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This study describes the influence of isocalorically fed diets (containing different amounts of fat) on tumor incidence and parameters of fat metabolism in female Sprague-Dawley rats. Comparisons are made between rats induced with methylnitrosourea (25 mg/kg body wt) and untreated controls (Group I). The animals received either control diets (3.9% fat by weight, Groups I and II) or fat-enriched diets (10.7%, Group III; 15.6%, Group IV; 21.4%, Group V) over a period of 180 days. At the termination of the experiment, intake of the diet containing 10.7% fat by weight (24% fat per total calories) was associated with the highest tumor incidence. Comparing the different diets, liver lipid concentrations in the individual groups increased with increasing dietary fat, whereas the total lipid in plasma decreased. During the feeding period, total lipid of the liver and plasma, and plasma cholesterol, increased in all groups, but triglycerides of plasma decreased. However, when plasma cholesterol and triglycerides were calculated as a relative amount of total lipid in plasma, cholesterol was found to be significantly decreased in Groups III and IV, and triglycerides were increased in Group III but decreased significantly in Groups I, II, and V at the end of the experiment.  相似文献   
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1. Canine jugular and femoral veins were studied to determine the possible importance of thromboxane (TXA2) and prostaglandin endoperoxides (prostaglandin H2, PGH2) in mediating bradykinin(BK)-induced contraction. 2. Isolated vein rings incubated in modified Krebs solution contracted to TXA2/PGH2 analogs SQ26655 and U44069 with potency of contraction exceeding that for BK. The potency ranking for both veins was SQ26655 greater than U44069 greater than BK greater than PGF2 alpha greater than TXB2 much greater than PGD2. 3. The cyclo-oxygenase inhibitors indomethacin (3 x 10(-7) M) and flufenamic acid (10(-5) M) reduced BK contractions without affecting those induced by noradrenaline (NA). 4. TXA2/PGH2 receptor antagonists SQ29548 (10(-8) M) and BM13177 (10(-6) M) strongly inhibited BK-induced tension. The action of antagonists was reversible with negligible influence on NA-elicited contraction. Selective removal of endothelium had no effect on BK-induced contraction or the action of the antagonists. 5. The thromboxane synthase inhibitors dazoxiben (10(-4) M) and CGS 12970 (10(-5) M) had no significant inhibitory effect on BK-induced tension. 6. These results suggest that in canine jugular and femoral vein, the action of BK is largely dependent upon stimulation of the cyclo-oxygenase pathway to produce PGH2 and possibly TXA2, which can activate a smooth muscle TXA2/PGH2 receptor to elicit vasoconstriction.  相似文献   
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BACKGROUND: Superficial lymphatic malformations are predominantly developmental malformations of infancy, but they may arise at any age. OBJECTIVE: To describe a patient with a late-onset superficial lymphatic malformation. METHODS: Case report and literature review. RESULTS: A 53-year-old woman was evaluated for a colored lesion that developed spontaneously on the anterior abdominal wall. The lesion was treated by surgical excision. Findings on histopathologic examination of the specimen were consistent with superficial lymphatic malformation. There was no recurrence of the lesion at 4 months after the operation. CONCLUSION: Superficial lymphatic malformations can develop in adults spontaneously without the presence of any predisposing condition. Because the majority of such late-onset malformations reported in the literature are localized lesions similar to the one in our patient, surgical removal with inclusion of subcutaneous tissue usually results in cure without recurrence.  相似文献   
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Intravenous Pyogenic Granuloma of the Hand   总被引:1,自引:0,他引:1  
BACKGROUND: Intravenous pyogenic granuloma is the intravasal counterpart of cutaneous pyogenic granuloma. This rare, benign lesion appears clinically as a subcutaneous nodule usually located in the upper extremity or neck in middle-aged people. It is hard to make an exact diagnosis on clinical basis, and there is a risk of recurrence because of undertreatment. OBJECTIVE: To report a case of an intravenous pyogenic granuloma located in the hand and to describe the clinical and histopathologic features of this rare vascular tumor. METHODS: An operation was performed on a 58-year-old female who presented with a small, painless mass in the right palm, and the pathologic examination revealed an intravenous pyogenic granuloma. CONCLUSION: This rare lesion should be differentiated from a regular pyogenic granuloma and should be excised with the vein segment to avoid recurrence.  相似文献   
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Background: The aim of this study was to investigate the postoperative hemodynamic effects of nitroglycerin inhalation on patients with pulmonary hypertension undergoing mitral valve replacement surgery.

