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1.
Low molecular weight heparins are widely used in the prophylaxis and treatment of thrombotic disorders. The effect of low molecular weight heparins on coagulation was examined ultrastructurally in an animal model. A test and a control group was formed, each consisting of five rabbits. Nadroparine (225 Institute of Chaoy Unit/kg twice daily) was applied to the test group for 10 days. The control group received 1 ml saline solution subcutaneously. Blood and vascular tissue samples collected at the end of the 10th day were evaluated under a JEM 100 B electron microscope. Platelet degranulation and agglutination was observed in the control group. Fibrin materials were detected in the cytoplasms and surroundings of degranulated platelets. Erythrocyte accumulation was remarkable on the vascular endothelium with intact coagulation periods. In the test group, outer membranes of platelets, hyalomere, and granular structures in the granulomeres were detected to be nearly intact. There were rare erythrocytes in the large vascular lumens. The aggregation phase had occurred but no agglutination was detected. Nadroparine seems to preserve consistency of lipoprotein membranes of platelets and granular structures containing enzymes, which contribute to the coagulation mechanisms.  相似文献   
2.
Ligneous periodontitis (LP) is a rare periodontal disease in which plasminogen deficiency and fibrin deposition both play a part, resulting in characteristic gingival enlargement and periodontal breakdown. Recent data suggest that oxidant/antioxidant changes are significant in the pathology of oral diseases. This study examines the gingival histopathology in 2 cases with LP. To examine the antioxidant (AO) status, the activity of the major AOs glutathione (GSH), catalase (CAT), and glutathione S-transferase (GST) and the malondialdehyde (MDA) levels, a product of lipid peroxidation, were measured and compared with healthy control subjects. The histopathologic examination of the gingiva revealed subepithelial fibrin accumulation and irregular extensive downward proliferation of the epithelium. Biochemical analysis showed that the CAT, GST, and MDA levels were higher in LP patients than in the control subjects, and the GSH level was lower. Our preliminary findings show that in LP, the AO capacity of the gingiva changes or decreases and lipid peroxidation increases, which suggests that oxidative stress is involved in the pathology of the periodontal breakdown observed in this disease.  相似文献   
3.
Summary The effects of pineal gland, an endocrine organ known to affect the physiology of various organs and systems including the hypothalamo-hypophyseal axis, on the morphological characteristics of target organs were investigated in rats after pinealectomy and foetal pineal gland transplantation to a subpial cortical area close to the pinealectomized region.It was demonstrated that weight gain was significantly slower in pinealectomized male rats (p<0.01); pituitary gland weight was lower in the pinealectomized group (p<0.01) and transplantation had no effect on the weight of this organ; weight of adrenal gland and testis were lower after pinealectomy (p<0.01) but restored back to control levels after transplantation; the mitotic activity in seminiferous tubules increased with pinealectomy and returned back to control indexes after transplantation.Research on hypothalamic catecholaminergic content revealed a diminished histofluorescence in pinealectomized rats which showed a potentiated restoration after transplantation.The innervation of the pineal gland was studied by anterograde and retrograde injections of Wheat Germ Agglutinin Horse Radish Peroxidase from superior cervical ganglion and pineal gland, respectively. It was demonstrated that cell bodies were traced both at the transplanted tissue and hypothalamus.In view of these data, the multifunctional and a probable high level homeostatic harmony regulator essence of pineal gland is discussed.The paper has been awarded the 1993 Upjohn prize for Neurosurgical Research of the European Association of Neurosurgical Societies.  相似文献   
4.
Chlamydial infections and male infertility   总被引:3,自引:0,他引:3  
Chlamydial infections may be difficult to diagnose due to the silent symptoms and difficulty in culturing. An infectious process may impair fertility by adversely affecting sperm functions, resulting in testicular damage or causing obstruction of the genital tract. In our study, we tried to find Chlamydial antigen by using EIA (Enzyme Immune Assay) and to compare the Ag(+) and Ag(−) groups according to semen parameters. Except for semen volume, we found significant differences in density, morphology, motility and viability (intervolume p>0.05, interdensity p<0.01, intermorphology p<0.001, intermotility p<0.001 and interviability p<0.001).  相似文献   
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6.
