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991.
992.
The effects of thermochemotherapy using cyclophosphamide plus hyperthermia on the malignant pleural mesothelioma in vivo 总被引:2,自引:0,他引:2
The human malignant pleural mesothelioma is related to the use of asbestos in the majority of cases. Though the use of asbestos has been prohibited since the 1990s, the incidence of pleural mesothelioma is still increasing because of a latency period of at least 20 years. This study investigated the benefit of single therapy with cyclophosphamide or hyperthermia or the combination of both on cells of a human pleural mesothelioma cell line, xenotransplanted subcutaneously in the paw of mice. A CONTROL group received the same volume of physiological saline. The oxygenation of tumours was measured, tumour growth was followed over 3 weeks, immunohistochemical studies and a light and electron microscopic evaluation were performed. Chemotherapy or hyperthermia alone was only temporarily effective. The greatest benefit was achieved using combined thermochemotherapy consisting of cyclophosphamide plus hyperthermia: 50% of this group had partial remissions, and 67% responded to this therapy. After 3 weeks tumours grew again. Superior effects could be achieved by performing additional cycles of chemotherapy or adding another drug or radiation for instance. This study shows promising results in the treatment of malignant pleural mesothelioma. 相似文献
993.
Objective: To present the case of a 17-year-old male soccer goalkeeper who sustained maxillofacial fractures and dental trauma after being struck in the face by an opponent's knee.Background: Because of the nature of the sport and a lack of protective headgear, soccer players are at risk for sustaining maxillofacial trauma. Facial injuries can complicate the routine management of on-field medical emergencies often encountered by certified athletic trainers. The appropriate management of maxillofacial trauma on the playing field may help to reduce both the immediate and long-term morbidity and mortality associated with these injuries.Differential Diagnosis: Lacerated superior labial artery, lacerated upper lip, dental fractures, maxillofacial fractures, orbital blowout fracture, closed head injury, cervical spine injury, cerebrovascular accident.Treatment: The athlete received immediate on-field medical care and was subsequently transported to the hospital, where diagnostic testing was performed and further treatment was provided. Hospital inpatient management included dental and plastic surgery. After discharge from the hospital, the athlete underwent several additional dental procedures, including gingival surgery and nonsurgical endodontic treatments. The fractures were followed closely to assure that adequate healing had occurred. The athlete did not return to soccer.Uniqueness: Certified athletic trainers need to be prepared for on-field medical emergencies. Bleeding associated with maxillofacial trauma can complicate basic medical interventions such as airway maintenance. Inappropriate on-field management may result in unnecessary morbidity and mortality for the injured athlete. Therefore, immediate recognition of the severity of the injury is needed in order to institute appropriate airway-management strategies.Conclusions: It is sometimes necessary to consider nonstandard methods of airway management in order to first address heavy bleeding that may be associated with facial trauma. Achieving hemostasis is essential in order to prevent potentially life-threatening complications related to hemorrhage, such as airway obstruction and hypovolemic shock. 相似文献
994.
本文综述一类基于 EEG信号 AR谱和 AR模型参数分析的中枢神经系统损伤检测方法 ,包括主控频率法、AR谱距离法和 Itakura距离测度法等。这类方法根据 EEG信号的 AR模型建立分析 EEG信号状态和变化的测度 ,并利用其检测中枢神经系统在缺氧窒息实验过程中可能存在的损伤并预测最终结果。实验和数据分析的结果表明 ,这类方法在实验各个阶段的检测结果与采用医学方法进行综合评价的 NDS结果一致 ,具有较高的可靠性。 相似文献
995.
Objectives: To look for possible association between past history of ovulation induction and age at menopause. Design: Women attending our postmenopausal outpatient clinic were asked to fill questionnaires with demographic data, obstetrical history (including treatment for infertility), and medical details related to menopause. Patients: The study group (n=31) consisted of women with a history of ovulation induction, and a control group (n=200) included women who did not experience such intervention. Results: The age at the final menstrual bleeding was 46.4±5 in the study group, and 50±4 for the control group (P<0.001). This difference was most prominent for women who had induction of ovulation prior to age 35 years: they entered menopause at age 43.8±5 years. Smoking had a weak effect on the age at menopause (48.5±4 for current, vs. 49.9±4 for non- or past-smokers; P<0.03). Conclusions: This retrospective and preliminary study raises the question whether hormonal manipulations and ovarian over-stimulation during fertility treatments could be a risk factor for premature menopause. 相似文献
996.
Sheth BR Shimojo S 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》2002,143(2):181-190
Pointing movements made with a hidden cursor from the center of gaze to a stationary, visible target overshot the actual target location. The systematic error decreased when the final cursor location from the previous trial was shown, which likely led to the creation of an internal sensorimotor model of movement. However, the putative model had a short memory, and could not substitute for on-line visuomotor feedback on subsequent trials. Contrary to common belief, the effect of a lack of visuomotor feedback was seen even in the early acceleration stage of the movement trajectory. Unchecked in the absence of visual monitoring, the acceleration stage of the movement lasted longer, as was evidenced by the significantly larger value of the peak cursor speed. Moreover, the speed peaked much later in the course of the movement. Speed declined more rapidly thereafter. Consequently, the delayed deceleration stage lasted far less than the acceleration stage. In the absence of visual feedback, the shift rightward in time of the peak speed position (PSP) in relation to total movement duration and other changes in the trajectory imply that visual feedback must play a significant role in determining when acceleration ceases (d V/d t=0), and argue against the traditional notion that visuomotor feedback is unavailable until the later stages of movement. Moreover, our data suggest that non-visual modalities, e.g., proprioception, may be too slow to make up for the absence of vision. 相似文献
997.
