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991.
Effects of human amniotic fluid on cartilage regeneration from free perichondrial grafts in rabbits.
Güzin Ye?im Ozgenel Gülaydan Filiz Mesut Ozcan 《British journal of plastic surgery》2004,57(5):423-428
After the chondrogenic potential of free grafts of perichondrium was shown in several experimental studies, perichondrium has been used to reconstruct cartilage tissue in various clinical situations. This study investigates the effects of human amniotic fluid on neochondrogenesis from free perichondrial grafts in a rabbit model. Since this fluid contains high concentrations of hyaluronic acid, hyaluronic acid-stimulating activator, growth factors, and extracellular matrix precursors during the second trimester, it may have a stimulating effect on neochondrogenesis. Perichondrial grafts, measuring 20 x 20 mm2 were obtained from the ears of 144 New Zealand young rabbits and were sutured over the paravertebral muscles. The rabbits were randomly divided into three groups with 48 rabbits per group. In group 1, 0.3 ml human amniotic fluid, and in group 2, 0.3 ml saline were injected underneath the perichondrial grafts. Group 3 formed the control group in which no treatment was given. Histologically, neochondrogenesis was evaluated in terms of cellular form and graft thickness at 2, 4, 6, and 8 weeks after surgery. In group 1, the mature cartilage was generated quickly and the cartilage plate in this group was significantly thick and extensive when compared with groups 2 and 3 at 8 weeks ( p<0.05 ANOVA). In conclusion, our study shows that human amniotic fluid enhances neochondrogenesis from free perichondrial grafts. The rich content of hyaluronic acid and growth factors possibly participate in this result. 相似文献
992.
Raquel Carreira Ana Duarte Pedro Monteiro Maria Sancha Santos Ana Cristina Rego Catarina R Oliveira Lino M Gon?alves Luís A Providência 《Revista portuguesa de cardiologia》2004,23(11):1447-1455
Ischemia negatively affects mitochondrial function by inducing the mitochondrial permeability transition (MPT). The MPT is triggered by oxidative stress, which occurs in mitochondria during ischemia as a result of diminished antioxidant defenses and increased reactive oxygen species production. It causes mitochondrial dysfunction and can ultimately lead to cell death. Therefore, drugs able to minimize mitochondrial damage induced by ischemia may prove to be clinically effective. We analyzed the effect of carvedilol, a beta-blocker with antioxidant properties, on mitochondrial dysfunction. Carvedilol decreased levels of TBARS (thiobarbituric acid reactive substances), an indicator of oxidative stress, which is consistent with its antioxidant properties. Regarding cell death by apoptosis, although ischemia did increase caspase-8-like activity, there were no changes in caspase-3-like activity, which is activated downstream of caspase-8; this may indicate that the apoptotic cascade is not activated by 60 minutes of ischemia. We conclude that carvedilol protects ischemic mitochondria by preventing oxidative mitochondrial damage, and, by so doing, it may also inhibit the formation of the MPT pore. 相似文献
993.
Heinz V?ller Clemens Dovifat Johannes Glatz Heinrich K?rtke Uwe Taborski Karl Wegscheider 《European journal of cardiovascular prevention and rehabilitation》2004,11(5):442-447
BACKGROUND: Self management of oral anticoagulation (OAC) decreases complication rates and improves quality of life. Manual and cognitive abilities of patients and patient training in a structured format are a precondition for this concept. Up to now, there is no evidence about knowledge increase from teaching programs. METHODS: Seventy-six patients (mean age, 57.4 years, 71% male) who started long-term OAC were included in the prospective multi-center study at three teaching centers representing different populations of anticoagulation patients: a department of cardiovascular surgery, an inpatient rehabilitation center and an anticoagulation clinic. The patients were trained in a structured education program for two days. For the evaluation, the patients performed standardized tests including 16 questions prior to start (T0), after each training unit (T1/T2) and 6 weeks later (T3). The primary endpoint was the percentage of > or =75% of patients who could answer > or =50% of questions correctly at T3. Secondary endpoints were the overall and item-specific percentages of correct answers at the end of each training unit (T1, T2) and at T3. In addition, the teaching program was rated by the patients on a six-point rating scale. RESULTS: Seventy-four out of 76 patients gave at least 50% correct answers at T3 (97.4%; 95% confidence interval, 90.8-99.7%). The average rates of correct answers developed from 40% (T0), 86% (T1), 94% (T2) to 96% (T3). The greatest increase of knowledge was observed with blood components, interpretation of International Normalized Ratio (INR) value, and the interaction of anticoagulation with other variables (e.g. drugs or infection). Patients rated the teaching program between 1 (best rating) and 2 at all time points. At T3, the patients reported less fear of complications and less limitations in their daily life than in earlier evaluations. CONCLUSION: The structured training program INRatio appears to be an appropriate instrument for instruction of INR self management. In comparison with baseline knowledge, the percentage of correctly answered questions was twice as high directly after the end of training and remained at a high level of >90% for at least 6 weeks. 相似文献
994.
995.
Piotr K?osiński Maciej Gilis-Januszewski Witold Serafin 《Chirurgia narzadów ruchu i ortopedia polska》2004,69(3):167-172
Early results (12 weeks after surgery) of the lumbar spinal stenosis operative treatment were assessed in the group of 36 patients (aged 40-65 years). In 72% of patients posterior fusion was applied. In the results evaluation lumbar pain, low extremities pain, neurogenic claudicat ion, sensory disturbances and functional status were taken in account. A significant decrease in low extremities and lumbar pain was observed. Some sensory disturbances after operative treatment did not affect general high patients assessment of the performed surgical procedures (positive 80.5% cases). 相似文献
996.
