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排序方式: 共有175条查询结果,搜索用时 31 毫秒
61.
MC McCarthy MJ Travers A Kovacs W Chen SE Novick CA Gottlieb P Thaddeus 《Science (New York, N.Y.)》1997,275(5299):518-520
Two cumulene carbenes, H2C5 and H2C6, were detected in a supersonic molecular beam by Fourier transform microwave spectroscopy. Their rotational and leading centrifugal distortion constants were determined with high accuracy, such that the entire radio spectrum can now be calculated. Like the known carbenes H2C3 and H2C4, both molecules have singlet electronic ground states and linear carbon-chain backbones. They can be produced in sufficiently high concentrations in the laboratory that their electronic spectra, expected to lie in the visible, should be readily detectable by laser spectroscopy. The microwave spectra of other, more exotic isomers may be detectable as well. 相似文献
62.
MICHELE P. LAURENSON ALLISON L. ZWINGENBERGER DEREK D. CISSELL LYNELLE R. JOHNSON MATIE J. McPETERS MATHIEU P. SPRIET SANDRA L. TAYLOR RACHEL E. POLLARD 《Veterinary radiology & ultrasound》2011,52(4):357-361
The pharynx is anatomically complex and evaluation can be difficult even with cross‐sectional imaging. Eight animals had computed tomography (CT) studies of the head performed with the mouth open and closed. The studies were anonymized and evaluated by four radiologists for visibility of six anatomic regions (dorsal wall of nasopharynx, lumen of nasopharynx, dorsal margin of the soft palate, ventral margin of the soft palate, oropharynx, and laryngopharynx) and for certainty of a normal or abnormal diagnosis of four different anatomic regions (nasopharynx, soft palate, oropharynx, and laryngopharynx). Mean visual scores differed significantly between mouth positions and were improved when the mouth was open. The ability of radiologists to classify anatomic regions as normal or abnormal vs. unsure also varied between mouth positions, and there was greater uncertainty when the mouth was closed. In addition, estimated volume of the air‐filled nasopharynx differed significantly as a function of mouth position and was greater when the mouth was open (mean=1.187 cm3, SE=0.177) vs. closed (mean=0.584 cm3, SE=0.116). Computed tomographic evaluation of the pharynx can be improved with the mouth open. 相似文献
63.
64.
Triplets in red deer (Cervus elaphus) 总被引:1,自引:0,他引:1
65.
Fresh, mature, ungrazed Tribulus terrestris plant material was subjected to a standard alkaloid extraction procedure. The extract was fractionated by thin layer chromatography (TLC) and high performance liquid chromatography (HPLC). Two major alkaloid fractions were demonstrated. These fractions were identified by means of TLC, ultraviolet spectrofluorimetry (UVS) and HPLC, as the beta-carboline indoleamines harmane and norharmane. The extractable alkaloid content was determined to be 44 mg/kg dry matter. Synthetic harmane and norharmane were administered subcutaneously to sheep at a dose rate of 54 mg/kg. Both compounds caused similar nervous effects. The main effect observed was limb paresis, which in some sheep was body side blased. The clinical signs observed in the experimental sheep were consistent with those described for naturally occurring cases of Tribulus terrestris staggers. It was proposed that harmane and norharmane accumulate in tryptamine-associated neurones of the central nervous system, during months of tribulus ingestion, and gradually interact irreversibly with a specific neuronal gene DNA sequence. 相似文献
66.
67.
Abstract AIMS: To ascertain the levels of awareness of legislation governing the welfare of cats, and provision of basic care, including vaccination, by cat-owners within two locations in New Zealand. To assess the ability of respondents to differentiate between the terms ‘stray’ and ‘feral’. METHODS: A face-to-face questionnaire, consisting of 12 questions in three sections, was distributed by volunteers within Auckland (n=255) and Kaitaia (n=99) to gather information pertinent to the study's aims. Section 1 covered respondents’ personal details; Section 2, ownership and care of cats, including whether or not the cats were vaccinated against feline immunodeficiency virus (FIV) and feline leukaemia virus (FeLV); and Section 3, awareness of legislation and differences between the terms ‘stray’ and ‘feral’. RESULTS: Overall, fewer than half of respondents were aware of the animal welfare legislation within New Zealand or the semantic differences between the terms ‘stray’ and ‘feral’ as they appear in the dictionary. Respondents ≥41 years old, and individuals employed in the animal-related sector, were significantly more likely to be aware of the legislation and make the correct distinction between the terms compared with those aged ≤40, and those working in a non-animal-related profession. A significantly greater percentage of cat-owners (42%) provided care for cats they did not own compared with non-owners (26%). Results also indicated a large majority of cat-owners may consider standard annual vaccinations to include vaccination against FIV and FeLV. CONCLUSION: Dissemination of information about animal welfare legislation is important for the care of cats within New Zealand, and the definitions of the terms ‘stray’ and ‘feral’ need to be more clearly stated in order to prevent confusion. This is especially important when cats may be controlled using lethal measures under different legislative precedents that are not necessarily consistent with one another. CLINICAL RELEVANCE: Veterinary clinics may act as a primary source for the dissemination of information about relevant welfare acts as well as preventative health care, thus improving the welfare of cats. Cat-owners need to be better educated about the diseases covered by annual vaccination. 相似文献
68.
