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701.
E. B. Britton 《Australian Journal of Entomology》1988,27(1):27-36
Abstract
The tribe Heteronycini and 10 included genera (4 of them new) are defined. A key to genera and keys to species of Acheilo gen. n. and Webbella gen. n. are provided. The new genera are: Acheilo, Paraheteronyx, Proborhinus and Webbella. A. clypeatus gen. n., sp. n. is described.
The following species are transferred to other genera: Heteronyx bravicollis Blackburn, H. brevicoxis Lea, H. clypealis Lea, H. cribrifrons Lea, H. inconstans Lea, H. noctivagus Lea, H. phanophilus Lea, H. transversopolitus Lea and H. unidentatus Lea to Neoheteronyx Blackburn; H. unguiculatus Burmeister to Paraheteronyx gen. n.; H. cornutus Blackburn to Proborhinus gen. n.; H. capitalis Blackburn and H. pedarius Blackburn to Acheilo gen. n.; H. firmus Blackburn and H. labralis Blackburn to Webbella gen. n. Anacheirotus Blackburn is synonymised with Heteronyx Guérin-Méneville; A. inornatus Blackburn becomes H. inornatus (Blackburn). Pseudoheteronyx seticollis Lea is synonymised with P. creber Blackburn. Heteronyx clypealis Lea is synonymised with Neoheteronyx brevicollis (Blackburn). Lectotypes are designated for Heteronyx unguiculatus and Eurychelus marmoratus Blanchard. 相似文献
The tribe Heteronycini and 10 included genera (4 of them new) are defined. A key to genera and keys to species of Acheilo gen. n. and Webbella gen. n. are provided. The new genera are: Acheilo, Paraheteronyx, Proborhinus and Webbella. A. clypeatus gen. n., sp. n. is described.
The following species are transferred to other genera: Heteronyx bravicollis Blackburn, H. brevicoxis Lea, H. clypealis Lea, H. cribrifrons Lea, H. inconstans Lea, H. noctivagus Lea, H. phanophilus Lea, H. transversopolitus Lea and H. unidentatus Lea to Neoheteronyx Blackburn; H. unguiculatus Burmeister to Paraheteronyx gen. n.; H. cornutus Blackburn to Proborhinus gen. n.; H. capitalis Blackburn and H. pedarius Blackburn to Acheilo gen. n.; H. firmus Blackburn and H. labralis Blackburn to Webbella gen. n. Anacheirotus Blackburn is synonymised with Heteronyx Guérin-Méneville; A. inornatus Blackburn becomes H. inornatus (Blackburn). Pseudoheteronyx seticollis Lea is synonymised with P. creber Blackburn. Heteronyx clypealis Lea is synonymised with Neoheteronyx brevicollis (Blackburn). Lectotypes are designated for Heteronyx unguiculatus and Eurychelus marmoratus Blanchard. 相似文献
702.
703.
704.
Possible presence of DNA in intercellular bridges 总被引:1,自引:0,他引:1
705.
706.
Rick G. Kelsey William E. Wright Forrest Sneva Al Winward Carlton Britton 《Biochemical Systematics and Ecology》1983,11(4):353-360
The concentration of essential oils in big sagebrush foliage, Artemisia tridentata subsp. tridentata, subsp. vaseyana and subsp. wyomingensis collected from Oregon, differed significantly between individual shrubs with no correlation to geographic site, subspecies genotype, or plant age. Essential oil composition, measured by headspace analysis, was not affected by plant age, location of tissue within the crown, or geographic site. Six of 16 compounds differed quantitatively by subspecies, with wyomingensis and tridentata having nearly the same composition. Vaseyana could be recognized by its significantly lower concentration of acetone and methacrolein, two highly volatile, non-terpenoid, constituents. The implication of these results and those of recent studies are discussed in relation to herbivory. 相似文献
707.
