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91.
To assess the effect of stimulus correlated motion on the appearance of functional magnetic resonance images, conventional visual and motor protocols were each performed by four normal volunteers and an image co-registration technique was used to retrospectively monitor subject motion. In three studies synthetic data sets were constructed from single baseline images using the positional information obtained from the co-registration procedure. Cumulative difference images were then created from both the synthetic and functional image sets. Stimulus correlated motion was detected in all eight studies and the synthetic cumulative difference images showed striking similarities to the equivalent functional images in each case.  相似文献   
92.
BACKGROUND/PURPOSE: In the geriatric population, the reliability of pure-tone threshold (PTT) is sometimes poorer than that in young adults because of various reasons. This study assessed the relationship between Mandarin speech reception thresholds (SRTs) and PTTs in the aged and developed SRT as a measure for corroborating PTT. METHODS: This prospective study enrolled 46 consecutive subjects over 60 years of age. The results of SRT and PTT were collected from one ear randomly selected from each subject. Simple linear and multiple regressions were used to determine the correlation and linear regression coefficients between SRTs and PTTs at various frequencies. RESULTS: In the simple regression analysis, the correlation coefficient was highest at 1000 Hz (r = 0.949) and 500 Hz (r = 0.922), followed by 250 Hz (r = 0.850) and 2000 Hz (r = 0.792). In the multiple regression model with SRT as the dependent variable and PTTs as predictor variables, the resultant multiple correlation coefficient R was 0.967, while R2 was 0.936. In this model, PTTs at the frequencies of 500 Hz and 1000 Hz contributed significantly to the variance in SRTs with p values of 0.029 and < 0.001, respectively. These results demonstrated that the Mandarin SRT is strongly associated with PTTs at the frequencies of 500 Hz and 1000 Hz. CONCLUSION: This study established the agreement between Mandarin SRTs and PTTs in the low tone area of speech frequencies in the geriatric population. In clinical settings, SRT test can be rapidly and easily performed and is relatively inexpensive. It is a vital indicator of the accuracy of PTT measurement.  相似文献   
93.
目的 探讨产程中改变产妇体位以矫正胎位的临床效果。方法 选择潜伏期经内诊或B超确诊为枕后位的初产妇170例,随机分成研究组和对照组,各85例。研究组在产程中指导产妇取侧俯卧位,对照组孕妇任意体位。结果 研究组72例(84.71%)胎儿从枕后位转至枕前位经阴道娩出。剖宫产13例,占15.29%,对照组经阴道娩出仅28例,22.94%,剖宫产57例,67.06%。两组比较,P<0.01),差异有非常显著性。两组产程比较,P<0.01,差异有极显著性。结论 在产程中指导产妇取胎儿脊柱侧行同侧侧俯卧位矫正胎头枕后位可降低难产发生率及剖宫产率,有助于提高分娩质量。  相似文献   
94.
BACKGROUND: There is a lack of information from Canadian hospitals on the role of hospital characteristics such as procedure volume and teaching status on the survival of patients who undergo major cancer resection. Therefore, we chose to study these relationships using data from patients treated in Ontario hospitals. METHODS: We used the Ontario Cancer Registry from calendar years 1990-2000 to obtain data on patients who underwent surgery for breast, colon, lung or esophageal cancer or who underwent major liver surgery related to a cancer diagnosis between 1990 and 1995 in order to assess the influence of volume of procedures and teaching status of hospitals on in-hospital death rate and long-term survival. For each disease site and before observing patient outcomes data, volume cut-off points were selected to create volume groups with similar numbers of patients. Teaching hospitals were those directly affiliated with a medical school. Logistic regression and proportional hazards models were used to consider the clustering of data at the hospital level and to assess operative death and long-term survival. We also used 4 measures to gauge the degree of procedure regionalization across the province including (1) the number of hospitals performing a procedure; (2) the percentage of patients treated in teaching hospitals; (3) the percentage of rural patients treated in higher volume procedure hospitals; and (4) median distances travelled by patients to receive care. RESULTS: The number of patients in our cohorts who underwent resection of the breast, colon, lung, esophagus or liver was 14 346, 8398, 2698, 629 and 362, respectively. Surgery in a high-volume versus a low-volume hospital did not have a statistically significant influence on the odds of operative death for patients who underwent colon, liver, lung or esophageal cancer resection. The risk of long-term death was increased in low-volume versus high-volume hospitals for patients who underwent resection of the breast (hazard ratio [HR] 1.2, 95% confidence interval [95% CI] 1.0-1.4, p < 0.05), lung (HR 1.3, 95% CI 1.1-1.6, p < 0.01) and liver (HR 1.7, 95% CI 1.0-2.7, p = 0.04). There were no significant differences in the odds of operative (in-hospital) death or risk of long-term death among patients treated in teaching compared with nonteaching hospitals. There was more regionalization of liver, lung and esophageal operations versus breast and colon operations. CONCLUSIONS: Increased hospital procedure volume correlated with improved longterm survival for patients in Ontario who underwent some, but not all, cancer resections, whereas hospital teaching status had no significant impact on patient outcomes. Across the province, further regionalization of care may help improve the quality of some cancer procedures.  相似文献   
95.
