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81.
There are many reports on position-related complications in neurosurgical literature but so far, continuous quantification of the patient’s position during the surgery has not been reported. This study aims to explore the utility of a new surgical table system and its software in displaying the patient’s body positions during surgery on real-time basis. More than 200 neurosurgical cases were monitored for their positions intra-operatively. The position was digitally recorded and could be seen by all the members in the operating team. It also displayed the three-dimensional relationship between the head and the heart positions. No position-related complications were observed during the study. The system was able to serve as an excellent indicator for monitoring the patient’s position. The recordings were analyzed and even used to reproduce or improve the position in the subsequent operations. The novel technique of monitoring the position of the head and the heart of the patients and the operating table planes are considered to be useful during delicate neurosurgical procedures thereby, preventing inadvertent procedural errors. This can be used to quantify various surgical positions in the future and define safety measures accordingly.  相似文献   
82.
目的 探讨去氢表雄酮(DHEA)的体内抗癌作用及其机制.方法 Buffalo大鼠21只随机分为空白对照组、肿瘤对照组(把Morris肝细胞瘤移植到大鼠的两肋皮下,建立Morris肝细胞瘤移植的Buffalo大鼠的体内模型,基础饲料喂养)、DHEA肿瘤组(建立Morris肝细胞瘤移植模型后,在喂养的基础饲料中添加DHEA)和去氢表雄酮硫酸酯(DHEAs)肿瘤组(建立Morris肝细胞瘤移植模型后,在喂养的基础饲料中添加DHEAs).分别喂养4周后,Western blot和免疫组织化学方法检测磷酸化丝/苏氨酸蛋白激酶(Akt)、PTEN等蛋白的表达,流式细胞术检测大鼠CD3,CD4、CD8和CD4/CD8.单因素方差分析对数据进行处理.结果 DHEA肿瘤组的肝细胞瘤的质量为(8.31±0.61)g,较肿瘤对照组的(14.57±0.56)g显著减轻(P<0.05).Westem blot及免疫组织化学染色结果显示,DHEA肿瘤组的磷酸化Akt蛋白表达量降低,而PTEN蛋白表达增强;CD3阳性细胞百分率(74.97%±8.29%)较肿瘤对照组(56.45%±6.12%)明显提高(t=4.92,P<0.05),CD4/CD8比值升高(1.75±0.22).而DHEAs肿瘤组CD3阳性细胞百分率(60.04%±6.69%)较空白对照组(75.38%±9.76%)明显降低(t=3.87,P<0.05),同时CD4/CD8比值也降低(1.48±0.56).结论 DHEA对体内的肿瘤具有明显的抑制作用,此作用可能是其通过调节体内的Akt信号传导通路和免疫功能来完成的.  相似文献   
83.
BACKGROUND: In Japan, mass screening for neuroblastoma has been performed at 6 months of age to improve the prognosis of this condition for more than 20 years. In recent years, most neuroblastomas detected by mass screening were considered to have favorable biological features and sometimes tend to regress spontaneously. METHODS: The authors established non-treated observation criteria in 1997 and criteria for observation of residual tumor after first-line chemotherapy in 1999, and have made an effort to reduce the intensity of medical treatment for neuroblastoma. The authors examined outcomes of 79 patients who were found in the Shizuoka neuroblastoma mass screening at 6 months of age and who received medical treatment or underwent observation in Shizuoka Children's Hospital, Shizuoka, Japan, between December 1981 and December 2004. RESULTS: A total of 77 patients survived but the remaining two patients died from complications of medical treatment. None of the patients died due to progression of neuroblastoma. In the cases, non-treated observation was performed in 17. Of those, 12 patients are now under non-treated observation. Of their tumors, two have disappeared, nine have become smaller and another one has not change in size. Observation of residual tumor after first-line chemotherapy was performed in 15 cases, and three disappeared and the other 12 cases became smaller. Medical treatment-related complications were observed in 20 of 67 patients who received medical treatment, and 18 of the 20 patients were seen before establishing non-treated observation criteria. CONCLUSION: Non-treated observation and observation of residual tumor after first-line chemotherapy were useful to reduce medical treatment-related complications.  相似文献   
84.
In 44 neonates (mean birthweight 1207 g and mean gestational age 30.0 weeks), very small central venous catheters were percutaneously inserted via the great saphenous vein on 46 occasions. Catheter-related complications such as catheter blockages in 17 (37%), edema in a unilateral leg in three (6%), and mechanical disruption in two (4%) were noted. Although two of the neonates were found to have bacteremia and five neonates died, none were catheter related. The optimal length of catheter insertion (Y) from the great saphenous vein at the level of the medial maleollus to the inferior vena cava at T9 and L3 was calculated by regression equations utilizing total body length (X). Radiographs taken with extended and flexed leg postures revealed that the catheter tips were retracted with extension of the lower extremities and the degree of displacement ranged from 1 to 4 (mean 2.7) vertebral levels. Because this movement might cause migration into veins that connect to the inferior vena cava, the catheter tip should be located between T9 and L3, except at the renal vein junction. Percutaneous central venous catheterization via the great saphenous vein is safe and useful. Regression equations provided for rapid estimation of the optimal length of insertion.  相似文献   
85.
We report on a patient with cyclic neutropenia who was treated by granulocyte colony-stimulating factor (G-CSF) and high-dose immunoglobulin. The serial examination revealed cyclic fluctuations in the numbers of neutrophils, monocytes, platelets in peripheral blood, and in the serum G-CSF concentration. Bone marrow examination confirmed a cyclic fluctuation of both progenitor cells (CFU-GM) and CD10-positive B cells. The therapy of G-CSF followed by high-dose immunoglobulin achieved a disappearance of neutrophil oscillations. It suggested that the combination therapy of G-CSF with high-dose immunoglobulin might be effective for cyclic neutropenia.  相似文献   
86.
