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1.
Optimization of cellulase production by Penicillium occitanis   总被引:1,自引:0,他引:1  
The mutant Pol6 of Penicillium occitanis is an interesting strain for producing cellulases and hemicellulases. The nitrogen source and substrate that regulate cellulase production were evaluated in shake-flask and fermentor (batch and fed-batch) culture. The nature of the nitrogen source and the C/N ratio markedly affected cellulase production by P. occitanis. When nitrate was used in Mandels and Weber's basal growth medium with a C/N ratio below 20.2, it resulted in more cellulase production than from urea or ammonium sulphate. Crude substrates such as wheat bran and wheat flour residues, used in combination with a local cellulose esparto grass paper pulp as an alternative nitrogen source and cellulose substrates, also gave high cellulase yields. Greatest cellulase yields and productivity were obtained by fed-batch cultivation [23 filter-paper activity units (FPU)/ml and 168 FPUI–1h–1].  相似文献   
2.

Purpose

Erectile dysfunction is one of the most frequent complications in diabetes and also the most often under diagnosed. We report the prevalence of erectile dysfunction in 200 diabetic patients.

Patients and methods

Prevalence was estimated by the French version of the International Index of Erectile Function 5 (IIEF5).

Results

146 patients were included. Erectile dysfunction concerned 74 patients; a severe form was observed in 21.6%, a moderate in 37.8% and a mild one in 40.6%. The patients who presented erectile dysfunction were significantly older and displayed longer duration of diabetes.

Conclusion

Erectile dysfunction is frequent and severe among diabetic patients. The medical staff plays an essential role to initiate early diagnosis, promote psychological support and provide medication, when possible.  相似文献   
3.
Response surface methodology was used to optimize pectin recovery from lemon by-product using an acidified date juice as extraction solution. When enriched in pectin, this latter can be useful for preparation of date-lemon jelly. The effects of three parameters namely temperature, pH and extraction time, on pectin extraction were studied. The fitted mathematical model allowed us to plot response surfaces as well as isoresponse curves and to determine optimal extraction conditions. Results clearly indicated that the temperature was the main factor influencing the pectin yield which increased with temperature and time or decreasing pH. The selected optimal conditions were: temperature 84.34 °C; extraction time 3 h 34 min and pH 2.8. These conditions yielded about 11.21% of pectin versus 10.89% for the predicted value.  相似文献   
4.
To compare the effects of two nap opportunities (20 and 90 min) to countermeasure the transient naturally occurring increased sleepiness and decreased performances during the post-lunch dip (PLD). Fourteen highly trained judokas completed in a counterbalanced and randomized order three test sessions (control (No-nap), 20- (N20) and 90-min (N90) nap opportunities). Test sessions consisted of the running-based anaerobic sprint test (RAST), simple and multiple-choice reaction times (MCRT) and the Epworth sleepiness scale (ESS). From the RAST, the maximum (Pmax), mean (Pmean) and minimum (Pmin) powers were calculated. Blood samples were taken before and after the RAST to measure the effect of pre-exercise napping on energetic and muscle damage biomarkers and antioxidant defense. N20 increased Pmax and Pmean compared to No-nap (p < 0.001, d = 0.59; d = 0.66) and N90 (p < 0.001, d = 0.98; d = 0.72), respectively. Besides, plasma lactate and creatinine increased only when the exercise was performed after N20. Both N20 (p < 0.001, d = 1.18) and N90 (p < 0.01, d = 0.78) enhanced post-exercise superoxide dismutase activity compared to No-nap. However, only N20 enhanced post-exercise glutathione peroxidase activity (p < 0.001, d = 1.01) compared to pre-nap. Further, MCRT performance was higher after N20 compared to No-nap and N90 (p < 0.001, d = 1.15; d = 0.81, respectively). Subjective sleepiness was lower after N20 compared to No-nap (p < 0.05, d = 0.92) and N90 (p < 0.01, d = 0.89). The opportunity to nap for 20 min in the PLD enhanced RAST, MCRT performances, and antioxidant defense, and decreased sleepiness. However, the opportunity of 90 min nap was associated with decreased repeated sprint performances and increased sleepiness, probably because of the sleep inertia.  相似文献   
5.
The fate of hematopoietic stem and progenitor cells (HSPCs) is regulated by their interaction with stromal cells in the bone marrow. However, the cellular mechanisms regulating HSPC interaction with these cells and their potential impact on HSPC polarity are still poorly understood. Here we evaluated the impact of cell–cell contacts with osteoblasts or endothelial cells on the polarity of HSPC. We found that an HSPC can form a discrete contact site that leads to the extensive polarization of its cytoskeleton architecture. Notably, the centrosome was located in proximity to the contact site. The capacity of HSPCs to polarize in contact with stromal cells of the bone marrow appeared to be specific, as it was not observed in primary lymphoid or myeloid cells or in HSPCs in contact with skin fibroblasts. The receptors ICAM, VCAM, and SDF1 were identified in the polarizing contact. Only SDF1 was independently capable of inducing the polarization of the centrosome–microtubule network.  相似文献   
6.