目的 建立一个正常血钾型周期性麻痹(normokalemic periodic paralysis,normoKPP)R675Q新突变的细胞模型并对其通道电流进行初步研究.方法 用编码野生型人骨骼肌钠离子通道a亚单位基因(skeletal muscle Na channel type 4 alpha subunit gene,SCN4A)的cDNA为模板,PCR技术定点突变后磷酸钙沉淀法瞬时转染突变质粒至293细胞,逆转录PCR和Western印迹验证目的 基因和蛋白的表达;膜片钳技术全细胞记录野牛和突变型钠通道电流.结果 突变经测序得以证实;转染后24 h和48h,突变通道的基因及蛋白表达量显著增高;相同的测试电压下R675Q钠通道相对电流在到达峰值前小于野生型钠通道,到达峰值后大于野生型钠通道;R675Q和野生型钠通道均在0 mV测试电压刺激下到达峰值.结论 成功建立了正常血钾型周期性麻痹R675Q新突变的细胞模型;R675Q突变同时提高了通道的激活和失活,其所在的S4区域可能和患者发作性力弱的症状密切相关. 相似文献
998.
Glenn R. Farley Steven M. Barlow Ronald Netsell James V. Chmelka 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》1992,89(2):333-340
Summary Attempts to understand the neural mechanisms underlying mammalian vocal behaviors, including speech, require study of the neural activity and anatomy of vocalization-controlling brain structures. Such studies necessitate the application of invasive neurobiological techniques in animal models. In the current study, cats are used in the development of an animal model of vocal tract control. The animals are instrumentally conditioned to vocalize for food reward. Acquisition of this task can occur within a few minutes, although additional training generally is required to solidly establish the behavior and to train subjects to produce consistently high rates of vocalization for prolonged periods of time. Following training, animals can generally sustain a rate of two calls per minute for a period of over two hours. Optimal task performance is partly dependent on motivation level. Although there is considerable variation between animals, the vocalizations produced have an average duration of 600 ms and a fundamental frequency of around 500 Hz. In addition, during a typical vocalization, there are dynamic variations of about 150 Hz for fundamental frequency and 17 dB for sound intensity. These variations provide opportunities for relating neural and muscular activity to different aspects of the vocal behavior they control. Based on a number of considerations, the model and techniques discussed here probably are most applicable to studying the neurobiology of sub-cortical nuclei subserving vocal control. Similar mechanisms might well be present in other species, including humans. Thus, data obtained from study of this model may be applicable to understanding the processes underlying vocal tract control during human speech. 相似文献
999.
Phenotypic characterization and analysis of allogeneic T cell responses in ZAP-70 dominant negative transgenic mice 总被引:1,自引:0,他引:1 下载免费PDF全文
R P GLADUE M ALLEN A CUNNINGHAM J GARDNER A M LAQUERRE P A CONNELLY A S SHAW J MCNEISH 《Clinical and experimental immunology》1997,110(3):397-402
Antigen stimulation of T cells results in a series of biochemical events including the interaction of both SH2 domains of ZAP-70 with phosphorylated ITAMS on the T cell receptor. In order to study the physiological relevance of decreasing native ZAP-70–SH2 interaction in vivo, we generated transgenic mice expressing a T cell-specific, dominant negative form of ZAP-70 consisting of only the tandem SH2 domains (ZAP-NC). Phenotypically, these animals had a comparable distribution of lymphocyte subsets in the thymus and spleen compared with the wild-type (WT) controls. However, examination of peripheral blood revealed a slow but progressive decrease in the number of lymphocytes, particularly CD4+ cells, with age (17% reduction by 3 months, 58% reduction by 6 months). Allogeneic responses were then evaluated in vitro as well as in vivo using a subcutaneous sponge matrix implant. Although spleen cells cultured for 4 days in vitro with alloantigen developed normal functional responses, allogeneic responses generated in vivo within a subcutaneous sponge matrix were impaired. This was characterized by a depression in cytotoxic T lymphocyte (CTL) activity, a 82% reduction in the frequency of helper T cells, and a 78% reduction in the capacity of sponge-infiltrating lymphocytes to produce IL-2 in response to secondary antigen stimulation. These results indicate that although overt lymphocyte development and in vitro function were unremarkable, expression of a truncated ZAP-70 affected the in vivo survival of peripheral lymphocytes and altered the in vivo generation of functional activity to alloantigen. 相似文献
1000.
材料参数与镍钛形状记忆合金的本构关系 总被引:1,自引:0,他引:1
在Tanaka模型基础上,我们讨论了形状记忆合金热力学特性的本构关系。特别注意了桓温拉伸过程和强迫回复过程。本构方程的材料参数,即弹性模量D,变化张量Ω,热力弹性张量均以镍钛合金实验测试值来确定。在不同的应力-应变-温度关系试验中发现D和Ω与温度之间有很强的相关性。 相似文献