Notulae cucurbitologicae VI. Über einige Artkreuzungen in der GattungCucurbita     

Igor Grebenščikov 《Genetic Resources and Crop Evolution》1965,13(1):145-161

  相似文献   

肉类加工机刀具制造与修复的新方法     

Rudt.  FY Gut.  MSH 《华中农业大学学报》2000,19(3):292-295

Ｍａｎｙｔｏｏｌｓｓｕｃｈａｓｂｏｎｉｎｇｋｎｉｖｅｓ,ｍｅａｔｍｉｎｃｉｎｇｍａｃｈｉｎｅｃｒｏｓｓｋｎｉｖｅｓａｎｄｇｒａｔｅｓ,ｃｕｔｔｅｒｋｎｉｖｅｓｔｈａｔａｒｅｗｉｄｅｌｙｕｓｅｄｎｏｗａｄａｙｓｉｎｍｅａｔｐｒｏｃｅｓｓｉｎｇｉｎｄｕｓｔｒｙｈａｖｅｌｏｗｓａｆｅｔｙｉｎｄｅｘ.Ｉｎｔｈｉｓｃｏｎｎｅｃｔｉｏｎｉｔｂｅｃａｍｅｎｅｃｅｓｓａｒｙｔｏｉｍｐｒｏｖｅｃｕｔｔｉｎｇｔｏｏｌｓｂｙｉｎｃｒｅａｓｉｎｇｔｈｅｉｒｓａｆｅｔｙ.1　Ｍｅａｔｍｉｎｃｉｎｇｍａｃｈｉｎｅｃｒｏｓｓｋｎ…  相似文献   

Isolation of single human hematopoietic stem cells capable of long-term multilineage engraftment   总被引：1，自引：0，他引：1  

Notta F  Doulatov S  Laurenti E  Poeppl A  Jurisica I  Dick JE 《Science (New York, N.Y.)》2011,333(6039):218-221

Lifelong blood cell production is dependent on rare hematopoietic stem cells (HSCs) to perpetually replenish mature cells via a series of lineage-restricted intermediates. Investigating the molecular state of HSCs is contingent on the ability to purify HSCs away from transiently engrafting cells. We demonstrated that human HSCs remain infrequent, using current purification strategies based on Thy1 (CD90) expression. By tracking the expression of several adhesion molecules in HSC-enriched subsets, we revealed CD49f as a specific HSC marker. Single CD49f(+) cells were highly efficient in generating long-term multilineage grafts, and the loss of CD49f expression identified transiently engrafting multipotent progenitors (MPPs). The demarcation of human HSCs and MPPs will enable the investigation of the molecular determinants of HSCs, with a goal of developing stem cell-based therapeutics.  相似文献   

Cytobrushing of the oral mucosa as a possible tool for early detection of testudinid herpesvirus in Horsfield’s tortoises with nonspecific clinical signs     

Alessandro Vetere  Mara Bertocchi  Igor Pelizzone  Giuseppe F. La Cauza  Laura Denti  Enrico Bigliardi  Francesco Di Ianni 《Journal of veterinary diagnostic investigation》2021,33(1):116

Forty-five Horsfield’s tortoises (Testudo horsfieldii; syn. Agrionemys horfieldii, Russian tortoise) belonging to different owners had decreased appetite and respiratory issues. Twenty-nine tortoises had epiphora, dyspnea, and white necrotic diphtheroid oral plaques (group G1). Ten of the remaining 16 tortoises had serious dehydration, appetite disorder, and depression (G2). The last 6 tortoises had only decreased appetite and moderate conjunctival discharge (G3). During the physical examination of all 45 tortoises, a cytologic sample and an oral swab for herpesvirus and Mycoplasma agassizii PCR testing were taken. In 20 of 29 specimens from G1, in 8 of 16 from G2, and 0 of 6 from G3, the cytologic exam revealed intranuclear acidophilic inclusion bodies, multinucleate cellular syncytia, and further abnormalities caused by herpesviral infection. Moreover, all 45 tested subjects were found to be positive for testudinid herpesvirus 1; 2 were positive for M. agassizii. This prospective study suggests that Horsfield’s tortoises with such signs would benefit from this screening procedure, given that it was effective in a significant proportion of infected and symptomatic animals, and no negative effects were seen.  相似文献   

Über die Schätzung der Heritabilität im weiteren Sinne mit der anschaulichen Methode der Pfadanalyse     

Igor Grebenščikov 《Genetic Resources and Crop Evolution》1978,26(2):293-302

  相似文献   

Notulae cucurbitologicae VII     

Igor Grebenščikov 《Genetic Resources and Crop Evolution》1969,17(1):109-120

  相似文献   

Über verschiedenes genetisches Verhalten der F1-Heterosis- und F2-Abfallindizes bei Kreuzungen von Maisherkünften des Gaterslebener Sortimentes     

Igor Grebenščikov 《Genetic Resources and Crop Evolution》1973,21(1):10-24

Zusammenfassung Auf Grund von Material der 74 randomisierten Maiskreuzungen aus den Jahren 1965/1966 wurden frühere Ergebnisse des Autors (1962) über das Verhalten der F₁-Generationen bezüglich der meisten quantitativen Merkmale nach dem Mitscherlichschen Gesetz vom abnehmenden Ertragszuwachs bestätigt: je größer die absoluten Erträge der Eltern, desto kleiner die relativen Mehrerträge (Heterosiseffekte) der F₁-Generationen; die Korrelationskoeffizienten sind hier signifikant negativ. Dasselbe Kreuzungsmaterial zeigte aber, daß die relativen Mindererträge (Leistungsabfalleffekte) der F₂-Generationen diesem Gesetze nicht folgen, sondern von den absoluten Erträgen der Eltern praktisch unabhängig sind: hier erwiesen sich die Korrelationskoeffizienten als nicht signifikant von Null verschieden.Es wird auf die Ähnlichkeit dieser Korrelationen mit den genotypischen Streuungsanteilen der Abfalleffekte hingewiesen, was für die Brauchbarkeit der Heritabilitätsschätzung aus den Varianzkomponenten spricht.

