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排序方式: 共有331条查询结果,搜索用时 13 毫秒
71.
A gully pot is often cleaned with the help of an eductor truck, which uses hydrodynamic pressure and a vacuum to loosen and remove the solids and standing liquid from a gully pot. This paper considers the polycyclic aromatic hydrocarbons (PAH) content in the gully pot mixture (water and sediment) after it has been discharged from the eductor truck. The results show that most PAH was attached to particles, and the dissolved phase represented approximately 22% of the total water concentration. No significant difference was found for the water phase between a housing area and a road, whereas a significant difference was found for NAP, ACE, FL, ANT, FLR, PYR, BaF, and BPY in the sediment at a 95% confidence level. Source identification showed that the PAH in the gully pot mixture came from mixed sources. Both the water and sediment phase exceed all or some of the compared guidelines. The result from this paper shows that not only the sediment needs to be discussed, but also the water phase created during the maintenance of different BMPs. 相似文献
72.
Arensburger P Megy K Waterhouse RM Abrudan J Amedeo P Antelo B Bartholomay L Bidwell S Caler E Camara F Campbell CL Campbell KS Casola C Castro MT Chandramouliswaran I Chapman SB Christley S Costas J Eisenstadt E Feschotte C Fraser-Liggett C Guigo R Haas B Hammond M Hansson BS Hemingway J Hill SR Howarth C Ignell R Kennedy RC Kodira CD Lobo NF Mao C Mayhew G Michel K Mori A Liu N Naveira H Nene V Nguyen N Pearson MD Pritham EJ Puiu D Qi Y Ranson H Ribeiro JM Roberston HM Severson DW Shumway M 《Science (New York, N.Y.)》2010,330(6000):86-88
Culex quinquefasciatus (the southern house mosquito) is an important mosquito vector of viruses such as West Nile virus and St. Louis encephalitis virus, as well as of nematodes that cause lymphatic filariasis. C. quinquefasciatus is one species within the Culex pipiens species complex and can be found throughout tropical and temperate climates of the world. The ability of C. quinquefasciatus to take blood meals from birds, livestock, and humans contributes to its ability to vector pathogens between species. Here, we describe the genomic sequence of C. quinquefasciatus: Its repertoire of 18,883 protein-coding genes is 22% larger than that of Aedes aegypti and 52% larger than that of Anopheles gambiae with multiple gene-family expansions, including olfactory and gustatory receptors, salivary gland genes, and genes associated with xenobiotic detoxification. 相似文献
73.
Stransky N Egloff AM Tward AD Kostic AD Cibulskis K Sivachenko A Kryukov GV Lawrence MS Sougnez C McKenna A Shefler E Ramos AH Stojanov P Carter SL Voet D Cortés ML Auclair D Berger MF Saksena G Guiducci C Onofrio RC Parkin M Romkes M Weissfeld JL Seethala RR Wang L Rangel-Escareño C Fernandez-Lopez JC Hidalgo-Miranda A Melendez-Zajgla J Winckler W Ardlie K Gabriel SB Meyerson M Lander ES Getz G Golub TR Garraway LA Grandis JR 《Science (New York, N.Y.)》2011,333(6046):1157-1160
Head and neck squamous cell carcinoma (HNSCC) is a common, morbid, and frequently lethal malignancy. To uncover its mutational spectrum, we analyzed whole-exome sequencing data from 74 tumor-normal pairs. The majority exhibited a mutational profile consistent with tobacco exposure; human papillomavirus was detectable by sequencing DNA from infected tumors. In addition to identifying previously known HNSCC genes (TP53, CDKN2A, PTEN, PIK3CA, and HRAS), our analysis revealed many genes not previously implicated in this malignancy. At least 30% of cases harbored mutations in genes that regulate squamous differentiation (for example, NOTCH1, IRF6, and TP63), implicating its dysregulation as a major driver of HNSCC carcinogenesis. More generally, the results indicate the ability of large-scale sequencing to reveal fundamental tumorigenic mechanisms. 相似文献
74.
