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91.

Aim

Extended liver resection has increased during the last decades. However, hepatic hemodynamic changes after resection and the consequent complications like post hepatectomy liver failure are still a challenging issue. The aim of this study was to systematically evaluate the role of stepwise liver resection on hepatic hemodynamic changes.

Methods

To evaluate this effect we performed 25, 50, and 75 % sequential liver resections in 10 pigs. Before and after each resection, the hepatic artery flow and portal vein flow in relation to the remnant liver volume (RLV) as well as hepatic vascular pressures were measured and compared between the groups.

Results

Following sequential liver resection, the hepatic artery flow /100 g decreases and the portal vein flow increases up to 17 and 167 % following extended liver resection (75 %), respectively. Also, during stepwise liver resection, the portal vein pressure increases gradually up to 33 % following extended hepatectomy (75 %).

Conclusion

Sequential decrease in the RLV decreases the hepatic artery flow /100 g and increases the portal vein flow /100 g and portal vein pressure. As the consequence, the liver goes under more poor-oxygenated blood supply and higher pressure. This may be one of the most important mechanisms of the post hepatectomy liver failure in case of extended liver resection.
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Psychiatric Quarterly - Our study systematically reviews articles about the prevalence of Post-traumatic Stress Disorder (PTSD) among children and adolescents, aiming to evaluate its prevalence...  相似文献   
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96.
Infection with subsequent wound breakdown and soft tissue deficit represents the most devastating complication after total knee arthroplasty. Although microsurgical reconstruction is increasingly being performed in this setting, several factors may preclude its use. We present a case of a 52-year-old female patient who presented with a complex right anterior knee wound resulting from a complicated clinical course following total knee arthroplasty. Initial reconstructive efforts included coverage with a superiorly based fasciocutaneous thigh flap as well as a medial gastrocnemius flap. Persistence of infection and necrosis of the distal aspect of the fasciocutaneous flap eventually required salvage by means of a vastus lateralis turnover muscle flap augmented by a lateral gastrocnemius muscle flap. The combination of these two fairly straightforward muscle flaps provided stable wound coverage with well-vascularized tissue without the use of sophisticated microsurgical expertise. Level of Evidence: V, therapeutic study  相似文献   
97.
The main aim of this study was to assay the testicular H2S levels in the varicocele rat model and then to investigate the protective effects of NaHS on morphometric changes, sperm parameters, oxidative stress and apoptosis markers in rat's testis. D,L-propargylglycine (PAG) was administrated to show the effects of cystathionine γ-lyase enzyme (CSE) inhibition in the varicocele. Rats were assigned to four groups: (a) Sham, (b) varicocele, (c) varicocele + PAG and (d) varicocele + NaHS. Animals in varicocele + NaHS group received 30 µmol/L NaHS in drinking water for 56 days. In the varicocele + PAG group, animals received PAG 19 mg/kg twice a week. Morphometric assessment, oxidative stress markers, testicular H2S levels, sperm parameters, TUNEL assay and expression of Bax/Bcl2 were evaluated at the end of experiment. Testicular H2S levels were significantly decreased in varicocele group. NaHS significantly improved sperm parameters, morphometric characteristics and oxidative stress compared to varicocele group. Oxidative stress status deteriorated in the PAG group compared to the varicocele group. This study showed that a low testicular H2S level might play a critical role in male infertility. Thus, NaHS administration may be a promising treatment strategy for male infertility in varicocele. In addition, CSE may not be the only important enzyme in testicular H2S production.  相似文献   
98.
Testicular torsion is a serious urological disease leading to testicular damage. This study aimed to assess the effect of minocycline on testicular ischaemia/reperfusion (I/R) injury caused by testicular torsion/detorsion. Male adult Wistar rats (n = 32) were assigned into four groups of sham, I/R, I/R + minocycline and minocycline. I/R injury was induced by two sets of surgical operations, including the rotation of the left testis (720°, counterclockwise), followed by detorsion after 4 hr. The administration of minocycline was carried out 30 min before detorsion and then continued for 8 weeks. At the end of the 8th week, rats were killed and sampling was done. Johnson's score, the height of seminiferous tubule epithelium, the mean seminiferous tubule diameter, as well as biochemical parameters, SOD, GPx and CAT, were significantly enhanced in the I/R + minocycline group compared with the I/R group. The administration of minocycline led to a marked decrease in expression levels of Caspase-3, Bax, IL-1β and TNF-α genes, and a remarkable increase in expression levels of Bcl-2, 3β-HSD and 17β-HSD3 genes compared with the I/R group. Administration of minocycline could also reduce the rate of germ cell apoptosis (TUNEL staining). Hence, minocycline was useful in the management of testicular torsion/detorsion.  相似文献   
99.
BACKGROUND: Breast cancer patients with pulmonary lesions are often assumed to have metastatic disease and treated palliatively. We evaluated the proportion of these patients who actually have primary lung tumor (PLT) and assessed their outcome. METHODS: We performed a 10-year retrospective review of the cancer registry in a community hospital system. RESULTS: Among 54 breast cancer patients with pulmonary nodules, biopsy was pursued in 30. Although metastatic breast cancer (MBC) was presumed in 24, biopsy showed MBC in 9 patients and PLT in 21. The two groups differed in age, stage, breast tumor size, nodal involvement, and estrogen receptor (ER) positivity. However, no variable excluded the possibility of PLT. Of those with PLT, 11 had early-stage lung disease; 9 underwent curative resection. CONCLUSIONS: Women with breast cancer and 1 or more pulmonary lesions without evidence of other metastatic disease require work-up of pulmonary lesions. Aggressive evaluation can afford treatment of lung cancer and impact survival.  相似文献   
100.
Osteoporosis is a major public health problem in the Western countries and is projected to have a similar impact in the Middle East. It has been suggested that peak bone mineral density (BMD), a major determinant of osteoporotic fractures later in life, may be lower in this part of the world compared with the Western world. The purpose of the Iranian Multicenter Osteoporosis Study was to determine peak bone mass in a randomly chosen sample of healthy Iranian subjects. A total of 5201 participants (2340 males, mean age 42.7+/-13.8) were recruited based on randomized clustered sampling from all regions of five major cities across the country. In women, peak lumbar BMD (1.182+/-0.127 g/cm2) occurred in the 29- to 33-yr age group, whereas peak total femur BMD (1.006+/-0.126 g/cm2) occurred in the 32- to 36-yr age group. In men, peak lumbar BMD (1.181+/-0.153 g/cm2) and femoral BMD (1.096+/-0.159 g/cm2) both occurred in the 20- to 24-yr age group. When standardized to mg/cm2 units using established formulas, Iranian peak bone mass values are comparable with that of Western countries and are generally higher than that of Eastern Asian and Middle Eastern countries.  相似文献   
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