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121.
To investigate the possible contribution of cellular immunity in the development of radiation injury of the central nervous system, Wag/Rij rats were thymectomized at birth and irradiated to the cervical spinal cord at the age of 3 months. At the time of paralysis or at the end of the follow-up period (when rats were 1-year-old) the animals were sacrificed and the mediastinum was examined histologically. In 95% of the neonatally thymectomized animals no thymus was left. These rats showed a firm impairment of the cellular immunity, as they had a 40% reduction of the T-lymphocytes in the spleen, and a 70% reduction of the mixed lymphocyte reaction, compared to age-matched controls. Both single dose and two-fraction irradiation experiments were performed. No modification of the latency time to develop paralysis was observed comparing thymectomized and age-matched controls. The incidence of foreleg paralysis after cervical spine irradiation (single dose or two-fraction) was identically distributed in the follow-up period for both neonatally thymectomized and control Wag/Rij rats. The ED50 value derived in the single dose experiments was 20.3 Gy for the control animals, and 20.9 Gy for thymectomized rats, and in the two fraction experiments 29 Gy for controls and 29.6 Gy for thymectomized rats. None of these differences are significant. It appears that neonatal thymectomy, in spite of its firm suppression of the cellular immunity, has no major influence on the development of radiation myelopathy in rats.  相似文献   
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Nucleus24型人工耳蜗植入后的电极有效性   总被引:1,自引:0,他引:1  
目的:随访耳蜗植入后出现蜗外电极或坏损电极的情况,评价人工耳蜗植入后电极的有效性。方法:1998年6月至2002年8月53例Nucleus CI24M型耳蜗植入者,在术中及术后映射调图时进行电极阻抗测试,确定有无电极坏损及其坏损时间。开机时拍摄耳蜗位X线平片,确定电极是否完全植入。分析手术过程和术者经验对电极有效性的影响。结果:电极出现坏损的比例为13.2%,电极在术中插拔两次以上而造成电极坏损的危险度为0.4656。4年累积生存率达96.2%。不完全植入的比例为15.1%,其中又以耳蜗形态异常者居多(7/11)。结论:Nucleus CI24M型植入体在开机1~4年内的可靠性较高。电极序列在术中插拔两次以上,是导致电极坏损的主要原因。患者耳蜗的纤维化、畸形以及术者经验等因素可能导致电极不完全插入。  相似文献   
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125.
BACKGROUND: Retroperitoneal leiomyosarcomas (RLMS) are a challenging clinical entity. The vast majority of patients are operated on when tumors are advanced. We report herein a case of RLMS, mimicking acute appendiceal disease and treated successfully via laparoscopy. METHODS: A 37-year-old woman, para 1, was admitted to our department for right lower quadrant abdominal pain, fever, and leukocytosis. She had no changes in gastrointestinal and urologic function. A physical examination revealed the presence of abdominal guarding, rebound, and a tender mass in the right lower quadrant. The abdominal ultrasound showed an inhomogeneous ovoid mass (6 cm in diameter) located below the cecum, with no definite margins, and consistent with an appendiceal abscess. The patient was referred for laparoscopy. The procedure was performed with the aid of 3 ports: a 12-mm trocar in the umbilicus (open technique), a 10-mm trocar in the left iliac fossa, and a 5-mm one in the supra-pubic space. On inspection of the abdominal cavity, a retroperitoneal 6-cm mass was immediately found below the cecum and the appendix. Neither intraperitoneal seeding nor suspected lymph nodes were present. After dissection of the parietal peritoneum, the mass appeared to be encapsulated and well demarcated from all surrounding structures. It was eventually dissected and removed via a plastic bag. A standard appendectomy was also performed. The postoperative course was uneventful, and the patient was discharged on the 3rd day. The histology analysis of the resected specimen showed a totally excised G2 leiomyosarcoma. The appendix had no signs of inflammation. Postoperatively, the patient underwent a total-body CT-scan, which had no signs of residual or distant disease. No adjuvant therapy was necessary. At an 18-month follow-up, the patient was doing well and was disease free. CONCLUSION: Surgery represents the main therapeutic option for resectable RLMS. Laparoscopy is a useful diagnostic tool that allows safe resection of incidentally discovered, small and well encapsulated RLMS.  相似文献   
126.
