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31.
Renal scarring due to pyelonephritis was shown to improve in rats given vitamin A. We evaluated the effect of vitamin A in a renal ablation nephropathy model. Four groups, each including 7 rats with 5/6 nephrectomy, were formed: group I (no vitamin A), group II (60 kIU vitamin A), group III (120 kIU vitamin A), and group IV (180 kIU vitamin A). Four sham-operated rats comprised the control group. After 6 weeks of 5/6 nephrectomy, the rats were sacrificed and serum creatinine, vitamin A, and β-carotene levels were determined in addition to histopathological evaluation of the remnant kidneys. The tubulointerstitial and glomerular changes were graded as ”0–3” and ”0–5” respectively, in accordance with the severity of the lesions. Tubulointerstitial score (TIS), mean glomerulosclerosis score (MGS, arithmetical mean of the sclerosis scores of 100 glomeruli), and severity of glomerulosclerosis index (SGI, ratio of the number of glomeruli with grade ≥3 sclerosis to the total number of glomeruli examined) were calculated for each rat. Serum creatinine levels were higher in the study groups than the control rats (P<0.05), but there was no significant difference between the study groups (although the levels increased as the dose of vitamin A increased). Serum vitamin A levels were significantly higher in the groups given vitamin A than the control rats and group I (P<0.05). In addition, serum vitamin A levels increased significantly in parallel to increasing doses of vitamin A (P<0.05). Serum β-carotene levels did not differ between the groups, except for group II, which had lower levels than controls (P=0.01). MGS and SGI were significantly higher in the study groups than control rats (P<0.05), but did not differ between the study groups. Study and control rats were not different with respect to TIS, but there was a difference between the control group and group III (P=0.04). Group II had the lowest MGS, SGI, and TIS scores among the study groups. When all the rats were considered together, vitamin A levels did not correlate with the MGS and SGI, but correlated positively with the TIS (r=0.391, P=0.027). β-Carotene levels also did not correlate with the MGS, SGI, and TIS. In conclusion, vitamin A administration did not significantly affect the clinical and pathological course of renal ablation nephropathy in rats. Furthermore, higher doses of vitamin A might even damage renal tissue. Received: 14 June 1999 / Revised: 2 December 1999 / Accepted: 2 December 1999  相似文献   
32.
We report our success with somatostatin and propranolol to treat small-for-size syndrome that occurred despite splenic artery ligation. A 48-year-old woman with cirrhosis due to autoimmune hepatitis underwent living-donor liver transplant; her graft-to-body weight ratio of the right lobe was 0.91%. After arterial reperfusion, portal pressure and flow were 24 cm H20 and 2.22 L/min (ie, 360 mL/100g graft/min), respectively. Following splenic artery ligation, the portal pressure decreased to 16 cm H20 and portal flow to 1.74 L/min (ie, 282 mL/100g graft/min). On the second postoperative day, small-for-size syndrome was diagnosed based on the marked prolongation of prothrombin time (international normalized ratio, 4.4), hyperbilirubinemia (359.1 micromol/L), rapid escalation of transaminases (alanine aminotransferase 2488 U/L, aspartate aminotransferase 1075 U/L) and very high portal flow rate (> 90 cm/sec). Oral propranolol (40 mg/day b.i.d.) and somatostatin infusion (250-microgram bolus followed by perfusion at a rate of 250 microgram/h for 5 days) were started. Prothrombin time and transaminase levels began to decrease the following day, although the bilirubin level increased to 495.9 micromol/L before returning to normal. The patient was discharged in excellent health 5 weeks after surgery. Despite reduction of portal pressure by splenic artery ligation, small-for-size syndrome may develop in patients with persistent high portal flow. To the best of our knowledge, this is the first report of the successful treatment of small-for-size syndrome by somatostatin and propranolol in the clinical setting.  相似文献   
33.
BACKGROUND: Acute liver failure (ALF) carries a high mortality unless urgent orthotopic liver transplantation (OLT) is performed on time. Live donors are utilized to treat this irreversible condition first in pediatric cases and then in adults. Herein, we aimed to report our experience with live donors for ALF in a country of a deceased donor organ donation rate is only 1.5 per million people. METHODS: Among the 245 live donor liver transplantations (LDLT) performed from June 1999 to December 2005, 14 of them (6%) were performed for ALF in 8 pediatric and 6 adult cases. Right lobes were harvested for the adult cases whereas left lateral segments were harvested for pediatric cases, except one child transplanted with a right lobe graft. The etiology of the disease was; acute hepatitis B in four cases, hepatitis A in three cases, Wilson disease two cases, autoimmune hepatitis in two cases, and was unknown in three cases. RESULTS: Three-year graft and patient survival is 79% for these series. Five of the six adult patients and six of the eight pediatric cases survived after transplantation. There was not any donor mortality or major morbidity. CONCLUSIONS: LDLT offers a safe and effective modality of treatment for ALF for both pediatric and adult patients to overcome the problem of organ shortage especially in countries where the chance of receiving an organ from a deceased donor is low.  相似文献   
