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101.
Rhus coriaria var. zebaria from Duhok/Aqrae, Kurdistan, Iraq is described as a variety new to science. Field expeditions started in spring 2011, continued during 2012 and 2013 with the aim of collecting sumac specimens from different physiographic regions of Kurdistan, Iraq. A total of ten plants for each variety were sampled. An equal number of tagged herbarium specimens were prepared. The holotype was designated and deposited together with other herbarium specimens in the herbarium of the Faculty of Agriculture and Forestry, Univ. of Duhok. Morphological characters of the leaf, inflorescence, flowers, infructescence, and fruit were studied. The pH value of the pericarp in addition to the hilum length was measured. Results were compared with Rhus coriaria L. var. coriaria. The most distinctive feature of the new variety is the dull whitish brown color of the drupe pericarp of var. zebaria as compared to the reddish brown color of the drupe pericarp of var. coriaria. The whitish color of the drupes of var. zebaria, in combination with their larger size, represents diagnostic characters for distinguishing this variety. In contrast, most leaf characters are of little or no taxonomic value in this species. Only shape, apex and marginal teeths of the leaflets show minor differences for separating the two varieties. Female and male inflorescences and flowers characters show no significant differences. Both hilum length and pH value characters may be useful for taxonomic application if mean values are taken in consideration.  相似文献   
102.
Rosularia globulariifolia (Fenzl) A. Berger and R. pallidiflora (Holmboe) Meikle were originally described as species in Umbilicus DC. in 1842 and 1914, respectively. In the present study, morphological and palynological features were examined in detail to determine the status of these taxa. The general characteristics, seed structure and micromorphology, pollen measurements and pollen characteristics were established. Morphologically, the two taxa cannot easily be distinguished. Pollen grains of both species are tricolporate, subspheroidal and eutectate, ornamentation is psilate and exine structures are similar. Based on morphological and palynological similarities, and the fact that both taxa are found in the same habitats, we propose that R. pallidiflora should be reduced to the rank of variety as Rosularia globulariifolia (Fenzl) A. Berger var. pallidiflora (Meikle) Minareci & K. Yildiz comb. et stat. nov.  相似文献   
103.
The enzyme Necator americanus glutathione S-transferase 1 (Na-GST-1) belongs to a unique Nu class of GSTs and is a lead candidate antigen in a bivalent human hookworm vaccine. Here we describe the expression of Na-GST-1 in the yeast Pichia pastoris at the 20 L manufacturing scale and its purification process performed by three chromatographic steps, comprised of a Q Sepharose XL anion exchange column, followed by a Butyl Sepharose HP hydrophobic affinity column and a Superdex 75 size-exclusion column. Approximately 1.5 g of recombinant protein was recovered at an overall process yield of 51%, with a purity grade of 98% and the absence of detectable host cell protein. By mass spectrometry the recombinant protein exhibits a mass of 23,676Da, which closely matches the predicted molecular mass of the protein. The expression and purification methods described here are suitable for further scale-up product development and for its use to design formulation processes suitable to generate a vaccine for clinical testing.  相似文献   
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Bacterial pili are important virulence factors involved in host cell attachment and/or biofilm formation, key steps in establishing and maintaining successful infection. Here we studied Salmonella atypical fimbriae (or Saf pili), formed by the conserved chaperone/usher pathway. In contrast to the well-established quaternary structure of typical/FGS-chaperone assembled, rod-shaped, chaperone/usher pili, little is known about the supramolecular organisation in atypical/FGL-chaperone assembled fimbriae. In our study, we have used negative stain electron microscopy and single-particle image analysis to determine the three-dimensional structure of the Salmonella typhimurium Saf pilus. Our results show atypical/FGL-chaperone assembled fimbriae are composed of highly flexible linear multi-subunit fibres that are formed by globular subunits connected to each other by short links giving a “beads on a string”-like appearance. Quantitative fitting of the atomic structure of the SafA pilus subunit into the electron density maps, in combination with linker modelling and energy minimisation, has enabled analysis of subunit arrangement and intersubunit interactions in the Saf pilus. Short intersubunit linker regions provide the molecular basis for flexibility of the Saf pilus by acting as molecular hinges allowing a large range of movement between consecutive subunits in the fibre.  相似文献   
106.
