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651.
This study retrospectively evaluated the histopathological criteria commonly used in the literature on the diagnosis of hydatidiform mole, in correlation with the diagnosis rendered previously. The molar and non-molar cases seen in the first-trimester of pregnancy were separately reviewed by two pathologists. The correlation between the consensual histological diagnosis and the ploidy status was then evaluated.We retrospectively studied 89 specimens of abortus conception, including 35 complete hydatidiform moles (CHM), 12 partial hydatidiform moles (PHM), and 42 hydropic abortions (HA).The final histopathological diagnosis was compared with the results of DNA content detected by imaging analyzer (Samba 200), studying all cases of molar pregnancy and 4 cases of HA (initially diagnosed as molar pregnancies).In the consensus histological diagnosis, the cases were reclassified as follows: 30 CHM (initial diagnosis (ID): 27 CHM and 3 PHM), 12 PHM (ID: 6 PHM and 6 CHM), and one case with a persistent problem in differentiating PHM from HA and 46 HA (ID: 42 HA, 2 CHM, and 2 PHM).An agreement between the two pathologists was reached in 77 cases (K=0.72, 0.52, and 0.9, respectively, for CHM, PHM, and HA).The ploidy study demonstrated diploidy in 56.6% (17/30) of CHM and triploidy in 58.3% (7/12) of PHM. In the 4 cases of HA studied, 3 were diploid and 1 case was aneuploid.Our study demonstrated that several histopathological criteria could be used for the distinction between PHM, CHM, and HA. However, the study of DNA cannot be the technique of choice to distinguish between these entities. Some cases remain problematic since the morphological criteria are not easily reproducible. New sensitive techniques might resolve these dilemmas.  相似文献   
652.
This study was conducted to identify the β-lactamase content of 30 metallo-β-lactamase-producing Pseudomonas aeruginosa isolated in 2007 from two Tunisian hospitals and to investigate their genetic relatedness. All these isolates produced VIM-2. bla(PER-1), bla(PSE-1), bla(OXA-2), and bla(OXA-10) were identified in 17, 5, 21, and 1 isolates, respectively. These enzymes were often associated in the same isolate: 26 isolates had at least two β-lactamases. The predominant serotype was O12. Pulsed-field gel electrophoresis revealed genetic diversity among the metallo-β-lactamase-producing P. aeruginosa isolates. This is the first report on the existence of bla(PER-1), bla(PSE-1), bla(OXA-2), and bla(OXA-10) in Tunisia.  相似文献   
653.
Background/aimsThe role of methylenetetrahydrofolate reductase (MTHFR) and angiotensin-converting enzyme (ACE) gene polymorphisms as being risk factors for diabetes is still controversial. The aim was to investigate the distribution of ACE and MTHFR genotypes as well as to evaluate the role of plasmatic total homocysteine levels (tHcy) and ACE activity in Tunisian patients with type 2 diabetes mellitus (T2DM).Design and methods115 T2DM patients compared to 116 healthy volunteers.ResultsThe ACE I/D polymorphism was significantly associated with diabetes (p < 0.0001). The DD genotype and D allele were more frequent in patients compared to control group [DD: OR = 4.93; p < 0.0001; 95 % CI: 2.71–8.97; D: OR = 3.08, 95% CI: 2.09–4.51 p < 0.0001]. MTHFR allele and genotype frequencies did not differ between patients and controls. The susceptibility to diabetes in individuals with genotypes DD +vTT was 13.39 and in the individuals with DD + CT was 6.57 times that of the controls. However, individuals with genotypes ID + CC or II + CT have a protective effect against diabetes. The DD and TT genotypes were associated with significantly higher ACE activity and tHcy levels in diabetics.ConclusionOur data suggest that ACE ID polymorphism may act synergistically with MTHFR C677T polymorphism to assess diabetes risk.  相似文献   
654.
Objectives: This study aimed to estimate the prevalence of liver fibrosis and assess the risk factors for developing significant liver fibrosis in patients with Thalassemia Major (TM).

Methods: All patients with TM over the age of 10 years were included in the study.

Results: A total of 94 eligible patients underwent 2-D SWE. The median age was 26.7 years. The median of the average 5-year serum ferritin (5yrSF) and liver iron concentration (LIC) assessed by MRI T2* were 1326?µg/L and 6.7?mg/g?dw, respectively. Hepatitis C and hepatitis B core antibodies were positive in 38% and 1% of the patients respectively. The proportion of patients with significant fibrosis was 60%. Male gender increased the risk of significant fibrosis (Odds ratio of 0.4; p?=?.0373). Additionally, the 5yrSF (p?=?.00661), the LIC (p?=?.0225) and the lowest LIC of the previous 5 years (p?=?.0211) were significant. In the multivariable logistic regression model, only 5yrSF (p?=?.0035) and gender (p?=?.00984) remained significant.