---

On different genetical behaviour of the indices for heterosis in F₁ and for declining in F₂ in crosses between maizes of the Gatersleben collection

Summary Results of 74 random maize crosses from 1965 and 1966 confirmed the author's former results (1962) on the behaviour of F₁ generations in most quantitative characters according to the Mitscherlich law of reducing increase in yield: the higher the absolute yields of the parents, the lower the relative excess in yields (heterotic effects) of the F₁ generations. Here, the coefficients of correlation are significantly negative. The same material, however, proved that the relative decreases in yield (declining effects) of the F₂ generations do not correspond to this law but are practically independent on the absolute yields of the parents : Here, the coefficients of correlation turned out to be not significantly different from zero.The similarity of these correlations to the genotypic components of variance of the declining effects is indicated. This points to the usefulness of estimating heritability by the components of variance.

---

F₁ F₂

74 1965–1966 . (1962) , (F₁) : , ( ) F₁; ¶rt; . , ( F) (F₂) , : . ¶rt; ¶rt; , .

  相似文献   

Collateral arteries of the aortic arch of the red-rumped agouti (Dasyprocta leporina Linnaeus, 1758)     

Radan Elvis Matias de Oliveira  Herson da Silva Costa  Hélio Noberto de Araújo Júnior  Igor Renno Guimarães Lopes  Paulo Mateus Alves Lopes  João Vitor de Oliveira Gurgel  Moacir Franco de Oliveira 《Anatomia, histologia, embryologia》2020,49(3):417-424

Detailed knowledge of the arterial system is an important prerequisite when interpreting experimental data in research, as well as in the diagnosis of cardiovascular disease using imaging techniques such as Doppler echocardiography and contrast radiography. Thus, considering the importance of the aortic arrangement, the objective of this study was to describe the collateral arteries of the aortic arch of agoutis in order to establish the standard model, and therefore contribute to studies involving research related to heart disease, and produce information for a more accurate diagnosis in complementary imaging examinations. In this study, 14 adult animals were used, comprising eight males and six females. The vascular system was washed with 0.9% aqueous saline solution and perfused with Neoprene 450 latex coloured with yellow or red pigment, which was subsequently dissected and analysed. One male animal was used for the digital contrast radiography technique perfused with a liquid barium sulphate solution (Bariogel^®) (1 g/ml) and Neoprene 450 latex, both diluted 1/3. The aortic arch of the agouti presented with only the brachiocephalic trunk as collateral branch in all the animals studied. Thus, agouti falls into type 1 for mammalian aortic arch vascular arrangements.  相似文献   

The impact of publication on freshwater pearl mussel conservation: To conceal or to reveal the location of threatened habitats?     

Igor Popov 《水产资源保护:海洋与淡水生态系统》2020,30(9):1816-1820

• 1. The freshwater pearl mussel, Margaritifera margaritifera, is a threatened species. One of the threats faced by this species is direct extermination by poachers, and therefore some researchers conceal information on the locations of pearl mussel habitats. For example, some researchers do not publish the names of the rivers where pearl mussels occur, whereas other researchers do.
• 2. Concealing the names of rivers containing pearl mussels makes them unknown not only to potential offenders but also to administrators, nature conservation practitioners, and ordinary citizens. As a result, no protection measures are undertaken, which is all the more regrettable as damage to pearl mussel habitats can occur accidentally.
• 3. Concealing details of the location of pearl mussel habitats in publications has an adverse impact on the work of specialists, as they do not have access to enough information to study and analyse the biology and distribution of these molluscs.
• 4. One river with pearl mussels in the Gulf of Finland was initially described anonymously (as ‘River B’). Unfortunately, the river was subject to severe human impact, and the largest aggregation of pearl mussels was almost exterminated in the process of constructing a new electric supply line.
• 5. Concealing information on pearl mussel habitats in the Russian section of the Baltic Sea basin was also shown to have been a poor decision. Although the threat from potential poachers was insignificant because of the low commercial value of pearl mussels, the authorities remained uninformed about the existence of valuable habitats.
• 6. The question of whether the locations of pearl mussel habitats should be concealed or revealed in scientific publications does not have an unambiguous answer and should be considered on a case‐to‐case basis; however, the cases for which disclosure is reasonable seem to be more numerous.

  相似文献   

The growth and reproductive endocrinology of adult triploid Pacific salmonids     

Tillmann J. Benfey  Helen M. Dye  Igor I. Solar  Edward M. Donaldson 《Fish physiology and biochemistry》1989,6(2):113-120

This paper describes the effect of triploidy on growth and reproductive endocrinology in the months leading up to and including spawning in rainbow trout,Salmo gairdneri, and pink salmon,Oncorhynchus gorbuscha. Growth rates were the same for diploid and triploid rainbow trout, but triploid female pink salmon were smaller than maturing diploid females and diploid and triploid males of the same age. Triploid males of both species developed typical secondary sexual characteristics and had normal endocrine profiles, although their cycle appeared to be delayed by about one month. Triploid females remained silvery in appearance and showed no endocrine signs of maturation, even at the level of the pituitary. Thus, although triploids of both sexes are genetically sterile, only the females do not undergo physiological maturation.Reported in part at the Third International Symposium on Reproductive Physiology of Fish, St. John's, Newfoundland, August 2–7, 1987.  相似文献