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2.
Rau AR 《Science (New York, N.Y.)》1992,258(5087):1444-1451
Doubly excited states of atoms and ions in which two electrons are excited from the ground configuration display strong radial and angular electron correlations. They are prototypical examples of quantum-mechanical systems with strong coupling. Two distinguishing characteristics of these states are: (i) their organization into successive families, with only weak coupling between families, and (ii) a hierarchical nature of this coupling, with states from one family decaying primarily to those in the next lower family. A view of the pair of electrons as a single entity, with the electron-electron repulsion between them divided into an adiabatic and a nonadiabatic piece, accounts for many of the dominant features. The stronger, adiabatic part determines the family structure and the weaker, nonadiabatic part the excitation and decay between successive families. Similar considerations extend to three-electron atomic states, which group into five different classes. They are suggestive of composite models for quarks in elementary particle physics, which exhibit analogous groupings into families with a hierarchical arrangement of masses and electroweak decays. 相似文献
3.
Bianco D Armstrong PJ Washabau RJ 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2007,21(4):694-699
BACKGROUND: Glucocorticoids with or without other immunotherapy are the initial treatment of choice for dogs with severe immune-mediated thrombocytopenia (IMT). The majority of treated dogs will have improvements in platelet counts within 5 to 7 days of starting therapy, but complications from hemorrhage often occur before a response is seen. Human IV immunoglobulin (hIVIG) blocks Fc receptors on mononuclear phagocytic cells in dogs; it is used in people with idiopathic thrombocytopenic purpura. HYPOTHESIS: The purpose of this study was to describe adverse effects and benefit of hIVIG in addition to conventional immunosuppressive therapy in dogs with severe IMT. ANIMALS: Five client-owned dogs with severe primary IMT. METHODS: Case series. The hospital database was searched for dogs with primary IMT treated with hIVIG. RESULTS: No adverse effects were noted during or after hIVIG infusion in any treated dog. Over a 6-month follow-up, all dogs were clinically normal when using conventional immunosuppressive therapy. Human IVIG was administered 3 days after initiation of immunosuppressive therapy in 4 dogs, and, after 2 days, in 1 dog. In all dogs, the mean platelet counts pre- and 24 hours post-hIVIG infusion (0.28-0.76 g/kg) were 2,500/pL and 50,600/microL (62,750/microL for the 4 responders), respectively. One dog failed to respond as promptly to hIVIG (0.34 g/kg), and the platelet count increased to 66,000/microL after 9 days of immunosuppressive therapy. The mean duration of hospitalization post-hIVIG in all 5 dogs was 1.8 days (12 hours for responders), and the mean total length of hospitalization was 4.6 days (3.5 days for responders). Active hemorrhage resolved and no packed red blood cell transfusions were required after hIVIG infusion for responders. CONCLUSIONS AND CLINICAL IMPORTANCE: Human IVIG was well tolerated and appeared to be associated with rapid platelet count recovery and amelioration of clinical signs in most dogs with IMT. 相似文献
4.
Paoletti B Otranto D Weigl S Giangaspero A Di Cesare A Traversa D 《Research in veterinary science》2011,91(3):397-399
One hundred and eighty one cats living in central Italy were tested for the presence of Giardia and Cryptosporidium infection by IFAT test and specific PCRs. Overall eight (4.4%) samples were IFAT-positive for Giardia. All the IFAT-positive samples for Giardia scored positive for the PCRs, and three more samples IFAT-negative generated PCR products leading to a total 6.1% molecular positivity rate for Giardia. All the examined samples were negative for Cryptosporidium. Sequencing of samples molecularly positive to Giardia indicated that three cats harbored the zoonotic Giardia duodenalis Assemblage A, whereas all other positive animals were infected with the feline-specific G. duodenalis Assemblage F. Phylogenetic analysis carried out on the sequences obtained supported the clustering of the isolates within Assemblages A and F. The results here presented provide data on the occurrence of Giardia genotypes in cats living in close contact with humans highlighting the potential importance of this protozoan disease for the public health. 相似文献
5.
