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1.
Image-directed color Doppler ultrasonography (ICDUS) studies of 86 patients with superficial solid masses yielded significantly lower resistive index (RI) values in acute inflammatory lesions, but no significant difference between the maximum systolic flow velocities (S) of the patient groups with malignant, benign, and acute inflammatory lesions. When analyzed separately, the malignant soft-tissue tumor subgroup was shown to have significantly higher mean RI compared to that of the malignant node subgroup. We conclude that RI may be useful in the differentiation of acute inflammatory masses from other pathological entities. Malignant soft-tissue tumors, especially sarcomas, may have different Doppler features from those of carcinomatous tumors. © 1995 John Wiley & Sons, Inc.  相似文献   
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In patients with coronary heart disease oxidizability of lipids during Cu2+-induced oxidation of blood plasma inversely correlated with fibrinogen content. A positive correlation was found between the amount of lipid peroxidation products in the plasma from these patients and fibrinogen content. The increase in fibrinogen content was associated with high levels of total lipids and triglycerides and low concentration of high-density lipoprotein cholesterol. In vitro experiments demonstrated that fibrinogen reduces oxidizability of blood plasma. Our results suggest that the decrease in lipid oxidizability at high concentration of fibrinogen in patients with coronary heart disease is related to predominant oxidation of fibrinogen and its competition with plasma lipids during Cu2+-induced oxidation.  相似文献   
4.
The kinetics of copper-induced oxidation of lipids in serum low-density lipoproteins from healthy subjects and patients with ischemic heart disease and documented coronary atherosclerosis is studied. After a 4-h incubation with 40 μM CuSO4, the oxidizability of patients' lipoproteins is higher, judging from the contents of diene conjugates and oxidation products reacting with thiobarbituric acid. Intergroup differences in the kinetics of the diene conjugate formation are revealed. Statistical analysis shows that in all studied individuals there is no relationship between the oxidizability of low-density lipoproteins and the cholesterol content in lipoproteins and serum. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 122, No. 7, pp. 32–36, July, 1996  相似文献   
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Objective

This study explores the potential use of drones in searching for and locating victims and of motorized transportation of search and rescue providers in a mountain environment using a simulation model.

Methods

This prospective randomized simulation study was performed in order to compare two different search and rescue techniques in searching for an unconscious victim on snow-covered ground. In the control arm, the Classical Line Search Technique (CLT) was used, in which the search is performed on foot and the victim is reached on foot. In the intervention arm, the Drone-snowmobile Technique (DST) was used, the search being performed by drone and the victim reached by snowmobile. The primary outcome of the study was the comparison of the two search and rescue techniques in terms of first human contact time.

Results

Twenty search and rescue operations were conducted in this study. Median time to arrival at the mannequin was 57.3 min for CLT, compared to 8.9 min for DST. The median value of the total searched area was 88,322.0 m2 for CLT and 228,613.0 m2 for DST. The median area searched per minute was 1489.6 m2 for CLT and 32,979.9 m2 for DST (p < 0.01 for all comparisons).

Conclusions

In conclusion, a wider area can be searched faster by drone using DST compared to the classical technique, and the victim can be located faster and reached earlier with rescuers transported by snowmobile.  相似文献   
7.
Surgical treatment of axillary artery aneurysm   总被引:2,自引:0,他引:2  
Aneurysms of the axillary artery are rare and dangerous lesions that threaten the upper extremities with vascular and neurologic compromise. Most can be treated effectively with surgical excision and vascular grafting. We retrospectively assessed 4 axillary artery aneurysms upon which we operated from February 1998 through March 2004. Three patients were admitted to our clinic for symptomatic axillary masses. The remaining patient was transported to our clinic emergently due to massive hemorrhage of an enlarging axillary mass that occurred during biopsy of the mass at another hospital. In this patient, the ruptured axillary artery aneurysm was diagnosed by means of emergent upper-extremity selective angiography. All patients were treated surgically by means of aneurysmectomy and graft interpositioning--with polytetrafluoroethylene grafts in 2 patients and saphenous vein grafts in the other 2. Surgical treatment of axillary artery aneurysms is of importance in avoiding thromboembolism and ischemia, which in turn can lead to gangrene and amputation of the affected extremity. For this reason, operative management of such cases should not be delayed.  相似文献   
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Background and Aim:

Ischemia/reperfusion (I/R) injury in the liver occurs after a prolonged period of ischemia followed by restoration of hepatic blood perfusion. During the surgery of abdominal aorta, I/R injury causes damage to lower extremities and many organs, especially liver. The antioxidant and tumor necrosis factor-alpha (TNF-α) suppression effects of topiramate (TPM) have been reported in several studies. We evaluated the potential protective effect of TPM on cellular damage in liver tissue during I/R injury.

Materials and Methods:

Thirty male Wistar albino rats were divided into three groups: Control, I/R, and I/R plus TPM (I/R + TPM) groups. Laparotomy without I/R injury was performed in the control group. After laparotomy, cross-ligation of infrarenal abdominal aorta was applied for 2 h in I/R groups that was followed by 2 h of reperfusion. TPM (100 mg/kg/day) was orally administrated to the animals in the I/R + TPM group for seven consecutive days before I/R procedure.

Results:

The I/R group''s TNF-α and interleukin-6 (IL-6) levels were significantly higher than those of the control (P = 0.010; P = 0.002) and I/R + TPM groups (P = 0.010; P = 0.002, respectively). Asymmetric dimethyl arginine (ADMA) levels of I/R group were higher than the control (P = 0.015) and I/R + TPM groups. I/R caused serious histopathological damage to liver tissue; however, TPM led to very low histopathological changes.

Conclusion:

Our data demonstrated that TPM treatment prominently decreases the severity of liver I/R injury. TPM pretreatment may have preventive effects on liver injury via I/R during intra-abdominal surgery.  相似文献   
10.

Objective

To determine whether some clinical parameters can be used to predict the hemorrhage and whether the relationship between these clinical variables and the grades of hemorrhage is linear.

Methods

A total of 230 premature infants, born at a gestational age less than 34 weeks were retrospectively reviewed. Germinal matrix-intraventricular hemorrhage (GM-IVH), the grade of the hemorrhage, and clinical data were assessed with a checklist. Variables were analyzed by using Mann Whitney U and Fisher’s exact tests and then multiple logistic regression analysis was used to evaluate the independent risk factors.

Findings

Resuscitation, gestational age, hypotension, multiple birth, and birth weight were found to be independent risk factors. We determined non-linear relationship between the grades of hemorrhage and the clinical parameters. But when we classified hemorrhages as grade 1, grade 2-3 and grade 4, the relationships were found linear.

Conclusion

Premature infants who had resuscitation, low gestational age, hypotension, multiple birth, and low birth weight are more likely to have GM-IVH. The relationship between the clinical variables and the grades of GM-IVH does not seem to be linear.  相似文献   
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