Conclusions: The risk of liver fibrosis is associated with iron overload and gender in patients with TM.  相似文献   
655.
The gene encoding β-galactosidase from dairy Streptococcus thermophilus strain LMD9 was cloned, sequenced and expressed in Escherichia coli. The recombinant enzyme was purified and showed high specific activity of 464 U/mg. This protein displays a homotetrameric arrangement composed of four 118 kDa monomers. Monitoring of the activity showed that this enzyme was optimally active at a wide range of temperatures (25–40 °C) and at pH from 6.5 to 7.5. Immobilization of the recombinant E. coli in alginate beads clearly enhanced the enzyme activity at various temperatures, including 4 and 50 °C, and at pH values from 4.0 to 8.5. Stability studies indicated that this biocatalyst has high stability within a broad range of temperatures and pH. This stability was improved not only by addition of 1 mM of Mn2+ and 1.2 mM Mg2+, but essentially through immobilization. The remarkable bioconversion rates of lactose in milk and whey at different temperatures revealed the attractive catalytic efficiency of this enzyme, thus promoting its use for lactose hydrolysis in milk and other dairy products.  相似文献   
656.
657.
Background

In the postpandemic era, wearing protective masks in public places will still be an important means of blocking popular viruses in the future. The purpose of this study was to explore whether sports performance was affected by mask wearing and exercise duration during 15-min treadmill running at a speed of 75% maximal aerobic speed.

Methods

Thirty-six males were randomly divided into mask and nonmask groups. The kinematic and kinetic data were obtained at four time points (RN0–1 min, RN5–6 min, RN9–10 min, and RN14–15 min) during running. Two-way mixed ANOVA was applied to examine the effects between groups and times with Bonferroni post hoc comparison and independent samples t-test.

Results

The results showed that there was no difference between mask and nonmask group during running (p?>?0.05). As running time increased, hip joint ROM, hip joint flexion/extension max, and ankle joint plantarflexion max angles increased; knee joint flexion min and ankle joint dorsiflexion max angles decreased; average peak vertical ground reaction forces (PVGRF) increased after 9 min-running (p?<?0.05).

Conclusions

Wearing a medical protective mask does not affect the joint angle and touchdown PVGRF of lower extremities during treadmill running while affected by running time and changed after 9 min-treadmill running. Future studies will examine the effects of wearing masks during the pandemic on muscle activation and blood biochemical values during exercise.

Trial registration No. ChiCTR2000040535 (date of registration on December 1, 2020). Prospectively registered in the Chinese Clinical Trial Registry.

  相似文献   
658.
This research work presents an optimal energy management for a hybrid water pumping system driven by a photovoltaic generator (PVG) and a wind turbine. These two renewable energies are used as power generation sources, whereas a battery is added as an energy-storing system, for the purpose of controlling the power flow and providing a constant load supply. The proposed management system, serve to guarantee the pumping system autonomy in a rural region where's no access to the electrical network. As a result, a maximum power point tracking (MPPT) controller is created based on the fuzzy Takagi–Sugeno (TS) model, ensuring maximum power transfer to the moto-pump in spite of wind speed and insolation changes. The synthesis of MPPT control law involves TS fuzzy reference models which generate the desired trajectories to track. A supervisor has been developed for energy management and its major purpose is to effectively use the battery to satisfy the power load requirements, and that is by maintaining the state of charge (SOC) to extend the battery's life. Finally, simulation results have been done based on Matlab/Simulink with the aim of validating the efficiency of the proposed energy management supervisor.  相似文献   
659.
Schwannoma is a type of nerve tumor of the nerve sheath. They are preferentially localized on the head, neck, and flexor surfaces of the extremities. Retroperitoneal schwannoma is extremely rare. The diagnosis is uncommon and based on the anatomopathological and immunochemistry examination of the surgical specimen. We herein report an uncommon location of schwannoma treated with conventional surgery in a 53‐year‐old female patient admitted to our department for chronic abdominal pain. Retroperitoneal schwannoma is a rare disease that occurs in adult females. The histopathological examination is the only reliable examination for the diagnosis after total surgical resection.  相似文献   
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