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排序方式: 共有128条查询结果,搜索用时 15 毫秒
1.
Antoine LF Gady Freddy WK Hermans Marion HBJ Van de Wal Eibertus N van Loo Richard GF Visser Christian WB Bachem 《Plant methods》2009,5(1):13-14
Background
The establishment of mutant populations together with the strategies for targeted mutation detection has been applied successfully to a large number of organisms including many species in the plant kingdom. Considerable efforts have been invested into research on tomato as a model for berry-fruit plants. With the progress of the tomato sequencing project, reverse genetics becomes an obvious and achievable goal. 相似文献2.
Reproductive Performance and Reconception of Nellore Cows According to Their Pure‐ or Cross‐Bred Calves 下载免费PDF全文
The objective of the present research was to evaluate the effect of a calf's genetic group on the productive and reproductive efficiency of its Nellore dam. Fixed‐time artificial insemination was applied to 800 cows using semen extracted from Nellore, Simmental and Angus Red bulls. Four hundred eleven cows calved, producing 119 Nellore, 103 ½Simmental–½Nellore and 189 ½Nellore–½Angus Red calves. The second mating period, which paired Nellore cows with Simmental bulls, was initiated 10 days after parturitions began and lasted for 5 months. Based on the two successive parturitions, the cumulative parturition rate for calving periods of 3, 4 and 5 months was calculated. Although no significant difference was observed for birth weight among the genetic groups, cross‐bred calves weighed, on average, 10% more than did pure‐bred calves at the age of 205 days. Nellore dams experienced a gestation period that was 7 days longer than did the cross‐bred dams, and the former showed a higher parturition rate at 90 and 120 days of the calving season, but not at 150 days (calving rates of 80.6, 76.4 and 76.2% for mothers of Nellore, ½Nellore–½Angus Red and ½Nellore–½Simmental, respectively, p > 0.05). At 90 and 120 days, Nellore dams produced more kg of calf per mated dam. In conclusion, in a short breeding season, Nellore dams nursing pure‐bred Nellore calves were found to have a higher biological efficiency compared with Nellore dams nursing cross‐bred calves. 相似文献
3.
Nielsen C Stover SM Schulz KS Hubbard M Hawkins DA 《American journal of veterinary research》2003,64(5):609-617
OBJECTIVE: To calculate normative joint angle, intersegmental forces, moment of force, and mechanical power at elbow, antebrachiocarpal, and metacarpophalangeal joints of dogs at a walk. ANIMALS: 6 clinically normal mixed-breed dogs. PROCEDURE: Kinetic data were collected via a force platform, and kinematic data were collected from forelimbs by use of 3-dimensional videography. Length, location of the center of mass, total mass, and mass moment of inertia about the center of mass were determined for each of 4 segments of the forelimb. Kinematic data and inertial properties were combined with vertical and craniocaudal ground reaction forces to calculate sagittal plane forces and moments across joints of interest throughout stance phase. Mechanical power was calculated as the product of net joint moment and the angular velocity. Joint angles were calculated directly from kinematic data. RESULTS: All joint intersegmental forces were similar to ground reaction forces, with a decrease in magnitude the more proximal the location of each joint. Flexor moments were observed at metacarpophalangeal and antebrachiocarpal joints, and extensor moments were observed at elbow and shoulder joints, which provided a net extensor support moment for the forelimb. Typical profiles of work existed for each joint. CONCLUSIONS AND CLINICAL RELEVANCE: For clinically normal dogs of a similar size at a walk, inverse dynamic calculation of intersegmental forces, moments of force, and mechanical power for forelimb joints yielded values of consistent patterns and magnitudes. These values may be used for comparison in evaluations of gait in other studies and in treatment of dogs with forelimb musculoskeletal disease. 相似文献
4.
Prostatic adenocarcinoma in a cat 总被引:2,自引:0,他引:2
B S Hubbard J C Vulgamott W D Liska 《Journal of the American Veterinary Medical Association》1990,197(11):1493-1494
Prostatic adenocarcinoma was diagnosed in an 11-year-old neutered cat. Clinical signs of the disease included hematuria and a mass in the caudal portion of the abdomen. Prostatectomy was performed. Doxorubicin was administered IV at a dosage of 30 mg/m2 of body surface, followed by cyclophosphamide (300 mg/m2, IV). After 4 treatments, low urine specific gravity and proteinuria developed, and treatment was discontinued. The cat was euthanatized 10 months after surgery because of recurrence of the neoplasm. Necropsy revealed metastasis to the lungs and pancreas. 相似文献
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Hubbard GG 《Science (New York, N.Y.)》1885,5(117):356-360
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An electroimmobilisation device has been developed to facilitate the automated shearing of sheep, but there is little information on its effects on the body. We have studied its effects on the cardiovascular system and on intermediary metabolism in sheep. Electroimmobilisation caused statistically significant increases in mean arterial pressure, heart rate, cardiac output, renal and hepatic and hindquarter glucose and lactate flux, organ and whole body oxygen flux, hindquarter blood flow and core temperature and decreases in arterial and posterior vena cava blood pH, renal and hepatic blood flow and PaCO2. Notably, no change occurred in PaO2. The metabolic changes demonstrated the capacity of sheep to respond to the increased muscular and cardiovascular work induced by electroimmobilisation. Pulmonary function was not compromised during electroimmobilisation as judged from blood gas changes, and the acid/base changes were rapidly reversed after electroimmobilisation. The recovery to control conditions for all perturbations generally took no longer than 30 min, consistent with a rapid and physiologically adequate reversal by the animal's homeostatic mechanisms. 相似文献
10.
Nathan?C.?HealeyEmail author Ayse?Irmak Timothy?J.?Arkebauer David?P.?Billesbach John?D.?Lenters Kenneth?G.?Hubbard Richard?G.?Allen Jeppe?Kjaersgaard 《Irrigation and Drainage Systems》2011,25(3):151-178
Water consumed through evapotranspiration (ET) impacts local and regional hydrologic regimes on various spatial and temporal
scales. Estimating ET in the Great Plains is a prerequisite for effective regional water resource management of the Ogallala
(High Plains) Aquifer, which supplies vital water resources in the form of irrigation for extensive agricultural production.
The Sand Hills region of Nebraska is one of the largest grass-stabilized eolian (windblown) sand dune formations in the world,
with an area of roughly 50,000–60,000 km2 that supports a system of five major land cover types: (1) lakes, (2) wetlands (with lakes, ~5%), (3) subirrigated meadows
(water table is within ~1 m of surface; ~10%), (4) dry valleys (water table is 1–10 m below surface; ~20%), and (5) upland
dunes (water table is more than 10 m below surface; ~65%). Fully understanding the hydrologic regime of these different ecosystems
is a fundamental challenge in regional water resource assessment. The surface energy and water balances were analyzed using
Bowen Ratio Energy Balance Systems (BREBS) at three locations: (1) a meadow, (2) a valley, and (3) an upland dune. Measurement
of the energy budget by BREBS, in concert with Landsat remote sensing image processing for 2004 reveals strong spatial gradients
between sites in latent heat flux that are associated with undulating topographic relief. We find that daily estimates of
ET from BREBS measurements and remote sensing agree well, with an uncertainty within 1 mm, which is encouraging when applying
remote sensing results across such a broad spatial scale and undulating topography. 相似文献