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1.
To determine whether pulsatile hypothermic perfusion with University of Wisconsin preservation solution is superior to topical cooling as a method for the preservation of amputated limbs, six pairs of amputated canine limbs were preserved for twelve to fifteen hours. One limb of each pair was subjected to topical cooling and the other, to pulsatile hypothermic perfusion with University of Wisconsin solution. The bioenergetic status of the limbs was monitored by 31phosphorus magnetic-resonance spectroscopy, and histological evaluation was performed to assess ischemic changes in the preserved tissue. The pH and tissue levels of adenosine triphosphate declined three times more slowly in the limbs that were preserved by pulsatile hypothermic perfusion than in the topically cooled limbs. Consistent with these findings, the perfused limbs also had less histological evidence of ischemic injury. The data from this in vitro study show that pulsatile hypothermic perfusion with University of Wisconsin solution, in combination with an optimum degree of topical cooling, is superior to topical cooling alone as a method of preserving the bioenergetic status of amputated limbs.  相似文献   
2.
There is experimental evidence that a portion of follicle-stimulating hormone (FSH) secretion is independent of hypothalamic influences. A 29 year old woman with familial pure gonadal dysgenesis developed myelodysplastic syndrome. Endocrine investigations showed discrepancy between serum FSH and luteinizing hormone (LH) levels. FSH levels remained elevated while LH levels decreased. The FSH to LH ratio was 10 (normal 2-2.5). The fall in LH is likely to be due to factor(s) involved directly and specifically in LH synthesis and release. Exogenous LH releasing hormone administration as well as hormonal replacement treatment increased LH levels. The FSH to LH ratio decreased to 7. This case supports the hypothesis of differential regulation of FSH and LH, and that FSH secretion is at least partly autonomous.  相似文献   
3.
The main biologically active components of plants belonging to the genus Allium, responsible for their biological activities, including anti-inflammatory, antioxidant and immunomodulatory, are organosulfur compounds. The aim of this study was to synthetize the mixture of dipropyl polysulfides (DPPS) and to test their biological activity in acute hepatitis. C57BL/6 mice were administered orally with DPPS 6 h before intravenous injection of Concanavalin A (ConA). Liver inflammation, necrosis and hepatocytes apoptosis were determined by histological analyses. Cytokines in liver tissue were determined by ELISA, expression of adhesive molecules and enzymes by RT PCR, while liver mononuclear cells were analyzed by flow cytometry. DPPS pretreatment significantly attenuated liver inflammation and injury, as evidenced by biochemical and histopathological observations. In DPPS-pretreated mice, messenger RNA levels of adhesion molecules and NADPH oxidase complex were significantly reduced, while the expression of SOD enzymes was enhanced. DPPS pretreatment decreased protein level of inflammatory cytokines and increased percentage of T regulatory cells in the livers of ConA mice. DPPS showed hepatoprotective effects in ConA-induced hepatitis, characterized by attenuation of inflammation and affection of Th17/Treg balance in favor of T regulatory cells and implicating potential therapeutic usage of DPPS mixture in inflammatory liver diseases.  相似文献   
4.
Congenital sacrococcygeal teratoma SCT is the most common germ cell tumor of infancy and childhood with a female preponderance. Most SCTs are diagnosed at birth, are benign, and consist of fully differentiated, mature tissues. Tumorigenesis of SCTs remains poorly understood. Almost nothing is known about possible oncogene activation or tumor suppressor inactivation in these rare tumors. We describe the presence of various oncoproteins and tumor suppressor proteins in eight cases of congenital SCT. The following oncogenes were examined: ras family c-H-, c-N-, and c-K-ras , early genes fos, jun , and tumor suppressor genes p53 and nm23-H-1 . There was no relationship between the intensity of expression of these oncoproteins and tumor suppressor genes and the following parameters: tumor size, age, and survival of the patients. We did not observe any difference, however, between the expression of the examined oncogenes and tumor suppressor genes nm23 and p53 in immature and mature teratomas. Our findings suggest that the ras family of oncogenes, fos and jun oncogenes, and nm23 and p53 tumor suppressor genes are present in congenital SCT, indicating a possible role in genesis and development of these tumors.  相似文献   
5.
The electrochemical behavior of polycrystalline TiO2 anatase coatings prepared by a one-step hydrothermal synthesis on commercially pure (CP) Ti grade 2 and a Ti13Nb13Zr alloy for bone implants was investigated in Hank’s solution at 37.5 °C. The aim was to verify to what extent the in-situ-grown anatase improved the behavior of the substrate in comparison to the bare substrates. Tafel-plot extrapolations from the potentiodynamic curves revealed a substantial improvement in the corrosion potentials for the anatase coatings. Moreover, the coatings grown on titanium also exhibited lower corrosion-current densities, indicating a longer survival of the implant. The results were explained by considering the effects of crystal morphology, coating thickness and porosity. Evidence for the existing porosity was obtained from corrosion and nano-indentation tests. The overall results indicated that the hydrothermally prepared anatase coatings, with the appropriate morphology and surface properties, have attractive prospects for use in medical devices, since better corrosion protection of the implant can be expected.  相似文献   
6.
