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71.
The purpose of this study was to investigate the sinus node artery in the sheep heart to establish adequate baseline information for use in cardiovascular research, and to compare this information with similar data for man. The coronary arteries were exposed by using injection-corrosion casting technique in 60 sheep hearts. Polyester and diluted sulfuric acid were used. When the corrosion was completed, the specimens were photographed. The sinus node artery was single in 59 specimens, and double in one specimen. The artery originated from the right coronary artery (in 42 specimens), left coronary artery (in 16 specimens), and right aortic sinus (in 1 specimen). In the majority of specimens, sinus node artery corresponded to the right superior (anterior) atrial artery. Pericaval termination was common. Mean measurements about the sinus node artery were tabulated. According to the present study, we can state that the sinus node artery in sheep heart is similar to that of humans. Because of the importance of animal research, we suggest that experimental surgical studies of the sinus node artery should be performed on the sheep heart. 相似文献
72.
73.
Organ transplantation offers children in acute or chronic severe organ failure similar opportunities to adults. However, while the number who might benefit is relatively low, significantly fewer cadaveric donors exist for any given child compared with an adult. Incompatible organ size and relatively low donation rates mean that despite living parental donation and innovations to reduce donated organ size, children die before organs become available. The severity of the UK situation is compounded by restrictions on paediatric living donation, uncertainties over the application of brain death criteria, and ethical concerns about the use of donation after circulatory death. The UK Department of Health's Organ Donation Task Force suggested the means by which the adult donor pool might be increased, recommending that outstanding ethical and legal issues be resolved, but made no specific recommendations about children. 相似文献
74.
75.
Kiran RP Kirat HT Burgess AN Nisar PJ Kalady MF Lavery IC 《Annals of surgical oncology》2012,19(4):1206-1212
Purpose
Adjuvant chemotherapy is currently offered, as standard, after curative resection for patients with rectal cancer who receive neoadjuvant chemoradiation (NCRT). We postulate that adjuvant chemotherapy adds minimal oncologic benefit for patients who undergo total mesorectal excision who are node-negative after neoadjuvant chemoradiation. 相似文献76.
Tekgül S Riedmiller H Hoebeke P Kočvara R Nijman RJ Radmayr C Stein R Dogan HS 《European urology》2012,62(3):534-542
Context
Primary vesicoureteral reflux (VUR) is a common congenital urinary tract abnormality in children. There is considerable controversy regarding its management. Preservation of kidney function is the main goal of treatment, which necessitates identification of patients requiring early intervention.Objective
To present a management approach for VUR based on early risk assessment.Evidence acquisition
A literature search was performed and the data reviewed. From selected papers, data were extracted and analyzed with a focus on risk stratification. The authors recognize that there are limited high-level data on which to base unequivocal recommendations, necessitating a revisiting of this topic in the years to come.Evidence synthesis
There is no consensus on the optimal management of VUR or on its diagnostic procedures, treatment options, or most effective timing of treatment. By defining risk factors (family history, gender, laterality, age at presentation, presenting symptoms, VUR grade, duplication, and other voiding dysfunctions), early stratification should allow identification of patients at high potential risk of renal scarring and urinary tract infections (UTIs). Imaging is the basis for diagnosis and further management. Standard imaging tests comprise renal and bladder ultrasonography, voiding cystourethrography, and nuclear renal scanning. There is a well-documented link with lower urinary tract dysfunction (LUTD); patients with LUTD and febrile UTI are likely to present with VUR. Diagnosis can be confirmed through a video urodynamic study combined with a urodynamic investigation. Early screening of the siblings and offspring of reflux patients seems indicated.Conservative therapy includes watchful waiting, intermittent or continuous antibiotic prophylaxis, and bladder rehabilitation in patients with LUTD. The goal of the conservative approach is prevention of febrile UTI, since VUR will not damage the kidney when it is free of infection. Interventional therapies include injection of bulking agents and ureteral reimplantation. Reimplantation can be performed using a number of different surgical approaches, with a recent focus on minimally invasive techniques.Conclusions
While it is important to avoid overtreatment, finding a balance between cases with clinically insignificant VUR and cases that require immediate intervention should be the guiding principle in the management of children presenting with VUR. 相似文献77.
Giant aneurysm of the azygos pericallosal artery: case report and review of the literature 总被引:3,自引:0,他引:3
BACKGROUND: Pericallosal aneurysms are encountered less than 6.7%, and giant aneurysms among them even less. Giant azygos pericallosal artery aneurysm at the callosomarginal bifurcation is extremely rare, and our case presented herein is the second one. The case is discussed with thorough review of the literature. METHODS: A 65-year-old woman presented with an extremely rare giant aneurysm on the azygos pericallosal artery manifesting as subarachnoid hemorrhage in World Federation of Neurosurgical Societies Grade 3. Computed tomography (CT), magnetic resonance angiography (MRA), and four vessel angiography revealed a giant azygos pericallosal artery aneurysm associated with a second aneurysm at the left M1. RESULTS: After recovery to Grade 2, she underwent surgery via the right frontal interhemispheric approach for the azygos artery aneurysm on the 17th day after bleeding. The true dimensions of the aneurysm were greater than indicated by angiography because of partial thrombosis. Trilobulate aneurysm was carefully dissected from the surrounding structures. Postoperative cerebral angiography showed no filling of the clipped aneurysm and preservation of circulation. CONCLUSIONS: The treatment of distal anterior cerebral artery aneurysms is often difficult, because of their broad-based irregular configurations and adherence to surrounding tissue, tendency to bleed irrespective of size and the coexistence of other cerebral aneurysms. However, excellent outcomes can be obtained based on thorough preoperative radiologic evaluation, including magnetic resonance imaging (MRI), and correct selection of surgical approach. 相似文献
78.
