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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   
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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   
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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   
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A key challenge in ecology is to understand the relationships between organismal traits and ecosystem processes. Here, with a novel dataset of leaf length and width for 10 480 woody dicots in China and 2374 in North America, we show that the variation in community mean leaf size is highly correlated with the variation in climate and ecosystem primary productivity, independent of plant life form. These relationships likely reflect how natural selection modifies leaf size across varying climates in conjunction with how climate influences canopy total leaf area. We find that the leaf size?primary productivity functions based on the Chinese dataset can predict productivity in North America and vice‐versa. In addition to advancing understanding of the relationship between a climate‐driven trait and ecosystem functioning, our findings suggest that leaf size can also be a promising tool in palaeoecology for scaling from fossil leaves to palaeo‐primary productivity of woody ecosystems.  相似文献   
8.
Damage to proximal tubules due to exposure to toxicants can lead to conditions such as acute kidney injury (AKI), chronic kidney disease (CKD) and ultimately end-stage renal failure (ESRF). Studies have shown that kidney proximal epithelial cells can regenerate particularly after acute injury. In the previous study, we utilized an immortalized in vitro model of human renal proximal tubule epithelial cells, RPTEC/TERT1, to isolate HRTPT cell line that co-expresses stem cell markers CD133 and CD24, and HREC24T cell line that expresses only CD24. HRTPT cells showed most of the key characteristics of stem/progenitor cells; however, HREC24T cells did not show any of these characteristics. The goal of this study was to further characterize and understand the global gene expression differences, upregulated pathways and gene interaction using scRNA-seq in HRTPT cells. Affymetrix microarray analysis identified common gene sets and pathways specific to HRTPT and HREC24T cells analysed using DAVID, Reactome and Ingenuity software. Gene sets of HRTPT cells, in comparison with publicly available data set for CD133+ infant kidney, urine-derived renal progenitor cells and human kidney-derived epithelial proximal tubule cells showed substantial similarity in organization and interactions of the apical membrane. Single-cell analysis of HRTPT cells identified unique gene clusters associated with CD133 and the 92 common gene sets from three data sets. In conclusion, the gene expression analysis identified a unique gene set for HRTPT cells and narrowed the co-expressed gene set compared with other human renal–derived cell lines expressing CD133, which may provide deeper understanding in their role as progenitor/stem cells that participate in renal repair.  相似文献   
9.
Supernumerary mini-chromosomes–a unique type of genomic structural variation–have been implicated in the emergence of virulence traits in plant pathogenic fungi. However, the mechanisms that facilitate the emergence and maintenance of mini-chromosomes across fungi remain poorly understood. In the blast fungus Magnaporthe oryzae (Syn. Pyricularia oryzae), mini-chromosomes have been first described in the early 1990s but, until very recently, have been overlooked in genomic studies. Here we investigated structural variation in four isolates of the blast fungus M. oryzae from different grass hosts and analyzed the sequences of mini-chromosomes in the rice, foxtail millet and goosegrass isolates. The mini-chromosomes of these isolates turned out to be highly diverse with distinct sequence composition. They are enriched in repetitive elements and have lower gene density than core-chromosomes. We identified several virulence-related genes in the mini-chromosome of the rice isolate, including the virulence-related polyketide synthase Ace1 and two variants of the effector gene AVR-Pik. Macrosynteny analyses around these loci revealed structural rearrangements, including inter-chromosomal translocations between core- and mini-chromosomes. Our findings provide evidence that mini-chromosomes emerge from structural rearrangements and segmental duplication of core-chromosomes and might contribute to adaptive evolution of the blast fungus.  相似文献   
10.
Previous studies have demonstrated that type I interferon (IFN-I) restricts West Nile virus (WNV) replication and pathogenesis in peripheral and central nervous system (CNS) tissues. However, the in vivo role of specific antiviral genes that are induced by IFN-I against WNV infection remains less well characterized. Here, using Ifit2−/− mice, we defined the antiviral function of the interferon-stimulated gene (ISG) Ifit2 in limiting infection and disease in vivo by a virulent North American strain of WNV. Compared to congenic wild-type controls, Ifit2−/− mice showed enhanced WNV infection in a tissue-restricted manner, with preferential replication in the CNS of animals lacking Ifit2. Virological analysis of cultured macrophages, dendritic cells, fibroblasts, cerebellar granule cell neurons, and cortical neurons revealed cell type-specific antiviral functions of Ifit2 against WNV. In comparison, small effects of Ifit2 were observed on the induction or magnitude of innate or adaptive immune responses. Our results suggest that Ifit2 restricts WNV infection and pathogenesis in different tissues in a cell type-specific manner.  相似文献   
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