A 9 year old boy with acute lymphoblastic leukemia (ALL) received recombinant human granulocyte colony-stimulating factor (rhG-CSF) and showed a marked increment of myeloblasts in the peripheral blood. He was administered repeated courses of intermediate-dose cytosine arabinoside (Ara-C) therapy (1500 mg/m2, days 1–5) for frequent central nervous system (CNS) relapse of ALL. The peripheral white blood cell nadir was less than 1000/μL, so he was treated with rhG-CSF. A marked increment of peripheral blood blasts was noted 3–5 days after rhG-CSF treatment. These cells decreased with the appearance of mature myeloid cells and disappeared about 2 weeks after the start of treatment. These findings suggested that the blasts might have the ability to differentiate into mature myeloid cells. A control patient with repeated CNS relapse of ALL showed no increment of peripheral blood blasts after similar repeated courses of Ara-C without rhG-CSF treatment. Cultured peripheral blood blasts obtained from the present patient showed differentiation into mature myeloid cells by morphological studies and surface marker analysis. These findings indicate that the peripheral blood blasts drawn by G-CSF were not leukemic blasts but normal myeloblasts.  相似文献   
87.
Subchronic Oral Toxicity of Glyoxal via Drinking Water in Rats   总被引:2,自引:0,他引:2  
Subchronic Oral Toxicity of Glyoxal via Drinking Water in Rats.Ueno, H., Segawa, T., Hasegawa, T., Nakamuro, K., Maeda, H.,Hiramatsu, Y., Okada, S., and Sayato, Y. (1991). Fundam. Appl.Toxicol. 16, 763–772. The subchronic oral toxicity ofglyoxal via drinking water and the effect on in vivo proteinsynthesis in tissues following a single treatment with thissubstance were assessed in Sprague–Dawley male rats. Animalsreceived drinking water containing glyoxal levels of 2000, 4000,and 6000 mg/liter ad libitum for 30, 60, and 90 days in PhaseI. In Phase II, the high-dose and control-1 groups fed the dietad libitum, and a diet-limited control-2 group given the sameamount of diet as consumed by the high-dose group were maintainedfor 90 and 180 days. The study designs included observationsof clinical signs, body weights, major organ weights, grossand histopathological examinations, serum clinical chemistry,and biochemical examinations such as glyoxalase activity andglutathione content in selected tissues. Body weight gain andorgan weights significantly decreased with dosage. Althoughconsumption of food and water was also depressed in the exposedgroup, the reduction of body weight gain was greater in thehigh-dose group than in the diet-limited control 2 group. Histopathologicalexaminations revealed only a slight papillary change in thekidneys from the high-dose group at both 90 and 180 days terminationsin Phase II. The induction of both glyoxalase I and II was observedin liver and erythrocytes at 30-day termination of the exposedgroups. Serum enzyme and protein levels were significantly reducedby the mid- and/or high-dose exposures. With a single oral high-dosetreatment of glyoxal, a great decline in the incorporation ofL-[3H]leucine was shown particularly in the liver, and thisprobably led in part to a reduction in the serum protein levelsin rats following subchronic exposure to glyoxal. These dataindicated an overall low degree of systemic toxicity to ratsexposed subchronically to glyoxal via drinking water.  相似文献   
88.
To assess the relationship between the glomerular injury induced by immune complex deposition and proteinuria, ultrastructural changes of the glomerular basement membrane (GBM) were investigated in Heymann nephritis. Active Heymann nephritis was induced in rats by injecting them with tubular brush border antigen, known as Fx1A, emulsified in complete Freund's adjuvant (CFA). Measurement of urinary protein excretion and histological examinations were carried out for up to 15 weeks after immunization. Proteinuria developed in rats within 10 weeks of immunization and coincided with the development of subepithelial deposits with minimal spike-like basement membrane protrusion. Acellular glomeruli were prepared by detergent treatment and were subjected to tannic acid–osmium conductive staining prior to examination with an ultrahigh resolution scanning electron microscope (HSEM). HSEM of the acellular GBM prepared from control rats injected with CFA alone revealed a meshwork structure, with pores of about 9 nm in diameter. Proteinuric rats immunized with Fx1A showed a loosened meshwork structure, with pores of about 15 nm in the acellular GBM adjacent to the deposits. The newly formed GBM overlying the deposit consisted of a meshwork structure associated with unorganized thin fibrils. Ultrastructural changes were never seen in GBM devoid of deposits. These findings indicate that subepithelial deposits are closely involved in the development of proteinuria by injuring the size selectivity of the GBM.  相似文献   
89.
Abstract A 45 year old Japanese man with alcoholic hepatitis developed thrombocytopenia together with an increase in the level of platelet-associated immunoglobulin G (PAIgG). Bone marrow aspiration revealed a normal nucleated cell count and a slight increase of megakaryocytes. After abstinence from alcohol, laboratory and symptomatic improvement occurred in association with a prompt increase in the platelet count and a corresponding decrease of PAIgG. These findings suggest that PAIgG may have been involved in the development of thrombocytopenia in this patient.  相似文献   
90.
A 57 year old Japanese male was incidentally found to have a 7.5 cm diameter hepatic haemangioma. Eleven years later he was operated on because the haemangioma had grown into a 17 cm mass causing upper abdominal fullness. Volumetry on computerized tomograms disclosed that the haemangioma had grown from 123 cm3 to 1343 cm3 in volume. Quantitative documentation on growing hepatic haemangioma has been rare.  相似文献   
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