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11.
Cycling virgin female rats were treated with clomiphene citrate (CC) during dioestrus of the reproductive cycle. Animals were sacrificed 2 days after the initial injection and their vaginal tissue was examined by scanning electron microscopy. Animals treated with one dose of CC had an epithelium consistent with a prolonged dioestrus. Treatment with CC for 2 days induced changes in the epithelium that had no resemblance to any normal hormonally controlled event in the vagina. It was found that CC had effects consistent with progesterone alone as well as effects unique to this superovulatory drug. 相似文献
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Stephen M. Techtmann Julian L. Fortney Kati A. Ayers Dominique C. Joyner Thomas D. Linley Susan M. Pfiffner Terry C. Hazen 《PloS one》2015,10(3)
The waters of the Eastern Mediterranean are characterized by unique physical and chemical properties within separate water masses occupying different depths. Distinct water masses are present throughout the oceans, which drive thermohaline circulation. These water masses may contain specific microbial assemblages. The goal of this study was to examine the effect of physical and geological phenomena on the microbial community of the Eastern Mediterranean water column. Chemical measurements were combined with phospholipid fatty acid (PLFA) analysis and high-throughput 16S rRNA sequencing to characterize the microbial community in the water column at five sites. We demonstrate that the chemistry and microbial community of the water column were stratified into three distinct water masses. The salinity and nutrient concentrations vary between these water masses. Nutrient concentrations increased with depth, and salinity was highest in the intermediate water mass. Our PLFA analysis indicated different lipid classes were abundant in each water mass, suggesting that distinct groups of microbes inhabit these water masses. 16S rRNA gene sequencing confirmed the presence of distinct microbial communities in each water mass. Taxa involved in autotrophic nitrogen cycling were enriched in the intermediate water mass suggesting that microbes in this water mass may be important to the nitrogen cycle of the Eastern Mediterranean. The Eastern Mediterranean also contains numerous active hydrocarbon seeps. We sampled above the North Alex Mud Volcano, in order to test the effect of these geological features on the microbial community in the adjacent water column. The community in the waters overlaying the mud volcano was distinct from other communities collected at similar depths and was enriched in known hydrocarbon degrading taxa. Our results demonstrate that physical phenomena such stratification as well as geological phenomena such as mud volcanoes strongly affect microbial community structure in the Eastern Mediterranean water column. 相似文献
16.
Irene Jao Vicki Marsh Primus Che Chi Melissa Kapulu Mainga Hamaluba Sassy Molyneux Philip Bejon Dorcas Kamuya 《Bioethics》2020,34(8):819-832
Controlled human malaria infection (CHMI) studies involve the deliberate infection of healthy volunteers with malaria parasites under controlled conditions to study immune responses and/or test drug or vaccine efficacy. An empirical ethics study was embedded in a CHMI study at a Kenyan research programme to explore stakeholders’ perceptions and experiences of deliberate infection and moral implications of these. Data for this qualitative study were collected through focus group discussions, in-depth interviews and non-participant observation. Sixty-nine participants were involved, including CHMI study volunteers, community representatives and research staff. Data were managed using QSR Nvivo 10 and analysed using an inductive-deductive approach, guided by ethics literature. CHMI volunteers had reasonable understanding of the study procedures. Decisions to join were influenced by study incentives, trust in the research institution, their assessment of associated burdens and motivation to support malaria vaccine development. However, deliberate malaria infection was a highly unusual research strategy for volunteers, community representatives and some study staff. Volunteers’ experiences of physical, emotional and social burdens or harms were often greater than anticipated initially, and fluctuated over time, related to specific procedures and events. Although unlikely to deter volunteers' participation in similar studies in furture, we argue that the dissonance between level of understanding of the burdens involved and actual experiences are morally relevant in relation to community engagement, informed consent processes, and ongoing support for volunteers and research staff. We further argue that ethics oversight of CHMI studies should take account of these issues in deciding whether consent, engagement and the balance of benefits and harms are reasonable in a given context. 相似文献
