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201.
Thomas L. Rost 《Protoplasma》1971,73(3-4):475-479
Summary Endosperm protein bodies are membrane bound. Internally, each body shows a pattern of dark and light concentric layers. A median dense core may also be present. These bodies stain for protein with mercuric bromphenol blue, but not for acid phosphatase.Based on a portion of a dissertation submitted to the Graduate College of Iowa State University in partial fulfillment of the requirements for the Ph. D. degree. 相似文献
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Parker M. Pennington PhD Kira L. Marshall MS Jonnie M. Capiro MS Lauren Howard DVM Barbara S. Durrant PhD 《Zoo biology》2020,39(2):141-144
All extant species in the Rhinocerotidae family are experiencing escalating threats in the wild, making self-sustaining captive populations essential genetic reservoirs for species survival. Assisted reproductive technologies (ARTs) will become increasingly important for achieving and maintaining ex situ population sustainability and genetic diversity. Previous reports have shown that a large proportion of captive southern white rhinoceros (SWR) females are irregularly cyclic or acyclic, and that cycling females display two different estrous cycle lengths of approximately 30 or 70 days. It has been suggested that the longer estrous cycle length is infertile or subfertile, as no term pregnancies have been observed following long cycles. Here we report the achievement of two pregnancies following long luteal phases, using ovulation induction and artificial insemination with either fresh or frozen-thawed semen. One female SWR conceived on the first insemination attempt and gave birth to a live offspring. A second female conceived twice in consecutive long cycles although the first embryo was resorbed by 33 days post-insemination. A pregnancy from this female's second insemination is ongoing with expected parturition in November 2019. Whether prolonged estrous cycles in SWR are subfertile or infertile in natural breeding situations remains unclear. However, our findings demonstrate that the application of ARTs following prolonged cycles can result the successful establishment of pregnancies in SWR. Therefore, with ARTs, female SWR otherwise considered nonreproductive due to long estrous cycles may still have the potential for representation and contribution to the ex situ population. 相似文献
205.
Genotoxicity of diacetoxyscirpenol (DAS) was studied on laboratory mice after intraperitoneal injection with single and repeated
doses. DAS was administrated at three different dose levels (0.5, 0.75, and 1.0 mg/kg body weight). The study was conducted
on both somatic and germ cells additional to the sperm morphology analysis. DAS treatment resulted in a significant reduction
(P<0.01) in mitotic activity at all levels of doses tested, confirming that DAS is a potent protein and DNA synthesis inhibitor.
At somatic cells (bone marrow) both structural and numerical chromosome abnormalities were observed. Single dose treatment
showed significant abnormalities only with high dose treatment. In contrast, at repeated dose similar abnormalities were also
observed with some significance but no systematic relation between the administrated dose and abnormalities ratio could be
settled. In germ cells (testicles), structural and numerical abnormalities were also observed. In general, the frequencies
of scored abnormalities at germ cells were lower than that the somatic cells. Sperm count test revealed a decrease in the
number of released sperm after toxin treatment. Abnormalities of sperm shape (head and tail) were observed, confirming the
positive correlation between cytogenetic damage and sperm abnormality.
The results also proved that DAS is a very toxic mycotoxin, in addition to inducing chromosomal abnormalities, it causes a
severe inhibition of DNA synthesis which subsequently affects the cell cycle and cell division. A good system for good harvesting
practice and good food technology can lower the risk for the consumers. 相似文献
206.
Perlík F Masri MA Rost M Kamarád V 《Biomedical papers of the Medical Faculty of the University Palacky, Olomouc, Czechoslovakia》2005,149(2):309-313
Cyclosporine A (CyA) is a standard component of immunosuppressive regimens. It is a critical-dose drug for which a minor change in absorption can have important clinical consequences. The aim of the study was to compare the pharmacokinetics and safety of the new generic CyA formulation, Equoral capsules, after a switch from original formulation, Neoral capsules, in seventy stable adult renal transplant recipients. The extent and rate of pharmacokinetic parameters for bioequivalence were compared in a non-randomized, steady-state clinical study with fixed non-replicate study design. Pharmacokinetic analysis of CyA have shown that both the rate and extent of absorption of Equoral does not differ significantly from that of Neoral. At identical dosing, the new formulation was found to have geometric means of C(max) 717 ng/ml and AUCtau 3108 ng/ml.h, while corresponding results of comparator were 725 ng/ml and AUCtau 3039 ng/ml.h, respectively. The 90 % confidence intervals of C(max) and AUCtau were within 80- 125 % interval of the mean values. The results suggest that Equoral capsules can be used as an alternative treatment to Neoral capsules in CyA regimen. 相似文献
207.
