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12.
A novel chiral redox-active ferrocene compound (FcVI) with amphiphilic properties has been synthesized. Cryogenic Transmission Electron Microscopy (cryo-TEM) has been used to estimate the shape and size of the FcVI aggregates in solution. Uni- and multi-lamellar vesicles (between 40 and 300 nm in diameter) were observed in water. Large particles (of more than 1 μm in diameter) with a hexagonal fine structure were found in 50 mM aqueous Na2SO4 solution. Sonication transformed the latter into ‘rosette’-like structures. Cyclic voltammetry has been employed to investigate the electrochemical properties of FcVI. The amphiphile adsorbed on graphite electrodes and a reversible electrochemical behaviour, characteristic of ferrocene, was observed with redox potentials between 330 and 350 mV.  相似文献   
13.
N-Nitrosodibutylamine (NDBA) and its omega-oxidized metabolites N-nitrosobutyl-4-hydroxybutylamine (4-OH-NDBA) and N-nitrosobutyl-3-carboxypropylamine (BCPN) are potent urinary bladder carcinogens. To study putative organ specific activation of BCPN, its alpha-oxidation by liver and urinary bladder microsomal fractions was investigated in comparison to NDBA and 4-OH-NDBA. Additionally, induction of DNA single strand breaks (SSB) was monitored in hepatocytes and in a human lymphoblastoid cell line (Namalva) in the presence and absence of external metabolic activation, including N-nitroso-t-butyl-n-butylamine as a negative control. BCPN was alpha-hydroxylated and dealkylated at both alkyl chains in small rates (about 1 nmol x mg protein-1 x 60 min-1) by microsomes from rat liver and pig urinary bladder epithelium. NDBA and 4-OH-NDBA were dealkylated at similarly low rates by pig urinary bladder microsomes, in strong contrast to the high debutylation rates observed for rat liver microsomes. Correspondingly, SSB induction by NDBA and 4-OH-NDBA was observed in Namalva cells with NDBA and 4-OH-NDBA in the presence of PB-induced rat liver microsomes but not with urinary bladder microsomes or without external activation. BCPN did not induce DNA-damage in Namalva cells (with or without external activation) or in rat hepatocytes. Significant induction of sister chromatid exchanges (SCEs) and micronuclei, however, was observed in Namalva cells after incubation with NDBA and BCPN. Our data suggest activation of BCPN via alpha-oxidation in the urinary bladder, even though activation rate in-vitro is so low that a positive response is not detectable by several short-term tests.  相似文献   
14.
Bitran  Jacob D. 《JAMA》2005,293(23):2940
  相似文献   
15.
We dissected 20 preserved Caucasian cadaveric upper limbs looking at the relation of the superficial branch of the radial nerve (SBRN) to the brachioradialis tendon. SBRN emerged from deep to superficial position by piercing the brachioradialis tendon near its dorsal border in four limbs. The resulting dorsal tendinous band compressed the nerve and prevented longitudinal gliding movement during ulnar flexion. This is likely to increase the risk of chronic compression neuropathy (Wartenberg's syndrome). In two of these four limbs, there was a communication between the SBRN and lateral cutaneous nerve of the forearm. No such communication was found in the remaining 16 forearms. This communication could contribute to the minimal area of sensory loss observed in Wartenberg's syndrome. We recommend that this anatomical anomaly is looked for and if present dealt with during surgical treatment of Wartenberg's syndrome, as it is likely to predispose to chronic compression neuropathy.  相似文献   
16.
BACKGROUND: Intrahepatic stones, though common in East Asia, are uncommon in India. There is paucity of data from India regarding the treatment and long-term outcome of patients with intrahepatic stones. METHODS: We retrospectively analyzed medical records of 35 patients with intrahepatic stones who had been treated surgically. Endoscopic biliary drainage had been used in patients who presented with acute cholangitis. Intraoperative stone clearance was confirmed by choledochoscopy and intraoperative cholangiography. Outcome of surgery, frequency and subsequent management of recurrent intrahepatic stones, and factors associated with stone recurrence and cholangitis were analyzed. RESULTS: Twenty-one (60%) patients had bilobar disease. Eight patients underwent hepatectomy and 16 hepatico-jejunostomy with access loop; 12 of these were jejuno-duodenal anastomoses. Postoperative morbidity was observed in 10 patients (29%). Recurrence of stones occurred in 12 patients (34%) and cholangitis in 9 patients (26%). Presence of bilobar disease and associated biliary strictures were associated with recurrent cholangitis (p< 0.05). Two patients (6%) required re-operation for recurrent cholangitis. Complete removal of recurrent stones using conventional endoscope was possible through jejuno-duodenostomy in all 5 cases who had this type of access loop construction. CONCLUSION: Surgical treatment for intrahepatic stones depends on the site of involvement. Construction of a jejuno-duodenal access loop in patients with bilobar disease and intrahepatic strictures is helpful in facilitating postoperative stone clearance. A multidisciplinary approach is beneficial especially when the disease is bilobar and recurrent in type.  相似文献   
17.