Methods: Twenty patients who underwent mitral valve replacement surgery were included in the study. In the surgical intensive care unit, at T0 (before the inhalation of nitroglycerin), basal systemic and pulmonary hemodynamics were recorded. Then, 2.5 [mu]g [middle dot] kg-1 [middle dot] min-1 nitroglycerin liquid nebulized by a 2-l gas flow of 40% oxygen and air mixture was administered to the patients who were diagnosed as having pulmonary hypertension (mean pulmonary arterial pressures > 25 mmHg). The same parameters were measured at the first (T1), third (T2), and fifth (T3) hours after the beginning of this treatment and 1 h after the end of nitroglycerin inhalation (T4).

Results: There were no statistically significant differences at T0, T1, T2, T3, or T4 with respect to heart rate, mean arterial pressure, systemic vascular resistance, cardiac index, mixed venous oxygen saturation, arteriovenous oxygen content difference, or arterial carbon dioxide tension. However, mean pulmonary artery pressure, pulmonary vascular resistance, and intrapulmonary shunt fraction were significantly lower, and the arterial oxygen tension/fraction of inspired oxygen ratio was higher at T1, T2, and T3 when compared to that of T0 and T4.  相似文献   

9.
Abdominal and pelvic operations at Departments of Obstetrics and Gynaecology, and General Surgery play an important role in ureteral, bladder and rarely urethral injuries. Fifty-nine patients with iatrogenic ureteral, bladder and urethral injuries were treated at the Department of Urology, Atatürk University Research Hospital, between 1985 and 1995. These injuries were urinary vaginal fistulas in 43 patients (vesicovaginal 33, ureterovaginal 7, urethrovaginal 2 and vesicovaginal plus urethrovaginal 1), ureteric ligation in 9, bladder laceration in 7. These injuries were treated by different methods. All patients were followed up by intravenous urography (IVU) and urine culture three months later. It must be borne in mind that iatrogenic urinary tract injuries are not rare. Bladder and ureteral catheterization must be performed to prevent these complications.  相似文献   
10.
DNA methods have resulted in improved renal allograft survival rates in cadaveric renal transplantation. This paper describes the impact of DNA typing by PCR-SSP on a living-related renal transplant (LRRT) programme. It evaluates error rates in serology, acute rejections, graft function and survival rates between the two typing methods. Serological typing was carried out on CTS 120 antisera Class 1, 60 antisera Class 2, 72 antisera Terasaki Class 1 and 72 antisera Class 2 antigens. Low-resolution PCR-SSP typing was carried out by 24 primers for HLA-A, 48 for HLA-B and 24 for HLA-DR. Of the 585 transplants: 159 (Group I) were serology based; 172 were serology and PCR-SSP based for HLA-DR (Group II); and 254 were serology and PCR-SSP based for HLA-A and -B, and only PCR-SSP based for HLA-DR (Group III). Error rates in serology compared with PCR-SSP were 24% for HLA-A, 16% for HLA-B and 35% for HLA-DR. Acute rejections were 39%, 30% 26% in Groups I, II and III, respectively ( P= 0.02). Graft function of serum creatinine <1.5 mg/dl at 1 year was found in 26% of the Group I patients compared with 48% of those in Group III ( P <0.0001). One- and 3-year graft survival was 93% and 87% for Group II compared with 81% and 69% for Group I, respectively ( P= 0.0001). Matching by this combination of serology and PCR-SSP is not only economical for a developing country but also improves graft survival by 12% and 18% at 1 and 3 years, respectively.  相似文献   
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