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81.
Described as a new species is Oreoxis trotteri Welsh & Goodrich from Utah. 相似文献
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Stanley L. Welsh 《西北部美国博物学家》2011,48(1)
The Utah botanical contributions of Charles Christopher Parry are discussed. Especial emphasis is on his trips to Utah in 1874 and 1875. Plants taken during those years, which were subsequently listed as type-specimens, are listed. Insight is gained into this window in Utah botanical history through his letters to Dr. George Engelmann and limited correspondence from Engelmann and Joseph Ellis Johnson. 相似文献
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Stanley L. Welsh 《西北部美国博物学家》2011,35(4)
Cymopterus higginsii and Penstemon atwoodii are named and described from materials collected in the Kaiparowits Plateau vicinity of eastern Kane County, Utah. Habitat, distribution, and probable affinities are outlined. 相似文献
86.
Asclepias sanjuanensis Heil, Porter, & Welsh, a new species from the pinyon-juniper woodlands of the San Juan River Valley, San Juan County, New Mexico, is described and illustratred. The species appears to be local and rare. Similar to A. ruthiae Maguire, it is distinguished by the greater number of flowers per inflorescence, the larger number of stems, and the pubescence characters. 相似文献
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Assessing Accuracy and Precision of a Medical Lab Machine by Means of Cluster Analysis 总被引:1,自引:0,他引:1
Stanley L. Sclove 《Journal of Classification》2002,19(2):197-214
89.
Colony stimulating factor-1 (CSF-1) is a glycoprotein growth factor required for the proliferation and differentiation of mononuclear phagocytic cells (reviewed in ref. 1). A 10,000-fold elevation of mouse uterine CSF-1 during pregnancy, suggested by studies of the bone marrow colony stimulating activity of uterine extracts, was recently demonstrated by radioimmunoassay (RIA). This increase and the observations that placenta and choriocarcinoma cell lines express c-fms messenger RNA and the c-fms proto oncogene product (CSF-1 receptor) respectively, suggest an additional role for CSF-1 in pregnancy. We now show that uterine CSF-1 concentration is regulated by the synergistic action of female sex steroids, oestradiol-17 beta (E2) and progesterone (P) and that the elevation in CSF-1 concentration can be attributed to the preferential expression of an alternatively spliced CSF-1 mRNA by uterine glandular epithelial cells. These findings indicate that CSF-1, under hormonal influence, plays a role in placental development and function and that steroid hormones may regulate developmental processes via their effects on the expression of tissue-specific growth factors. 相似文献
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