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1.
A comparison was made of the relative effectiveness of sponge pessaries impregnated with 40mg flourogestone acetate (FGA) or 60mg medroxyprogesterone acetate (MAP) to induce a synchronized estrus in ewes. Ewes were treated with sponge pessaries for 14 days and 500 IU pregnant mares' serum gonadotropin was injected i.m. at the time of sponge removal. The degree and pattern of mating response of ewes were similar, irrespective of the treatment used, approximately 92% of the ewes being marked by the ram by 72h after sponge removal. No significant differences in fertility or litter size were observed between the treatment groups. Ewes treated with FGA sponges had a fertility of 53% and litter size of 2.3 after mating at the synchronized estrus. The corresponding values for ewes treated with MAP sponges were 57% and 2.1. Use of MAP sponges was associated with a 17.8% sponge loss during treatment compared with 1% sponge loss in ewes treated with FGA sponges. Such losses could compromise the use of MAP sponges by reducing their overall efficacy. 相似文献
2.
Using data for 27 Texas counties from 1978-1987, it is shown that the incidence rates of suicide, homicide, and rape are significantly higher in counties whose drinking water supplies contain little or no lithium than in counties with water lithium levels ranging from 70-170 micrograms/L; the differences remain statistically significant (p less than 0.01) after corrections for population density. The corresponding associations with the incidence rates of robbery, burglary, and theft were statistically significant with p less than 0.05. These results suggest that lithium has moderating effects on suicidal and violent criminal behavior at levels that may be encountered in municipal water supplies. Comparisons of drinking water lithium levels, in the respective Texas counties, with the incidences of arrests for possession of opium, cocaine, and their derivatives (morphine, heroin, and codeine) from 1981-1986 also produced statistically significant inverse associations, whereas no significant or consistent associations were observed with the reported arrest rates for possession of marijuana, driving under the influence of alcohol, and drunkenness. These results suggest that lithium at low dosage levels has a generally beneficial effect on human behavior, which may be associated with the functions of lithium as a nutritionally-essential trace element. Subject to confirmation by controlled experiments with high-risk populations, increasing the human lithium intakes by supplementation, or the lithiation of drinking water is suggested as a possible means of crime, suicide, and drug-dependency reduction at the individual and community level. 相似文献
3.
Niraj Shrestha Pallavi Chaturvedi Xiaoyun Zhu Michael J. Dee Varghese George Christopher Janney Jack O. Egan Bai Liu Mark Foster Lynne Marsala Pamela Wong Celia C. Cubitt Jennifer A. Foltz Jennifer Tran Timothy Schappe Karin Hsiao Gilles M. Leclerc Lijing You Christian Echeverri Catherine Spanoudis Ana Carvalho Leah Kanakaraj Crystal Gilkes Nicole Encalada Lin Kong Meng Wang Byron Fang Zheng Wang Jin-an Jiao Gabriela J. Muniz Emily K. Jeng Nicole Valdivieso Liying Li Richard Deth Melissa M. Berrien-Elliott Todd A. Fehniger Peter R. Rhode Hing C. Wong 《Aging cell》2023,22(5):e13806
4.
Henry Taylor Jane Teas Thomas Richie Charles Southwick Ram Shrestha 《Primates; journal of primatology》1978,19(2):343-351
In 1,506 hours of field observations on free-ranging rhesus monkeys in Kathmandu Valley, Nepal, in 1974 and 1975 18 cases
of favorable social interactions between adult males and infants were observed. Eleven of these were brief encounters of play
or grooming; seven were more extended cases of male care. One of the latter was a complete adoption of a neonatal orphan by
a dominant male. This adoption was possessive and restrictive and it resulted in the death of the infant by starvation within
three days. A similar adoption involving the same male occurred in 1976 and it also resulted in the death of the infant. Most
of the favorable male-infant interactions occurred during the winter and spring when the infants were 6 to 12 months of age.
These favorable social interactions involved eight males in six different troops, out of a total of about 48 males in 12 troops
in our study population of approximately 600 monkeys. These observations are discussed in light of current sociobiological
theories. 相似文献
5.
Histology and annual cyclic changes in the testicular activity of S. plagiostomus have been described. The reproductive cycle has been divided into eight phases. The weight and volume of the testes and GSI show correlation with each other, and increase twice in a year (September and March), indicating the existence of two spawning periods. A distinct dormant period during winter intervenes the spawning peaks. Although the testes contain mature spermatozoa during winter, spermiation remains halted until last week of February. On the return of favourable environmental conditions in March, spermiation begins again and complete depletion takes place. 相似文献
6.
Jaing C Gardner S McLoughlin K Mulakken N Alegria-Hartman M Banda P Williams P Gu P Wagner M Manohar C Slezak T 《PloS one》2008,3(5):e2163
Emerging known and unknown pathogens create profound threats to public health. Platforms for rapid detection and characterization of microbial agents are critically needed to prevent and respond to disease outbreaks. Available detection technologies cannot provide broad functional information about known or novel organisms. As a step toward developing such a system, we have produced and tested a series of high-density functional gene arrays to detect elements of virulence and antibiotic resistance mechanisms. Our first generation array targets genes from Escherichia coli strains K12 and CFT073, Enterococcus faecalis and Staphylococcus aureus. We determined optimal probe design parameters for gene family detection and discrimination. When tested with organisms at varying phylogenetic distances from the four target strains, the array detected orthologs for the majority of targeted gene families present in bacteria belonging to the same taxonomic family. In combination with whole-genome amplification, the array detects femtogram concentrations of purified DNA, either spiked in to an aerosol sample background, or in combinations from one or more of the four target organisms. This is the first report of a high density NimbleGen microarray system targeting microbial antibiotic resistance and virulence mechanisms. By targeting virulence gene families as well as genes unique to specific biothreat agents, these arrays will provide important data about the pathogenic potential and drug resistance profiles of unknown organisms in environmental samples. 相似文献
7.
