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161.
We describe an uncommon case of typical flutter with symptomatic sinus node dysfunction, in which a permanent junctional rhythm developed following ablation of the cavo-tricuspid isthmus. This rhythm activated the right atrium in counter clockwise manner thus providing spontaneous proof of unidirectional isthmus block, a phenomenon that is usually demonstrated by proximal coronary sinus pacing.  相似文献   
162.
Active targeting of drug molecules can be achieved by effective attachment of suitable ligands to the surface of carriers. The present work was attempted to prepare mannosylated gelatin microspheres (m-GMs) so as to achieve targeted delivery of isoniazid (INH) to alveolar macrophages (AMs) and maintain its therapeutic concentration for prolonged period of time. Microspheres were prepared by emulsification solvent extraction method and evaluated for physicochemical characteristics, drug release, ex vivo drug uptake by AMs and pharmacokinetic characteristics. Fourier transform infrared spectroscopy and nuclear magnetic resonance spectral analysis confirmed that mannosylation took place through Schiff base formation between aldehyde and amino groups of mannose and gelatin, respectively. Prepared microspheres offered suitable physicochemical characteristics for their delivery to AMs. Their average size was about 4 μm and drug entrapment efficiency of 56% was achieved with them. Ex vivo uptake results indicated that in comparison to plain microspheres, m-GMs were selectively uptaken and were found to be associated with phago-lysosomal vesicles of AMs. Pharmacokinetic studies showed the formulation could maintain the therapeutic concentration of INH for prolonged period of time even with a reduced clinical dose. m-GMs were found to be stable in broncheo-alveolar lavage fluid. The study concluded that ligand decorated carriers could be a potential strategy to improve the therapeutic properties of INH.  相似文献   
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164.
Recently, there have been several reports referring to detrimental effects due to radio frequency electromagnetic fields (RF-EMF) exposure. Special attention was given to investigate the effect of mobile phone exposure on the rat brain. Since the integrative mechanism of the entire body lies in the brain, it is suggestive to analyze its biochemical aspects. For this, 35-day old Wistar rats were exposed to a mobile phone for 2?h per day for a duration of 45 days where specific absorption rate (SAR) was 0.9?W/Kg. Animals were divided in two groups: sham exposed (n?=?6) and exposed group (n?=?6). Our observations indicate a significant decrease (P?相似文献   
165.
Criocerine leaf beetles found in Nepal feeding on Dioscorea bulbifera (L.), an invasive weed of Asian origin, were identified as Lilioceris cheni Gressitt and Kimoto based on a synopsis of the Oriental Lilioceris species and review of the Lilioceris impressa species group. All the continental, Oriental species included in the group are diagnosed and illustrated, and a key for their identification is provided. Species status of Lilioceris thibetana Pic, 1916 is resurrected. The following new synonyms are proposed: Lilioceris coomani (Pic, 1928) = Lilioceris egena (Weise, 1922), and Lilioceris subcostata (Pic, 1921a), Lilioceris laticornis (Gressit, 1942), Lilioceris inflaticornis Gressit & Kimoto, 1961, and Lilioceris maai Gressit & Kimoto, 1961 = Lilioceris impressa (Fabricius, 1787). Lectotypes of the following species are designated: Lilioceris coomani Pic, 1928; Lilioceris impressa (Fabricius, 1787); Lilioceris laosensis (Pic, 1916); Lilioceris malabarica (Jacoby, 1904); Lilioceris ruficornis (Pic, 1921b); Lilioceris subcostata (Pic, 1921a); Lilioceris thibetana (Pic, 1916); and Lilioceris unicolor (Hope, 1831).  相似文献   
166.
SUMMARY: Data processing, analysis and visualization (datPAV) is an exploratory tool that allows experimentalist to quickly assess the general characteristics of the data. This platform-independent software is designed as a generic tool to process and visualize data matrices. This tool explores organization of the data, detect errors and support basic statistical analyses. Processed data can be reused whereby different step-by-step data processing/analysis workflows can be created to carry out detailed investigation. The visualization option provides publication-ready graphics. Applications of this tool are demonstrated at the web site for three cases of metabolomics, environmental and hydrodynamic data analysis. AVAILABILITY: datPAV is available free for academic use at http://www.sdwa.nus.edu.sg/datPAV/.  相似文献   
167.
168.
Rhodospirillum rubrum (Esmarch 1887) Molisch 1907 is the type species of the genus Rhodospirillum, which is the type genus of the family Rhodospirillaceae in the class Alphaproteobacteria. The species is of special interest because it is an anoxygenic phototroph that produces extracellular elemental sulfur (instead of oxygen) while harvesting light. It contains one of the most simple photosynthetic systems currently known, lacking light harvesting complex 2. Strain S1(T) can grow on carbon monoxide as sole energy source. With currently over 1,750 PubMed entries, R. rubrum is one of the most intensively studied microbial species, in particular for physiological and genetic studies. Next to R. centenum strain SW, the genome sequence of strain S1(T) is only the second genome of a member of the genus Rhodospirillum to be published, but the first type strain genome from the genus. The 4,352,825 bp long chromosome and 53,732 bp plasmid with a total of 3,850 protein-coding and 83 RNA genes were sequenced as part of the DOE Joint Genome Institute Program DOEM 2002.  相似文献   
169.

Background

Patients with epilepsy often suffer from other important conditions. The existence of such co-morbidities is frequently not recognized and their relationship with epilepsy usually remains unexplained.

Methodology/Principal Findings

We describe three patients with common, sporadic, non-syndromic epilepsies in whom large genomic microdeletions were found during a study of genetic susceptibility to epilepsy. We performed detailed gene-driven clinical investigations in each patient. Disruption of the function of genes in the deleted regions can explain co-morbidities in these patients.

Conclusions/Significance

Co-morbidities in patients with epilepsy can be part of a genomic abnormality even in the absence of (known) congenital malformations or intellectual disabilities. Gene-driven phenotype examination can also reveal clinically significant unsuspected condition.  相似文献   
170.

Background

We have previously shown that ADP-induced TXA2 generation requires signaling from αIIbβ3 integrin in platelets. Here we observed that, unlike ADP, protease-activated receptor (PAR)-mediated TXA2 generation occurs independently of αIIbβ3. PAR agonists, but not ADP, activate G12/13 signaling pathways. Hence, we evaluated the role of these pathways in TXA2 generation.

Principal Findings

Inhibition of ADP-induced thromboxane generation by fibrinogen receptor antagonist SC57101 was rescued by co-stimulation of G12/13 pathways with YFLLRNP. This observation suggested an existence of a common signaling effector downstream of integrins and G12/13 pathways. Hence, we evaluated role of three potential tyrosine kinases; c-Src, Syk and FAK (Focal Adhesion Kinase) that are known to be activated by integrins. c-Src and Syk kinase did not play a role in ADP-induced functional responses in platelets. Selective activation of G12/13 pathways resulted in the activation of FAK, in the absence of integrin signaling. Interestingly, αIIbβ3-mediated FAK activation occurred in a Src family kinase (SFK)-independent manner whereas G12/13 pathway caused FAK activation in a SFK and RhoA-dependent manner. A FAK selective inhibitor TAE-226, blocked TXA2 generation. However, in comparison to WT mice, Pf4-Cre/Fak-Floxed mice did not show any difference in platelet TXA2 generation.

Conclusions

Therefore, we conclude that differential activation of FAK occurs downstream of Integrins and G12/13 pathways. However, the common effector molecule, possibly a tyrosine kinase downstream of integrins and G12/13 pathways contributing to TXA2 generation in platelets remains elusive.  相似文献   
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