34.
BACKGROUND: Complicated hydatid cyst of the thorax is important to the clinical approaches and treatment methods in hydatid disease. The aim of this study was to evaluate the problems of complicated pulmonary hydatid cyst, including choice of surgical methods, diagnostic clues and to discuss the inherent risks of medical therapy and the delay of surgical treatment in pulmonary hydatid disease. METHODS: Between 2002 and 2006, 40 operations were carried out in 37 patients whose diagnoses were complicated hydatid cyst. The surgical approach was a posterolateral thoracotomy in all patients; a phrenotomy in two patients and a thoracoabdominal approach in one patient and two-stage bilateral thoracotomy in four patients. The preferred surgical treatment procedure was cystotomy and modified capitonnage, which was carried out in 26 patients (70%). Other procedures included a cystotomy in five (14%) and decortication in six (16%) patients. Segmentectomy was carried out in 1 (3%), and wedge resection in four patients (11%). RESULTS: In 25 patients (67.5%), there were single hydatid cysts; whereas 12 patients (32.5%) had multiple cysts. Eleven patients had preoperative hydatid cyst history. Iatrogenic rupture of an intact hydatid cyst occurred in three patients. Extrathoracic involvement was apparent in 10 patients (27%). Intrathoracic but extrapulmonary involvement was apparent in six patients (16%). The morbidity ratio was 5%; there was prolonged air leak and atelectasis in one patient each. The mortality ratio was 3% (one patient). The average hospitalization duration for all patients was 5.7 days (range, 3-17 days). The mean follow up was 18.4 months with no recurrence. CONCLUSION: Complicated hydatid cyst may have different clinical manifestations and may present radiologically as a primary lung tumour. In patients with suspicious lung masses owing to endemic area, history of a hydatid cyst or contralateral or extrathoracic hydatid cyst involvement at the same time should indicate a complicated pulmonary hydatid cyst. Preoperative anthelmintic therapy must be avoided owing to the risk of perforation. Treatment of a complicated hydatid cyst differs from that of an intact hydatid cyst. Anatomic resection may be necessary owing to destroyed lung tissue secondary to suppuration from a hydatid cyst; however, parenchymal preserving surgery is preferable in an uncomplicated hydatid cyst. A modified capitonnage method is recommended for complicated hydatid cyst treatment as it has a low morbidity rate.  相似文献   
35.
Transcaval extension of the thymoma to the right atrium has very rarely been reported, and cardiopulmonary bypass is recommended for successful resection. An invasive thymoma with intravascular invasion of the superior vena cava, and the left innominate vein extending into the right atrium was presented. Intra-atrial extension was resected through a transient external shunt from the inferior vena cava to the main pulmonary artery. We discussed the feasibility of this surgical technique and possible advantages of cardiopulmonary bypass avoidance.  相似文献   
36.
ABSTRACT: BACKGROUND: There is accumulating evidence for an increased cardiovascular burden in inflammatory arthritis, but the true magnitude of this cardiovascular burden is still debated. We sought to determine the prevalence rate of non-fatal cardiovascular disease (CVD) in inflammatory arthritis, diabetes mellitus and osteoarthritis (non-systemic inflammatory comparator) compared to controls, in primary care. METHODS: Data on CVD morbidity (ICPC codes K75 (myocardial infarction), K89 (transient ischemic attack), and/or K90 (stroke/cerebrovascular accident)) from patients with inflammatory arthritis (n = 1,518), diabetes mellitus (n = 11,959), osteoarthritis (n = 4,040) and controls (n = 158,439) were used from the Netherlands Information Network of General Practice (LINH), a large nationally representative primary care based cohort. Data were analyzed using multi-level logistic regression analyses and corrected for age, gender, hypercholesterolemia and hypertension. RESULTS: CVD prevalence rates were significantly higher in inflammatory arthritis, diabetes mellitus and osteoarthritis compared with controls. These results attenuated - especially in diabetes mellitus - but remained statistically significant after adjustment for age, gender, hypertension and hypercholesterolemia for inflammatory arthritis (OR = 1.5 (1.2-1.9)) and diabetes mellitus (OR = 1.3 (1.2-1.4)). The association between osteoarthritis and CVD reversed after adjustment (OR = 0.8 (0.7-1.0)). CONCLUSIONS: These results confirm an increased prevalence rate of CVD in inflammatory arthritis to levels resembling diabetes mellitus. By contrast, lack of excess CVD in osteoarthritis further suggests that the systemic inflammatory load is critical to the CVD burden in inflammatory arthritis.  相似文献   
37.