Wen JJ Zago MP Nuñez S Gupta S Burgos FN Garg NJ 《Molecular & cellular proteomics : MCP》2012,11(8):435-452
Chagas disease is initiated upon infection by Trypanosoma cruzi. Among the health consequences is a decline in heart function, and the pathophysiological mechanisms underlying this manifestation are not well understood. To explore the possible mechanisms, we employed IgY LC10 affinity chromatography in conjunction with ProteomeLab PF2D and two-dimensional gel electrophoresis to resolve the proteome signature of high and low abundance serum proteins in chagasic patients. MALDI-TOF MS/MS analysis yielded 80 and 14 differentially expressed proteins associated with cardiomyopathy of chagasic and other etiologies, respectively. The extent of oxidative stress-induced carbonyl modifications of the differentially expressed proteins (n = 26) was increased and coupled with a depression of antioxidant proteins. Functional annotation of the top networks developed by ingenuity pathway analysis of proteome database identified dysregulation of inflammation/acute phase response signaling and lipid metabolism relevant to production of prostaglandins and arachidonic acid in chagasic patients. Overlay of the major networks identified prothrombin and plasminogen at a nodal position with connectivity to proteome signature indicative of heart disease (i.e., thrombosis, angiogenesis, vasodilatation of blood vessels or the aorta, and increased permeability of blood vessel and endothelial tubes), and inflammatory responses (e.g., platelet aggregation, complement activation, and phagocyte activation and migration). The detection of cardiac proteins (myosin light chain 2 and myosin heavy chain 11) and increased levels of vinculin and plasminogen provided a comprehensive set of biomarkers of cardiac muscle injury and development of clinical Chagas disease in human patients. These results provide an impetus for biomarker validation in large cohorts of clinically characterized chagasic patients. 相似文献
8.
9.
Robo4 maintains vessel integrity and inhibits angiogenesis by interacting with UNC5B 总被引:1,自引:0,他引:1
Koch AW Mathivet T Larrivée B Tong RK Kowalski J Pibouin-Fragner L Bouvrée K Stawicki S Nicholes K Rathore N Scales SJ Luis E del Toro R Freitas C Bréant C Michaud A Corvol P Thomas JL Wu Y Peale F Watts RJ Tessier-Lavigne M Bagri A Eichmann A 《Developmental cell》2011,20(1):33-46
Robo4 is an endothelial cell-specific member of the Roundabout axon guidance receptor family. To identify Robo4 binding partners, we performed a protein-protein interaction screen with the Robo4 extracellular domain. We find that Robo4 specifically binds to UNC5B, a vascular Netrin receptor, revealing unexpected interactions between two endothelial guidance receptors. We show that Robo4 maintains vessel integrity by activating UNC5B, which inhibits signaling downstream of vascular endothelial growth factor (VEGF). Function-blocking monoclonal antibodies against Robo4 and UNC5B increase angiogenesis and disrupt vessel integrity. Soluble Robo4 protein inhibits VEGF-induced vessel permeability and rescues barrier defects in Robo4(-/-) mice, but not in mice treated with anti-UNC5B. Thus, Robo4-UNC5B signaling maintains vascular integrity by counteracting VEGF signaling in endothelial cells, identifying a novel function of guidance receptor interactions in the vasculature. 相似文献
10.
Reelin is an extracellular matrix molecule that is involved in the normal development of the cerebellar lamination, Bergmann glial fibres alignment, Purkinje cell monolayer arrangement and granule cell migration. In this study, we have examined the effects of maternal exposure of deltamethrin (DLT), a type II pyrethroid insecticide, on the structural and functional development of rat cerebellum during postnatal life. DLT (0.75 mg/kg body weight, intraperitoneally dissolved in dimethylsulphoxide) was administered in timed pregnant rats during two different gestational time periods, i.e. gestational days of 7–10 and 11–14, respectively. In DLT exposed rats, a significant overexpression of reelin was observed in the cells of the external granule cell layer (EGL) and internal granule cell layer along with an ectopic expression of reelin in the EGL as well as in the migrating granule cells just below the EGL, revealing an arrest of granule cell migration in this zone. Mis-orientation and hypertrophy of the Bergmann glial fibres further hampered the journey of the granule cells to their final destination. Possibly reelin overexpression also caused misalignment of the Purkinje cells and inhibited the neurite growth leading to a significant decrease in the spine density, main dendritic length and width of the dendritic arbour. Thus, it is proposed that the DLT exerts its neurotoxic effects possibly via the intracellular accumulation and low release of reelin leading to an impaired granule cell and Purkinje cell migration, inhibition of neurite outgrowth and reduced spine density. Such impaired cerebellar development leads to motor coordination deficits. 相似文献