S. J. Mather E. Ur J. Bomanji D. Ellison G. M. Besser K. E. Britton 《Cell biochemistry and biophysics》1992,21(1-3):93-107
Octreotide is a synthetic analog of the peptide hormone somatostatin (SMS). A wide variety of tumors express enhanced numbers of SMS receptors, notably neuroendocrine tumors and lymphomas, but also some of the more common adenocarcinomas. Octreotide contains only eight amino acids, some of which are in the (D) configuration in order to enhance the stability of the molecule in vivo. Tyrosine and ATPA-containing analogs of octreotide have been synthesized and labeled with iodine-123 and indium-111, respectively, with the intention of targeting SMS receptor-containing tumors for diagnostic purposes. Both radiopharmaceuticals demonstrate a high sensitivity and specificity for these tumors, indicating a clinical role for these agents in management of these diseases. Lessons can be learned from the success of these agents when designing improved antibody-based molecules. Tumor uptake of radiolabeled octreotide is very rapid, occurring within minutes of administration. Blood clearance is also rapid, such that tumors are soon visible even in areas of high blood background. An interesting finding has been the differences between the pharmacokinetics of the iodinated and indium-labeled species. Although the majority of123I-Tyr3-octreotide undergoes hepatobiliary excretion,111In-DTPAPhe1-octreotide is eliminated predominantly by the kidneys. These results suggest that the smallest possible antibody-like tracers are likely to have advantages over native immunoglobulins and conventionals Fab-like fragments. 相似文献
708.
The aim of this paper is to quantify the effect of small quantities of carbon monoxide on the facilitated diffusion of oxygen by haemoglobin in the steady state. It is the first phase in the study of a mathematical model for carbon monoxide poisoning. Here we extend the Wyman model for facilitated diffusion to the case in which there are two ligands. The equations are solved using an asymptotic technique developed by Murray. We obtain accurate analytic approximations for the biologically important quantities of the problem for various percentages of carbon monoxide. These are the concentrations of free oxygen, haemoglobin, oxyhaemoglobin and carboxyhaemoglobin, and hence the saturation of the protein and the facilitated oxygen flux. The major effect of very small quantities of carbon monoxide on the oxygen flux is shown. 相似文献
709.
A stochastic cellular automata model for the population dynamics of the army antEciton burchelli on Barro Colorado Island in Panama is set up. It is simulated on the computer and shown to give good agreement with biological
data. It is analysed using two approximations akin to the mean field approximation in statistical mechanics, and good agreement
with the simulations is obtained. Finally, the role of distance between successive statary phase bivouacs is discussed with
regard to the rate of colony growth.
There are two aspects of the biological system studied here that make it of general importance. First, the population is structured,
since the size of each colony of army ants is crucial. Second, the spatial behaviour of the population, as in many others,
is not diffusion-like, although it is random. This has implications for the kind of model that is chosen. 相似文献
710.
OBJECTIVE--To determine whether an intervention programme based on existing school and community resources can reduce school absence and improve participation in games lessons and sport in children with unrecognised or undertreated asthma. DESIGN--Parallel group controlled intervention study. SETTING--102 primary schools in Nottingham: 49 were randomised to receive the intervention and 53 to be control schools. SUBJECTS--All children aged 5 to 10 years with parent reported absence from school because of wheezing in the previous year and taking no treatment or beta agonists only. INTERVENTIONS--Children with asthma were referred to their general practitioner for assessment of symptoms and treatment. Teachers were given education on asthma by the school nurse in 44 of the 49 intervention schools. MAIN OUTCOME MEASURES--Changes in school absence and missed games and swimming lessons because of wheezing, and schools'' policy towards management of asthma in school. RESULTS--Of 17,432 children screened, 451 met the entry criteria--228 in intervention schools and 223 in control schools. 152 (67%) children in intervention schools visited their general practitioner, of whom 39 (26%) were given a new diagnosis of asthma and 58 (38%) had treatment for asthma increased or changed. Over the next academic year mean (SE) parent reported school absence due to wheezing fell significantly, but to a similar extent, in both intervention and control schools (0.82 (0.11) and 1.09 (0.21) weeks respectively). There was little change in school recorded absence or participation in games lessons and swimming lessons in either group. At the end of the study intervention schools were more likely to have improved aspects of management of asthma in school. CONCLUSION--The intervention resulted in a majority of children being assessed by their general practitioner and improved teachers'' understanding and management of asthma, but it did not result in any appreciable reduction in morbidity. 相似文献