Ulrich Meyer Kristin Weigel Friedrich Schne Matthias Leiterer Gerhard Flachowsky 《Livestock Science》2008,115(2-3):219-225
The aim of the present study was to assess the influence of different levels of iodine supplementation on animal growth and the iodine content of food from beef cattle. In a dose–response experiment with 34 growing fattening bulls of the “German Holstein” breed, in the range from 223 to 550 kg body weight, three iodine dosages were tested. The animals were fed a corn silage/concentrate ration. Iodine concentration in the diet amounted to 0.79 (Group 1), 3.52 (Group 2) and 8.31(Group 3) mg I per kg dry matter (DM). After slaughtering, I was determined in blood, serum, plasma, thyroid, liver, kidneys and meat (M. longissimus dorsi, M. glutaeus medius) by ICP-MS. I-supplementation did not significantly influence DM intake, daily weight gain (1453 (1), 1419 (2) and 1343 (3) g; p > 0.05) or slaughtering performance, but the weight of the thyroid gland increased significantly with the highest I dosage (32 (1), 26 (2) and 42 (3) g animal− 1, p < 0.05). I-supplementation significantly increased I-concentration in muscle, liver, kidney and thyroid gland (p < 0.05). The contribution of beef food to I-intake of humans is relatively low, therefore there is no need to reduce the EU-upper limit (10 mg kg− 1 feed) for growing fattening cattle from the view of consumer safety. In view of animal health and performance more dose–response studies seem to be necessary. 相似文献
75.
Rauch A Thiel CT Schindler D Wick U Crow YJ Ekici AB van Essen AJ Goecke TO Al-Gazali L Chrzanowska KH Zweier C Brunner HG Becker K Curry CJ Dallapiccola B Devriendt K Dörfler A Kinning E Megarbane A Meinecke P Semple RK Spranger S Toutain A Trembath RC Voss E Wilson L Hennekam R de Zegher F Dörr HG Reis A 《Science (New York, N.Y.)》2008,319(5864):816-819
Fundamental processes influencing human growth can be revealed by studying extreme short stature. Using genetic linkage analysis, we find that biallelic loss-of-function mutations in the centrosomal pericentrin (PCNT) gene on chromosome 21q22.3 cause microcephalic osteodysplastic primordial dwarfism type II (MOPD II) in 25 patients. Adults with this rare inherited condition have an average height of 100 centimeters and a brain size comparable to that of a 3-month-old baby, but are of near-normal intelligence. Absence of PCNT results in disorganized mitotic spindles and missegregation of chromosomes. Mutations in related genes are known to cause primary microcephaly (MCPH1, CDK5RAP2, ASPM, and CENPJ). 相似文献
76.
Rainer Froese Nazli Demirel Gianpaolo Coro Kristin M Kleisner Henning Winker 《Fish and Fisheries》2017,18(3):506-526
This study presents a Monte Carlo method (CMSY) for estimating fisheries reference points from catch, resilience and qualitative stock status information on data‐limited stocks. It also presents a Bayesian state‐space implementation of the Schaefer production model (BSM), fitted to catch and biomass or catch‐per‐unit‐of‐effort (CPUE) data. Special emphasis was given to derive informative priors for productivity, unexploited stock size, catchability and biomass from population dynamics theory. Both models gave good predictions of the maximum intrinsic rate of population increase r, unexploited stock size k and maximum sustainable yield MSY when validated against simulated data with known parameter values. CMSY provided, in addition, reasonable predictions of relative biomass and exploitation rate. Both models were evaluated against 128 real stocks, where estimates of biomass were available from full stock assessments. BSM estimates of r, k and MSY were used as benchmarks for the respective CMSY estimates and were not significantly different in 76% of the stocks. A similar test against 28 data‐limited stocks, where CPUE instead of biomass was available, showed that BSM and CMSY estimates of r, k and MSY were not significantly different in 89% of the stocks. Both CMSY and BSM combine the production model with a simple stock–recruitment model, accounting for reduced recruitment at severely depleted stock sizes. 相似文献
77.