Zusammenfassung Die durch enzymatische Lyse der Zellwand erhaltenen Protoplasten verschiedener Hefen waren lebensfähig. Sie zeigten in Nährmedien, die zur Stabilisation der Protoplasten KCl enthielten, Wachstumserscheinungen.In flüssigen Medien war eine Regeneration zur intakten Hefezelle und damit eine Neusynthese der Zellwand nicht möglich. Die Protoplasten blieben osmotisch labil und lysierten in Aqua dest. Die nach mehrstündiger Kultur gebildeten Membranen waren nicht in der Lage, die Funktionen der Zellwand zu übernehmen.Durch Kultivieren in 80% iger Bierwürzegelatine konnten die Protoplasten jedoch zu Hefezellen mit intakter Zellwand regenerieren. Die entstandenen Hefezellen besaßen bezüglich ihrer Gärungseigenschaften die gleichen Merkmale wie die Ausgangshefen. Nur Protoplasten mit einem Kern waren zur Regeneration fähig.Während des Wachstums der Protoplasten ging der Vermehrung der Cytoplasmabestandteile eine Anreicherung des DNA-haltigen Materials parallel. Diese drückte sich in einer Vervielfachung der Kernzahl aus. Eine Bestimmung des Nucleinsäuregehaltes wachsender Protoplasten ergab, daß sich nach 12 stündiger Kultur der Gehalt an DNA auf etwa das Fünffache erhöht hatte, während der RNA-Gehalt nur um etwa das 2,5fache gestiegen war. Das Verhältnis RNA/DNA verschob sich demgemäß im Verlaufe des Wachstums immer mehr zugunsten der DNA. 相似文献
208.
Primary root growth dynamics and lateral root development of dark- and light grown cotton seedlings (Gossypium hirsutum L., cv. Acala SJ-2) were studied under control and salinity stress conditions. The seedlings were grown by two methods: A) in paper-lined, vermiculite-filled beakers with the plants growing between the paper and the glass wall (Gladish and Rost, 1993), and B) in hydroponics after germination and initial growth in germination paper rolls saturated with the treatment solutions (Kent and Läuchli, 1985). After germination, daily primary root elongation rate gradually incrased to a maximum, then gradually declined to close to zero for dark-grown seedlings, or to sustained rates of about 10 mm per day for light-grown control plants. Salinity stress delayed primary root growth and reduced peak elongation rates, without changing the general primary root growth pattern. These results suggest that salinity changed the time-scale, but did not modify the normal developmental sequence. Lateral root growth was more inhibited by salinity than primary root growth. In addition, elongation of lateral roots was more inhibited by salinity than their initiation and emergence. Light exposure of the shoot favored both sustained primary root growth from 7 days after planting, and lateral root emergence and growth. Salinity effects were more severe on seedlings germinated and grown in hydroponics (method B) than on vermiculite-grown plants (method A). These results emphasize the importance of growing conditions for the NaCl-induced effects on cotton root development. In addition, the differential effects of salinity on primary and lateral roots became evident, pointing to diverse control mechanisms for the development of these root types. 相似文献
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Central CCL2 signaling onto MCH neurons mediates metabolic and behavioral adaptation to inflammation 下载免费PDF全文
Ophélia Le Thuc Céline Cansell Miled Bourourou Raphaël GP Denis Katharina Stobbe Nadège Devaux Alice Guyon Julie Cazareth Catherine Heurteaux William Rostène Serge Luquet Jean‐Louis Nahon Carole Rovère 《EMBO reports》2016,17(12):1738-1752
Sickness behavior defines the endocrine, autonomic, behavioral, and metabolic responses associated with infection. While inflammatory responses were suggested to be instrumental in the loss of appetite and body weight, the molecular underpinning remains unknown. Here, we show that systemic or central lipopolysaccharide (LPS) injection results in specific hypothalamic changes characterized by a precocious increase in the chemokine ligand 2 (CCL2) followed by an increase in pro‐inflammatory cytokines and a decrease in the orexigenic neuropeptide melanin‐concentrating hormone (MCH). We therefore hypothesized that CCL2 could be the central relay for the loss in body weight induced by the inflammatory signal LPS. We find that central delivery of CCL2 promotes neuroinflammation and the decrease in MCH and body weight. MCH neurons express CCL2 receptor and respond to CCL2 by decreasing both electrical activity and MCH release. Pharmacological or genetic inhibition of CCL2 signaling opposes the response to LPS at both molecular and physiologic levels. We conclude that CCL2 signaling onto MCH neurons represents a core mechanism that relays peripheral inflammation to sickness behavior. 相似文献