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91.
92.
Application of ultrasound for pregnancy diagnosis has been tested and evaluated in 15 Iranian camels (Camelus dromedarius), all of which ultimately calved. Transabdominal examinations were unsuccessful, while intrapelvic application resulted in the reception of sounds characteristic for foetal life, similar to those found in other domestic animals. Signals of foetal heart, pulse of umbilical vessels and uterine artery as well as foetal movement could be recognized as distinct sounds and have been recorded for further studies. An attempt was made to verify the findings of the ultrasonic diagnosis through rectal palpation. The ultrasonic technique resulted in 12 correct and three incorrect diagnoses. 相似文献
93.
Ribosomal protein S14 genes (RPS14) in eukaryotic species from protozoa to
primates exhibit dramatically different intron-exon structures yet share
homologous polypeptide-coding sequences. To recognize common features of
RPS14 gene architectures in closely related mammalian species and to
evaluate similarities in their noncoding DNA sequences, we isolated the
intron-containing S14 locus from Chinese hamster ovary (CHO) cell DNA by
using a PCR strategy and compared it with human RPS14. We found that rodent
and primate S14 genes are composed of identical protein-coding exons
interrupted by introns at four conserved DNA sites. However, the structures
of corresponding CHO and human RPS14 introns differ significantly.
Nonetheless, individual intron splice donor, splice acceptor, and upstream
flanking motifs have been conserved within mammalian S14 homologues as well
as within RPS14 gene fragments PCR amplified from other vertebrate genera
(birds and bony fish). Our data indicate that noncoding, intronic DNA
sequences within highly conserved, single-copy ribosomal protein genes are
useful molecular landmarks for phylogenetic analysis of closely related
vertebrate species.
相似文献
94.
Christopher A. Willoughby Scott C. Berk Keith G. Rosauer Silvia Degrado Kevin T. Chapman Sandra L. Gould Martin S. Springer Lorraine Malkowitz William A. Schleif Daria Hazuda Michael Miller Joseph Kessler Renee Danzeisen Karen Holmes Janet Lineberger Anthony Carella Gwen Carver Emilio A. Emini 《Bioorganic & medicinal chemistry letters》2001,11(24):1299-3141
Herein we report the preparation of a combinatorial library of compounds with potent CCR5 binding affinity. The library design was aided by SAR generated in a traditional medicinal chemistry effort. Compounds with novel combinations of subunits were discovered that have high binding affinity for the CCR5 receptor. A potent CCR5 antagonist from the library, compound 11 was found to have moderate anti-HIV-1 activity. 相似文献
95.
George?M?WarimweEmail author Gema?Lorenzo Elena?Lopez-Gil Arturo?Reyes-Sandoval Matthew?G?Cottingham Alexandra?J?Spencer Katharine?A?Collins Matthew?DJ?Dicks Anita?Milicic Amar?Lall Julie?Furze Alison?V?Turner Adrian?VS?Hill Alejandro?Brun Sarah?C?Gilbert 《Virology journal》2013,10(1):349
Background
Rift Valley Fever (RVF) is a viral zoonosis that historically affects livestock production and human health in sub-Saharan Africa, though epizootics have also occurred in the Arabian Peninsula. Whilst an effective live-attenuated vaccine is available for livestock, there is currently no licensed human RVF vaccine. Replication-deficient chimpanzee adenovirus (ChAd) vectors are an ideal platform for development of a human RVF vaccine, given the low prevalence of neutralizing antibodies against them in the human population, and their excellent safety and immunogenicity profile in human clinical trials of vaccines against a wide range of pathogens.Methods
Here, in BALB/c mice, we evaluated the immunogenicity and efficacy of a replication-deficient chimpanzee adenovirus vector, ChAdOx1, encoding the RVF virus envelope glycoproteins, Gn and Gc, which are targets of virus neutralizing antibodies. The ChAdOx1-GnGc vaccine was assessed in comparison to a replication-deficient human adenovirus type 5 vector encoding Gn and Gc (HAdV5-GnGc), a strategy previously shown to confer protective immunity against RVF in mice.Results
A single immunization with either of the vaccines conferred protection against RVF virus challenge eight weeks post-immunization. Both vaccines elicited RVF virus neutralizing antibody and a robust CD8+ T cell response.Conclusions
Together the results support further development of RVF vaccines based on replication-deficient adenovirus vectors, with ChAdOx1-GnGc being a potential candidate for use in future human clinical trials.96.
97.
98.
Lynch CL Gentry AL Hale JJ Mills SG MacCoss M Malkowitz L Springer MS Gould SL DeMartino JA Siciliano SJ Cascieri MA Doss G Carella A Carver G Holmes K Schleif WA Danzeisen R Hazuda D Kessler J Lineberger J Miller M Emini EA 《Bioorganic & medicinal chemistry letters》2002,12(4):677-679
A series of CCR5 antagonists containing bicyclic isoxazolidines was generated through a nitrone mediated cycloaddition with olefins bearing the preferred pharmacophores previously described. Potent antagonists (3 and 16) were generated with enhanced affinity for the CCR5 receptor while maintaining antiviral activity against HIV. 相似文献
99.
This article selectively reviews research concerning nicotine's effects on cognition, including the neurobiological mechanism for these effects, task and experimental features that may be important for elucidating these effects, and why these effects may have amplified motivational significance among smokers with cognitive deficit. Nicotine has effects on various cognitive processes, though most studies in humans have focused on the amelioration of cognitive deficits experienced during drug withdrawal. The direct cognitive-enhancing effect of nicotine remains a controversial topic. The relationship between attentional and non-attentional cognitive effects of nicotine is discussed in the context of cognitive self-medication. Further research should include theory-driven examination of cognitive effects of nicotine, and develop targeted smoking cessation programs based on an improved understanding of the role of cognitive self-medication in high-risk individuals. 相似文献
100.
Shankaran K Donnelly KL Shah SK Caldwell CG Chen P Finke PE Oates B MacCoss M Mills SG DeMartino JA Gould SL Malkowitz L Siciliano SJ Springer MS Kwei G Carella A Carver G Danzeisen R Hazuda D Holmes K Kessler J Lineberger J Miller MD Emini EA Schleif WA 《Bioorganic & medicinal chemistry letters》2004,14(13):3589-3593
Cellular proliferation of HIV-1 requires the cooperative assistance of both the CCR5 and CD4 receptors. Our medicinal chemistry efforts in this area have resulted in the identification of N-alkyl piperidine sulfones as CCR5 antagonists. These compounds display potent binding and show antiviral properties in HIV-1 spread cell-based assays. 相似文献