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51.
A study was done of the possible association between the development of common bile-duct stones and the presence of worms in rats experimentally infected with Fasciola hepatica. A total of 157 rats were individually infected with 20 metacercariae, and another 40 animals served as controls. The rats were dissected at 100, 200, 300, and 400 days postinfection (p.i.). A significant association was observed between the observation of stones and the presence of F. hepatica adults. The global frequency of bile-duct lithiasis in the parasitized rats was 22%, with a significantly lower incidence being observed in the younger group (100 days p.i.). Different analytical techniques were used to determine the main stone components. Energy-dispersive X-ray microanalysis showed calcium to be the main component in all cases (82–94%). Scanning electron microscopy, nuclear magnetic resonance ([1H]- and [13C]-NMR), and mass spectrometry revealed the predominance of palmitic (C-16) and stearic (C-18) acid. Received: 17 December 1999 / Accepted: 23 December 1999  相似文献   
52.
The impact of age and gender on Ochratoxin A (OTA) distribution in kidney and liver were studied. OTA was quantified in kidney and liver of young and mature rats of both sexes. Data was fit simultaneously using the population approach with NONMEM program. Fed and fasted mature males showed a 30% decrease and an 11% increase in relative bioavailability, respectively, in comparison with the rest of the groups. The OTA concentrations reached in kidney and liver were very similar between both organs. The models that best fit to data were the ones that considered that distribution of OTA to kidney and liver occurs from the central compartment and that elimination occurs mainly from the liver compartment. The kinetic analysis revealed that both, the apparent volume of distribution of the central compartment (V/F) and the apparent volume of distribution of the liver and kidney compartments (VL,K/F) increased significantly with body weight. Thus, the sex differences observed in organs distribution are a reflection of the differences in relative bioavailability observed in adult males, as a consequence of the fed and fasted conditions and to the significant higher body weight of mature males which directly affected the V/F and VL,K/F.  相似文献   
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54.
Body mass index (BMI) > 35‐40 kg/m2 is often a contraindication, while Roux‐en‐Y gastric bypass (RYGB) is performed to enable kidney transplantation. This single‐center retrospective study evaluated pre‐ and post‐transplant outcomes of 31 morbidly obese patients with end‐stage renal disease having RYGB before kidney transplantation between July 2009 and June 2014. Fourteen RYGB patients were subsequently transplanted. Nineteen recipients not having GB with a BMI ≥ 36 kg/m2 at transplantation were used as historical controls. Mean BMI (±SE) before RYGB was 43.5 ± 0.7 kg/m2 (range: 35.4‐50.5 kg/m2); 87.1% (27/31) achieved a BMI < 35 kg/m2. The percentage having improved diabetes/hypertension control was 29.0% (9/31); 25.8% (8/31) had complications (mostly minor) after RYGB. Among transplanted patients, blacks/Hispanics comprised 78.6% (11/14) and 84.2% (16/19) of RYGB and controls; 57.1% (8/14) and 63.2% (12/19) had a (mostly long‐standing) pretransplant history of diabetes. While biopsy‐proven acute rejection (BPAR) occurred significantly higher among RYGB vs control patients (6/14 vs 3/19, = .03), patients developing T‐cell BPAR were also significantly more likely to have a tacrolimus (TAC) trough level < 4.0 ng/mL within 3 weeks of T‐cell BPAR (= .0007). In Cox's model, the impact of having a TAC level < 4.0 ng/mg remained significant (= .007) while the effect of RYGB was no longer significant (= .13). Infections, graft, and patient survival were not significantly different. Despite obvious effectiveness in achieving weight loss, RYGB will need more careful post‐transplant monitoring given the observed higher BPAR rate.  相似文献   
55.
