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591.
In Vitro Cellular & Developmental Biology - Plant - Foetid juniper (Juniperus foetidissima Willd.) is one of the most important coniferous species faced with multiple threats and it is...  相似文献   
592.
Hosseini  Soodeh 《Cluster computing》2021,24(2):1199-1215
Cluster Computing - Devising appropriate defense strategies against malware propagation in complex networks with minimal budget is a challenging problem in research community. This paper studies...  相似文献   
593.
In vitro growth of preantral follicles has the potential to produce considerable numbers of competent oocytes for use in medicine, agriculture, and even wildlife conservation. The critical regulatory role of growth factors and hormones in the development of preantral follicles has been established. This study investigated the effect of glial‐derived neurotropic factor (GDNF) and kit ligand (KL) on the in vitro development of ovine preantral follicles. Results indicated that both GDNF and KL significantly improved activation of primordial follicles, similar to co‐addition of epidermal growth factor (EGF) and basic fibroblast growth factor (bFGF), which are commonly used for in vitro follicular development. Importantly, GDNF had a more profound effect on follicle health, development, and differentiation compared with KL alone. Furthermore, the combination of GDNF and KL in the presence of EGF and bFGF had a positive, synergic effect on health, development, and differentiation of preantral follicles, as determined by histological and hormonal assessments. The results of this study may provide a foundation for further studies that will unravel the molecular mechanisms of follicular development to further improve the current status of in vitro preantral follicle culture. Mol. Reprod. Dev. 80: 35–47, 2013. © 2012 Wiley Periodicals, Inc.  相似文献   
594.
Despite encouraging advances in fertility technology, the success rate of an ongoing pregnancy is relatively low and predominantly associated with implantation failure. Inflammatory responses are beneficial in the fetomaternal interface and supposedly accelerate the chances for successful implantation. The current study aims to determine the effect of Toll-like receptor 4 (TLR4) overexpression in mouse blastocysts via Let-7a downregulation using intracytoplasmic sperm injection-sperm-mediated gene transfer on embryo attachment rate. The pLenti-III-GFP-miR-Off-Let-7a vector was transmitted to oocytes derived via in vitro maturation (IVM) and in vivo oocytes by using NaOH-treated spermatozoa. Let-7a and TLR4 expression levels were evaluated by quantitative real-time polymerase chain reaction (qRT-PCR), immunocytochemistry, and western blot analysis in both oocytes and embryos. Blastocyst adhesion on the endometrial cells was monitored by microscopic analysis. qRT-PCR results showed that Let-7a expression decreased in the IVM (GV-MII) oocytes compared to the in vivo oocyte (MII) group (p < .05). TLR4 showed a higher expression in GV-MII oocytes at both the gene and protein levels (p < .05). Following anti-miR-Let-7a transmission, the TLR4 expression level was significantly upregulated in embryos compared with the control groups (p < .05). Attachment and migration of trophoblasts cells towards endometrial cells dramatically increased compared to the control group (p < .05). Based on our results, we concluded that Let-7a might mediate embryo attachment through regulation of TLR4 expression levels.  相似文献   
595.
Liver transplantation (LT) is a potentially curative treatment for terminal stage hepatic diseases. Bacterial infections are the main causes of mortality and morbidity in the early period after LT. Identifying the risk factors could help in minimizing their development. We prospectively investigated the incidence, characteristics, and risk factors of bacterial infections among the recipients during hospitalization after LT and assigned a predictive score. All 389 consecutive adults who underwent LT at the main referral hospital of LT in Iran during 1 year were enrolled prospectively in a cohort study. Infection group consisted of 143 recipients (36.8%). Urinary tract and surgical site infections were the most frequent ones. Gram-negative bacteria were more prevalent than Gram-positive ones. Independent risk factors were female sex (relative risks = 2.13), age ≤ 43.5 years (3.70), hospital stay ≥ 9.5 days (5.22), abdominal reoperation (3.03), vancomycin-resistant Enterococci colonization (5.52), hospitalization 3 months prior to LT (3.25), mechanical ventilation ≥48 hr (4.93), and renal replacement therapies (13.40). We developed a risk score for the prediction of bacterial infections with an area under the receiver operating characteristic curve of 0.85 (95% CI, 0.81–0.89) with sensitivity of 88% and specificity of 64%. In the infection group, mortality was higher than in controls (18.9% vs. 2.0%) with longer hospitalization (16 vs. 10 days; P < 0.001). We detected a high rate of bacterial infections leading to longer hospital stay and higher mortality rate. The formulated risk score can help predict bacterial infections; however, it requires clinical validation in further studies.  相似文献   
596.

One of the main effluents from fishmeal plants is stickwater (STW) that causes a considerable number of environmental hazards. This study aimed to replace standard growth medium (F/2; as an enriched solution for growing most of the marine microalgae) of Tetraselmis suecica with different ratios of STW from a kilka fishmeal plant including 0% (control), 10%, 25%, 50%, 75%, and 100%. Results showed that the highest nutrient removal efficacy was obtained in 75% STW treatment, followed by the highest algal cell density (1.23 × 107 cells mL?1) (P <0.05). A significant increase in the concentrations of photosynthetic pigments (chlorophyll a, b) and lipid productivity was recorded in 75% STW treatment compared to others (P <0.05). The maximum contents of carotenoids and crude protein were obtained in 100% and 50% STW groups, respectively. The levels of saturated and monosaturated fatty acids were significantly increased by increasing the inclusion ratio of STW from 50 to 100% (P <0.05). However, the lowest level of polyunsaturated fatty acids was measured in 100% STW treatment. Overall, replacing F/2 with STW up to 75% is feasible to culture T. suecica with the highest biomass and lipid productivity.

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597.
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