Young rats treated daily with intraperitoneal 4-vinylcyclohexene diepoxide (VCD) undergo selective destruction of primordial follicles, resulting in gradual ovarian failure resembling the menopausal transition in women. To determine whether VCD has similar effects on ovaries of older rats, adult and peripubertal Sprague–Dawley rats were injected intraperitoneally daily for 30 d with vehicle or VCD at 40 or 80 mg/kg. Body weight, food intake, complete blood counts, and markers of liver injury and renal function were measured during VCD treatment. Complete gross necropsy and microscopic observations were performed on day 31, and ovarian follicles were counted. At 80 mg/kg, VCD destroyed primordial and primary follicles to a similar extent in both adult and peripubertal animals, although adult rats likely started with fewer follicles and therefore approached follicle depletion. Treatment with VCD did not affect body weight, but food intake was reduced in both adult and peripubertal rats treated with 80 mg/kg VCD. Adult rats treated with 80 mg/kg VCD had neutrophilia and increased BUN and creatinine; in addition, 4 of these rats were euthanized on days 25 or 26 due to peritonitis. VCD treatment did not increase alanine aminotransferase levels, a marker of liver injury, although the 80-mg/kg dose increased liver weights. In conclusion, VCD effectively destroys small preantral follicles in adult Sprague–Dawley rats, making them a suitable model of the menopausal transition of women. However, because adult rats were more sensitive to the irritant properties of VCD, the use of a lower dose should be considered.Abbreviations: VCD, 4-vinylcyclohexene diepoxideStudies attempting to model the human menopause have relied heavily on using animals from which the ovaries have been removed surgically (ovariectomy). This approach has important limitations because women who enter natural menopause still have ovaries, which continue to produce hormones. Therefore, studies using ovariectomized animals cannot model the hormonal changes associated with the menopausal transition and postmenopausal period. However, rodent models of the menopausal transition and menopause that more closely mimic those of women have recently been developed.32,33,36 Mice or rats treated with daily intraperitoneal injections of the chemical 4-vinylcyclohexene diepoxide (VCD) undergo selective destruction of primordial and primary follicles.25 This treatment results in a gradual onset of ovarian failure because remaining larger follicles continue to develop and then ovulate or undergo atresia until they are depleted.36 These studies also demonstrate that the length of time to ovarian failure is dependent on VCD dose and duration of treatment.33,37 Moreover, in VCD-treated mice, the resulting follicle-depleted, stroma-intact ovary retains the ability to produce androgens.36 Therefore, taken together, these characteristics indicate that VCD-treated animals could be used to model the menopausal transition of women and enable research on diseases affecting women postmenopausally.The ability of VCD to destroy preantral follicles in rats by repeated dosing has been well documented.16,23,24,37 However, to our knowledge, all of the VCD studies using rats that have been published to date have used peripubertal or young (28 to 58 d) Fisher 344 rats. Although younger animals have been useful in separating the effect of age from the effect of hormonal changes associated with VCD-induced ovarian failure,22,27,32,37 the use of older rodents may provide a more appropriate model for studying the combined effects of aging and hormonal aspects of menopause (for example, osteoporosis, cognitive decline, ovarian cancer).Both young and adult Sprague–Dawley rats have been used extensively to model menopausal effects on osteoporosis,3,4,13,38,49 brain and cognitive functioning,2,14,15,29,34 lipids and cardiovascular health,30,35,53 bladder health and incontinence,6,21,31 and breast cancer.8,18,43,44 These studies used ovariectomized Sprague–Dawley rats ranging in age from 42 to 210 d. The use of this chemically induced model of menopause would be enhanced by determining whether VCD affects Sprague–Dawley rats differently and whether VCD has deleterious effects on nonovarian tissues. Furthermore, although more than a dozen publications have reported that repeated VCD dosing does not adversely affect young rodents,19,32,33,36,56 similar data have not been reported for adult Sprague–Dawley rats. The purpose of this study was to determine whether VCD affects the ovaries of peripubertal (28 d) and adult Sprague–Dawley rats differently.  相似文献   
107.
The symbiotic biological N2fixation by Acacia senegal was estimated using the 15N natural abundance (δ 15N) procedure on eight provenances collected from different environments and soil types grown in a clay soil in the Blue Nile region, Sudan. Balanites aegyptiaca (a non-legume) was used as a non-N2-fixing reference plant to allow 15N-based estimates of the proportion of the Acacia N derived from atmospheric N2 (Ndfa) to be calculated. Results show variation in leaf δ 15N between A. senegal and the reference plant and among years. The relative δ 15N values (‰) were higher in B. aegyptiaca than in the N2-fixing acacia provenances. Provenances originally collected from clay soils fixed little N in the first year, but the amount fixed increased as the trees aged. All provenances showed a decrease in δ 15N with age. The Ndfa varied between 24% (Mazmoom provenance) and 61% (Rahad provenance) 4 years after planting. There was no significant difference in δ 15N between provenance groups based on soil type or rainfall at original growing site. The amount of Ndfa increased significantly with age in all provenances. The above-ground contribution of fixed N to foliage growth in a 4-year-old A. senegal was highest in the Rahad sand–soil provenance (46.7 kg N ha−1) and lowest in the Mazmoom clay-soil provenance (28.7 kg N ha−1). Our study represents the first use of the δ 15N method for estimating the N input by A. senegal to the clay plain soils of the gum belt in the Sudan.  相似文献   
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Pituitary adenoma in a rabbitA 44-mo-old, female, nulliparous New Zealand White Rabbit (Oryctolagus cuniculus) presented with bilaterally diffusely enlarged mammary glands with enlarged, discolored teats that exuded brown, mucoid discharge. The complete blood count and serum chemistry panels were within normal limits, bacteria were not isolated from a culture of the discharge, and the clinical signs did not resolve with antibiotic treatment. Computed tomography and serum prolactin levels supported the diagnosis of mammary gland dysplasia, possibly due to a prolactin-secreting pituitary adenoma. Histologic evaluation confirmed the presence of a pituitary adenoma, mammary hyperplasia, dysplasia, and cystic mammary adenocarcinoma. Immunohistochemical staining confirmed the presence of abundant prolactin secreting cells in the pituitary adenoma. This is the second report of hyperprolactinemia with mammary dysplasia in rabbits, and the first report of cystic mammary adenocarcinoma associated with a prolactin-secreting pituitary adenoma in a rabbit.  相似文献   
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