Horse gastrointestinal myiasis caused by larvae of Gasterophilus spp. (Diptera, Oestridae) flies has a worldwide distribution and, where present, it is primarily caused by larvae of Gasterophilus intestinalis and Gasterophilus nasalis. Other species, i.e., Gasterophilus inermis, Gasterophilus pecorum and Gasterophilus haemorrhoidalis, present in different or in the same regions of the gastrointestinal tract, were only occasionally reported in very limited areas of eastern European Countries and in central Italy. With the aim to contribute data on the species composition of Gasterophilus and on the seasonal variation of the infection pattern in southern Italy, 152 native horses were necropsied from January to December 2003 and Gasterophilus larvae were collected from the stomach, the small intestine and the rectum of each of them. On the whole, 125 (82.2%) horses were infected by larvae of Gasterophilus spp. and 214 second stage larvae (L2) and 13,342 third stage larvae (L3) collected. Five species of Gasterophilus were identified with the following prevalence: G. intestinalis=95.2%, G. nasalis=44.8%, G. inermis=15.2%, G. pecorum=2.6% and G. haemorrhoidalis=0.8%. L3 were retrieved throughout the observation period with the highest mean burdens from January to August 2003 while the lowest mean was registered from September to November 2003. L2 were collected in February-March 2003 and from September to December 2003. The majority of the animals (n=66, 43.4%) were infected with a single Gasterophilus species, however, 45 animals (29.6%) harboured 2 species, 12 animals (7.9%) 3 species and 2 animals (1.3%) 4 species. The trend of abundance in the L3 of G. intestinalis and G. nasalis, the most represented species, was highly concordant (r=0.5, p<0.001). A retrospective comparison of our results and of other data from four seasons of observation (1983-1986) in central Italy showed that the number of G. inermis, G. pecorum and G. haemorrhoidalis have been decreasing relative to G. intestinalis and G. nasalis which may suggest tendency toward the extinction of the three former species of Gasterophilus. 相似文献
6.
Gianluca Neglia Bianca Gasparrini Domenico Vecchio Marcello Rubessa Rossella Di Palo Luigi Zicarelli Giuseppe Campanile 《Tropical animal health and production》2010,42(6):1243-1247
The aim of this study was to evaluate the effect of exogenous progesterone supplementation on superovulatory response in buffaloes
that has undergone a multiple ovulation program. Fourteen Mediterranean buffaloes were divided into two groups and received
a 4-day decreasing dosage of an equal mixture of 500 IU of FSH and LH starting on day 8 of the cycle. In group A (n = 7) a progesterone-releasing intravaginal device was removed on day 8, whereas in group B (n = 7) it was left till day 10, when PGF2a {\hbox{PG}}{{\hbox{F}}_{{2}\alpha }} was administered. Eighty hours later, buffaloes were artificially inseminated and after 6 days they undergone uterine flushing.
A higher (P < 0.05) number of corpora lutea (8.3 vs. 5.7) and embryo/flushing/buffalo (2.3 vs. 1.3) were recorded in group B vs. group
A if responsive buffaloes are considered (n = 12) and the number of corpora lutea was highly correlated with the number of embryos (r = 0.65; P < 0.05). In conclusion, progesterone supplementation during the first 2 days of the superovulation treatment seems to enhance
the recovery rate in buffalo species. A high ovulation rate, associated with a high number of corpora lutea, can represent
a parameter for estimating embryo recovery. 相似文献
7.
Greco G Madio A Buonavoglia D Totaro M Corrente M Martella V Buonavoglia C 《Veterinary journal (London, England : 1997)》2005,170(3):65-350
A study was carried out in the South of Italy to assess the role of clostridia in neonatal diseases of lambs and kids. Eighty-seven lambs and 15 kids belonging to 25 flocks were examined and Clostridium perfringens was the microorganism most commonly identified. C. perfringens isolates were analysed by polymerase chain reaction (PCR), in order to determine the prevalence of the genes cpa, cpb, cpb2, etx, iap and cpe. The most prevalent toxin-type of C. perfringens was found to be type A found in 84% of the cases with clostridial enterotoxaemia. No C. perfringens type B, C or E were found. C. perfringens type D was isolated in 16% of the cases. About 24% of the isolates were cpb2 positive. The prevalence of cpb2 across the different C. perfringens types varied. The beta(2)-toxin gene cpb2 was detected in 4/21 (19%) type A isolates, in 1/2 type D isolates, and in 1/2 type DE (cpe-carrying type D) isolates. The high rate of positivity to cpb2 among the isolates suggests that a vaccine based on the beta(2)-toxin, should be included in the vaccination schedule of the animals to confer adequate protection and to prevent the disease. 相似文献
8.