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Nicholas Cianciotto Terry Serwold-Davis Neal Groman Giulio Ratti Rino Rappuoli 《FEMS microbiology letters》1990,66(1-3):299-301
Chromosomal restriction fragments of Corynebacterium ulcerans and C. diphtheriae, containing an integration site for corynephages of the beta family, show homology on Southern blots. Homologous DNA in also found in the soil isolate C. glutamicum, although this strain is not susceptible to beta-corynephages. Three of these DNA fragments, one for each bacterial strain, and a fragment of gamma-corynephage DNA previously shown to contain the phage integration site, were cloned and sequenced. Alignment of the 3 bacterial sequences shows a very high degree of homology in a stretch of ca 120 nucleotides, whereas the rest of the sequences is generally non-homologous. Within this common bacterial portion, a segment of ca. 96 nucleotides (core sequence) is also highly homologous to the phage sequence. The first half (ca. 50 bp) of the core sequence is identical in all aligned sequences whereas the second half, which is largely occupied by a stem-and-loop structure, contains point mutations peculiar to each clone. The described sequences are likely to be involved in phage integration/excision processes. 相似文献
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A phylogenetic analysis and revised classification of the Monocotylidae Taschenberg, 1879 (Monogenea) 总被引:1,自引:0,他引:1
The Monocotylidae Taschenberg, 1879 is revised based on a cladistic analysis of relationships between the constituent species and genera. The monophyly of the family is supported by three apomorphic character states: division of the haptor into one central and eight peripheral loculi; the ovary looping the right intestinal caecum; and tetrahedral eggs. The family is divided into six subfamilies: Calicotylinae Monticelli, 1903 (comprising Calicotyle Diesing, 1850, Dictyocotyle Nybelin, 1941); Dasybatotreminae Bychowsky, 1957 (comprising Anoplocotyloides Young, 1967, Dasybatotrema Price, 1938, Timofeevia n. g., Troglocephalus Young, 1967); Decacotylinae n. subfam. (comprising Decacotyle Young, 1967, Papillicotyle Young, 1967); Heterocotylinae n. subfam. (comprising Heterocotyle Scott, 1904, Neoheterocotyle Hargis, 1955, Nonacotyle Ogawa, 1991, Potamotrygonocotyle Mayes, Brooks & Thorson, 1981, Spinuris Doran, 1953); Merizocotylinae Johnston & Tiegs, 1922 (comprising Cathariotrema Johnston & Tiegs, 1922, Empruthotrema Johnston & Tiegs, 1922, Merizocotyle Cerfontaine, 1894, Squalotrema Kearn & Green, 1983, Triloculotrema Kearn, 1993); and Monocotylinae Taschenberg, 1879 (comprising Clemacotyle Young, 1967, Dendromonocotyle Hargis, 1955, Monocotyle Taschenberg, 1878). The Dendromonocotylinae Hargis, 1955 is removed from subfamilial status and the two genera previously assigned to the subfamily are reassigned to the Monocotylinae. Timofeevia is proposed for Timofeevia rajae (Timofeeva, 1983) n. comb. (formerly Dasybatotrema rajae). Mycteronastes Kearn & Beverley-Burton, 1990 and Thaumatocotyle Scott, 1904 are synonymised with Merizocotyle. Gymnocalicotyle Nybelin, 1941 is not considered a distinct taxon. Revised diagnoses and keys for subfamilies and genera of the Monocotylidae are provided. 相似文献
19.
R. Myles Riner Kathryn Maino Collins Garrett E. Foulke George V. Moorhead Phillip Terry 《The Western journal of medicine》1987,147(5):602-608
In a pilot project sponsored by the California State Emergency Medical Services Authority, validated, verifiable criteria were developed for the vertical categorization of hospital emergency services in 11 different groupings of medical and surgical emergencies. We describe the development of an assessment process and categorization criteria to identify the most appropriate receiving facility for interfacility transfer and, in selected instances, field triage of patients with different levels of severity of illness or injury. We propose that this facility assessment project be used in the critical care planning process for the eventual vertical categorization of hospital emergency services in California and as a template for similar projects in other states. 相似文献
20.
We have used the HLA-C-specific DNA probe pC250 to investigate restriction fragment length polymorphism (RFLP) at the HLA-C locus. Genomic Southern blot hybridization included DNA prepared from a panel of homozygous typing cells representing serological specificities Cw1 to Cw8 and also from samples representing Cw blanks. Although many restriction nucleases failed to reveal any polymorphism, RFLPs were evident with Taq I, Pvu II, Bst XI, Nde 1, and Nci I in addition to the previously reported Eco RI. In the case of Bst XI, a unique RFLP defined a subset of serologically defined Cw blanks. Comparison of RFLP sizes with restriction fragment lengths obtained from the known HLA-Cw3 gene sequence permitted the localization of intragenic C locus RFLLs and the identification of a variable Taq I site in the second intron, a variable Nci I site near the end of the fourth exon, and a variable Pvu lI site in the fifth intron. 相似文献