BACKGROUND: Wall-motion analysis during low-dose dobutamine echocardiography (LDDE) is a semiquantitative measure of left ventricular contractile reserve after myocardial infarction (MI). The Doppler echocardiographic myocardial performance index (MPI) is a quantitative measure of combined left ventricular systolic and diastolic function. We sought to characterize the changes in MPI during LDDE in control subjects and patients with MI, and to describe the relation of these changes to changes in regional systolic function. METHODS: MPI was obtained at rest and during LDDE (10 microg/kg/min) in 25 healthy volunteers (group 1) and 50 patients with a recent MI. Patients were divided into two subsets; those with (n = 23; group 2A) and those without (n = 27; group 2B) a contractile reserve defined as an improvement of wall motion in more than two contiguous infarct-zone segments during LDDE. DeltaMPI was defined as the change from rest to LDDE. RESULTS: MPI decreased significantly during LDDE in groups 1 and 2A, whereas MPI increased in group 2B (DeltaMPI = 0.12 +/- 0.04 and 0.10 +/- 0.08 vs -0.03 +/- 0.08, P <.0001). On multivariate analysis, Deltawall-motion score index predicted DeltaMPI (beta = 0.65, P <.0001) independently of age, sex, and the dobutamine-induced change in heart rate and systolic blood pressure. CONCLUSIONS: Data suggest that the change in MPI during LDDE may provide a simple and quantitative measure of overall left ventricular functional reserve in patients with a recent MI.  相似文献   
18.
Despite reports demonstrating the safety of laparoscopic donor nephrectomy (LDN) for pediatric recipients of renal transplants, recent evidence has challenged using LDN for recipients 5 years of age or younger. We retrospectively reviewed the records of all pediatric recipients of living donor renal transplants from September 2000 through August 2004. We compared those who received allografts recovered by LDN (n = 34) with those recovered by open donor nephrectomy (ODN, n = 26). Outcomes of interest included operative complications, postoperative renal function, the incidence of delayed graft function or episodes of acute rejection and long-term graft function. Donor and recipient demographic data were similar for the LDN and ODN groups. Serum creatinine and calculated creatinine clearance were not significantly different between groups both in the early postoperative period and at long-term follow-up (p > 0.142). Rates of delayed graft function and acute rejection did not differ between groups. Among recipients aged 5 years old or younger stratified by donor technique (9 LDN, 5 ODN recipients), no difference was noted in graft outcomes both early and long-term (p > 0.079). At our center, pediatric LDN recipients have graft outcomes comparable to those of ODN recipients. At experienced centers, we recommend continued use of LDN for pediatric recipients of all ages.  相似文献   
19.
OBJECTIVE: To evaluate the influence of gravidity on the results of in vitro fertilization (IVF)-embryo transfer (ET) cycles. PATIENTS AND METHODS: All consecutive women aged <35 years admitted to our IVF unit from January 2002 to December 2004 were enrolled in the study. Only patients undergoing one of their first three IVF cycle attempts were included. Gravidity, ovarian stimulation characteristics, number of oocytes retrieved, number of embryo transferred and clinical pregnancy rate were assessed. RESULTS: Three hundred and forty-two consecutive IVF cycles were evaluated. One hundred and sixty-one cycles were from nulligravidas and 181 from women with a history of at least one previous clinical pregnancy. Forty-eight (29.8%) clinical pregnancies were observed in the nulligravida group and 56 (30.9%) in the gravida group. There were no differences between nulligravidas and gravidas in causes of infertility, length of ovarian stimulation, peak estradiol and progesterone levels, number of oocytes retrieved, fertilization rate and number of embryos transferred. Gravidas were significantly older (30.4 vs. 27.6 years, p < 0.001) and used more gonadotropin ampoules (36.1 vs. 31.8, p < 0.004) compared with the nulligravidas. CONCLUSIONS: Patient gravidity has no influence on the likelihood of achieving pregnancy in IVF-ET cycles.  相似文献   
20.
This research is designed to evaluate a number of biological markers to estimate harmful exposure on coal miners from different mining regions in France and to relate the outcome to differences in prevalence of coal worker pneumoconiosis (CWP) between these regions. Eight epidemiological groups of active and ex-miners (smokers and non-smokers) have been selected in the French collieries (North, Lorraine and Provence) according to their occupational and pneumoconiotic status. The following biomarkers have been evaluated: cellularity of sputum, elementary analysis of particles in TEM/EDAX, plasma neutral metalloendo peptidase elastase type (NMEP), leucocyte elastase (HLE), fibronectin (FN) and elastin peptides. Pulmonary alveolitis, expressed by sputum cellularity, is different between active workers groups but not related to the general background of pneumoconiosis prevalence in the French collieries. In the plasma parameters, fibronectin, HLE and NMEP significantly increased in all groups of coal mine workers as compared to the control group, except for fibronectin parameter in Lorraine collierie. The degree of increase of these parameters allow us to discriminate the different groups and suggest that plasma FN, HLE and NMEP may be considered as biological markers of chronic inhalation of coal mine dust particles. The decrease of elastin peptides level in the Lorraine group alone suggests a specific alteration of elastin metabolism. These parameters were not related to the development of pneumoconiosis and its degree of severity.  相似文献   
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