W Hunger-Dathe N Mosebach A S?mann G Wolf U A Müller 《Experimental and clinical endocrinology & diabetes》2006,114(1):11-17
AIM: Prevalence of glucose metabolism disorders in women six years after gestational diabetes in the index pregnancy (GDM). METHOD: 227 Caucasian women who developed GDM between 1995 and 1996 were investigated; 173 women (BMI 27.5+/-6.0 kg/m2) received 75 g oGGT on average 5.8+/-2.0 years after delivery. RESULTS: Impaired glucose metabolism was found in 31.2%, IGT or IFG 19.1%, diabetes mellitus type 2 (DM2) 9.2%, diabetes mellitus type 1 (DM1) 2.3%, second GDM 0.6%. 27.2% (BMI 25-29.9 kg/m2) were overweight, 23.1% suffered from obesity (BMI 30-39.9 kg/m2) and 5.2% morbid obesity (BMI>or=40 kg/m2). In comparison to a healthy control group, women with DM2 at re-examination were: older in age (32.1+/-5.9 vs. 29.1+/-4.8 years, p<0.05), had higher BMI (29.4+/-6.9 vs. 24.6+/-4.8 kg/m2, p<0.05), higher fasting blood glucose (6.5+/-1.9 vs. 5.2+/-0.9 mmol/l, p<0.05), earlier diagnosis of GDM (25+/-8 vs. 29+/-5 SSW, p<0.05), more frequent insulin therapy during pregnancy (75 vs. 24%) and had significantly higher insulin- and C-peptide for all measures of the oGTT, whereas HbA1c was not different (4.9+/-0.5 vs. 4.8+/-0.3%, n. s.). CONCLUSION: In an average of 5.8 years after the diagnosis of GDM, the majority of women still have chronic insulin resistance. One third has either IGT, IFG or diabetes mellitus. Therefore, a long term follow-up is strongly recommended for women diagnosed with GDM. 相似文献
997.
K Müssig S Kaltenbach C Maser-Gluth M F Hartmann S A Wudy M Horger B Gallwitz F Raue H-U H?ring E Schulze 《Experimental and clinical endocrinology & diabetes》2006,114(4):208-214
Congenital adrenal hyperplasia results from 21-hydroxylase deficiency in more than ninety percent of cases. The classical form of 21-hydroxylase deficiency presents in the neonatal period with virilization or adrenal insufficiency, with or without concurrent salt wasting. We report on a rare case of classic 21-hydroxylase deficiency diagnosed in late adulthood. A 39-year-old male patient presented for workup of infertility. Urologic investigation revealed small testes, bilateral testicular masses, and asthenozoospermia. The patient's steroid metabolism showed markedly increased levels of adrenal androgens, in particular of 17-hydroxyprogesterone amd 21-deoxycortisol. The gas chromatographic-mass spectrometric (GC-MS) urinary steroid profile was dominated by metabolites of 17-hydroxyprogesterone, while the endogenous glucocorticoid production was subnormally low. ACTH levels in plasma were elevated. These hormonal findings were consistent with 21-hydroxylase deficiency. Therapy with dexamethasone was initiated. The CTP21A2 gene analysis revealed the mutation I172N (ATC --> AAC) in exon 4 of allele 1 and a large gene deletion in allele 2. Cases of 21-hydroxylase deficiency diagnosed in late adulthood are rare; however, clinicians should be alert of this possibility. 相似文献
998.
Martin Krause Wolfgang Fogel Volker Tronnier Sabine Pohle Konstanze H?rtnagel Ute Thyen Jens Volkmann 《Movement disorders》2006,21(12):2255-2257
Pantothenate kinase-associated neurodegeneration (PKAN) is a rare autosomal recessive disorder with onset in childhood and rapid progression. There is no causative and insufficient symptomatic drug therapy. Deep brain stimulation (DBS) of the internal pallidum (GPi) has been reported to improve motor function. Most case reports, however, are limited to short observational periods. The impact of DBS on the progression and life expectancy in PKAN is unknown. We present a 5-year outcome and video documentation of bilateral GPi-DBS of an adolescent patient suffering from genetically defined PKAN. 相似文献
999.
1000.
M Medina-Ramón J P Zock M Kogevinas J Sunyer X Basaga?a J Schwartz P S Burge V Moore J M Antó 《The European respiratory journal》2006,27(6):1196-1203
Symptoms of obstructive lung disease in domestic cleaners have been related to the use of bleach and other irritant cleaning products. The short-term effects of cleaning exposures on respiratory symptoms and peak expiratory flow (PEF) were investigated in domestic cleaners with respiratory disorders. In a panel study, 43 female domestic cleaners with a recent history of asthma and/or chronic bronchitis completed a 2-week diary, collecting information on respiratory symptoms, PEF and cleaning exposures. Mixed regression models were used to assess daily changes in symptoms and PEF associated with specific cleaning exposures. The probability of having work-related asthma was individually assessed by a computerised diagnostic system and an occupational asthma expert. Lower respiratory tract symptoms were more common on working days and were predominantly associated with exposure to diluted bleach, degreasing sprays/atomisers and air fresheners. Associations with upper respiratory tract symptoms and PEF were less apparent. Eleven (30%) subjects scored positively for work-related asthma. It is concluded that exposure to certain irritant cleaning products aggravates lower respiratory tract symptoms in female domestic cleaners with asthma or chronic bronchitis. 相似文献