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Liver disease alters the pharmacokinetic and pharmacodynamic properties of hepatically eliminated drugs. The main factors influenced are plasma albumin levels, enzyme balance (induction & inhibition) and drug binding to tissue proteins. The influence of lidocaine on serum, heart and liver propranolol levels in Wistar rats after liver injury induced by carbon tetrachloride CCl4 0.4 ml/kg x 2/wkl, was investigated. 40 male Wistar rats were divided into four groups (I, II, III, IV; n=10), Group I animals received only propranolol (labelled + cold substance) 40 mg/kg/12 h p.o., group II propranolol plus lidocaine in a single dose of 4mg/kg s.c., group III was treated with CCl4 for 6 weeks and received propranolol x2 at the same dosage as group I, while group VI was treated with CCl4 and the same drug dosage as group II. The simultaneous administration of H3-propranolol and lidocaine increased propranolol levels in the serum and tissues. The liver in damaged animals showed an increase of propranolol level under lidocaine co-administration, probably due to CCl4 induced liver enzyme activity, resulting in a rapid propranolol metabolism or to competition between both drug protein binding sites. The increased propranolol levels in the heart after lidocaine administration were probably due to attributed to its high affinity for heart tissue. Consequently, as regards the therapeutic approach for patients with liver disease receiving propranolol their propranolol dosage should be reduced when lidocaine is co-administered.  相似文献   
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The overnight one-mg dexamethasone suppression test has been used for many years to screen for Cushing's syndrome. This test has usually been evaluated in controls versus patients with severe hypercortisolism. Under these conditions, the overnight dexamethasone suppression test has been reported to have high sensitivity and specificity. The objective of this study was to determine the sensitivity of the one mg overnight dexamethasone suppression test in patients with mild and/or periodic Cushing's syndrome. Therefore, an overnight dexamethasone suppression test was performed in 17 consecutive patients presenting to an endocrinology clinic with signs and symptoms of hypercortisolemia who were later proven to have Cushing's syndrome. The majority of patients were found to have both mild and periodic hypercortisolism. One mg of dexamethasone was given at midnight and a plasma cortisol was measured by radioimmunoassay at 08:00 the following morning. Using a cut-off for a morning cortisol following overnight dexamethasone of > 5 microg/dL, only three of 17 patients failed to suppress to a value less than this cut-off (sensitivity 18 %). A cut-off of > 2 microg/dL gave similar sensitivity. Even with a stringent cut-off point of > 1.8 microg/dL, only seven of 17 patients failed to suppress to a value less than this cut-off point (sensitivity of 41 %). These results demonstrate that the great majority of patients with mild and/or periodic Cushing's syndrome suppress to overnight dexamethasone. Since patients with mild and/or periodic Cushing's syndrome are the patients in whom the identification of hypercortisolism is difficult, our results from this relatively small study suggest that this test should no longer be used to exclude these patients from further workup for Cushing's syndrome.  相似文献   
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Vitiligo and psoriasis are both common skin disorders. However, psoriasis strictly confined to pre-existing vitiligo areas is rare and suggests a causal relationship. We report here on two patients with a strict anatomical colocalization of vitiligo and psoriasis. The histopathological examinations showed typical changes for both diseases together with a dense infiltrate of CD4+ and CD8+ T cells. By immunohistochemistry, intracytoplasmatic granzyme B and tumour necrosis factor alpha (TNF-alpha) were detected within the T-cell population, suggesting the functional activity of these cells and the creation of a local T helper 1 (Th1)-cytokine milieu. Additionally, in one patient we could identify anti-melanocytic T cells by tetramer staining and enzyme-linked immunospot (ELISPOT) analysis. These skin-infiltrating lymphocytes might trigger, by the local production of Th-1 cytokines such as TNF-alpha and interferon-gamma (IFN-gamma), the eruption of psoriatic plaques in patients with a genetic predisposition for psoriasis.  相似文献   
