eight subjects attempted a one hour uphill treadmill walk (mainly dynamic work), and an uphill treadmill walk whilst intermittently carrying a 20 kg weight in the arms (mixed static and dynamic work). The external work rates in the two conditions were equal, effected by lowering the treadmill gradient in the loaded condition. Experiments were conducted in a hot climate (33‡ C dry bulb, 25‡ C wet bulb). Oxygen consumption, minute ventilation, sweat rate and rated perceived exertion were all significantly higher (p<0.001) for the mixed static and dynamic work than for the dynamic work. This was also the case for heart rate and forearm skin temperature (p<0.01), and for auditory canal temperature (p<0.05). There was no significant difference between the two types of work for mean skin temperature, calf skin temperature and chest skin temperature. These results show that for the same external work, physiological strain and perceived exertion are greater for mixed static and dynamic work (carrying a load in the arms) than for mainly dynamic work (walking on a treadmill). They suggest that it is not appropriate to make direct comparisons of laboratory studies based on dynamic work, with practical situations containing mixed static and dynamic work in the heat.  相似文献   
75.
Nerve growth factor (NGF) plays a role in mechanisms of inflammation and hyperalgesia in adult animals. We sought to determine if NGF depletion produced by autoimmunization of adult rats altered their thermal sensitivity to an acute noxious thermal stimulus. Anti-NGF IgG was not detected in the cerebrospinal fluid of any tested samples. Only those rats with the highest anti-NGF serum titers showed significant (P<0.05) thermal hypoalgesia measured using the hot plate test (52°C): the mean (±S.D.) hind paw lick latency of rats in the high anti-NGF titer group was 18.0±4.6 s compared to means of 10.8±4.3 s, 9.2±2.6 s and 10.1±3.0 s in the medium, low and control groups, respectively. Thus, NGF depletion by autoimmunization is a useful model for investigating the role of NGF in behavioral responses of adult rats to noxious stimuli, providing high titers of antibody are present.  相似文献   
76.
BACKGROUND: Combined use of blue dye and radiocolloid is considered to be useful for sentinel lymph node (SLN) biopsy of breast cancer. Whether both techniques together is superior to either alone was analyzed. PATIENTS AND METHODS: A consecutive series of 308 cases of breast cancer who underwent SLN biopsy using the combination technique was used. The frequency of a blue node or hot node was analyzed in all cases and only node-positive cases. Furthermore, the frequency of a blue node and hot node together, or either alone, and the highest radiocount of the SLNs in each case were examined for correlation with 8 clinicopathologic features. Three types of SLN containing both blue dye and radioactivity (blue-hot node), blue dye alone (blue-only node) and radioactivity alone (hot-only node), and the SLN radiocounts were analyzed for correlation with metastatic tumor. RESULTS: Of 308 cases, a blue node was present in 298 (97%), a hot node in 295 (96%), and either a blue or hot node in 306 (99%). The presence of a blue node or hot node was similarly affected by previous surgical biopsy and body mass index (BMI), and the presence of a hot node was also affected by age and tumor location. However, the presence of either a blue node or hot node was not affected by any of these characteristics. Of 77 node-positive cases, 8 (10%), 15 (19%) and 6 (8%) were considered to be node-negative based on blue node, hot node and either blue node or hot node positivity, respectively. The frequency of positivity for SLN metastasis decreased in order from blue-hot, blue-only to hot-only nodes. Of 62 cases with metastatic hot nodes, six (10%) were negative when the hottest node was examined, but the second-hottest node was positive. CONCLUSIONS: The added value of the presence of blue node or hot node was confirmed in the SLN biopsy using the combination technique, which suggests that all blue nodes and hot nodes need to be harvested.  相似文献   
77.
