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61.
62.
Establishing guidelines and experimental models preclinical and clinical evaluations of new agents for treatment, and/or prevention of human diseases has become a task of crucial importance. Psoriasis is such one disease holding great interest for dermatology owing to its high rate of incidence and complexity of treatment. However the absence of psoriatic lesions in animals and the inability to induce them, calls for experimental techniques both in vitro and in vivo. The purpose of this study was to evaluate experimentally the effects of tacalcitol on cell proliferation and differentiation process. Thereafter a human pilot study on psoriatic patients has been developed.  相似文献   
63.
One of many problems to be faced when assessing in vivo human muscle mitochondria respiration by phosphorus magnetic resonance spectroscopy (31P-MRS) is the definition of the correct reference population and the values of reference range. To take into account most factors that influence muscle activity as age, sex, physical activity; nutritional state etc., an exceedingly high number of different reference groups are needed. To overcome this problem we developed specific tests to assess separately in vivo the activity and the functionality of muscle mitochondria by 31P-MRS in clinical settings. By activity we refer to muscle whole metabolic activity, i.e. the total oxidative capacity of muscle mitochondria which is influenced by many factors (age, sex, physical activity, nutritional state etc.). By functionality we refer to the qualitative aspects of mitochondrial respiration which depends on the integrity of mitochondrial multienzyme systems and on substrate availability. Our tests have been experienced on some 1200 patients and are currently used to detect deficits of mitochondrial respiration and ion transport in patients with suspected primary or secondary muscle mitochondrial malfunctioning.  相似文献   
64.
Reference two-dimensional (2-D) gels are presented for human breast ductal carcinoma and histologically normal tissue. Whole biopsy fragments were analyzed, including epithelial and nonepithelial components. Thirty-five spots have been assigned by gel matching to the human liver SWISS-2DPAGE reference map and/or to the human primary keratinocyte IPG map from the Danish Center for Human Genome. N-terminal microsequencing was applied to confirm randomly chosen matching assignments and to identify six new spots. Protein expression profiles in ductal carcinoma and in normal breast tissue appeared to be similar, except for a pattern consisting of 32 spots, which were highly expressed in all carcinoma specimens, and less intense and occasionally undetectable in normal tissue. This difference was statistically significant. Assignment has been obtained for several spots, namely GRP94, GRP78, GRP75, mitochondrial HSP60, calreticulin, protein disulfide isomerase, peptidyl-prolyl cis-trans isomerase, collagen-binding protein 2, fructose bisphosphate aldolase, glyceraldehyde-3-phosphate dehydrogenase, thioredoxin, cytochrome c oxidase VA subunit, tubulin beta isoform and macrophage migration inhibitory factor (MIF). The cancer- and tissue-specificity of the described pattern was assessed by matching to the Swiss-2DPAGE human liver, hepatoma, lymphoma, erythroleukemia reference maps. The pattern of 32 spots was found to be indicative of epithelial neoplasia.  相似文献   
65.
Contact stomatitis is rather uncommon because of the relative resistance of the oral mucosa to irritant agents and allergens. The clinical manifestations of contact stomatitis are extremely variable and include erythema, erosions, ulcerations, leukoplakia-like lesions, and lichenoid reactions. Clinical signs are frequently less pronounced than subjective symptoms, and patients commonly experience severe functional problems despite only mild mucosal alterations. Allergic stomatitis is rare and almost always attributable to metallic mercury and gold salts. A careful history and an accurate examination of the oral cavity, teeth, and dental restorations are essential for a correct diagnosis. Patch testing is indicated in all lesions that are not clearly related to trauma or physical injuries. Patch testing is not useful in the burning mouth syndrome. Evaluation of clinical relevance of patch test results is always very difficult and requires an interdisciplinary approach to the patient. Successful treatment requires the identification and elimination of the causative factor, when possible. It is important to bear in mind that replacement of dental restorations and prostheses may be very expensive and stressful for the patient and thus should not be recommended when their causative role is doubtful.  相似文献   
66.
AIM: We highlight the occurrence of an unusual neuroendocrine tumour, a large cell neuroendocrine carcinoma, arising from the thymus. CASE DETAILS: A 68-year-old man with a history of cigarette smoking had a large mediastinal tumour arising from the thymus removed. Two years later the tumour recurred; it was debulked surgically but the patient died 2 months later: Histological examination of both tumour specimens revealed a tumour with an endocrine pattern, composed of large pleomorphic cells with large nuclei and prominent nucleoli. The mitotic count ranged from 19 to 26 per 10 high-power fields and large tracks of coagulative tumour necrosis were present. The tumour cells were strongly positive for neuron-specific enolase (NSE), chromogranin, CAM5.2 and AE1/3, with cytoplasmic dot-like accentuation for the latter three markers. The tumour fulfilled the criteria for a diagnosis of large cell neuroendocrine carcinoma. CONCLUSIONS: Large cell neuroendocrine carcinoma should be distinguished from atypical carcinoid and small cell carcinoma. It is a distinctive neuroendocrine malignancy with a prognosis between that of atypical carcinoid and small cell carcinoma, and needs to be treated aggressively.  相似文献   
67.
