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31.
Sialomucin Complex (Muc4) Expression in Porcine Endometrium During the Oestrous Cycle and Early Pregnancy 总被引:1,自引:0,他引:1
The non‐invasive type of implantation in the pig is characterized by the maintenance of a thick glycocalyx coating on the uterine epithelial surface microvilli. Present study investigated the alteration in the sialomucin complex (Muc4) expression during the oestrous cycle and early pregnancy in the pig. Endometrial tissue samples were immunostained with the primary antibody to the Muc4 transmembrane subunit ASGP‐2. Muc4 immunostaining increased in the surface and glandular epithelia between days 5 and 10 of oestrous cycle. Immunostaining continued to increase on day 12 with the greatest intensity of uterine Muc4 immunostaining detected on day 15 of the oestrous cycle and early pregnancy. Endometrial Muc4 expression in cyclic gilts decreased dramatically during early proestrous but continued to remain abundant in the surface and glandular epithelium of pregnant gilts during the period of conceptus attachment to the uterine surface. 相似文献
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Peridotite xenoliths from the Cascade arc in the United States and in the Japan arc have neodymium and osmium isotopic compositions that are consistent with addition of 5 to 15 percent of subducted material to the present-day depleted mantle. These observations suggest that osmium can be partitioned into oxidized and chlorine-rich slab-derived fluids or melts. These results place new constraints on the behavior of osmium (and possibly other platinum group elements) during subduction of oceanic crust by showing that osmium can be transported into the mantle wedge. 相似文献
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Abstract CASE HISTORY: In 2008, a 3-year-old female Labrador Retriever was presented for routine breeding soundness evaluation. CLINICAL FINDINGS: Vaginal endoscopy revealed an 8-cm long and 1-cm thick vaginal septum. Surgical resection of the septum was performed under general anaesthesia using a bipolar high-frequency resectoscope. Three months later the bitch was naturally mated and subsequently delivered five male and two female puppies without complications. Both female puppies were examined at the age of 12 and 15 months and showed a vaginal septum with a diameter of 0.3 and 0.5 cm, respectively. DIAGNOSIS: Vaginal septa in three related bitches. CLINICAL RELEVANCE: This is the first report describing the use of a bipolar high-frequency resectoscope for vaginal surgery in dogs. The septum could be resected quickly, with preservation of surrounding structures. Furthermore, it is the first report collecting information about familial presentation of vaginal septa in female dogs. Based on this case, we suggest that consideration should be given to the possible risk of inheritance of vaginal septa before considering surgical resection and breeding of female dogs. 相似文献
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MA Beswick N Choi CN Harmer AD Hopkins M McPartlin DS Wright 《Science (New York, N.Y.)》1998,281(5382):1500-1501
Thermolysis of the heterobimetallic phosphinidene complex [Sb(PCy)3]2- Li6.6HNMe2 (Cy = C6H11) at 303 to 313 kelvin gives Zintl compounds containing (Sb7)3- anions. The complex thus constitutes a stable molecular single-source precursor to Zintl compounds and provides a potential low-temperature route to photoactive alkali metal antimonates. The new chemical reaction involved, which is driven thermodynamically by the formation of P-P bonds, has implications in the low-temperature synthesis of other technologically important materials (such as gallium arsenide). 相似文献
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The vegetation of the Wet Tropics bioregion of Far North Queensland is a complex system whose components (mainly tropical
rainforests and fire-prone forests and woodlands) have mostly been studied independently from each other. We suggest that
many characteristics of the vegetation are consistent with those of a complex, dynamic, spatially heterogeneous system which
exhibits alternative stable states. We propose these states are driven and maintained by the interaction of vegetation-specific
positive feedback loops with the regions’ environmental parameters (such as topography, steep humidity gradients and seasonality)
and result in the rainforest/fire-prone vegetation mosaic that characterises the area. Given the regions’ magnitude, biodiversity
and complexity, we propose the Wet Tropics as an important new example and a good testing ground for alternative stable state
and resilience theories in large heterogeneous natural systems. At the same time, thinking in terms of alternative stable
states and resilience creates a new context for understanding the regions’ biological dynamics. 相似文献
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M. D. Moles T. A. Johnston B. W. Robinson A. M. Bernard C. C. Wilson M. D. Wiegand W. C. Leggett 《Ecology of Freshwater Fish》2011,20(1):52-66
Moles MD, Johnston TA, Robinson BW, Bernard AM, Wilson CC, Wiegand MD, Leggett WC. Reproductive divergence between growth forms of Lake Winnipeg walleye (Sander vitreus). Ecology of Freshwater Fish 2011: 20: 52–66. © 2010 John Wiley & Sons A/S Abstract – Growth polymorphisms occur in many fish species, particularly in northern temperate freshwater lakes. The only known growth polymorphism in walleye (Sander vitreus) is in Lake Winnipeg, Canada, where slow‐growing (dwarf) and fast‐growing (normal) morphotypes co‐exist. We examined differences in reproductive traits between forms to determine whether divergence in growth rates was accompanied by divergence in reproductive strategies and also assessed the genetic composition of both forms using mitochondrial and microsatellite DNA to determine their origin and potential reproductive isolation. Both sexes of the dwarf form produced relatively larger gonads than the normal form. Female dwarfs also had a lower liver lipid concentration, a higher ovary lipid concentration, and produced relatively larger eggs compared to the normal form. There was also some indication that dwarf and normal females differed in the fatty acid profiles of their egg lipids. Population genetic analysis based on partial sequencing of the mitochondrial control region and genotyping nine microsatellite loci indicated a single interbreeding population and sympatric origin for both morphotypes. The dwarf form appears to make a relatively larger reproductive investment at a given body size, and the differences between the two forms may result from plastic developmental responses to subtle differences in niche use. 相似文献