Invasive fungal infections have appeared to be increasingly emergent in immunocompromised patients, especially in solid organ transplant (SOT) recipients. The Alternaria genus encompasses more than 80 dematiaceus species. Among them, Alternaria alternata and Alternaria infectoria are the most frequent isolated as responsible for infection in humans.To our knowledge, we report the first case of a heart transplant recipient suffering from subcutaneous nodule caused by Alternaria infectoria and who was treated with isavuconazole. Despite all the promises of this new azole drug, one should keep in mind the potential great variability of the inter-individual responses for such complex patients. We demonstrate herein how it can be challenging to manage Alternaria infection in SOT recipients. More comprehensive studies and recommendations are expected in the context of Alternaria infections.  相似文献   
56.
57.
Five Spain(9V-3) Streptococcus pneumoniae strains were isolated from a patient with bronchiectasis who had received long-term ciprofloxacin therapy. One ciprofloxacin-susceptible strain was isolated before treatment, and four ciprofloxacin-resistant strains were isolated during treatment. The resistant strains were derived from the susceptible strain either by a parC mutation (low-level resistance) or by parC and gyrA mutations (high-level resistance). This study shows that ciprofloxacin therapy in a patient colonized by susceptible S. pneumoniae may select fluoroquinolone-resistant mutants.  相似文献   
58.
The purpose of this study was to examine the relationship of perceived field motion and human field rhythms to perceived health status, health conception, and well-being in early adolescents to determine which health-related variables are most compatible with Rogers' science of unitary human beings. The sample of 142 early adolescents responded to the study instruments in classrooms. The correlations between perceived field motion and each of the other variables were statistically significant, and increased in magnitude from perceived health status to health conception to well-being. These results give credence to Rogers' evolving philosophical belief that the term well-being is more compatible than health in her science.  相似文献   
59.
Two clinical isolates of viridans group streptococci (VS) with different degrees of susceptibility to optochin (OPT), i.e., fully OPT-susceptible (Opt(s)) VS strain 1162/99 (for which the MIC was equal to that for Streptococcus pneumoniae, 0.75 micro g/ml) and intermediate Opt(s) VS strain 1174/97 (MIC, 6 micro g/ml) were studied. Besides being OPT susceptible, they showed characteristics typical of VS, such as bile insolubility; lack of reaction with pneumococcal capsular antibodies; and lack of hybridization with rRNA (AccuProbe)-, lytA-, and pnl-specific pneumococcal probes. However, these VS Opt(s) strains and VS type strains hybridized with ant, a gene not present in S. pneumoniae. A detailed characterization of the genes encoding the 16S rRNA and SodA classified isolates 1162/99 and 1174/97 as Streptococcus mitis. Analysis of the atpCAB region, which encodes the c, a, and b subunits of the F(0)F(1) H(+)-ATPase, the target of optochin, revealed high degrees of similarity between S. mitis 1162/99 and S. pneumoniae in atpC, atpA, and the N terminus of atpB. Moreover, amino acid identity between S. mitis 1174/97 and S. pneumoniae was found in alpha helix 5 of the a subunit. The organization of the chromosomal region containing the atp operon of the two Opt(s) VS and VS type strains was spr1284-atpC, with spr1284 being located 296 to 556 bp from atpC, whereas in S. pneumoniae this distance was longer than 68 kb. In addition, the gene order in S. pneumoniae was IS1239-74 bp-atpC. The results suggest that the full OPT susceptibility of S. mitis 1162/99 is due to the acquisition of atpC, atpA, and part of atpB from S. pneumoniae and that the intermediate OPT susceptibility of S. mitis 1174/97 correlates with the amino acid composition of its a subunit.  相似文献   
60.
AIMS: To develop a model for simulations of processes in the oral glucose tolerance test (OGTT), using tools of the theory of dynamic systems. METHODS: Frequent sampling OGTT was performed in 13 healthy subjects (6 males and 7 females). Subsequently, employing glucose and insulin concentration-time profiles of the subjects, the model was developed. RESULTS: In all subjects the model was able to simulate influences of the insulin plasma concentration and gastric emptying rate on glucose concentration and to determine time profiles of glucose fractions retained in stomach. CONCLUSIONS: The approach presented represents an opportunity for building models for data analyses in OGTT.  相似文献   
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