MacDonald KA Kittleson MD Munro C Kass P 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2003,17(2):172-177
Plasma brain natriuretic peptide concentration ([BNP]) is high in humans with cardiac disease and is further increased with congestive heart failure (CHF). The hypotheses of this study were that dogs with moderate to severe mitral regurgitation due to myxomatous mitral valve disease (MVD) would have increased plasma [BNP] compared to normal dogs, that plasma [BNP] would be higher in dogs with CHP, and that plasma [BNP] would predict premature death from cardiovascular disease. The study population consisted of 34 dogs: 9 normal dogs and 25 dogs with MVD. Patients were divided into 4 groups: group 1-10 dogs with moderate to severe MVD and no radiographic evidence of CHF; group II--6 dogs with severe MVD and mild CHF; group III--7 dogs with severe MVD and moderate CHF; and group IV--2 dogs with severe MVD and severe CHF. Diagnostic tests included thoracic radiographs, an echocardiogram, a serum chemistry profile, and the measurement of plasma [BNP] by a canine-specific radioimmunoassay. There was a significant positive correlation between the plasma [BNP] and heart disease/failure groups (P = .0036). Plasma [BNP] increased with progressively increasing severity of MVD and CHE Group I dogs had higher plasma [BNP] than did control dogs (P < .0001), and plasma [BNP] was higher in dogs with CHF (groups II-IV versus group I; P = .012). Plasma [BNP] was also weakly positively correlated with left atrial size (r = 0.43, P = .04). For every 10-pg/mL increase in plasma [BNP], the mortality rate over 4 months' time increased approximately 44%. 相似文献
78.
Schafgans KE Armstrong PJ Kramek B Ober CP 《Journal of Feline Medicine and Surgery》2012,14(10):759-763
A 7-month-old female spayed domestic shorthair cat was presented for investigation of stertor, open mouth breathing without apparent distress, and chronic bilateral nasal discharge that was unresponsive to antibiotics. Complete bilateral bony choanal atresia was diagnosed with computed tomography and nasopharyngoscopy. Choanal atresia is an uncommon congenital condition where the choana (nasal passage into the nasopharynx) is blocked by abnormal bone or soft tissue uni- or bilaterally. The cat's clinical signs improved dramatically immediately after trans-palatal surgical correction. Post-surgical complications included the development of nasopharyngeal scar tissue and subsequent stenosis, persistent right-sided nasal discharge, and permanent damage to the right eye (blindness and cataract formation). Nasopharyngeal stenosis was managed with repeated balloon dilatations and temporary stenting, and the owner reported an excellent quality of life at 8-month follow-up. Bilateral bony choanal atresia has not been previously reported in cats. Uni- or bilateral choanal atresia should be considered in young cats presenting with refractory stertor, chronic nasal discharge, and/or open mouth breathing. 相似文献
79.
Kevin T Fitzgerald Kristin L Newquist 《Veterinary Clinics of North America: Exotic Animal Practice》2008,11(2):327-57, vii
Reptiles are increasingly being kept as pets in American households. The basic principles of emergency medicine are the same for all species, but reptilian species present special diagnostic challenges to veterinary clinicians when they become ill. Reptiles in captivity can become accidentally poisoned in a variety of ways. Veterinarians treating small animal emergencies must make an effort to familiarize themselves with the large body of literature and resources that are developing regarding both nontraditional exotic companion species and advances in toxicology. 相似文献
80.
Elliott R. Jacobson Kristin H. Berry Dennis E. Brooks John F. Roberts 《Veterinary ophthalmology》2023,26(4):361-366
A wild Agassiz's desert tortoise, Gopherus agassizii, with bilateral eyelid reduction and plaques of tissue covering the superior surface of both corneas was examined in the field and subsequently submitted to the University of Florida for diagnostics. Polymerase chain reaction (PCR), from a swab of both corneas, was positive for Mycoplasma agassizii. Two months later, the tortoise was euthanatized and necropsied. There was increased bulbar exposure associated with dermal excoriation of periocular scales in both superior and inferior palpebra resulting in an increased palpebral fissure opening. Concurrently, there was bilateral conjunctivitis of the nictitating membranes and squamous metaplasia of the bulbar conjunctiva. Using PCR, Mycoplasma testudineum, another pathogen of tortoises, was identified in both nasal cavities, and the upper respiratory tract histopathological findings were consistent with those described for M. testudineum in Agassiz's desert tortoises. Although eye disease has been reported in desert and gopher (Gopherus polyphemus) tortoises with mycoplasmosis, widespread loss of palpebral tissue, conjunctivitis of the nictitans, and squamous metaplasia of the bulbar conjunctiva have not been reported in tortoises. 相似文献