Solid lipid microparticles were investigated as a taste-masking approach for a lipophilic weak base in a suspension. The idea was that the drug concentration in the aqueous phase of a suspension might be reduced by its partitioning into the solid lipid particles. Loratadine, as a model drug, was used to prepare Precirol® ATO 5 microparticles by a Micromixer. The effects of three process variables: drug loading, PVA concentration and water/lipid ratio on the microparticle size, encapsulation efficiency, surface appearance, in-vitro release and drug partitioning in a suspension were studied. Loratadine release was slow in simulated saliva and very fast at the pH of stomach. In suspension of loratadine lipid microparticles, drug was released into the aqueous phase to the same concentration as in a drug suspension. Therefore, the usefulness of these microparticles for taste-masking in liquids is limited. However, they might be useful for taste-masking in solid dosage forms.  相似文献   
7.
Microcystic adnexal carcinoma (MAC) is a rare, infiltrating, locally aggressive cutaneous neoplasm of combined follicular and eccrine/apocrine histogenesis, usually presenting on the upper lip or face. Differentiation from other adnexal tumours is very important because the clinical management of these tumours is radically different, and misdiagnosis may lead to incorrect treatment. A case of recurrent MAC in the upper lip, treated with multiple excisions and postoperative radiation therapy (PORT), is presented herein. There have been no signs or symptoms of recurrence since the subsequent reconstructive surgery and PORT. Based on reports in the literature it appears that although immunohistochemistry can be helpful in distinguishing between MAC and other adnexal tumours, careful histopathological examination is essential for an accurate diagnosis. Perineural and intramuscular invasion strongly suggest the diagnosis of MAC. Its predilection for the facial area often limits the width of surgical excision. In such cases, PORT may be considered.  相似文献   
8.
BACKGROUND/AIMS: Helicobacter pylori elicits a strong local and systemic humoral immune response, but it is not able to eliminate bacteria. Immune response may be important for the course of infection that may lead to different gastroduodenal disease. In order to investigate differences in systemic humoral immune response between patients with different gastroduodenal diseases, we conducted clinical and serological studies. METHODOLOGY: From 1999 to 2001 we enrolled 80 patients with dyspeptic symptoms: 26 with gastritis, 12 with duodenal ulcer, 29 with gastric cancer and 13 with gastric lymphoma. In all patients during diagnostic work-up we performed ELISA test with Helicobacter pylori-specific IgG and IgA. We investigated difference in stimulation of different immunoglobulin classes in patients with different gastroduodenal diseases, particularly benign and malignant. We estimated significance of differences with Mann-Whitney and Fisher exact probability test. RESULTS: All patients enrolled in the study were seropositive. Patients with gastritis had statistically significant higher level of IgG than patients with gastric cancer (p=0.0001), and gastric lymphoma (p=0.006). Patients with duodenal ulcer had statistically significant higher level of IgG than patients with gastric cancer (p=0.02), and gastric lymphoma (p=0.046). IgA level was significantly higher in patients with gastritis than in patients with gastric cancer (p=0.03). IgA>IgG ratio was significantly more frequent in patients with gastric cancer and gastric lymphoma than in patients with gastritis and duodenal ulcer (p=0.0002). CONCLUSIONS: Result of our study suggested that Helicobacter pylori elicits different systemic humoral immune response in patients with gastritis and duodenal ulcer than in patients with gastric cancer and gastric lymphoma at least in intensity of stimulation of different immunoglobulin classes.  相似文献   
9.
The aim of the paper was to examine the correlation between the total risk of cardiovascular events, determined by the SCORE (Systematic Coronary Risk Evaluation) system, and bone density in postmenopausal women. Examinees and method: The research involved 300 postmenopausal women. On the basis of bone density measurements, the participants were divided into three groups: group I — 84 examinees had osteoporosis, group II — 115 examinees had osteopenia, and group III — 101 examinees had normal bone mineral density (BMD). Results: Participants with high SCORE risk were statistically significantly older compared to low-risk women (60±3 vs. 55±5; p<0.001). They had significantly lower BMD and T scores (?1.09±0.94 vs. ?2.86±0.63; p<0.001). Elevation of the SCORE risk by 1% caused a BMD decrease of 0.033 g/cm2(0.029 to 0.036 gr/cm2). Multivariate logistic regression analysis showed that the following factors caused a significant increase in the risk of decreasing BMD: every year of life by 20%, menopause duration by 26%, increase in systolic blood pressure (BP) by 1 mm Hg by 7%, increase in SCORE risk by 1% by 5.31 times, physical inactivity by 5.96 times, and osteoporosis in the family history by 3.91 times. Conclusion: Postmenopausal women who are at high risk for cardiovascular diseases have a lower BMD than those who are not at high risk for cardiovascular diseases.  相似文献   
10.
Odontomas as a group are the most common odontogenic neoplasms. They are mixed lesions containing fully formatted dental tissues, both epithelial and mesenchymal, and are usually found during a routine radiographic examination or as a factor in noneruption. Odontomas can be divided into two types: the complex and the compound odontoma. Both types are composed of enamel, dentin, cementum and pulp tissues, but in complex odontomas the tissues are arranged in a haphazard fashion with no discernible dental structures, whereas in compound odontomas the dental tissues exist in a more regular pattern so that the lesion consists of tooth-like structures. We report a case of a 23-year-old man with a large complex odontoma involving the left maxilla and maxillary sinus with clinical, radiographic and histological findings. Because of the size of the mass and its clinical course, benign neoplasms were considered in the differential diagnosis. Surgery was the treatment of choice, and recurrence of the lesion is not expected.  相似文献   
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