Rationale Clinical observations have shown that pain sensitivity is altered in some schizophrenic patients.Objectives To study alterations in pain sensitivity, the ketamine model in schizophrenia research was employed.Materials and methods Rats were subchronically injected with the dissociative anaesthetic ketamine (Ket, ten injections of 30 mg/kg, one injection per day over a period of 10 days). Two weeks after treatment completion, the animals’ pain sensitivity was assayed in the hot plate test and they were subjected to electrical stimulation of the tail root. In addition, the effect of morphine was studied.Results In group-housed animals, there was no difference between Ket-injected animals and control rats as measured in both nociceptive tests. In singly housed Ket-injected rats, pain threshold was increased in the electrical stimulation test. This suggests that stress due to single housing might be essential for modifications of pain sensitivity. Moreover, the antinociceptive effect of morphine was modified after single housing. Interestingly, the effect of morphine on locomotor activity was similar in both groups. In group-housed rats, μ receptor binding was unchanged in the frontal cortex, whereas Ket-injected animals had decreased levels in the hippocampus. In singly housed animals, μ receptor binding in Ket-injected rats increased in the frontal cortex and decreased in the hippocampus. 35S-GTPγ-S binding increased in the frontal cortex in both singly housed groups, but remained unchanged in the hippocampus.Conclusions The data suggest that the ketamine model might be useful for studying altered pain sensitivity in schizophrenia. Moreover, the data suggest that modifications in μ opioid receptor binding contribute to this phenomenon.  相似文献   
78.
M E Paterson 《Maturitas》1982,4(2):83-94
A randomised, double-blind, cross-over study into the effect of graded sequential mestranol and norethisterone on climacteric symptoms was performed. The study group consisted of 23 post-menopausal women who had previously undergone hysterectomy. Active therapy resulted in a significant reduction in hot flushes and night sweats. There was a slight improvement in insomnia, lack of energy and confidence but the other symptoms were not significantly altered. A small placebo effect was noted but this was only significant 1 mth after active treatment had been discontinued in the group of women receiving placebo second. Active treatment also resulted in a significant reduction in serum sodium, calcium, albumin, alkaline phosphatase and cholesterol, and increase in serum triglycerides, but no alteration in the other biochemical parameters, weight or blood pressure.  相似文献   
79.
吻合血管的脐旁皮瓣联合分叶带蒂皮瓣修复手部热压伤   总被引:1,自引:0,他引:1  
目的探讨吻合血管的脐旁皮瓣联合分叶带蒂皮瓣修复手背及指背热压伤的方法。方法切取脐旁皮瓣,近端皮瓣血管蒂与手部鼻烟壶部桡动脉深支及其伴行静脉吻合,皮瓣远端分成四叶瓣并与腹部带蒂相连,以保证指背远侧皮瓣血供。一期分指,重建指蹼,修复手背热压伤。结果皮瓣完全成活,质地柔软,色泽均匀,随访5个月功能及外形均比较满意。结论吻合血管的脐旁皮瓣联合分叶带蒂皮瓣修复手背及指背热压伤,可一期分指,减少了手术次数和瘢痕形成,有利于手部功能及外形的恢复。  相似文献   
80.
目的 探讨热休克蛋白47(HSP47)在肾小管间质纤维化中的作用及其可能机制。 方法 常规培养人肾小管上皮细胞(HK-2),分为对照组、转化生长因子β1(TGF-β1)组、HSP47-siRNA组。RT-PCR检测HSP47、胶原Ⅳ、纤连蛋白(FN)、组织型纤溶酶原激活物抑制剂1(PAI-1)的mRNA表达。Western印迹检测HSP47、胶原Ⅳ、FN蛋白表达。ELISA检测PAI-1的蛋白量。 结果 HK-2细胞有HSP47表达。不同浓度TGF-β1(0、2.5、5、10 μg/L)干预不同时间(12、24、48 h)时,HSP47基因和蛋白表达呈浓度和时间依赖性增高,10 μg/L TGF-β1干预HK-2细胞48 h时,HSP47 mRNA和蛋白表达最强。不同浓度 TGF-β1(0、5、10 μg/L)干预HK-2不同时间(12、24、48 h)时,胶原Ⅳ、FN 、PAI-1 mRNA和蛋白表达亦呈浓度和时间依赖性增高,10 μg/L TGF-β1作用48 h时,3者mRNA和蛋白表达最强。与TGF-β1组比较,HSP47-siRNA组的HSP47、胶原Ⅳ、FN、PAI-1 mRNA和蛋白表达都明显下调。 结论 HSP47可促进肾小管间质纤维化,其机制可能与上调胶原Ⅳ、FN、PAI-1表达有关。  相似文献   
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