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61.
Doufas AG Akça O Barry A Petrusca DA Suleman MI Morioka N Guarnaschelli JJ Sessler DI 《Anesthesia and analgesia》2002,95(6):1752-6, table of contents
Even mild hypothermia provides marked protection against cerebral ischemia in animal models. Hypothermia may be of therapeutic value during neurosurgical procedures. However, current cooling systems often fail to induce sufficient hypothermia before the dura is opened. Furthermore, they usually fail to restore normothermia by the end of surgery, thus delaying extubation. We evaluated a new internal heat-exchanging catheter. Eight ASA physical status II-IV patients (29-72 yr) undergoing craniotomy were enrolled. After the induction of general anesthesia, we introduced the SetPoint catheter into the inferior vena cava via a femoral vein. The target core body temperature was 34 degrees C-34.5 degrees C. After reaching the target, core temperature was maintained until the dura was closed. Target core temperature was then set to 37.0 degrees C, and the patient was rewarmed as quickly as possible. Seven patients had a tumor resection, and one had an aneurysm clipped. The core-cooling rate was 3.9 degrees C +/- 1.6 degrees C/h, and the rewarming rate was 2.0 degrees C +/- 0.5 degrees C/h; core temperature was 35.9 degrees C +/- 0.2 degrees C by the end of surgery. Patients were subsequently kept normothermic for 3 h before the catheter was removed. No thrombus or other particulate material was identified on the extracted catheters. None of the patients suffered any complications that could be attributed to the SetPoint system or thermal management. IMPLICATIONS: Because current systems for inducing therapeutic hypothermia are too slow, we tested an internal counter-current thermal management system during hypothermic neurosurgery. The SetPoint catheter cooled at 3.9 degrees C +/- 1.6 degrees C/h and rewarmed at 2.0 degrees C +/- 0.5 degrees C/h. Catheter-based internal thermal management thus seems to be rapid and effective. 相似文献
62.
BACKGROUND: Wound infections are common, serious, surgical complications. Oxidative killing by neutrophils is the primary defense against surgical pathogens and increasing intraoperative tissue oxygen tension markedly reduces the risk of such infections. Since hypercapnia improves cardiac output and peripheral tissue perfusion, we tested the hypothesis that peripheral tissue oxygenation increases as a function of arterial carbon dioxide tension (PaCO(2)) in anesthetized humans. METHODS: General anesthesia was induced with propofol and maintained with sevoflurane in 30% oxygen in 10 healthy volunteers. Subcutaneous tissue oxygen tension (PsqO(2)) was recorded from a subcutaneous tonometer. An oximeter probe on the upper arm measured muscle oxygen saturation. Cardiac output was monitored noninvasively. PaCO(2) was adjusted to 20, 30, 40, 50, or 60 mmHg in random order with each concentration being maintained for 45 min.(2) (2) RESULTS: Increasing PaCO(2) linearly increased cardiac index and PsqO(2) : PsqO(2) = 35.42 + 0.77 (PaCO(2)), < 0.001. CONCLUSIONS: The observed difference in PsqO(2) is clinically important because previous work suggests that comparable increases in tissue oxygenation reduced the risk of surgical infection from -8% to 2 to 3%. We conclude that mild intraoperative hypercapnia increased peripheral tissue oxygenation in healthy human subjects, which may improve resistance to surgical wound infections. 相似文献
63.
Karadeniz C Oguz A Ataoglu O Citak C Buyan N Pinarli G Ozkaya O Kapucu O 《Journal of nephrology》2002,15(5):597-600
Primary renal non-Hodgkin's lymphoma is very rare in childhood. A six-year-old boy presented with bilateral non-obstructive multinodular nephromegaly and renal failure. Percutaneous needle biopsy showed large-cell lymphoma. The patient was started on chemotherapy. A right nephrectomy was done when systemic hypertension developed in the presence of a non-functional right kidney. Histopathologic examination revealed focal lymphomatous infiltration and xanthogranulomatous pyelonephritis which is an atypical form of chronic renal infection. The case is discussed in relation to previons reports. 相似文献
64.
Apoptosis in the erectile tissues of diabetic and healthy rats 总被引:12,自引:0,他引:12
Alici B Gümüstas MK Ozkara H Akkus E Demirel G Yencilek F Hattat H 《BJU international》2000,85(3):326-329
OBJECTIVE: To compare the frequency of apoptosis in the erectile tissue of chronic diabetic and healthy rats. MATERIALS AND METHODS: Fourteen chronic diabetic and 10 healthy Sprague-Dawley rats were killed, their penises harvested and stored at -70 degrees C until staining and flow cytometric analysis for apoptosis. A cell suspension was obtained from the penile tissue by scraping the inside of the cavernosum with a scalpel and filtering through a mesh. Samples of the cell suspension (0.5 x 106 cells) were stained with Annexin V (an indicator of apoptosis) and propidium iodide (PI, which stains dead cells), incubated for 15 min at room temperature and analysed by flow cytometry. The DNA content was also analysed in each sample. RESULTS: In normal erectile tissue, a mean of 6.2% of cells were stained with Annexin V, while only 2.7% were stained with PI; DNA content analyses showed 7.5% were hypodiploid cells. In diabetic rats 19.5% of cells were stained with Annexin V and 5.2% with PI; 22.9% of cells were hypodiploid. CONCLUSION: The ratio of apoptotic cells in the erectile tissues of diabetic rats was significantly greater than in normal rats. The high rate of apoptosis in diabetic rats may play a role in the pathophysiology of erectile dysfunction. 相似文献
65.