应用全血血小板聚集仪阻抗法对34例白血病患者的血小板聚集和 ATP 释放进行了同步测定。结果表明:白血病患者的血小板聚集和 ATP 释放明显低于正常。提示白血病患者不仅有血小板投量减少,亦存在其聚集及释放功能的障碍。  相似文献   
96.
本实验采用随机引物法标记探针DNA.探针DNA加热变性成单链,以单链DNA为模板,六聚脱氧核苷酸为引物,在DNA多聚酶I大片段的作用下进行放射性标记.标记探针的比放射性达10~8cpm/μg DNA以上.放射性底物的掺入率为60%.用该方法标记的人高度重复顺序探针,可以检出微微克水平的阳性分子.与人HeLa S_3细胞DNA转化的小鼠LTK~+细胞DNA打点杂交呈阳性,与未经转化的小鼠LTK~-细胞DNA杂交为阴性,证明小鼠转化细胞中存在HeLa细胞DNA,DNA转化是成功的.  相似文献   
97.
目的探讨本地区脑梗塞患者的血清叶酸、维生素B12(VitB12)与同型半胱氨酸(Hcy)水平及血脂水平的关系。方法应用全自动化学发光免疫法测定115例脑梗塞患者血清叶酸、维生素B12水平,采用荧光定量分析法测定血清同型半胱氨酸水平,采用免疫比浊法测定血脂水平。结果脑梗塞患者血清叶酸水平明显低于对照组(P〈0.001),血清Hcy及甘油三酯(TG)水平明显高于对照组(P〈0.01),而维生素B12及其余所测血脂指标与健康对照组无显著差异(P〉0.05)。结论即时监测血清叶酸、Hcy及TG水平,适当补充叶酸,可早期预防和及时治疗脑血管疾病,降低脑梗塞的发生率及复发率。  相似文献   
98.
Conventional follicle harvesting techniques for hair transplantation are limited by the available scalp donor hair. The development of an innovative technique of microsurgical single follicular unit extraction has made it possible to exploit body hair grafts for scalp transplantation. This case study reports on 18 months of follow-up on a patient with extensive scalp scarring who underwent a transplantation procedure using donor chest hair. The photographically documented results show a change in the length of the chest hair measuring an average of 4 cm at transplant to 15 cm by 18 months post-transplant. The transplanted chest grafts provided an excellent cosmetic result for hair replacement.  相似文献   
99.
红外热像图在神经外科疾病中应用价值的评价   总被引:1,自引:0,他引:1  
目的 评价红外热像图在神经外科疾病中应用的价值。方法 应用红外热像图对39例脊髓损伤患者进行躯体温度监测,对31例颅内肿瘤、76例脑梗死、2480例头痛、21例头面部血管瘤进行头部温度监测。结果 红外热像图监测脊髓损伤39例,测出脊髓损伤平面上下无温差14例,平面以下温度增高1-3℃ 13例,下降1-3℃ 12例。经大网膜脊髓移植手术13例,术前脊髓损伤平面以下34℃,术后1个月复查皮肤温度,上升至35℃并伴有麻胀和皮肤湿润感7例,皮肤温度下降0.6℃者6例。热像图可显示血管性头痛颞部高温区,眶上神经痛同侧前额部皮肤低温区,枕大神经痛同侧枕颈部热区;热像图可显示梗死侧有低温区;显示颅内肿瘤颈外血管供血情况;基本上能反映头面部血管瘤血管侵及范围。结论 红外热像图在神经外科有其独特的价值,本技术具有无创、可重复、价廉和检查的非接触性等优点,反映组织代谢活跃状态与程度,是CT等形态学诊断方法的补充,在医学科学的研究和临床应用中具有很大的潜力。  相似文献   
100.
Background Significant tumor downstaging has been achieved in patients with localized gastric or gastroesophageal adenocarcinoma by induction chemotherapy and preoperative chemoradiotherapy (CTX–CTXRT). However, the influence of CTX–CTXRT on operative morbidity and mortality has not yet been clarified. The aim of the present study was to document the frequency and nature of morbidity and mortality after surgery combined with CTX–CTXRT, and identify factors predictive of postoperative complications in patients with localized gastric or gastroesophageal adenocarcinoma. Methods A prospectively collected database on 71 consecutive patients who underwent CTX–CTXRT at M.D. Anderson Cancer Center between January 1997 and August 2004 was reviewed. Postoperative morbidity and mortality were investigated, and risk factors for overall complications were identified by multivariate logistic regression analysis. Results Overall morbidity and mortality rates were 38.0% (27 patients) and 2.8% (2 patients), respectively. Age greater than 60 years [relative risk 11.3 (95% confidence interval 2.50–50.6)] and body mass index (BMI) of 26 kg/m2 or above [relative risk 4.08 (95% confidence interval 1.08–15.4)] were significant risk factors for overall complications. Conclusions CTX–CTXRT can be performed safely with an acceptable operative morbidity and a low operative mortality rate in patients with gastric or gastroesophageal cancer, with careful consideration of added risk associated with age and obesity.  相似文献   
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