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71.
72.
A human O6-alkylguanine-DNA-alkyltransferase (ATase) cDNA-containing retrovirus was used to infect murine long-term primary bone marrow cultures. High levels of ATase expression were obtained, and colony- forming cells of the granulocyte-macrophage lineage from the cultures transduced with the human ATase retrovirus were three times more resistant to the alkylating agent, N-methyl-N-nitrosourea (MNU), than control cultures. Furthermore, expression of the human ATase protected long-term hematopoiesis, measured as the output of progenitor cells to the nonadherent fraction of the culture, against the cytotoxic effects of repeated exposures to MNU. These results clearly show that a human ATase cDNA-containing retrovirus can be used to infect long-term primary bone marrow cultures and that this attenuates their sensitivity to nitrosoureas.  相似文献   
73.
目的:探讨输尿管硬镜在尿路疾病治疗中的应用效果。方法:对1000例尿路结石、输尿管及尿道狭窄、输尿管息肉、梗阻、异物存留等患者,均以输尿管硬镜配合其他设备进行治疗。结果:肾内结石34例治愈率76.5%,输尿管结石、膀胱及尿道结石治愈率为94.5%~99.8%;泌尿道狭窄治愈率66.7%~75%;33例泌尿道异物取出率97%。结论:基层医院在尿路疾病治疗中,根据病变的不同部位,将输尿管硬镜灵活配合现有并不高档的设备,同样可以取得较好的微创手术效果。  相似文献   
74.
PURPOSE: The purpose of this work was to describe the human leptomeningeal and cortical vascular anatomy as seen at high resolution on an 8 T UHFMRI system. METHOD: With a 1024 x 1024 matrix, axial gradient echo images of the cerebral cortex were acquired on a human volunteer at 8 T with TR 500 ms, TE 16 ms, flip angle 22.5 degrees, bandwidth 53 kHz, and slice thickness 2.84 mm. The same subject was evaluated at 1.5 T using similar parameters. The images were then reviewed in detail and compared with known cortical and leptomeningeal vascular anatomy. RESULTS: Two hundred forty micron in-plane resolution images of the human brain were acquired at 8 T without evident artifact from susceptibility distortions, RF penetration, or dielectric resonances. The CSF, gray matter, and white matter structures were well discerned. The microscopic leptomeningeal vascular anatomy was well visualized, and the course of small perforating cortical vessels could be followed from the cortical surface to the white matter junction. CONCLUSION: Initial 8 T images of the brain demonstrate detailed leptomeningeal and cortical vascular anatomy.  相似文献   
75.
Cerebral embolisation during modern cardiopulmonary bypass   总被引:1,自引:0,他引:1  
Objectives: Cerebral microembolisation still occurs during cardiopulmonary bypass and may cause both stroke and postoperative cognitive impairment. We investigated the frequency of cerebral embolisation during coronary artery bypass surgery with modern cardiopulmonary bypass and related these to ascending aortic atherosclerosis. Methods: Transcranial Doppler monitoring for cerebral embolisation to both middle cerebral arteries was performed in 65 patients undergoing coronary artery surgery with non-pulsatile alpha-stat hypothermic bypass. Epicardial ultrasound imaging of ascending aortic atherosclerosis was performed in 14 patients. Results: Thirty patients (56.9%) had more than 200 emboli entering the middle cerebral artery territories during surgery; most at the start of bypass and during defibrillation. Readjustment of aortic clamps and aortic cannulation also caused a large number of emboli which were probably particulate. Aortic disease was mild (mean plaque thickness 1 mm, interquartile range 0.9–1.2 mm) and did not relate to the number of cerebral emboli produced by aortic manipulation. Conclusions: Cerebral embolisation remains common during coronary surgery despite advances in filter and bypass pump technology. Aortic manipulation and clamping was associated with emboli but epicardial ultrasound imaging was of little help in its prediction.  相似文献   
76.
BACKGROUND AND PURPOSE: Clayman and associates first described laparoscopic nephrectomy in 1990. This paper describes the first randomized controlled trial to compare laparoscopic with open surgery for simple and radical nephrectomy. PATIENTS AND METHODS: Between 2001 and 2004, 45 patients requiring simple or radical nephrectomy (tumors as large as 8 cm) were randomized to either open surgery through a loin incision or laparoscopic nephrectomy (transperitoneal). Outcome measures included operative time, complications, hospital stay, pain scores, time to return to normal activities, and quality of life scores (EuroQol). RESULTS: The mean operative time was 105 minutes in the laparoscopic group and 93 minutes in the open-surgery group (P = 0.4). Blood loss, complications, and the mortality rate were similar in the two groups, as was the hospital stay at a median of 4 days in the laparoscopic group and 5 days in the open group (P = 0.9). Postoperative visual analog pain scores averaged 3.6 in the laparoscopic group compared with 5.4 in the open group (P = 0.02). There was no difference in pain scores at 3 months. Return to normal activities was faster in the laparoscopic group at 42 days v 62 days in the open group (P = 0.04). CONCLUSIONS: Laparoscopic nephrectomy is associated with less postoperative pain and a faster return to normal activities than open nephrectomy.  相似文献   
77.