The clinical patterns and predictors of cytomegalovirus (CMV) disease in kidney and/or pancreas transplant patients on ganciclovir (1.0 g po t.i.d.) or valganciclovir (450 mg po q.d.) prophylaxis were studied. This is a retrospective analysis of 129 transplant recipients. Median follow up was 12 months (range, 6-18 months). The overall incidence of CMV disease at 1-year post-transplant was 14% (4% tissue-invasive, 10% noninvasive). Seventeen of 18 patients were diagnosed with CMV after completion of 3 months' prophylaxis (median 8 weeks, range, 2-28 weeks). Induction treatment with thymoglobulin, and Donor +/Recipient - CMV status were the strongest predictors for the development of CMV disease. Cytomegalovirus incidence was not different between patients treated with ganciclovir or valganciclovir (15 vs. 17%, respectively). Valganciclovir (450 mg q.d.) is as effective as oral ganciclovir in CMV prophylaxis. High-risk individuals might require higher doses or longer duration of valganciclovir treatment.  相似文献   
7.
BACKGROUND: Atherosclerotic vascular diseases are the major cause of mortality in patients with end-stage renal disease (ESRD) treated with chronic peritoneal dialysis (CPD), even in children. Adiponectin (ADPN) is a recently discovered adipocyte-derived plasma protein having anti-atherogenic properties. ADPN levels are elevated in ESRD but it has been reported that ESRD patients with low plasma ADPN levels have a high risk of cardiovascular death. OBJECTIVE: To clarify the atherosclerotic risk and especially the significance of ADPN levels in pediatric patients on CPD. DESIGN: Cross-sectional studyin the pediatric peritoneal dialysis unit of a university hospital. PATIENTS: 18 children, aged 12.6 +/- 5.6 years, being treated with CPD and 20 healthy age- and sex-matched control subjects were enrolled in this study. METHODS: Serum ADPN levels and other risk factors, including blood pressure, blood glucose, serum lipid/lipoprotein fractions, apolipoprotein B, C-reactive protein (CRP), lipoprotein(a), and homocysteine levels, were studied in CPD patients and compared to the controls. RESULTS: Serum ADPN levels were three times higher in the CPD group compared to the control subjects, as was previously reported. Apolipoprotein B and CRP levels were also high in the CPD group. No significant difference was found in other atherosclerotic parameters, including lipoprotein(a) and homocysteine levels. Interestingly, we found a negative correlation between log ADPN and creatinine levels among the CPD patients (r = -0.54, p < 0.05). There was no correlation between log ADPN and duration of CPD. Creatinine and low-density lipoprotein levels could account for 54% of the total variation in ADPN levels. CONCLUSION: Among pediatric CPD patients, serum levels of the anti-atherogenic protein, ADPN, were inversely associated with creatinine. ADPN level might be a novel marker to predict prognosis in pediatric CPD patients.  相似文献   
8.
Mural thrombosis of the left atrium is a complication of mitral valve replacement. In this report we present a case of mural thrombosis of the left atrium after mitral valve replacement treated successfully without surgical intervention.  相似文献   
9.
To determine the efficacy of ketoconazole in the treatment of hirsutism, clinical and hormonal effects of this agent were evaluated with a randomized, placebo-controlled, double-blind cross-over study design. Nine hirsute women were given ketoconazole (600 mg/day) or placebo for 6 months and then crossed over. The severity of hirsutism was assessed according to the scale of Ferriman & Gallwey. Baseline serum testosterone, dehydroepiandrosterone sulphate, progesterone, estradiol, basal and stimulated cortisol and 17-alpha hydroxyprogesterone were measured. Blood was also drawn for FSH and LH levels at 0, 30, 60, and 90 min of a GnRH stimulation test. The same parameters were determined following administration of placebo or ketoconazole for 6 months. The pretreatment (28.3 +/- 0.9) and post-placebo (27.7 +/- 1.4) Ferriman-Gallwey scores were significantly higher than the post-ketoconazole score (16.6 +/- 1.3, p less than or equal to 0.01). Basal and stimulated cortisol levels were not blunted after ketoconazole, but basal and stimulated 17-hydroxyprogesterone levels were significantly higher, indicating sufficient enzymatic inhibition. Serum dehydroepiandrosterone sulphate and testosterone levels were significantly lowered following ketoconazole (p less than or equal to 0.05). Although E2 levels did not change significantly at any time, E2:testosterone ratios were significantly higher after ketoconazole (p less than or equal to 0.01), and the LH:FSH area ratio was also significantly greater than 3 after ketoconazole. It is concluded that ketoconazole significantly alleviates hirsutism by inhibiting steroid synthesis.  相似文献   
10.
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