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21.
Summary In blood of 21 anemic patients and 8 normal subjects (N) thre oxygen dissociation curves each were measured at different pH values to calculate Bohr coefficients after acidification with CO2 (BCCO
2) or fixed acid (BCFA), and other important parameters of oxygen affinity. The patients had either low hemoglobin or red cell production (L:n=11, 7.3 g/dl Hb) or high erythrocyte production combined with high loss (H:n=10, 7.8 g/dl Hb). The standard half saturation pressure P50 (pH 7.4, 37°C) was equally elevated in both anemic groups (L:30.5, H:30.8, N:26.7 mmHg), as well as the diphosphoglycerate concentration (DPG) (L:18.7, H:18.6, N:12.7 mol/g Hb). The red cell pH of the anemics was lower than for the N (approximately 0.045 units) causing part of the difference in P50. Hill's ntended to high values in the anemics except at low O2-saturation in the H. For BCCO
2 no significant difference among the groups was observed. BCFA, however, increased in the H at low SO
2 compared to the N and L. The cause for most of the changes in hemoglobin oxygen affinity in anemics was the high [DPG]. The combination of high P50 and high n value as in the L seems to be most advantageous for tissue oxygenation.The measurements were performed during a stay as visiting professor at the Universidad del Valle, supported by Deutscher Akademischer Austauschdienst VS 931 509 0013 相似文献
22.
Wide-field specular microscopy, slit-lamp examination, and pachometry were performed on 22 successful hard contact lens wearers and 22 controls matched for age, race, sex, and refractive error. A minimum of 600 cells per control and 1200 per contact lens wearer were manually digitized from the specular photomicrographs. Frequency distributions of cell areas were compared between the two groups using the parameters of mean, median, standard deviation, coefficient of variation, skewness and kurtosis. Slit-lamp examination was normal and there was no significant difference in corneal thickness between the patient group and the control group. Comparison of mean, median, and standard deviation also revealed no significant difference, but skewness (P less than .001), kurtosis (P less than .001) and coefficient of variation (P less than .004) were greater in the hard contact lens wear group. Hard contact lens wearing time correlated with increasing pleomorphism (P less than .05). Specular microscopy also revealed morphologic changes including deep stromal striae, intra- and extracellular "blackout" areas, and clustering of extremely small and large cells. The possible relationship between endothelial hypoxia and structural stromal changes are discussed. 相似文献
23.
《Neuro-Chirurgie》2021,67(4):383-390
Osteoblastoma of the skull is a rare entity, and they account only for 2-4% of all the cases of osteoblastoma. We perform a comprehensive review of the pertinent literature on the subject and we report a case of a 3-year-old girl presenting with a 6-month history of a supraorbital mass and exophthalmos due to an osteoblastoma of the frontal and ethmoid bones involving the orbit and anterior skull base. A 3D printed model of the patient's skull was used for the preoperative planning and reconstruction strategy. Total en-bloc resection of the tumor followed by immediate reconstruction was achieved. No recurrence was detected 3 years after the surgery. Gross total resection is strongly advised with skull osteoblastoma, especially in young age, because of the risk of the recurrence and malignant transformation. 3D printing is proven to be a valuable tool to enhance surgical performance by avoiding complications while achieving total resection with accurate reconstruction. Long-term follow-up is important to detect recurrences and improve the management of these young patients. 相似文献
24.
《Gaceta sanitaria / S.E.S.P.A.S》2021,35(3):230-235
ObjectiveTo analyse the profile of the persons and associations that participated in the course, quantify peer education activities and analyse their evolution.MethodA quantitative study using an analysis of the course records from 2009 to 2018 was designed for this purpose inside mihsalud program designed to promote health amongst persons in vulnerable situations in the city of Valencia (Spain). It offers a yearly training-action course of community health workers (CHW) that is attended by persons who have been proposed by associations. The associations were defined according to their population (immigrant, local or intercultural) and the CHWs according to gender, country of birth, year of course, association and continuity after training. Means and confidence intervals were calculated at 95% and a bivariate analysis was conducted in order to compare the activities that took place in 2009 to 2013 with those of 2014 to 2018. The time trends were analysed by applying linear regression models that included the different years studied as the dependent variable.Results201 CHW of 31 nationalities were trained, 81.6% (95% confidence interval [95% CI]: 75.5-86.7] were women. Eighty-two associations participated, 51.2% (95% CI: 39.9-62.4] worked with culturally diverse populations. Participation by associations (p = .017) and CHWs (p = .377) increased in a statistically significant manner over the years. After the course, 35.3% (95% CI: 28.7-42.4] of the CHWs continued to collaborate voluntarily in the associations.ConclusionsThe results of the CHW training-action course improve over time given that a significant increase in participation by associations and women can be seen, along with a greater number of activities completed during the training. One effect of this is that CHWs are contracted or carry out voluntary activities in the associations. 相似文献
25.