The European Society of Thoracic Surgeons (ESTS) organized a workshop dealing with lymph node staging in non-small cell lung cancer. The objective of this workshop was to develop guidelines for definitions and the surgical procedures of intraoperative lymph node staging, and the pathologic evaluation of resected lymph nodes in patients with non-small cell lung cancer (NSCLC). Relevant peer-reviewed publications on the subjects, the experience of the participants, and the opinion of the ESTS members contributing on line, were used to reach a consensus. Systematic nodal dissection is recommended in all cases to ensure complete resection. Lobe-specific systematic nodal dissection is acceptable for peripheral squamous T1 tumors, if hilar and interlobar nodes are negative on frozen section studies; it implies removal of, at least, three hilar and interlobar nodes and three mediastinal nodes from three stations in which the subcarinal is always included. Selected lymph node biopsies and sampling are justified to prove nodal involvement when resection is not possible. Pathologic evaluation includes all lymph nodes resected separately and those remaining in the lung specimen. Sections are done at the site of gross abnormalities. If macroscopic inspection does not detect any abnormal site, 2-mm slices of the nodes in the longitudinal plane are recommended. Routine search for micrometastases or isolated tumor cells in hematoxylin-eosin negative nodes would be desirable. Randomized controlled trials to evaluate adjuvant therapies for patients with these conditions are recommended. The adherence to these guidelines will standardize the intraoperative lymph node staging and pathologic evaluation, and improve pathologic staging, which will help decide on the best adjuvant therapy.  相似文献   
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128.
A group of blood donors involved in post-transfusion hepatitis was investigated for the presence of the anti-HCV antibody and of HCV RNA as a more direct infection marker. RNA was extracted from serum, reverse transcribed and amplified using primers which belonged to the non structural region. The amplified product of the PCR reaction was 582 base pairs. Seven (25.9%) of the 27 blood donors examined were found anti-HCV-positive by ELISA; five (71.4%) of these were HCV RNA positive. Among the 20 anti-HCV-negative blood donors, four (20.0%) were HCV RNA positive. ALT levels were below 45 UI/l in 18 donors, while the other nine had ALTs over the limit accepted for transfusion. The anti-HCV-negative HCV RNA-positive blood donors had normal ALTs. Our study offers a direct explanation for the substantial proportion of residual cases of anti-HCV-positive post-transfusion hepatitis and suggests the necessity of creating a register of blood donors who have at some time presented blood enzyme abnormalities and for whom second level investigations such as HCV RNA should be used.  相似文献   
129.
In this report, the effects of adenosine on the promyelocytic cell line HL-60 and on T-lymphocytic clones are compared. According to previous reports, adenosine induces a dose-dependent inhibition of DNA synthesis in T-lymphocytes. Conversely, adenosine dose-dependently enhances DNA synthesis in HL-60 cells, as documented with [3H]thymidine uptake studies and flow cytometric cell-cycle analysis. Unlike its effect on lymphocytes, the adenosine effect on HL-60 cells does not seem to be mediated by receptor binding, but it appears to be correlated with an intracellular mechanism following active uptake. Despite the different effects exerted by adenosine on lymphocytes and myeloid cells, a purinergic pathway appears to be more generally involved in the regulation of some phases of cell growth.  相似文献   
130.
Iron deficiency anemia is the most frequent haematological pathology in pregnancy. Serum ferritin levels represent the state of iron deposits. Low levels are a sure sign of iron deficiency. At the University of Turin we studied the variations of serum ferritin levels during physiological pregnancy and the sensitivity of routine blood tests with respect to serum ferritin levels. Routine haematological blood values along with ferritin levels were measured in 115 patients throughout pregnancy. The mean serum ferritin level was 56 ng/ml in the first trimester, 27.2 ng/ml in the second and 11.8 ng/ml in the third. The incidences of anemia per trimester was 6.6%, 4.8% and 49% respectively (p less than 0.05, chi squared). Our results show that it is important to evaluate iron deposits early in pregnancy by measuring serum ferritin levels in order to determine the need for iron therapy.  相似文献   
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