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I Ramzan  V DeDonato 《Life sciences》1988,42(5):491-495
The purpose of this investigation was to determine whether the neurotoxicity of theophylline is altered in advanced pregnancy. Sprague-Dawley rats that were 20 days pregnant and nonpregnant rats of the same age and strain received infusions of aminophylline until onset of maximal seizures which occurred after 28 and 30 minutes respectively. Theophylline concentrations at this endpoint in serum (total) and CSF were similar but serum (free) and brain concentrations were slightly different in pregnant rats. Theophylline serum protein binding determined by equilibrium dialysis was lower in pregnant rats. Fetal serum concentrations at onset of seizures in the mother were similar to maternal brain and CSF concentrations and correlated significantly with the former. It is concluded that advanced pregnancy has a negligible effect on the neurotoxic response to theophylline in rats.  相似文献   
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A new stunt nematode, from soil around the roots of coconut (Cocos nucifera L.) and rice (Oryza sativa L.) from Karachi, Pakistan, is described and illustrated as Tylenchorhynchus qasimii n. sp. This new species is characterized by having females with 3–4 head annules, anteriorly directed stylet knobs, absence of post anal extension, presence of rounded sperm filled spermatheca and conoid to bluntly rounded hemispherical tail terminus. Males are common. Also included is the record of T. kegasawai from around the roots of rice (O. sativa L.), a new report from Sindh, Pakistan.  相似文献   
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A sensitive, rapid LC-MS/MS assay has been developed and validated for the simultaneous quantification of CPT-11 and its two principal metabolites, 7-ethyl-10-hydroxycamptothecin (SN-38), and 7-ethyl-10-[4-N-(5-aminopentanoic acid)-1-piperidino]carbonyloxy-camptothecin (APC) in human liver microsomal fractions and plasma. The method was linear over the ranges of 1.56-100 ng/mL, 3.13-150 ng/mL, and 0.78-100 ng/mL for CPT-11, SN-38, and APC, respectively. The total run time was 7.0 min. This assay offers advantages in terms of expediency, recovery of analytes, and suitability for the analysis of CPT-11 and its metabolites in various biological fluids.  相似文献   
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Two new olean-12-ene triterpenoids, camarolic acid (1) and lantrigloylic acid (2), have been isolated from the aerial parts of Lantana camara, along with ten known triterpenes, namely, camaric acid, lantanolic acid, lantanilic acid, pomolic acid, camarinic acid, lantoic acid, camarin, lantacin, camarinin, and ursolic acid. The new compounds have been characterized as 3,25-epoxy-3alpha-hydroxy-22beta-{[(S)-3-hydroxy-2-methylidenebutanoyl]oxy}olean-12-en-28-oic acid (1) and 3,25-epoxy-3alpha-hydroxy-22beta-[(3-methylbut-2-enoyl)oxy]olea-9(11),12-dien-28-oic acid (2) through spectroscopic studies and a chemical transformation. Seven of the constituents, namely pomolic acid, lantanolic acid, lantoic acid, camarin, lantacin, camarinin, and ursolic acid, were tested for nematicidal activity against root-knot nematode Meloidogyne incognita. Pomolic acid, lantanolic acid, and lantoic acid showed 100% mortality at 1 mg/ml concentration after 24 h, while camarin, lantacin, camarinin, and ursolic acid exhibited 100% mortality at this concentration after 48 h. These results are comparable to those obtained with the conventional nematicide furadan (100% mortality at 1 mg/ml concentration after 24 h).  相似文献   
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Five different varieties of Brassica napus (Cyclone, Dunkled, Oscar, Rainbow and KS75) were tested for their regeneration response. Cyclone showed a very high frequency of regeneration (92%). The use of silver nitrate was a pre-requisite for efficient shoot regeneration. Hypocotyls were selected as the starting material for transformation experiments on the basis of high transient GUS expression. Explants were co-cultivated with Agrobacterium strain EHA101 harboring a binary vector pIG121Hm containing neomycin phosphotransferase II (NPTII) gene, conferring resistance to kanamycin, hygromycin phosphotransferase (HPT) gene, conferring resistance to hygromycin as selectable markers and -glucuronidase (GUS) gene as a reporter. Acetosyringone promoted the transformation but was not an absolute requirement. A pre-selection period of 7 days after co-cultivation was essential for successful transformation. Kanamycin was efficient selective agent for selection and maximum transformation efficiency was 24%. GUS activity was evident in leaf tissues. All the transgenic plants have an expected band of 0.43 kb fragment by PCR analysis confirming the presence of foreign DNA into plant genome.  相似文献   
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The BRAF gene encodes for a serine/threonine protein kinase that participates in the MAPK/ERK signalling pathway and plays a vital role in cancers and developmental syndromes (RASopathies). The current review discusses the clinical significance of the BRAF gene and other members of RAS/RAF cascade in human cancers and RAS/MAPK syndromes, and focuses the molecular basis and clinical genetics of BRAF to better understand its parallel involvement in both tumourigenesis and RAS/MAPK syndromes—Noonan syndrome, cardio-facio-cutaneous syndrome and LEOPARD syndrome.  相似文献   
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The aim of present paper is to study the series solution of time dependent MHD second grade incompressible nanofluid towards a stretching sheet. The effects of mixed convection and thermal radiation are also taken into account. Because of nanofluid model, effects Brownian motion and thermophoresis are encountered. The resulting nonlinear momentum, heat and concentration equations are simplified using appropriate transformations. Series solutions have been obtained for velocity, temperature and nanoparticle fraction profiles using Homotopy Analysis Method (HAM). Convergence of the acquired solution is discussed critically. Behavior of velocity, temperature and concentration profiles on the prominent parameters is depicted and argued graphically. It is observed that temperature and concentration profiles show similar behavior for thermophoresis parameter Νt but opposite tendency is noted in case of Brownian motion parameter Νb. It is further analyzed that suction parameter S and Hartman number Μ depict decreasing behavior on velocity profile.  相似文献   
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