Purpose

To evaluate the possible effects of citrate replacement on the efficacy of shockwave lithotripsy (SWL) in the management of kidney stones in cases with hypocitraturia.

Methods

Forty hypocitraturic cases with renal pelvic stones were randomized into two groups; while citrate replacement has been done before and at the time of SWL in Study Group I (n: 20), SWL was performed without any additional specific management for hypocitraturia in Study Group II (n: 20). Twenty normocitraturic cases were also chosen as the control group (Group III). Data of the patients were evaluated comparatively.

Results

Patient, stone, and urinary pH characteristics of the groups were similar. Pre-SWL urinary citrate levels were 0.71 (0.1?C1.3), 0.86 (0.1?C1.4), and 3.12 (1.8?C4.4)?mmol/24?h in Group I, II, and III, respectively. Urinary citrate value increased from 0.71 (0.1?C1.3) to 1.96 (1.6?C4.1)?mmol/24?h following replacement therapy (before and at the time of SWL) in Group I. Mean number of SW (p?=?0.461), rate of stone-street formation (p?=?0.146), and Double-J placement (p?=?0.291) were similar in Group I and Group II. While the mean number of SWL sessions (2.27?±?0.71 in Group I vs. 2.94?±?0.59 in Group II; p?=?0.027), and time to stone-free status [29.1 (16?C47) days in Group I vs. 38.4(21?C63) days in Group II; p?=?0.043], was significantly different between study groups, these parameters were found similar between Group I and Group III.

Conclusions

In our study, the patients with hypocitraturia, who did receive replacement therapy, tended to require lower number of SWL sessions and became stone free in a shorter period than the others who underwent SWL without any specific management of hypocitraturia.  相似文献   
38.
Kaya RA  Türkmenoğlu O  Dalkiliç T  Aydin Y 《Neurosurgery》2003,53(5):1230-3; discussion 1233-4
OBJECTIVE AND IMPORTANCE: A spinal cord tumor occurring in association with Klippel-Feil syndrome is quite rare. The removal of an anteriorly located spinal cord tumor at the level of block vertebrae creates a surgical challenge. CLINICAL PRESENTATION: A case of an intradural extramedullary dermoid cyst located anterior to the spinal cord and a syringomyelic cavity at the level of block vertebrae in a 43-year-old woman with Klippel-Feil syndrome is presented. She experienced pain and numbness in both shoulders and in her neck, and she had a slight weakness in both arms before the operation. Her weakness and the clinical symptoms completely disappeared after the operation, and the resolution of the syringomyelic cavity was observed at control magnetic resonance imaging. INTERVENTION: An anterior approach creating a fenestra corpectomy to the block vertebrae was performed, and the tumor was removed totally. No fusion or fixation was performed. CONCLUSION: To our knowledge, this is the first report of an anteriorly located intradural extramedullary cervical spine tumor in association with Klippel-Feil syndrome treated with this surgical technique. A three-dimensional computed tomographic control scan obtained 1 year after the operation did not show any instability.  相似文献   
39.
OBJECTIVES: We tested the hypothesis that mastoid volume buffers the rate of change in middle ear pressure caused by transmucosal, inert gas exchange. STUDY DESIGN: Twelve monkeys were randomly assigned to group 1 or group 2. Right ears of group 1 had sham surgery and of group 2 had obstruction of the mastoid antrum. Before and after surgery, the time constant for transmucosal N(2)O exchange was estimated from N(2)O breathing experiments. The hypothesis predicts that the postoperative time constant measured for right ears of group 2 but not group 1 is greater than that measured before surgery. RESULTS: Mastoid antrum block significantly decreased right middle ear volume but did not affect the time constant for transmucosal N(2)O exchange. CONCLUSION: A mastoid gas-reserve function is not supported by the experimental data. SIGNIFICANCE: These results for monkeys and the theory developed to explain the effect of mastoid volume on transmucosal inert gas exchange suggest that the results for previous experiments in humans interpreted as evidencing a mastoid gas-reserve function are consistent with alternative explanations.  相似文献   
40.
Dynamic computed tomography in solitary pulmonary nodules   总被引:1,自引:0,他引:1  
OBJECTIVE: To evaluate the utility of dynamic computed tomography (CT) imaging in the management of solitary pulmonary nodules. METHODS: We examined solitary pulmonary nodules in 45 patients. The nodules included in the study were solid, homogenous, and spherical or oval-shaped in precontrast images. Nodules that had calcification or fat density were excluded from the study. We were not able to obtain clinical or pathological diagnosis of the nodules in 23 patients, and we excluded these patients from statistical analysis. Patients were examined with 2-mm collimation and 1-mm reconstruction interval. Computed tomography examinations were done before and after injection of contrast material. Computed tomography scans of the nodule were obtained in the first, second, third, fourth, and fifth minutes after contrast injection. RESULTS: The malignancy prevalence was 40%. The mean enhancement of malignant nodules were significantly higher than the benign ones. Also, the peak attenuation value obtained after the administration of contrast material was 82.44 +/- 19.56 HU in malignant lesions and 54 +/- 23.10 HU in benign ones, with statistical significance (P = 0.006). Using enhancement values greater than 15 HU as a threshold for malignancy, the calculated sensitivity, specificity, positive and negative predictive values, and accuracy of the dynamic CT examination were 100%, 69.2%, 69.2%, 100%, and 81%, respectively. CONCLUSION: Dynamic CT imaging demonstrates significantly greater enhancement in malignant nodules than in benign ones. Lung nodule enhancement of 15 HU or less strongly indicates benignity.  相似文献   
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