Purpose

To define epidemiological, clinical, therapeutic and prognostic factors influencing survival of breast cancer in young women younger than 35 in southern Tunisia.

Material and methods

This is a retrospective study of 83 patients younger than 35 years and treated within tumors mammary committee of Sfax.

Results

The mean age was 31.7 years. T2 stage, high grade with positive node tumors were frequent. Breast surgery was performed for 73 patients. Chemotherapy was neo-adjuvant, adjuvant and palliative for respectively 10, 62 and 13 patients. Radiotherapy was delivered for 65 patients with curative intent and for 8 metastatic patients. Endocrine therapy was adjuvant in 38 patients and palliative in 6 cases. The overall survival (OS) at 5 years was 66.8%. Pejorative prognostic factors in uni-variate analysis were clinical T stage (T3, T4), and the number of involved lymph nodes.

Conclusion

Despite adequate treatment, the prognosis of breast cancer in young women remains worse. Early diagnosis is necessary to promote outcome.  相似文献   
7.
Conjunctival lesions of ocular myiasis are common in the mediterranean region. The authors report 23 cases of conjunctival myiasis. This affection is caused by fly's larvae: Oestrus ovis presenting typically with inflamed and oedematous eyes. We diagnose the affection by directly showing the larvae on conjunctiva. The treatment consisted to extirpate larvae one by one.  相似文献   
8.
This letter investigates the MHD three-dimensional flow of upper-convected Maxwell (UCM) fluid over a bi-directional stretching surface by considering the Cattaneo-Christov heat flux model. This model has tendency to capture the characteristics of thermal relaxation time. The governing partial differential equations even after employing the boundary layer approximations are non linear. Accurate analytic solutions for velocity and temperature distributions are computed through well-known homotopy analysis method (HAM). It is noticed that velocity decreases and temperature rises when stronger magnetic field strength is accounted. Penetration depth of temperature is a decreasing function of thermal relaxation time. The analysis for classical Fourier heat conduction law can be obtained as a special case of the present work. To our knowledge, the Cattaneo-Christov heat flux model law for three-dimensional viscoelastic flow problem is just introduced here.  相似文献   
9.
Acute and 90‐day subchronic oral toxicity studies were conducted to establish the safety evaluation of xylanases preparations. A potential oxidative stress evaluation was also performed through testing the generation of oxidative radicals, depletion of antioxidants via oxidative modification of lipids, proteins and DNA of organ cells. During the subchronic oral toxicity study, no mortality was observed, obvious treatment‐related clinical signs and urinalysis parameters were in normal range. Differences in some hematological parameters, biochemistry, relative organ weight, and histopathology examinations between the treated group and the control group were not judged to be adverse. Our results indicated that the no‐observed‐adverse‐effect level for xylanases was 1,500 TXU/kg/day and the plasma antioxidant assays showed that these xylanases did not produce free‐radicals nor oxidative injuries. On the basis of the bacterial reverse mutation assay data, it is concluded that the expressed xylanase in Pichia pastoris do not present any mutagenic potential when tested in relevant genotoxicological assays.  相似文献   
10.
Subtelomeric rearrangements significantly contribute to idiopathic mental retardation and result in several mental retardation syndromes; however, most subtelomeric defects lack a characteristic phenotype. Thirty patients with unexplained mental retardation, a normal R banded karyotype at the 550 band, and no clinically recognizable syndrome were screened by Multiplex ligation-dependent probe amplification (MLPA). Four anomalies were identified: deletion 17q, duplications (4q), and associated duplications 15q and Xq. This duplication was found in two sisters of the proband. Anomalies were unidentified by the conventional technique. The prevalence of subtelomeric imbalances in our cohort of moderate to severe mental retardation is around 13% and is consistent with the literature. The sensitivity of the MLPA technique was characterized on cytogenetically verified positive and negative controls. MLPA is a fast, reliable, and relatively inexpensive technique to detect subtelomeric rearrangement in comparison with the fluorescence in situ hybridization (FISH) technique.  相似文献   
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