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651.
Polymorphism and pair formation in the mosquitofish Gambusia holbrooki (Pisces: Poeciliidae) 总被引:1,自引:0,他引:1
Synopsis Pair formation was studied in a polymorphic population of Gambusia holbrooki in a brackish drainage canal in Southern Florida. All females and the majority of males were gray colored and only 5% of the males were black spotted. A small fraction of the population formed pairs, composed of a female and a male that swam synchronously and close together for several minutes. During pairing the male often achieved gonopodial contact with the female. Black spotted males occurred in pairs ten fold more frequently than expected under random pairing. The major behavioral mechanism accounting for the disproportionate occurrence of spotted males in pairs is, probably, the preference of females for these males. 相似文献
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Ashraf Nida Kubat Ryan C. Poplin Victoria Adenis Antoine A. Denning David W. Wright Laura McCotter Orion Schwartz Ilan S. Jackson Brendan R. Chiller Tom Bahr Nathan C. 《Mycopathologia》2020,185(5):843-865
Mycopathologia - Endemic mycoses such as histoplasmosis, coccidioidomycosis, blastomycosis, paracoccidioidomycosis, and talaromycosis are well-known causes of focal and systemic disease within... 相似文献
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Katayun Cohen-Kashi Malina Emmanouil Tsivourakis Dahlia Kushinsky Daniella Apelblat Stav Shtiglitz Eran Zohar Michael Sokoletsky Gen-ichi Tasaka Adi Mizrahi Ilan Lampl Ivo Spiegel 《Neuron》2021,109(13):2150-2164.e5
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655.
Dov Malonek Ben‐Zion Dekel Gabi Haran Renat Reens‐Carmel Gabriel M. Groisman Mordechai Hallak Ilan Bruchim 《Journal of biophotonics》2020,13(9)
A rapid and reliable intraoperative diagnostic technique to support clinical decisions was developed using Fourier‐transform infrared (FTIR) spectroscopy. Twenty‐six fresh tissue samples were collected intraoperatively from patients undergoing gynecological surgeries. Frozen section (FS) histopathology aimed to discriminate between malignant and benign tumors was performed, and attenuated total reflection (ATR) FTIR spectra were collected from these samples. Digital dehydration and principal component analysis and linear discriminant analysis (PCA‐LDA) models were developed to classify samples into malignant and benign groups. Two validation schemes were employed: k‐fold and “leave one out.” FTIR absorption spectrum of a fresh tissue sample was obtained in less than 5 minutes. The fingerprint spectral region of malignant tumors was consistently different from that of benign tumors. The PCA‐LDA discrimination model correctly classified the samples into malignant and benign groups with accuracies of 96% and 93% for the k‐fold and “leave one out” validation schemes, respectively. We showed that a simple tissue preparation followed by ATR‐FTIR spectroscopy provides accurate means for very rapid tumor classification into malignant and benign gynecological tumors. With further development, the proposed method has high potential to be used as an adjunct to the intraoperative FS histopathology technique. 相似文献
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Ziv Alperovich Oshrat Cohen Yossi Muncher Ilan Ben-Oren Wacław Kuczmik Wojciech Zelawski Amiel A. Ishaaya 《Journal of biophotonics》2021,14(3):e202000185
The current laser atherectomy technologies to treat patients with challenging (to-cross) total chronic occlusions with a step-by-step (SBS) approach (without leading guide wire), are lacking real-time signal monitoring of the ablated tissues, and carry the risk for vessel perforation. We present first time post-classification of ablated tissues using acoustic signals recorded by a microphone placed nearby during five atherectomy procedures using 355 nm solid-state Auryon laser device performed with an SBS approach, some with highly severe calcification. Using our machine-learning algorithm, the classification results of these ablation signals recordings from five patients showed 93.7% classification accuracy with arterial vs nonarterial wall material. While still very preliminary and requiring a larger study and thereafter as commercial device, the results of these first acoustic post-classification in SBS cases are very promising. This study implies, as a general statement, that online recording of the acoustic signals using a noncontact microphone, may potentially serve for an online classification of the ablated tissue in SBS cases. This technology could be used to confirm correct positioning in the vasculature, and by this, to potentially further reduce the risk of perforation using 355 nm laser atherectomy in such procedures. 相似文献
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Sanford Garfield Joseph Ilan 《Biochimica et Biophysica Acta (BBA)/General Subjects》1976,444(1):154-163
Galactosyltransferase specific activities in embryonic chick retina, optic tectum, and telecephalon were found to decline during embryonic development. Incorporation of galactose from nucleotide sugar into exogenously added glycoprotein acceptor was measured in the presence of excess of glycoprotein acceptor. This ensured that the specific activity measurements were reflections of true enzyme specific activity rather than availability of acceptor. Moreover, we have shown that the decline in specific activity is not due to degradation of the nucleotide sugar, UDP-galactose, under our in vitro assay conditions.Enzymatic specific activity declined sharply with embryonic age for all tissues tested. This decline was not affected by the presence of 5-bromodeoxyuridine during in vitro culture of embryonic chick neutral retina above that caused by the culturing alone. Galactosyltransferase activity was not found to be associated with the plasma membrane fraction from homogenized tissue but rather with the microsomal fraction. Thus, the changes in galactosyltransferase specific activity detected here do not reflect changes at the cell surface. 相似文献