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341.
342.
Primate-specific segmental duplications are considered important in human disease and evolution. The inability to distinguish between allelic and duplication sequence overlap has hampered their characterization as well as assembly and annotation of our genome. We developed a method whereby each public sequence is analyzed at the clone level for overrepresentation within a whole-genome shotgun sequence. This test has the ability to detect duplications larger than 15 kilobases irrespective of copy number, location, or high sequence similarity. We mapped 169 large regions flanked by highly similar duplications. Twenty-four of these hot spots of genomic instability have been associated with genetic disease. Our analysis indicates a highly nonrandom chromosomal and genic distribution of recent segmental duplications, with a likely role in expanding protein diversity.  相似文献   
343.
Carcass characteristics, meat quality traits, and sensory attributes were evaluated in late-finishing barrows and gilts, weighing between 100 to 130 kg of BW, fed 0, 5, or 7.4 mg/kg of ractopamine hydrochloride (RAC) for the final 21 to 28 d before slaughter. Carcass data were collected from carcasses from barrows and gilts (n = 168), and all primal cuts from the right sides of these carcasses were fabricated to calculate primal yields as a percentage of the HCW. Subjective (National Pork Producers Council and Japanese) color, firmness, and marbling scores were determined on the LM of each loin and the semimembranosus muscle (SM) of the ham, whereas the moisture, extractable lipid, Warner-Bratzler shear force (WBSF), and trained sensory evaluations (juiciness, tenderness, and pork flavor) were measured on the LM samples only. Gilts produced heavier (P < 0.05) HCW than barrows, whereas feeding RAC increased (P < 0.05) HCW over pigs fed diets devoid of RAC. Carcasses from gilts also had greater (P < 0.02) primal cut and lean cut (P < 0.01) yields than barrows, and dietary inclusion of 5 mg/kg of RAC increased (P < 0.05) total boneless cut and lean cut yields when compared with carcass from pigs fed 0 or 7.4 mg/kg of RAC. Warner-Bratzler shear forces values were greater (P < 0.05) in the LM of gilts than barrows, but only juiciness scores were greater (P < 0.03) in LM chops from barrows than gilts. The LM from barrows had greater intramuscular lipid (P < 0.001) than the LM from gilts, and even though the LM from pigs fed 5 mg/kg of RAC had greater (P < 0.04) WBSF values than the LM from pigs fed 0 or 7.4 mg/kg of RAC, including RAC in the late-finishing diets for 21 or 28 d did not affect sensory panel rating or percentages of moisture and intramuscular lipid. In summary, addition of RAC in the late-finishing diet improved carcass and primal cut yields when it was fed at 5 and 7.4 mg/kg without altering pork quality traits regardless of whether RAC was fed for 21 or 28 d.  相似文献   
344.
The Hematologic values of 19 equine fetuses between 202 and 238 days gestation were compared with those of their dams. The red blood cell (RBC) count, hemoglobin concentration, hematocrit, and mean corpuscular hemoglobin concentration were significantly lower in fetal blood, while the mean corpuscular volume, mean corpuscular hemoglobin, and red cell distribution width were significantly higher. Mares had a significantly higher nucleated blood cell count than fetuses, and all nucleated cells were leukocytes (WBC). Most WBC in mare blood were segmented neutrophils and lymphocytes. In contrast, over one-half of the nucleated cells in fetal blood were nucleated RBC, and the majority of WBC in fetal blood were lymphocytes. Mares also had significantly higher plasma protein and fibrinogen concentrations than their fetuses. Mild macrocytosis and mild polychromasia were observed in most fetal blood samples, but not in blood samples from mares. All fetal blood contained reticulocytes, and most samples contained Heinz bodies and Howell-Jolly bodies. The results of this study will contribute to the development of hematologic reference values that may be useful in equine fetal research and, possibly, in the diagnosis of equine fetal disease.  相似文献   
345.
