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31.
Rebeca S. Khouri Selma M. Almeida-Santos Daniel S. Fernandes 《Anatomical record (Hoboken, N.J. : 2007)》2020,303(9):2485-2496
Amerotyphlops brongersmianus (Vanzolini, 1976) is distributed in Brazil from the Atlantic Rainforest to the Cerrado biome. Only few studies have focused on the gross anatomy, reproductive organs, and histological data of typhlopids. We accessed information from the anatomy of gonads of 95 individuals collected at different months in the Restinga de Jurubatiba National Park, Rio de Janeiro state, Brazil. This included histological sections of the testes, ductus deferens and sexual segment of kidney (SSK) in males, and oviducts in females, from which fecundity was determined. Results revealed a correlation between gross morphology and histology of the reproductive system. Testes volume increased during spermatogenesis, and the ductus deferens diameter increased with the presence of spermatozoa. Additionally, changes occurred in kidney morphology, which showed a smooth or rough surface, the latter corresponding to the development of the SSK. Spermatozoa were found inside the lumen of the SSK of some males. Females lacked left oviducts and showed changes in morphological and histological aspects of the right oviducts throughout the year. In summer and spring the uterus showed undeveloped structures, while during winter this organ showed conspicuously developed glands and appeared pleated and opaque upon gross examination. The infundibulum was pleated in most females throughout the year and one female had spermatozoon in a receptacle located in the posterior infundibulum. In spring, this organ was enlarged compared to winter, with a thinner epithelium. Fecundity corresponded to 7–11 eggs. 相似文献
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Eric Black-Maier MD Michael Rehorn MD Rahul Loungani MD Daniel J. Friedman MD Fawaz Alenezi MD Kyle Geurink MD Sean D. Pokorney MD James P. Daubert MD Albert Y. Sun MD Brett D. Atwater MD Kevin P. Jackson MD Donald D. Hegland MD Kevin L. Thomas MD Tristram D. Bahnson MD Michel G. Khouri MD Jonathan P. Piccini MD MHS 《Pacing and clinical electrophysiology : PACE》2020,43(9):913-921
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B-cell growth factor receptor expression and B-cell growth factor response of leukemic B cell precursors and B lineage lymphoid progenitor cells 总被引:8,自引:1,他引:8
Uckun FM; Fauci AS; Heerema NA; Song CW; Mehta SR; Gajl-Peczalska K; Chandan M; Ambrus JL 《Blood》1987,70(4):1020-1034
The purpose of this study was to analyze the expression of B cell growth factor (BCGF) receptors and to elucidate the biologic effects of biochemically purified natural BCGF at the B cell precursor stage of human B lineage lymphoid differentiation. The specific binding of radioiodinated high-mol-wt BCGF (125I-HMW-BCGF) and low-molecular-wt BCGF (125I-LMW-BCGF) to fresh marrow blasts from B cell precursor acute lymphoblastic leukemia (ALL) patients was initially investigated. The estimated number of radioiodinated BCGF molecules bound per blast ranged from undetectable to 24.3 X 10(3) for HMW-BCGF, and from 11.5 X 10(3) to 457.8 X 10(3) for LMW-BCGF. In 3H-TdR incorporation assays, 75% of cases showed a significant response to LMW-BCGF with a median stimulation index of 9.3. By comparison, only 33% of cases showed a significant response to HMW-BCGF with a median stimulation index of 2.4. Subsequently, B cell precursor colony assays were performed to assess and compare the biologic effects of BCGF on leukemic B lineage lymphoid progenitor cells. Among 28 cases studied, 57% responded to both HMW-BCGF and LMW-BCGF, 21% responded only to LMW-BCGF, and the remaining cases showed no proliferative response to either growth factor. The response patterns of virtually pure populations of FACS- sorted leukemic B cell precursors were essentially identical to the proliferative responses of unsorted leukemic B-cell precursors. Synergistic effects between HMW-BCGF and LMW-BCGF were observed in 80% of the cases that responded to both. The numbers of cell-bound radioiodinated BCGF molecules, the stimulation indices, as well as the number of B cell precursor colonies in BCGF-stimulated cultures showed a marked interpatient variation. Patients with structural chromosomal abnormalities (SCAs) involving 12p11-13 or patients with a Philadelphia chromosome showed a greater HMW-BCGF response at the level of leukemic progenitor cells than did other patients (P = .02). The LMW-BCGF response was significantly greater for patients with SCA than for patients without SCA (P = .04). The response of leukemic progenitor cells to HMW-BCGF or LMW-BCGF did not correlate with sex, age, disease status, FAB morphology, WBC at diagnosis, or immunophenotype. To our knowledge, this study represents the first detailed analyses of BCGF receptor expression and BCGF effects in B cell precursor ALL. The data presented provide direct evidence for the expression of functional receptors for both HMW-BCGF and LMW-BCGF in B cell precursor ALL. 相似文献
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Qaiser Shafiq George V. Moukarbel Rajesh Gupta Dawn-Alita Hernandez Samer J. Khouri 《Journal of Echocardiography》2016,14(4):146-155
Acute pulmonary embolism remains a common cause of mortality. Early diagnosis and appropriate risk stratification is necessary to individualize treatment strategy. Computed tomography scan of the pulmonary arteries is routinely used to diagnose acute pulmonary embolism and in some cases is useful to assess right ventricular dilation. In patients with acute pulmonary embolism, right ventricular dilation and dysfunction indicates a high-risk situation where immediate administration of thrombolytic agent, catheter-directed thrombolysis, or surgical embolectomy could be considered. A bedside 2D echocardiogram at the time of presentation could provide additional morphological, functional, and hemodynamic parameters including right ventricular dilation, McConnell’s sign, reduced tricuspid annular plane systolic excursion (TAPSE), interventricular septal flattening, abnormal right ventricular hemodynamics and in rare cases thrombi in the inferior vena cava, right atrium or ventricle en route to pulmonary arteries may also be visualized. This additional information is useful for selection of appropriate treatment modality. Thus, our objective is to provide a practical echocardiographic approach for risk stratification of patients with acute pulmonary embolism. 相似文献
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A long‐acting pegylated recombinant human growth hormone (Jintrolong®) in healthy adult subjects: Two single‐dose trials evaluating safety,tolerability and pharmacokinetics 下载免费PDF全文
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Evaluation of a new enzyme-linked immunosorbent assay test for rotavirus antigen in faeces 总被引:6,自引:0,他引:6 下载免费PDF全文
A new commercial test for the diagnosis of rotavirus gastroenteritis was assessed. With some modifications it compared favourably with electron microscopy and immunofluorescence. 相似文献