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991.
Brncić N Mijandrusić-Sincić B Perić R Milić S Gorup L Mazur-Grbac M 《Collegium antropologicum》2010,34(Z2):267-269
Splenic rupture is rare but life threatening complication of mononucleosis syndrome. It has been suggested that subcapsular splenic hematoma formation precedes rupture. The case of 44-year-old, previously healthy, male with splenic hematoma occurring after rising of heavy cargo is reported. Mononucleosis syndrome was suggested based on routine laboratory tests (elevated white blood cell count with predominance of lymphocytes and raised serum transaminases) and CMV infection was confirmed by serological test. Nonoperative management was used since the patient was hemodynamically stable with no further signs of splenic rupture. The same approach has been used in growing number of cases of patients with spontaneous splenic rupture in mononucleosis syndrome. Importance of considering splenic hematoma and/or rupture if abdominal pain occurs in the course of mononucleosis syndrome is outlined as well as importance of routine laboratory tests in suspecting mononucleosis syndrome in otherwise clinically silent patient. 相似文献
992.
Gerlind U. C. Lehmann Sandra Berger Johannes Strauß Arne W. Lehmann Hans-Joachim Pflüger 《Journal of comparative physiology. A, Neuroethology, sensory, neural, and behavioral physiology》2010,196(11):807-816
Reduction of tympanal hearing organs is repeatedly found amongst insects and is associated with weakened selection for hearing.
There is also an associated wing reduction, since flight is no longer required to evade bats. Wing reduction may also affect
sound production. Here, the auditory system in four silent grasshopper species belonging to the Podismini is investigated.
In this group, tympanal ears occur but sound signalling does not. The tympanal organs range from fully developed to remarkably
reduced tympana. To evaluate the effects of tympanal regression on neuronal organisation and auditory sensitivity, the size
of wings and tympana, sensory thresholds and sensory central projections are compared. Reduced tympanal size correlates with
a higher auditory threshold. The threshold curves of all four species are tuned to low frequencies with a maximal sensitivity
at 3–5 kHz. Central projections of the tympanal nerve show characteristics known from fully tympanate acridid species, so
neural elements for tympanal hearing have been strongly conserved across these species. The results also confirm the correlation
between reduction in auditory sensitivity and wing reduction. It is concluded that the auditory sensitivity of all four species
may be maintained by stabilising selective forces, such as predation. 相似文献
993.
Sandra Maria Alvarenga Gomes Julio Antonio Lombardi 《Plant Systematics and Evolution》2010,289(1-2):13-33
The current classification systems recognize Salacioideae as a monophyletic group within Celastraceae. Nonetheless, some divergences exist for genera: in some cases, most species of the subfamily have been included in only two genera; in others, these genera have been subdivided. This study characterizes the leaf anatomy of 31 species of the subfamily Salacioideae as a contribution to identifying them through features that may also help distinguish among genera. Cross-sections of the median region of the leaf blade and of the petiole and dissociated and macerated epidermis were analyzed. Taxonomically relevant anatomical characters include the type of crystals in the parenchymatous tissue (monocrystals in Cheiloclinium and druses in other genera); the presence of laticifers in Cheiloclinium and Tontelea only; the variable form of the petiole vascular system among studied species; the type of stomata (cyclocytic with two concentric circles of subsidiary cells in P. dulcis; anomocytic in T. attenuata, T. fluminensis, and T. leptophylla; laterocytic in C. anomalum and C. hippocrateoides; and ciclocytic in the other species); the sinuosity of the anticlinal walls of the epidermal cells (sinuous in Cheiloclinium and Peritassa, except P. laevigata, and in S. arborea, S. insignis, S. mosenii, S. nemerosa, and S. opacifolia, and straight in all other studied species); the presence of crystalliferous idioblasts in the epidermis of P. dulcis, P. flaviflora, and P. mexiae; and the presence, form, and disposition of sclereids in the leaf blade, which is a highly variable character among the studied species. 相似文献
994.
Emanuela Signori Sandra Iurescia Emanuela Massi Daniela Fioretti Pieranna Chiarella Mariangela De Robertis Monica Rinaldi Giancarlo Tonon Vito Michele Fazio 《Cancer immunology, immunotherapy : CII》2010,59(10):1583-1591
After more than 15 years of experimentation, DNA vaccines have become a promising perspective for tumour diseases, and animal models are widely used to study the biological features of human cancer progression and to test the efficacy of vaccination protocols. In recent years, immunisation with naked plasmid DNA encoding tumour-associated antigens or tumour-specific antigens has revealed a number of advantages: antigen-specific DNA vaccination stimulates both cellular and humoral immune responses; multiple or multi-gene vectors encoding several antigens/determinants and immune-modulatory molecules can be delivered as single administration; DNA vaccination does not induce autoimmune disease in normal animals; DNA vaccines based on plasmid vectors can be produced and tested rapidly and economically. However, DNA vaccines have shown low immunogenicity when tested in human clinical trials, and compared with traditional vaccines, they induce weak immune responses. Therefore, the improvement of vaccine efficacy has become a critical goal in the development of effective DNA vaccination protocols for anti-tumour therapy. Several strategies are taken into account for improving the DNA vaccination efficacy, such as antigen optimisation, use of adjuvants and delivery systems like electroporation, co-expression of cytokines and co-stimulatory molecules in the same vector, different vaccination protocols. In this review we discuss how the combination of these approaches may contribute to the development of more effective DNA vaccination protocols for the therapy of lymphoma in a mouse model. 相似文献
995.