This article is the first to describe the clinical picture and potential human health impact of laboratory-confirmed rabies infection in a pet Vietnamese pot-bellied pig in Maryland. Although cases of confirmed rabies infection have been infrequently reported in pet or agricultural during the past 10 years in the United States, exposure to rabies-positive animals remains a public health concern particularly for veterinarians, pet owners and other animal caretakers. It is important that individuals who are in a high-risk rabies exposure group remain vigilant to this potential public health threat in all mammal species.  相似文献   
346.
Eighteen Holstein dairy cows ranging in body weight from 500–700 kg and with an average milk yield of 37 ± 6 kg/day were used to investigate the depletion of florfenicol (FFL) in milk and plasma of dairy cows. Three groups of six were administered FFL: Group A, intramammary (IMM) infusion of ~2.5 mg FFL/kg BW at three consecutive milking intervals (total amount of ~7.5 mg/kg BW); Group B, one IMM infusion (20 mg/kg BW) into one quarter and Group C, one subcutaneous (SC) treatment (40 mg/kg BW). IMM infusions were into the right front quarter. Cows were milked daily at 06:00 and 18:00 h. The highest concentrations (Cmax) and time to Cmax (Tmax) were: 1.6 ± 2.2 μg·FFL/mL milk at 22 h (Group A), 5.5 ± 3.6 μg·FFL/mL milk at 12 h (Group B), and 1.7 ± 0.4 μg·FFL/mL milk at 12 h (Group C). The half‐lives (t1/2) were ~19, 5.5, and 60 h, for Groups A, B, and C, respectively. FFL was below the limit of detection (LOD) by 60 h in three Group B cows, but above the LOD at 72, 84, and 120 h in three cows. FFL was above the LOD in milk from Group C's cows for 432–588 h. Plasma values followed the same trends as milk. The results demonstrate that IMM‐infused FFL is bioavailable and below the LOD within 72–120 h. The concentration of FFL was detectable in both plasma and milk over the course of 2–3 weeks after SC administration. The absence of residue depletion data presents problems in determining safe levels of FFL residues in milk and edible tissues. The data presented here must not be construed as approval for extra‐label use in food animals.  相似文献   
347.
A 2-yr study was conducted to determine the effects of three weaning management systems on cow and steer performance. Cow-calf pairs were randomly assigned to one of three treatments, in which the steer calves were 1) early-weaned (yr 1, 177 +/- 9 d; yr 2, 158 +/- 21 d of age) and placed on a finishing diet (EW), 2) supplemented with grain for 55 d on pasture (yr 1, 177 to 231 d; yr 2, 158 to 213 d of age) while nursing their dams and then placed on a finishing diet (NWC), and 3) on pasture for 55 d while nursing their dams (yr 1, 177 to 231 d; yr 2, 158 to 213 d of age) and then placed on a finishing diet (NW). In yr 2, potential breed differences were evaluated using steers of three breed types: 1) Angus x Hereford (BRI); 2) Angus x Simmental (CON); and 3) Angus x Wagyu (WAG). In yr 1, EW steers gained 100% faster (P = .0001) than the average of NWC and NW steers, and NWC steers gained 32% faster (P = .02) than NW steers before weaning. In the feedlot, EW steers had lower intakes (7.70 vs 8.16 kg/d, P = .008) and better feed conversions (.170 vs .153, P = .002) than the average of NWC and NW steers. Marbling score was improved for EW steers compared with the average of NWC and NW steers (P = .003). In yr 2, EW steers had higher gains (P = .0006) during the entire study than the average of NWC and NW steers, and NWC steers had higher gains (P = .003) than NW steers. The EW steers had lower intakes (7.29 vs 7.68 kg/d, P = .0008) and better feed conversions (.160 vs .141, P = .0001) than the average of NWC and NW steers. The CON steers were heavier at slaughter than BRI steers (P = .01), and BRI steers were heavier than WAG steers (P =.0004). Early weaning improved the percentage of steers grading Average Choice or higher by 40%. The percentage of BRI steers grading Choice or greater was 21% higher and percentage of steers grading Average Choice or greater was 33% higher than CON. Cows with EW steers had higher ADG than cows with NW steers (.38 vs -.17 kg/d, P = .0001) before weaning. Cows with EW steers gained in body condition score (.23 vs .00, P = .04), and cows with NW steers did not change. Early weaning improved feed efficiency and quality grades of beef steers.  相似文献   
348.