BACKGROUND: Porcine antigen primed and CD4+ T-cell activated macrophages are able to migrate to and destroy porcine xenografts. However, the specific signaling mechanisms involved remain to be identified. METHODS: In this study macrophages which lack the universal toll-like receptor (TLR) adaptor MyD88 were used to investigate the role of TLR in the recognition and activation of macrophages in islet xenograft rejection. Macrophages were isolated from rejecting MyD88(-/-) and wild-type C57BL/6 mice that were recipients of neonatal porcine pancreatic cell cluster (NPCC) xenografts, and were transferred to NPCC recipient NOD-SCID mice. RESULTS: Both wild-type C57BL/6 and MyD88(-/-) mice rejected NPCC xenografts 8 and 10 days, respectively after transplantation, and the grafts were heavily infiltrated with CD4+ T cells and macrophages. However, graft infiltrating macrophages from rejecting MyD88(-/-) recipients demonstrated impaired up-regulation of TLR expression and impaired activation phenotype, when compared to those from rejecting C57BL/6 recipients. Transfer of NOD-SCID recipients with macrophages from rejecting C57BL/6 mice resulted in NPCC xenograft rejection along with massively infiltrated macrophages 8 days after transfer, whereas NPCC xenografts in NOD-SCID mice transferred with macrophages from rejecting MyD88(-/-) mice remained intact until the end of this study, 90 days after transfer, with insulin-positive islets and no infiltration by macrophages. CONCLUSION: This study demonstrates that deletion of MyD88 causes impaired macrophage activation after pig islet xenotransplantation. However, graft survival is not prolonged and xenografts are rejected rapidly by alternate mechanisms.  相似文献   
78.
Cardiovascular disease represents a significant portion of pregnancy‐related complications and is associated with high rates of morbidity and mortality in this cohort. Cardiac valvulopathy, and aortic valve pathologies, in particular, pose a significant challenge to women who are pregnant and to the health care professionals who look after them. Depending on the type and severity of aortic valve pathology, pregnancy may exacerbate or accelerate the progression of valvulopathy sequelae because of the hemodynamic changes that occur from conception, throughout gestation, up to Labor and postpartum. Management of such patients ranges from basic conservative measures such as bed‐rest, extending to high‐risk emergency open heart surgery. This nonstructured review aims to highlight the current evidence available relating to the management of aortic valve disease in pregnancy, with a key focus on cases which requires intervention beyond that of medical therapy. In conclusion, the management of aortic valvulopathy in pregnancy is a challenging field with only a small amount of clinical experience and retrospective study supporting evidence‐based decisions in this field. A greater understanding of the most recent advances is recommended to support decision making in this specialist field of clinical medicine.  相似文献   
79.
BACKGROUND: Our aims in the present study were to estimate the influences of pain and urinary symptoms on quality of life, and to determine which of these two variables has the most predictive power with respect to quality of life in young men with chronic prostatitis-like symptoms. METHODS: Chronic prostatitis-like symptoms were measured by the National Institutes of Health-Chronic Prostatitis Symptom Index. Of the 28,841 men aged 20 years who lived in the study community, 18,495 men (a response rate 64.1%) agreed to participate in the study. A total of 1057 men who complained of symptoms indicative of chronic prostatitis were included in the study. The influences of pain and urinary symptoms on quality of life were determined using logistic regression analysis. The receiver operating characteristic (ROC) curve was used to estimate the predictive ability of each of these variables with respect to quality of life. RESULTS: Results from multivariate analysis showed that both pain and urinary symptoms were associated with an increased likelihood of impaired quality of life, although pain contributed more to a reduced quality of life than urinary symptoms. Relative to men who experienced mild pain, men who experienced moderate pain had a 3.9-fold risk of poor quality of life (odds ratio [OR], 3.87; 95% confidence interval [CI], 2.86-5.23; P < 0.001) and those who experienced severe pain had a 15.7-fold risk of reduced quality of life (OR, 15.68; 95% CI, 6.59-37.35; P < 0.001). Moderate urinary symptoms were associated with a 1.4-fold risk of bother (OR, 1.41; 95% CI, 1.01-1.99; P < 0.001) and severe urinary symptoms were associated with 2.4-fold risk (OR, 2.39; 95% CI, 1.37-4.12; P < 0.001), relative to mild urinary symptoms. Comparison of the effects of pain and urinary symptoms showed that pain severity had the most predictive power for bother, quality of life, and quality-of-life impact. The areas under the ROC curves for bother, quality of life, and quality-of-life impact were 71.3%, 69.3% and 72.5%, respectively. CONCLUSION: Urinary symptoms and pain might be associated with an increased likelihood of impaired quality of life in young men with chronic prostatitis-like symptoms. In addition, our findings suggest that pain severity is the most influential variable for determining quality of life in this population.  相似文献   
80.
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