Sandra J. McInnes 《Polar Biology》2010,33(1):59-70
Echiniscus corrugicaudatus sp. nov., (Heterotardigrada; Echiniscidae) was found in the limited vegetation from the inland nunataks of Ellsworth Land,
West Antarctica. The tardigrade fauna of this a rarely explored region shows limited overlap with the fauna from the maritime
or coastal continental Antarctic. This species is placed within the Echiniscus “arctomys-group” based on the characteristic of, “a lack of body appendages other than cirrus A”. It has less well-defined edges to
the dorsal plates than other species within the group and distinct ridges on the caudal plate. Males were found in the population
indicating gonochoristic reproduction, and a large number of juveniles suggesting an over-wintering strategy of eggs or a
biennial population over-wintering as adults/sub-adults and eggs. 相似文献
996.
Korolyov A Dorbes S Azéma J Guidetti B Danel M Lamoral-Theys D Gras T Dubois J Kiss R Martino R Malet-Martino M 《Bioorganic & medicinal chemistry》2010,18(24):8537-8548
A convenient route for the synthesis of some acyloxymethyl esters and carboxamides of levofloxacin (LV) with modulated lipophilicity is described. The synthesized compounds were evaluated in vitro for their growth inhibitory effect in five human cancer cell lines. The most efficient LV derivatives (ester 2e and amide 4d) displayed IC(50) values in the 0.2-2.2 μM range, while IC(50) values for parent LV ranged between 70 and 622 μM depending on the cell line. The esters displayed no in vivo toxicity up to 80 mg/kg when administered intraperitoneally. This study thus shows that LV analogs displayed antitumor efficacy, at least in vitro, a feature that appeared to be independent from the lipophilicity of the grafted substituent. 相似文献
997.
Lactoferrin (Lf) is a mammalian exclusive protein widely distributed in milk and exocrine secretions exhibiting multifunctional
properties. Many of the proven or proposed functions of Lf, apart from its iron binding activity, depend on its capacity to
bind to other macromolecules. Lf can bind and sequester lipopolysaccharide (LPS), thus preventing pro-inflammatory pathway
activation, sepsis and tissue damage. However, the interplay between Lf and LPS is complex, and may result in different outcomes,
including both suppression of the inflammatory response and immune activation. These findings are critically relevant in the
development of Lf-based therapeutic interventions in humans. Understanding the molecular basis and functional consequences
of Lf-LPS interaction will provide insights for determining its role in health and disease. 相似文献
998.
999.
Krešimir Benci Karlo Wittine Malajka Radan Mario Cetina Mirela Sedić Sandra Kraljević Pavelić Krešimir Pavelić Erik De Clercq Mladen Mintas 《Bioorganic & medicinal chemistry》2010,18(17):6249-6257
A series of the novel acyclic unsaturated pyrimidine (1–12) and adenine (13) nucleoside analogues bearing conformationally restricted (Z)-2′-butenyl moiety were synthesized and evaluated for their antiviral and cytostatic activity potency against malignant tumor cell lines and normal human fibroblast (WI38). The N-1 and/or N-3 acyclic side chain substitution in pyrimidine ring in N-3 substituted 5-trifluoromethyluracil derivative (11), N-1, N-3 disubstituted 5-fluorouracil derivative (12) and adenine derivative (13) was deduced from their 1H and 13C NMR spectra and confirmed by single crystal X-ray structure analysis. The X-ray crystal structure analysis 11–13 revealed also supramolecular self-assemblies, in which infinite chains or dimers built two- and three-dimensional networks. The results of the in vitro cytostatic activity evaluations of 1–13 indicate that the majority of the compounds tested exhibited a non-specific and moderate antiproliferative effect at the highest concentration (100 μM). Of all evaluated compounds on the cell lines tested only the N-1 4″-fluoro-substituted-benzamide uracil derivative (7) showed rather marked and selective inhibitory activity against the growth of MCF-7 cells at a concentration of 2.7 μM and no cytotoxic effect on normal fibroblasts WI38. This compound can be therefore considered as a potential antitumor lead compound for further synthetic structure modification. 相似文献
1000.