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AIM: To evaluate whether the introduction of a strict protocol approach based on the systemic evaluation of critically ill pregnant women with complications of abortion affected outcome. SETTING: Indigent South Africans managed in the regional and tertiary hospitals of the Pretoria Academic Complex. METHOD: Since 1997 a standard definition of severe acute maternal morbidity (SAMM) has been used in the Pretoria Academic Complex. All cases of SAMM and maternal deaths were entered on the Maternal Morbidity and Mortality Audit System programme. A comparison of outcome of severely ill women who had complications of abortion was made between 1997-1998 (original protocol) and 2002-2004 (strict protocol). OUTCOME MEASURES: The mortality index and prevalence of organ system failure or dysfunction. RESULTS: In 1997-1998 there were 43 women with SAMM who survived and a further 10 maternal deaths due to complications of abortion, compared with 107 women with SAMM and 7 maternal deaths during 2002-2004. The mortality index declined from 18.9% in 1997-1998 to 6.1% in 2002-2004 (p = 0.02, odds ratio 0.28, 95% confidence limits 0.10 - 0.79). Significantly more women had hypovolaemic shock in 2002-2004 compared with 1997-1998 (54.4% v. 35.8%, p = 0.04), but fewer women had immune system failure including septic shock (18.4% v. 47.2%, p = 0.0002) and metabolic dysfunction (0 v. 5.7%, p = 0.03) and there was a trend to less renal failure (10.5% v. 22.6%, p = 0.06) and cardiac failure (4.4% v. 13.2%, p = 0.08). CONCLUSION: The strict protocol approach based on systemic evaluation in managing critically ill pregnant women with complications of abortion, coupled with an intensive, regular feedback mechanism, has been associated with a reduction in the mortality index.  相似文献   
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We aimed to evaluate the potential of the cerebrospinal fluid (CSF) axonal damage biomarker NfH(SMI35) in the laboratory-supported differential diagnosis of parkinsonian syndromes. Patients with idiopathic Parkinson's disease (PD; n = 22), multiple-system atrophy (MSA; n = 21), progressive supranuclear palsy (PSP; n = 21), corticobasal degeneration (CBD; n = 6), and age-matched controls (n = 45) were included. CSF levels of NfH(SMI35) were measured using ELISA. Levels of CSF NfH(SMI35) were elevated in PSP compared to PD and controls (P < 0.05 each). They were also significantly higher in MSA than in PD and controls (P < 0.05 each). NfH(SMI35) differentiated PD from PSP with a sensitivity of 76.5% and a specificity of 94.4%. Axonal damage as measured by CSF NfH(SMI35) is most prominent in the more rapidly progressive syndromes PSP and MSA as compared to PD or CBD. CSF NfH(SMI35) may therefore be of some value for the laboratory-supported differential diagnosis of atypical parkinsonian syndromes.  相似文献   
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The aim of the study was to evaluate differences in the relationship between peripheral diabetic neuropathy and microvascular reactivity in type 1 and type 2 diabetic patients. Twenty-eight type 1 and 37 type 2 diabetic patients were included in the study. Control groups consisted of 18 and 25, age and body mass index matched healthy persons. The presence of peripheral neuropathy was estimated by vibration perception threshold higher than 20 V evaluated by biothesiometry. Microvascular reactivity was examined by laser doppler fluxmetry using postocclusive reactive hyperemia and thermal hyperemia. The following variables of vascular reactivity were examined: peak flow after occlusion as a difference between maximal and basal perfusion (PORH (max)), mean velocity increase during postocclusive hyperemia (PORH (max)/t (1)), peak flow during thermal hyperemia (TH (max)) and the mean velocity increase in the perfusion during thermal hyperemia (TH (max)/t (2)). These parameters are expressed in perfusion units (PU) or in perfusion units per second (PU . s (-1)). The microvascular reactivity in type 1 diabetic patients without evidence of peripheral neuropathy was comparable with that in healthy persons and it was significantly higher than in type 1 diabetic patients with peripheral neuropathy in all tested parameters (PORH (max): 64 [40; 81] PU vs. 24 [17; 40] PU, p < 0.001, PORH (max)/t (1): 5.41 [2.69; 8.18] PU/s vs. 1.21 [0.69; 2.5] PU/s, p < 0.001, TH (max): 105 [77; 156] PU vs. 56 [46; 85] PU, p < 0.001 and TH (max)/t (2): 2.48 [1.67; 3.33] PU/s vs. 0.87 [0.73; 1.06] PU/s, p < 0.001). On the contrary, no difference in the microvascular reactivity parameters was found between type 2 diabetic patients with and without neuropathy (PORH (max): 48 [30; 60] PU vs. 49 [36; 57] PU, NS, PORH (max)/t (1): 3.46 [2.15; 5.19] PU/s vs. 3.29 [2.45; 4.8] PU/s, NS, TH (max): 95 [78; 156] PU vs. 97 [73; 127] PU, NS and TH (max)/t (2): 1.45 [0.95; 2.84] PU/s vs. 1.37 [1.12; 1.95] PU/s, NS). In both these groups microvascular reactivity was comparable with that estimated in the age and BMI matched healthy persons. An inverse relationship was observed between microvascular reactivity and vibratory perception threshold in type 1 diabetic patients, but it was not true in type 2 diabetic patients. We suppose that the pathogenesis of neuropathy and impaired microvascular reactivity may be differently influenced by metabolic factors in type 1 and type 2 diabetic patients.  相似文献   
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