Domenico Rongai Claudio Cerato Luca Lazzeri 《European journal of plant pathology / European Foundation for Plant Pathology》2009,124(4):613-619
This study examines the effects of a vegetable fungicide on sugar beet powdery mildew (Erysiphe betae) and cucumber powdery mildew (Erysiphe cichoracearum). The formulations consisting of a dispersion of Brassicaceae meal in vegetable or mineral oils on infected leaves of sugar beet, reared in the greenhouse, and of musk melons cultivated
under plastic tunnels, were tested in comparison to each oil taken separately. Both formulations containing Brassicaceae meals, caused 94% of conidia to be distorted while for the untreated group only 2% were distorted. Furthermore, the leaf
area infected by E. betae was 56% for untreated plants and 2.7 and 9.9% respectively, for plants treated with meal containing mineral and vegetable
oil. Vegetable oil considered separately or with Brassicaceae meals showed no phytotoxicity, while the formulations based on mineral oil showed a significantly lower fresh and dry weight
on tomato plants. The low level or absence of phytotoxicity of plants treated with vegetable oil formulations suggests that
to improve the efficacy of powdery mildew control, they could be used mixed with sulphur. The efficiency of the vegetable
formulations in the powdery mildew control observed during these trials encourages further investigation on other parasitic
fungi and foliar pathogens. 相似文献
9.
Summary Five samples of Aegilops ventricosa (2n=4x=28, genome formula DDNN) from different geographical origins, were crossed in a diallelic scheme. Metaphase I chromosome pairing of the hybrids, accounting for all the possible genetic combinations, was analysed. Only bivalents were formed in some hybrids, while multivalents were scored in other ones. Seed storage proteins, gliadins and albumins, were also analysed by means of polyacrylamide gel electrophoresis. Based on the presence of multivalents in hybrids, and on the differences in seed protein profiles, the samples could be grouped into two clusters. Meiosis was regular in hybrids obtained within samples of the same group, while multivalents were present in hybrids involving a sample of one group and one of the other. The evolutionary trends in Ae. ventricosa are discussed. 相似文献
10.
Resistance to blackleg and tuber soft rot in sexual and somatic interspecific hybrids with different genetic background 总被引:1,自引:0,他引:1
Domenico Carputo Teodoro Cardi Mario Speggiorin Astolfo Zoina Luigi Frusciante 《American Journal of Potato Research》1997,74(3):161-172
Diploid interspecific hybrids from crosses betweenSolanum tuberosum haploids andS. canasense, S. multidissectum, andS. tarijense, along with tetraploid and hexaploid somatic hybrids S.tuberosum (+)S. commersonii, were screened for resistance to blackleg and tuber soft rot byErwinia carotovora subsp.atroseptica andE. carotovora subsp.carotovora. Among the diploid hybrids, those involving clone mlt la of S.multidissectum and tar 2b ofS. tarijense yielded the highest number of genotypes resistant to both blackleg and tuber soft rot. By contrast, all the hybrids involving clone tar 1lb ofS. tarijense were susceptible to both bacterial diseases. As far as resistance of somatic hybrids is concerned, the most interesting genotype was the tetraploid one which showed resistance to both blackleg and tuber soft rot Significant correlations were found betweenE. carotovora subsp.atroseptica andE. carotovora subsp.carotovora both in resistance to blackleg and in resistance to tuber soft rot, suggesting that resistance to the two subspecies is controlled by the same gene/s or that the relevant genes are linked. On the other hand, correlations between blackleg and tuber soft rot were never significant, indicating that different mechanisms may control resistance in tuber and stems. Alternatively, the resistance could be controlled by the same gene/s under a different spatial/temporal expression pattern. Twelve diploid sexual hybrids and one tetraploid somatic hybrid were selected for resistance to blackleg and/or tuber soft rot and for tuber characteristics. 相似文献