Summary In a 43-year-old male cadaver the external pudendal vein ran an abnormal course in both inguinal regions. On each side the vein passed through the superficial inguinal ring, and after a short course in the canal pierced the inguinal ligament and drained into the femoral vein. The significance of this rare relation between the external pudendal vein and the inguinal canal is discussed from the embryological, surgical and diagnostic point of view. 相似文献
66.
Imaging the urinary tract in children has been mainly based on ultrasound (US) and intravenous pyelography (IVP), but these
imaging modalities rarely show ectopic insertion of the ureter and the condition is often under diagnosed due to unusual clinical
presentations. Recently newer magnetic resonance urography sequences have been developed that provide better delineation of
the urinary tract. We report a 3-year-old girl presenting continuous dribbling of urine in which magnetic resonance urography
revealed ectopic vaginal insertion of the ureter. 相似文献
67.
Elli M Söylemezoglu O Erbas D Bakkaloglu SA Buyan N Ozkaya O Hasanoglu E 《Pediatric nephrology (Berlin, Germany)》2005,20(11):1605-1609
Nitric oxide (NO) is an important messenger molecule with a wide range of actions in virtually all cell systems and organs. In kidneys it participates in glomerular and medullary hemodynamics, tubuloglomerular feed-back, renin secretion, and extracellular fluid balance. Although the role of NO in regulating renal function in adults is well-established, it has recently been suggested that NO has a more critical role in maintaining basal renal blood flow and glomerular filtration rate (GFR) in the developing kidney. NO is rapidly metabolized to the stable end products nitrite and nitrate, which are more slowly excreted into the urine. Thus these metabolites can be recommended as useful markers of endogenous NO synthase activity, despite limited data about age-related changes in in-vivo NO production. The aims of this study were to determine age-related normal reference values of serum and urinary NO metabolites and to assess the probable relationship between these metabolites and the GFR. Normal levels of NO end products in blood and urine of 296 healthy children (117 female, 179 male) between the ages of 0 and 16 were investigated, as was whether these values change with age. Serum and urinary nitrate levels did not differ according to sex. Serum nitrate levels are higher in younger children, especially in the newborn period, and decrease with age. Nitrate levels in urine are higher in younger children with a peak in infancy (1 month to 1 year) and decrease with age. It was demonstrated that this decrease in serum and urinary nitrate levels with age parallels the increase in GFR. In conclusion, urinary NO products may be an indirect marker of serum NO levels and NO might have an important regulatory function both in the maintenance of renal function and in the maturation of the developing kidneys. 相似文献
68.
A 26-year-old woman who had been treated for nonmetastatic gestational trophoblastic tumor with three courses of methotrexate
with folinic acid rescue and had been lost to follow up for 4 years was referred with the fractional curettage diagnosis of
choriocarcinoma that had been performed for abnormal vaginal bleeding. Her serum beta human chorionic gonadotropin (βhCG)
was 706,000 mIU/mL and there were multiple pulmonary metastatic foci. The uterus was 12 weeks pregnant-size and a 6×6-cm tumor
mass was seen within the anterior uterine wall at ultrasonography. Following total abdominal hysterectomy etoposide, methotrexate,
actinomycin-D, vincristine and cyclophosphamide (EMA/CO) regimen was given. Whole brain radiation of 30 Gy in 3 weeks for
brain metastasis, discovered in magnetic resonance imaging was given after the first course. Since serum βhCG levels plateaued
after three courses of chemotherapy and multiple pulmonary metastases persisted, treatment was shifted to etoposide, methotrexate,
actinomycin-D, etoposide, cisplatin (EMA/EP) regimen. She was in remission after three courses of chemotherapy. 相似文献
69.
Atasever T Ozkaya O Abamor E Söylemezoğlu O Buyan N Unlü M 《Nuclear medicine communications》2004,25(9):967-970
AIM: To evaluate the clinical usefulness of early cortical phase images in the diagnosis of acute pyelonephritis and to compare the measurements of differential renal function obtained by both 99mTc ethylene dicysteine (99mTc-EC) and 99mTc dimercaptosuccinic acid (99mTc-DMSA). METHODS: Forty-three children who had undergone both 99mTc-EC and 99mTc-DMSA studies within 5 days of acute infection were studied. Cortical images of 99mTc-EC were obtained by the sum of the renogram frames achieved between the first 60-120 s of the renogram study. DMSA and EC images were visually interpreted using four points of semiquantitative ratings: 0, normal; 1, mild hypoactivity; 2, moderate hypoactivity with partial loss of margins; 3, marked hypoactivity with loss of cortical margins. Values for the differential renal function were obtained for both studies. RESULTS: DMSA detected a total of 109 lesions in 36 patients and EC detected 90 lesions with a sensitivity of 82.5%. 99mTc-EC successfully detected moderate-to-severe cortical lesions but was less effective with mild lesions (sensitivity 60%). Bland-Altman analysis demonstrated good agreement among the results for differential renal function (95% CI -0.26 to 0.96). CONCLUSION: 99mTc-EC early phase images detected most of the cortical lesions. Its sensitivity depends on the severity of the lesions. EC provided reliable information in the estimation of differential renal function. 相似文献
70.