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71.
FRANCES K. KUPICHA F.L.S. 《Botanical journal of the Linnean Society. Linnean Society of London》1975,70(3):231-242
The tribe Vicieae (Adanson) DC. ex Ser. is characterized by an unusual type of stele in which the lateral leaf-traces are present as cortical bundles in the internode below the insertion of their leaf. In most members of the tribe a completely fresh pair of cortical bundles is substituted at each node, but in ten species of Vicia L. there is only partial replacement. The group thus delimited also possesses some distinctive non-anatomical features.
The behaviour of the three leaf-traces at the node also varies throughout the tribe. This variation is shown to be correlated with differences in the shape of the stipules and their size in relation to the rest of the leaf. 相似文献
The behaviour of the three leaf-traces at the node also varies throughout the tribe. This variation is shown to be correlated with differences in the shape of the stipules and their size in relation to the rest of the leaf. 相似文献
72.
Anopheles gambiae sensu stricto Giles (Diptera: Culicidae) is the main malaria vector in sub‐Saharan Africa. Mated females show a circadian rhythm of spontaneous activity under constant environmental conditions that extends across the scotophase (subjective night). The effect of host‐associated cues [i.e. human foot odour supplemented with carbon dioxide (CO2)] on this nocturnal activity pattern is studied in laboratory‐reared A. gambiae s.s. M molecular form. Sixteen mated females (5–10 days old) are held in individual chambers (diameter 3.5 cm, length 4.5 cm) in a wind‐tunnel with a continuous flow (8.0 cm s?1) of clean air. At the onset of hours 3, 6 and 10 of the scotophase, their behaviour is recorded on video for 15 min in clean moving air and then for the next 15 min, with a specific treatment present in the clean airstream: (i) constant CO2 (4.8%) plus human odour; (ii) pulsed CO2 (5 s of every 30 s) plus human odour or (iii) control (clean air). Activities of individual mosquitoes are scored by direct observation of the video records for the incidents of ‘resting’, ‘walking’, ‘jumping’ and ‘flying’ in each of the 15‐min observation periods. There is a significant interaction between hour and treatment on mean changes in female activity level (P = 0.00004). Constant treatment increases the level of activity of A. gambiae females significantly, although only in hour 3 of the scotophase (P < 0.01), whereas pulsed and control treatments show no significant effect throughout the scotophase. Patterns of spontaneous activity in individual A. gambiae females thus appear to be modulated by host‐associated cues, resulting in a more active phase early in the night than might be expected from records of spontaneous activity under constant environmental conditions. Possible ecological and experimental implications of such an increase in activity are discussed in relation to host‐seeking behaviour. 相似文献
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74.
JOHN K. SCARIANO ALEXANDRA J. EMERY-COHEN GAVIN G. PICKETT MARILEE MORGAN PETER C. SIMONS FRANCES ALBA 《Journal of receptor and signal transduction research》2013,33(3):285-293
Bone marrow thymocytes in part mediate the bone-preserving effects of estrogen by decreasing their production of osteoclast growth factors such as interleukin-1 and -6 and tumor necrosis factor alpha in the presence of physiological amounts of estradiol. Although several in vitro studies implicate the T-lymphocyte as a candidate mediator of estrogen signaling in the skeleton, whether these cells or any lymphocytes ordinarily express one or both nuclear estrogen receptors was previously unresolved. The purpose of our investigation was therefore to ascertain, by using real-time PCR, immmunoblotting, and cytometric techniques, if any of the nuclear estrogen receptors could be detected in normal peripheral blood mononuclear cells (PBMNC) collected from healthy volunteers. The results of immunoblotting experiments revealed that both estrogen receptor alpha (ESR1) and beta (ESR2) proteins are expressed in nuclei, but not in the cytoplasm of PBMNC harvested from all of the 15 healthy male and female volunteers (aged 23–50 years) we tested. PBMNCs contained mRNA coding for the two major full-length isoforms of ESR2 and the expression of ESR2 protein was localized within a lymphocyte subpopulation by cytometric analysis. Our data provide further evidence that lymphocytes and monocytes are responsive to estrogen and underscore its importance in modulating the immune response, as well as the vascular and skeletal health of men and women. 相似文献
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77.
Induction of Unresponsiveness to Canine Renal Allografts by Total Body Irradiation and Bone Marrow Transplantation 总被引:1,自引:0,他引:1
FELIX T. RAPAPORT FRANCES D. CANNON DAVID A. BLUMENSTOCK KOJI WATANABE JOSEPH W. FERREBEE 《Nature: New biology》1972,235(58):191-192
RECENT progress in the definition of the DL-A antigens within a closely bred colony of beagles maintained at the Mary Imogene Basset Hospital (Cooperstown colony) has shown that these antigens are components of the principal system of histocompatibility (DL-A) in the dog1–3. Dausset and associates4 have described the segregation of DL-A antigens in 679 offspring of 151 consecutive matings within the Coopers-town colony. Through methods of backcross analysis, 23 DL-A haplotypes (that is, specificities determined by the DL-A region of one single chromosome) have been identified and the DL-A genotypes of 1,302 offspring of 517 matings in this colony have been defined4. This combined genetic and serological information has provided an opportunity to reassess the reported survival rates of allogeneic bone marrow transplantation in serologically matched littermate dogs5. We describe here the long term survival of bone marrow transplants and renal allografts obtained from the same donors in nine littermate and three non-littermate recipients selected on the basis of genetic and serological criteria of DL-A compatibility in the Cooperstown colony. The results are contrasted with the survival of twenty-two renal allografts performed in untreated recipients selected on the basis of similar criteria. 相似文献