CHRISTOPHER R. BYRON DVM MS Diplomate ACVS BRITANY M. BENSON DVM WILLIAM M. KARLIN DVM ALLISON A. STEWART DVM MS Diplomate ACVS 《Veterinary surgery : VS》2010,39(2):239-243
Objective— To report the use of a proximolateral endoscopic portal with a distolateral instrument portal for carpal retinaculum release in a horse clinically affected with carpal canal syndrome. Study Design— Clinical report. Animals— A 4‐year‐old Thoroughbred female. Methods— Carpal canal syndrome secondary to traumatic suppurative tenosynovitis was treated by accessory carpal bone debridement and carpal retinaculum release using a tenoscopic approach to the carpal flexor synovial sheath through a proximolateral endoscope portal and a distolateral instrument portal. Results— Resolution of carpal sheath effusion and lameness occurred allowing racing 14 months later. Use of a distolateral instrument portal was not associated with complications or iatrogenic damage to neurovascular structures and reduced endoscope and instrument interference and offered easier access to the distal aspect of the carpal sheath. Conclusions— Carpal retinaculum release may be safely accomplished with a distolateral instrument portal when access to the distal aspect of the carpal sheath is needed. Clinical Relevance— The distolateral instrument portal described may be a useful alternative to a proximolateral portal when distal carpal sheath instrument access is necessary or advantageous. 相似文献
69.
R Manjarin JC Dominguez MJ Castro B Alegre MA Driancourt RN Kirkwood 《Reproduction in domestic animals》2010,45(3):555-557
Gilt oestrus and ovulation responses to injection of a combination of equine chorionic gonadotrophin (eCG) and human chorionic gonadotrophin (hCG) (PG600) can be unpredictable, possibly reflecting inadequate circulating LH activity. The objective of this study was to determine the effect of PG600 followed by supplemental hCG on gilt ovarian responses. In experiment 1, 212 Hypor gilts (160 day of age) housed on two farms in Spain received intramuscular (i.m.) injections of PG600 (n = 47), or PG600 with an additional 200 IU hCG injected either concurrently (hCG‐0; n = 39), or at 24 h (hCG‐24; n = 41) or 48 h (hCG‐48; n = 45) after PG600. A further 40 gilts served as non‐injected controls. Ovulation responses were determined on the basis of initial blood progesterone concentrations being <1 ng/ml and achieving >5 ng / ml 10 d after the PG600 injection. The incidence of ovulating gilts having progesterone concentrations >30 ng/ml were recorded. During the study period, 10% of control gilts ovulated whereas 85–100% of hormone‐treated gilts ovulated. There were no significant differences among hormone groups for proportions of gilts ovulating. The proportions of gilts having circulating progesterone concentrations >30 ng/ml were increased (p ≤ 0.02) in all hCG treated groups compared with the PG600 group. In experiment 2, a total of 76 Hypor gilts at either 150 or 200 days of age were injected with PG600 (n = 18), 400 IU eCG followed by 200 IU hCG 24 h later (n = 20), PG600 followed by 100 IU hCG 24 h later (n = 17), or 400 IU eCG followed by 300 IU hCG 24 h later (n = 21). Blood samples were obtained 10 days later for progesterone assay. There were no effects of treatment or age on incidence of ovulation, but fewer 150‐day‐old gilts treated with PG600 or 400 IU eCG followed by 200 IU hCG had progesterone concentrations >30 ng / ml. We conclude that hCG treatment subsequent to PG600 treatment will generate a higher circulating progesterone concentration, although the effect is not evident in older, presumably peripubertal, gilts. The mechanism involved and implications for fertility remain to be determined. 相似文献
70.
M Russo D Vecchio G Neglia C Pacelli A Prandi B Gasparrini L Zicarelli MJ D’Occhio G Campanile 《Reproduction in domestic animals》2010,45(6):988-991
The aim in this study was to investigate corpus luteum function and embryonic loss in buffaloes mated by artificial inseminations (AI) during the transitional period from breeding to non‐breeding season. The study was carried out using 288 multiparous Italian Mediterranean Buffalo cows at 110 ± 4 days in milk. The buffaloes were mated by AI after synchronization of ovulation by the Ovsynch‐TAI protocol 25 days after AI buffaloes underwent trans‐rectal ultrasonography to assess embryonic development. Pregnancy diagnosis was confirmed on Days 45 and 70 after AI by rectal palpation. Buffaloes pregnant on Day 25 but not on Day 45 were considered to have undergone late embryonic mortality (LEM), whilst buffaloes pregnant on Day 45 but not on Day 70 were considered to have undergone foetal mortality (FM). Corpus luteum size and blood flow were determined by real‐time B‐mode/colour‐Doppler on day 10 after AI in 122 buffaloes. The resistive index (RI) and pulsatility index (PI) were recorded at the time. Milk samples were collected on Days 10, 20 and 25 after AI in all inseminated buffaloes for the assay of whey P4 concentrations. Data were analysed by anova . Pregnancy rate on Day 25 after AI was 48.6% (140/288) and declined to 35.4% (102/288) and 30.6% (88/288) by Day 45 and Day 70 respectively. The incidences of LEM and FM were respectively 27.1% (38/140) and 13.7% (14/102). Pregnant buffaloes had greater (p < 0.01) whey concentrations of P4 from Day 20 onwards than buffaloes which showed LEM, whilst P4 in buffaloes that showed FM did not differ from the other two groups on Day 10 and Day 20. Corpus luteum blood flow on Day 10 after AI showed higher RI (p < 0.05) and PI (p = 0.07) values in buffaloes that subsequently were not pregnant on Day 25 compared with pregnant buffaloes. Buffaloes that were not pregnant on Day 45 also had a higher (p = 0.02) RI value on Day 10 than pregnant buffaloes, whilst PI values on Day 10 did not differ for the two groups of buffaloes. It was concluded that blood flow to the corpus luteum on Day 10 after AI influences corpus luteum function as judged by P4 secretion and also embryonic development and attachment in buffaloes. 相似文献