Sammy Saab Rafik M. Ghobrial Ayman B. Ibrahim Gregg Kunder Francisco Durazo Steven Han Douglas G. Farmer Hasan Yersiz Leonard I. Goldstein Ronald W. Busuttil 《American journal of transplantation》2003,3(9):1167-1172
Hepatitis C (HCV)-positive liver grafts have been increasingly used in patients with decompensated liver disease from HCV because of critical shortage of available organs. Fifty-nine recipients of HCV-positive grafts were matched to patients who received HCV-negative grafts. All recipients were transplanted for HCV liver disease. Matching variables were (1) status, (2) pre-transplant creatinine, (3) recipient age, (4) donor age, (5) warm ischemia time, and (6) year of transplantation. Both unmatched and matched analyses were performed on patient survival, graft survival, and time to HCV recurrence. There was no significant statistical difference in patient, graft, or HCV recurrence-free survival between recipients of HCV-positive and HCV-negative grafts with matched and unmatched analyses (p > 0.05). The 3-year estimates of HCV disease-free survival were 12% (+/- 9%) and 19% (+/- 7%) using HCV-positive and -negative grafts, respectively. The use of HCV-positive grafts in recipients with HCV does not appear to affect patient survival, graft survival, or HCV recurrence when compared with the use of HCV-negative grafts. Our results suggest that HCV-positive grafts can be used in a HCV liver transplant recipient. 相似文献
79.
Jung K Krell HW Ortel B Hasan T Römer A Schnorr D Loening SA Lein M 《The Prostate》2003,54(3):206-211
BACKGROUND: Matrix metalloproteinases (MMPs) play an important role in invasion and metastatic spread of cancer cells. The objective of this study was to assess MMPs in plasma of Dunning tumor rats as indicators of the progression of prostate cancer and follow-up parameters after treatment. METHODS: Prostate cancer was induced in male Copenhagen rats by either subcutaneous or orthotopic implantation of R3327-MatLyLu cells. During the development of the tumor, plasma MMP-2, and MMP-9 were measured by gelatin-substrate zymography and Western blot technique with densitometry in untreated animals, rats treated with laser-induced hyperthermia, or with the new synthetic MMP inhibitor RO 28-2653. RESULTS: Normal prostatic tissue of the Copenhagen rats predominantly expressed proMMP-2 but not proMMP-9 whereas MMP-9 was only found in cancerous tissue. Elevated plasma MMP-9 values were demonstrated in rats with subcutaneous or orthotopic tumors. Animals with tumors and treated with the MMP inhibitor RO 28-2653 had both a lower tumor volume and a lower plasma MMP-9 concentration compared with controls. CONCLUSIONS: The determination of plasma MMP-9 in Dunning tumor rats is a useful tool to monitor the progression of prostate cancer and to assess the efficacy of drugs like MMP inhibitors or other treatment protocols. 相似文献
80.
High ligation to treat pain in varicocele 总被引:3,自引:0,他引:3
Purpose: There are limited data about the effectiveness of surgery in patients withpainful varicocele. We report a retrospectivestudy done for the follow up on all varicocelehigh ligations performed for pain to evaluatethe effectiveness of the operations.Materials and methods: The patients who were all physically active workers and who underwent high inguinal ligation of varicocelefor pain from January 1995 to January 2000,were invited for interviews. Their charts werereviewed to document patient age, grade andlocation of varicocele, duration and quality ofpain, response to conservative treatment. Allpatients who could be contacted were interviewed for resolution of pain and complications, their physical examinations were made.Results: 87 of 140 (62.1%) patients wereavailable for the follow up. Median patient agewas 26 (15 to 34) years old. The varicocele wason the left side in 82 patients and bilateralin 5. The pain was dull in 42, throbbing in 25,sharp in 6 and as a pulling sensation in 14.The longest conservative therapy given in theliterature failed in all patients. Varicocelegrades were as follows: Grade I in 17, Grade IIin 34 and Grade III in 36 patients. Highinguinal ligation was used in all patients. 72(82.8%) patients reported complete resolution, 8 (9.2%) patients reported partial response, 7(8%) patients had persistant pain.Conclusions: High inguinal ligation iseffective in the treatment of painfulvaricocele in highly selected patients.Prospective randomized studies are neededcomparing surgical and conservativetreatments. 相似文献