Two more cases of late onset peripheral seronegative spondyloarthropathy (SpA) are reported. Like the patients reported by Dubost and Sauvezie, they had extensive pitting edema of the lower limbs, constitutional symptoms, elevated erythrocyte sedimentation rate and minimal involvement of the axial skeleton with marked signs of diffuse idiopathic skeletal hyperstosis.  相似文献   
68.
Left ventricular (LV) thrombosis can be found in patients with acute myocardial infarction (AMI). No wide multicenter trial on AMI has provided information about LV thrombosis until now. The protocol of the GISSI-3 study included the search for the presence of LV thrombosis in patients from 200 coronary care units that did not specifically focus on LV thrombosis. We examined the GISSI-3 database results related to 8,326 patients at low to medium risk for LV thrombi in which a predischarge echocardiogram (9 +/- 5 days) was available. LV thrombosis was found in 427 patients (5.1%): 292 of 2,544 patients (11.5%) with anterior AMI and in 135 of 5,782 patients (2.3%) with AMI in other sites (p <0.0001). The incidence of LV thrombosis was higher in patients with ejection fraction < or = 40% (151 of 1,432 [10.5%] vs 276 of 6,894 [4%]; p <0.0001) both in the total population and in the subgroup with anterior AMI (106 of 597 [17.8%] vs 186 of 1,947 [9.6%]; p <0.0001). Multivariate analysis showed that only the Killip class > I and early intravenous beta-blocker administration were independently associated with higher LV thrombosis risk in the subgroup of patients with anterior AMI (odds ratio 1.75, 95% confidence interval 1.28 to 2.39; odds ratio 1.32, 95% confidence interval 1.02 to 1.72, respectively). In patients with anterior AMI, oral beta-blocker therapy given or not given after early intravenous beta-blocker administration does not influence the occurrence of LV thrombosis. The rate of LV thrombosis was similar in patients treated or not treated with nitrates and lisinopril both in the total population and in patients with anterior and nonanterior AMI. In conclusion, in the GISSI-3 population at low to medium risk for LV thrombi, the highest rate of occurrence of LV thrombosis was found among patients with anterior AMI and an ejection fraction < 40%. Killip class > I and the early intravenous beta-blocker administration were the only variables independently associated with a higher predischarge incidence of LV thrombosis after anterior AMI.  相似文献   
69.
This study investigated the effect on vertical bone regeneration of the addition of demineralized freeze-dried bone allograft or autogenous bone chips to a membrane technique. Twenty partially edentulous patients with vertical jawbone deficiencies were selected for this study. The patients were divided into two groups of 10 individuals. The 10 patients of Group A received 26 Br?nemark implants in 10 surgical sites. The 10 patients of Group B received 32 implants in 12 surgical sites. Fifty-two out of 58 implants (22 in Group A and 30 in Group B) extended 1.5 to 7.5 mm superior to the bone crest. Titanium-reinforced expanded polytetrafluoroethylene membranes were used to cover the implants and, before complete membrane fixation, demineralized freeze-dried bone allograft particles were condensed under the membrane in Group A, and autogenous bone chips were used in Group B. At the reentry after 7 to 11 months the membranes were removed and a small biopsy was collected from 11 sites comprehending the miniscrews. The clinical measurements from Group A demonstrated a mean vertical bone gain of 3.1 mm (SD = 0.9 mm, range 1 to 5 mm) with a mean percentage of bone gain of 124% (SD = 46.6%). The measurements from Group B showed a mean vertical bone gain of 5.02 mm (SD = 2.3 mm, range 1 to 8.5 mm) with a mean percentage of bone gain of 95% (SD = 26.8%). Histomorphometric analysis of the present study clearly demonstrated a direct correlation between the density of the pre-existing bone and the density of the regenerated bone. The mean percentage of new bone-titanium contact was from 39.1% to 63.2%, depending on the quality of the pre-existing bone. Both the clinical and histologic results indicate a beneficial effect of the addition of demineralized freeze-dried bone allograft or autogenous bone particles to vertical ridge augmentation procedures in humans.  相似文献   
70.
Two specific methods for the simultaneous determination of nimesulide, a non steroidal anti-inflammatory drug, and its hydroxylated metabolite in human plasma are described. Adopting a high performance liquid chromatographic (HPLC) system with UV detection (230 nm), the compounds, extracted from plasma in acidic medium, were separated on ODS columns under gradient conditions, using a phosphate buffer solution and methanol as mobile phase. For each method column length, gradient rate and composition were appropriately selected. The limit of quantitation was 25 ng/mL for both compounds. The two methods were validated by intra day assays at three concentration levels and applied in kinetic studies in healthy volunteers, during which inter-day assays were carried out confirming their feasibility.  相似文献   
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