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181.
It is of interest to compile available information on the root canal morphology of primary maxillary molars from known literature. The literature resources used to collect data include Medline/PubMed, The Cochrane Central Register of Clinical Trials, SIGLE and Science Direct. Data consists of type of population, number of teeth per study, number of root canals, canal length and type of root canal configuration. We used data from a total of 13 studies (951 primary maxillary molars). Maxillary molars (1st and 2nd) are dominant for two roots variant. The first molar the mean root length ranges from 7.9mm - 8.1mm. The second molar ranges from 7.2mm-8.5mm. Type I (explain in a phrase) canal morphology is the common variant in both the molars. Data shows that Root Canal morphology shows variations with the diagnostic aid (example micro CT) used and in different ethnic populations.  相似文献   
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Bacteriocin jenseniin G is detected typically in 50-fold concentrated 10 d cultures of the producer, Propionibacterium thoenii ( jensenii ) P126 at low concentrations (32–64 AU ml−1). The effect of pH on production was examined by growing the producer in sodium lactate broth, both statically and in stirred fermenters, with or without pH control. Activity was detected in unconcentrated static producer cultures at day 7 through to day 14. Maximal jenseniin G activity (21 AU ml−1) was observed in concentrated supernates at day 9, remaining relatively constant through to day 14. Producer cultures grown in stirred fermenters without pH control yielded detectable activity in 50-fold concentrated supernates at day 3 and maximal activity at day 11. Producer growth in stirred fermenters at controlled pH yielded maximum production at pH 6·40 and maximum activity (160 AU ml−1) at day 13. Jenseniin G activity at pH 6·40 represented a fivefold increase over previous reports. Medium pH was critical to jenseniin G production.  相似文献   
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Here we synthesized four novel indole conduritol derivatives 1–4 for the first time in the literature and probed their biological activities with the α and β-glucosidases. The compounds showed quite effective glucosidase inhibitory action. IC50 values of the compounds were compared with the known glucosidase inhibitor acarbose and it was determined that newly synthesized indole conduritols had more powerful effect against β-glucosidase in addition to exhibiting moderate influence against α-glucosidase. Our molecules thus constitute an important starting point for the design and exploitation of novel glucosidase inhibitors since glucosidase inhibitors have widespread applications in the treatment of diabetes, viral infections, lysosomal storage diseases and cancers.  相似文献   
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All extant species in the Rhinocerotidae family are experiencing escalating threats in the wild, making self-sustaining captive populations essential genetic reservoirs for species survival. Assisted reproductive technologies (ARTs) will become increasingly important for achieving and maintaining ex situ population sustainability and genetic diversity. Previous reports have shown that a large proportion of captive southern white rhinoceros (SWR) females are irregularly cyclic or acyclic, and that cycling females display two different estrous cycle lengths of approximately 30 or 70 days. It has been suggested that the longer estrous cycle length is infertile or subfertile, as no term pregnancies have been observed following long cycles. Here we report the achievement of two pregnancies following long luteal phases, using ovulation induction and artificial insemination with either fresh or frozen-thawed semen. One female SWR conceived on the first insemination attempt and gave birth to a live offspring. A second female conceived twice in consecutive long cycles although the first embryo was resorbed by 33 days post-insemination. A pregnancy from this female's second insemination is ongoing with expected parturition in November 2019. Whether prolonged estrous cycles in SWR are subfertile or infertile in natural breeding situations remains unclear. However, our findings demonstrate that the application of ARTs following prolonged cycles can result the successful establishment of pregnancies in SWR. Therefore, with ARTs, female SWR otherwise considered nonreproductive due to long estrous cycles may still have the potential for representation and contribution to the ex situ population.  相似文献   
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Osteoblasts play an important role in bone regeneration and repair. The hypoxia condition in bone occurs when bone undergoes fracture, and this will trigger a series of biochemical and mechanical changes to enable bone repair. Hence, it is interesting to observe the metabolites and metabolism changes when osteoblasts are exposed to hypoxic condition. This study has looked into the response of human osteoblast hFOB 1.19 under normoxic and hypoxic conditions by observing the cell growth and utilization of metabolites via Phenotype MicroArrays™ under these two different oxygen concentrations. The cell growth of hFOB 1.19 under hypoxic condition showed better growth compared to hFOB 1.19 under normal condition. In this study, osteoblast used glycolysis as the main pathway to produce energy as hFOB 1.19 in both hypoxic and normoxic conditions showed cell growth in well containing dextrin, glycogen, maltotriose, D-maltose, D-glucose-6-phospate, D-glucose, D-mannose, D-Turanose, D-fructose-6-phosphate, D-galactose, uridine, adenosine, inosine and α-keto-glutaric acid. In hypoxia, the cells have utilized additional metabolites such as α-D-glucose-1-phosphate and D-fructose, indicating possible activation of glycogen synthesis and glycogenolysis to metabolize α-D-glucose-1-phosphate. Meanwhile, during normoxia, D-L-α-glycerol phosphate was used, and this implies that the osteoblast may use glycerol-3-phosphate shuttle and oxidative phosphorylation to metabolize glycerol-3-phosphate.  相似文献   
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Parkinson's disease is characterized by progressive cell death in the substantia nigra pars compacta, which leads to dopamine depletion in the striatum and indirectly to cortical dysfunction. Increased glutamatergic transmission in the basal ganglia is implicated in the pathophysiology of Parkinson's disease and glutamate receptor mediated excitotoxicity has been suggested to be one of the possible causes of the neuronal degeneration. In the present study, the effects of serotonin, gamma-aminobutyric acid and bone marrow cells infused intranigrally to substantia nigra individually and in combination on unilateral 6-hydroxydopamine induced Parkinson's rat model was analyzed. Scatchard analysis of total glutamate and NMDA receptor binding parameters showed a significant increase in Bmax (P < 0.001) in the cerebral cortex of 6-hydroxydopamine infused rat compared to control. Real Time PCR amplification of NMDA2B, mGluR5, bax, and ubiquitin carboxy-terminal hydrolase were up regulated in cerebral cortex of 6-hydroxydopamine infused rats compared to control. Gene expression studies of GLAST, ά-Synuclien and Cyclic AMP response element-binding protein showed a significant (P < 0.001) down regulation in 6-OHDA infused rats compared to control. Behavioural studies were carried out to confirm the biochemical and molecular studies. Serotonin and GABA along with bone marrow cells in combination showed reversal of glutamate receptors and behaviour abnormality shown in the Parkinson's rat model. The therapeutic significance in Parkinson's disease is of prominence.  相似文献   
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