三维CT在颅底缺损重建中的作用 总被引:1,自引:0,他引:1
目的 用三维CT技术进行颅底重建手术的分析、设计、提高一期重建的成功率。方法 手术前联合采用三维CT、MRI或CT了解病变与颅底的关系,颅底缺损的大小、范围及所涉及的重要结构。根据不同情况设计相应手术方案,以自体骨、颞肌瓣和硅橡胶为修复材料。结果 10例中1例颅骨纤维结构不良者发生脑膜炎。3周后痊愈。余9例无类似或组织下垂、脑脊液鼻漏等并发症。结论 三维CT为分析颅底重建手术方案提供了立体分析资料,同时也为手术后评价颅底重建效果提供了直接的实体影像。 相似文献
26.
Objectives To evaluate the efficacy of early arytenoid adduction in the management of vagal paralysis after skull base surgery. Study Design Retrospective evaluation at a tertiary care skull base center. Methods Aggressive surgical management of skull base lesions has become increasingly popular owing to advances in surgical technique and intraoperative monitoring. Temporary and permanent lower cranial neuropathies occur frequently, especially after the surgical management of lesions involving the vertebrobasilar system and the jugular foramen. An injury to the proximal vagus nerve is usually associated with dysphonia and swallowing dysfunction. An early arytenoid adduction has been employed in 26 patients with a vagal paralysis after skull base surgery. Most commonly, the neurosurgical patient underwent an arytenoid adduction under general anesthesia on postoperative day 2. Results Videostroboscopy after arytenoid adduction demonstrated 76% of patients had complete glottic closure. Of those with inadequate glottic closure, all demonstrated a well‐medialized posterior glottis with a persistent anterior glottal gap. These patients were easily treated with a secondary type I thyroplasty under local anesthesia with sedation resulting in complete glottic closure. Despite excellent voice outcomes, 66% of these patients had dysphagia requiring enteral feedings for nutritional support. Conclusions An early arytenoid adduction is an excellent medialization technique that can be performed safely in the early postoperative period under general anesthesia after skull base surgery. 相似文献
27.
目的:探讨应用针形内窥镜对小儿鼻颅底疾病进行探查与手术的方法及疗效。方法:在外径1.9mm的进口针形内窥镜及电视同图像系统监视下,对8例小儿(7d ̄12岁)鼻颅底有关疾病进行探杳与手术。结果:先天性后鼻孔闭锁3例中,1例好转,3例痊愈。外伤性脑脊液鼻漏1例,经修补痊愈先天性脑膜脑膨出2例,确诊后1例暂缓治疗。另1例行内窥镜手术痊愈。颅底神经母细胞瘤2例取材作病理检查确诊。结论:在电视图像监视下应用 相似文献
28.
起始密码下游序列与16srRNA3′端序列的匹配性对基因表达效率的影响 总被引:1,自引:0,他引:1
目的 :研究起始密码下游序列与 16srRNA 3′端 +146 9——— +1482局部序列间的匹配关系对基因表达效率的影响。方法 :我们一方面对人IL_2、人IL_8、人IL_6 ,人GM_CSF、人G_CSF、人IL_1ra、人IL_9等全长cDNA序列及 5′末端局部序列与 16srRNA 3′端 +146 9——— +1482序列进行匹配性进行分析 ,寻找序列匹配性与表达效率间的关系 ;另一方面 ,对人IL_6、人GM_CSFcDNA 5′端序列进行沉默突变 ,增强其与 16srRNA 3′端 +146 9——— +1482序列间的匹配性 ,并克隆入pKpL4表达型质粒载体 ,通过大肠杆菌进行表达 ,实验验证序列匹配性与基因表达效率的关系。结果 :分析发现起始密码下游局部序列与 16srRNA 3′端 +146 9——— +1482核酸匹配性越好 ,则目的蛋白表达效率越高 ;目的基因编码区内与 16srRNA 3′ +146 9——— +1482间的最大匹配区域越靠近 5′末端 ,目的蛋白表达效率越高。通过对人IL_6、人GM_CSFcDNA 5′末端序列进行沉默突变 ,改善其与 16srRNA 3′端 +146 9——— +1482序列的匹配性后 ,目的蛋白的表达量均呈不同程度地提高。结论 :提高起始密码下游序列与 16srRNA 3′端 +146 9——— +1482局部序列间的匹配性 ,可增强目的基因的表达效率。 相似文献
29.
目的:探讨临床常用药物对人体酸碱平衡的影响,指导临床工作。方法:用酸度计测定九种药品pH值,计算氢离子浓度。结果:偏碱性的药物有50g/L碳酸氢钠,谷氨酸钠、谷氨酸钾注射液;偏酸性的药物有盐酸精氨酸、维生素C、各种浓度葡萄糖注射液、氯化钠注射液。结论:临床上一些常用药品会影响人体的酸碱平衡,尤其在机体酸碱平衡调节发生障碍的情况下,更应谨慎。 相似文献
30.