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841.
The Middle Eocene (Lutetian) strata constituting the top of the Subathu Formation in Jammu and Kashmir, have yielded a large number of ziphodont crocodilians. The affinity of these serrated-toothed crocodiles has been assigned to the Eusuchian Pristichampsus rather than to the Sebecosuchia. The teeth are morphologically diverse, strongly fluted with serrations varying from fine to coarse. It is believed that the Kashmir ziphodont crocodiles are migrant descendants of Chinese forms which spread across the Indian sub-continent. Their presence in Europe may be accounted by migration along with Asiatosuchus across the Turgai Straits sometime in the Early Eocene.  相似文献   
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Synaptic tagging and capture (STC) and cross-tagging are two important mechanisms at cellular level that explain how synapse-specificity and associativity is achieved in neurons within a specific time frame. These long-term plasticity-related processes are the leading candidate models to study the basis of memory formation and persistence at the cellular level. Both STC and cross-tagging involve two serial processes: (1) setting of the synaptic tag as triggered by a specific pattern of stimulation, and (2) synaptic capture, whereby the synaptic tag interacts with newly synthesized plasticity-related proteins (PRPs). Much of the understanding about the concepts of STC and cross-tagging arises from the studies done in CA1 region of the hippocampus and because of the technical complexity many of the laboratories are still unable to study these processes. Experimental conditions for the preparation of hippocampal slices and the recording of stable late-LTP/LTD are extremely important to study synaptic tagging/cross-tagging. This video article describes the experimental procedures to study long-term plasticity processes such as STC and cross-tagging in the CA1 pyramidal neurons using stable, long-term field-potential recordings from acute hippocampal slices of rats.  相似文献   
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The present study was undertaken to investigate the protective effect of Indian honey on acetaminophen induced oxidative stress and liver damage in rat. Honey serves as a source of natural medicine, which is effective to reducing the risk of heart disease, liver toxicity and inflammatory processes. The hepatoprotective activity of the Indian honey was determined by assessing levels of Serum transaminases, ALP and total bilirubin. Finally, the effects of the test substances on the antioxidant enzymes of the liver were also studied by assessing changes in the level of reduced glutathione, glutathione peroxidase, catalase and superoxide dismutase. Serum transaminase, ALP and total bilirubin level were significantly elevated and the antioxidant status in liver such as activities of SOD, CAT, GPx and the levels of GSH were declined significantly in APAP alone treated animals. Pretreatment with honey and silymarin prior to the administration of APAP significantly prevented the increase in the serum levels of hepatic enzyme markers and reduced oxidative stress. The histopathological evaluation of the livers also revealed that honey reduced the incidence of liver lesions induced by APAP. Results suggest that the Indian honey protects liver against oxidative damage and it could be used as an effective hepatoprotector against APAP induced liver damage.  相似文献   
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Summary Characterization of sinefungin related antifungal antibiotics from fermentation broth was accomplished by coupling photodiode array (PDA) detection to high performance liquid chromatography (HPLC). From the combined HPLC-PDA evaluation of broth filtrate, we detected five sinefungin related components. Fast atom bombardment (FAB) mass spectroscopic evaluations, mass-analysed ion kinetic energy spectra (MIKES) and collision activated (CA) MIKES of these components confirmed their respective identities. Our findings from the combination of HPLC photodiode array acquisition and FAB-mass spectrometry suggest we have detected the presence of a previously unreported sinefungin analogue.  相似文献   
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Background. Helicobacter pylori is associated with chronic active gastritis and peptic ulceration (PU). Omeprazole is a proton pump inhibitor that is effective in healing PU and reducing gastritis. Previously it has been found that omeprazole has some bacteriostatic activity against H. pylori both in vitro and in vivo and in inhibiting urease activity in vitro. Our aim was to evaluate the effect of omeprazole on H. pylori colonization of the gastric mucosa, urease activity in vivo, and the presence of associated gastritis in patients with duodenal ulcer (DU).
Materials and Methods. We studied 12 patients (7 men and 5 women, ages 22–68 yr) with Du larger than 5 mm in diameter with a positive CLOtest (Delta West Ltd., Australia). Omeprazole, 20 mg bid, was given for 8 weeks to each patient, patients were endoscoped at the end of this period to check for healing of DU, and repeat biopsies were obtained from the gastric antrum for histologyical analysis, CLOtest, and culture.
Results. DU healed completely in all patients. Likewise in all patients there was significant reduction in the urease activity, from 22.1=4.17 to 1.58 ± 0.92 units/ml ( p <.001; 95% confidence interval of the difference between means, 32.7–14.1), and reduced H. pylori density, from 1,403.46 ± 128.23 to 422.5 ± 172.39 colony-forming units (CFU) per milligram of tissue biopsy ( p < .001; 95% confidence interval of the difference between means, 1,486.1–590.5). The numbers of H. pylori were reduced on the gastric mucosa after omeprazole therapy and disappeared in six patients, a result that correlated with a negative CLOtest reading after 24 hours.
Conclusion. Omeprazole, 20 mg bid, is capable of reducing H. pylori numbers and urease activity in vivo. There was no significant reduction in the severity of antral gastritis in DU patients studied.  相似文献   
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