A 2-yr study was conducted to evaluate 1) steers fed ad libitum high concentrate after weaning (CONC), or 2) steers grown on pasture for 82 d, followed by high-concentrate finishing (PAST), on the performance and carcass traits of 74 early-weaned (117 d of age) steers. Potential breed differences were evaluated using crossbred steers of three types: 1) 3/4 Angus x 1/4 Simmental (BRI), 2) 3/4 Simmental x 1/4 Angus (CON), and 3) 1/2 Wagyu x 1/4 Angus x 1/4 Simmental (WAG). Steers were randomly assigned within breed to the two treatments. There was no interactions (P > .10), so the data were pooled over years. The CONC steers had an ADG that was .17 kg/d higher (P = .0001), intake 1.09 kg/d lower (P = .0001), and gain:feed ratio .013 unit better (.190 vs .177, P = .008) than PAST steers overall. Growing treatment did not affect total concentrate consumed (P = .97). The BRI steers required 31 d less than did CON steers (P = .008), and 23 d less than WAG steers (P = .05) when fed to a constant fat end point (1.1 cm). The BRI steers exhibited an ADG .16 kg/d higher (P = .0003), tended (P = .07) to have an ADG intake .49 kg/d higher, and exhibited gain:feed .01 unit better (.189 vs 180) than WAG steers. When compared with CON steers, BRI steers consumed 310 kg less total concentrate (P = .0003). No differences (P > .38) were observed between growing treatments for carcass characteristics or sensory attributes except that CONC steers tended (P = .11) to improve percentage of steers grading Average Choice or higher by 47% over PAST steers. The WAG steers had a 76-unit higher marbling score (1,000 = Small00, 1,100 = Modest00) (P = .006) than BRI steers, resulting in 19% more (P = .09) steers grading > or = Choice and 82% more (P = .03) grading > or = Average Choice. Liver (P = .15) and rumen (P = .01) weights as a percentage of hot carcass weight were reduced for CONC steers. The CONC steers had higher gain, lower intake, better efficiency, reduced liver and rumen weights, and consumed the same amount of total concentrate when compared with PAST steers. The BRI steers had less finishing days and lower daily intake compared with CON steers. The WAG steers had more days finishing, lower gain, lower intake, more undesirable efficiencies, consumed the same amount of total concentrate, and improved quality grades compared with BRI steers.  相似文献   
349.
An experiment was conducted to compare three weaning ages on cow-calf performance and steer carcass traits. Crossbred steers (n = 168; 1/2 Simmental x 1/4 Angus x 1/4 Hereford) were randomly assigned to three treatments with eight pens per treatment: groups were 1) weaned at an average of 90 d of age (90 +/- 13 d) and placed in the feedlot, 2) weaned at an average of 152 d of age (152 +/- 13 d) and placed in the feedlot, and 3) weaned at an average of 215 d of age (215 +/- 13 d) and placed in the feedlot. The number of days steers were finished decreased by 55 and 38 d (linear, P = .0001) as weaning age increased when slaughtered at a constant fat end point (.81 cm). Weaning at an average of 90 and 152 d of age improved overall ADG by .15 and .07 kg/d, respectively, over weaning at an average of 215 d of age (linear, P = .005). Over the entire finishing period, intake increased (linear, P = .0006) and efficiency was poorer (linear, P = .004) as weaning age increased. Owing to differences in finishing days and intake, total concentrate consumed increased (linear, P = .03) as weaning age decreased. No differences (P > .21) were observed for carcass weight, longissimus muscle area, or yield grade. No differences (P > .19) were observed in marbling score or percentage of steers grading greater than or equal to Choice or Average Choice. Cow body condition score improved (linear, P = .0001) as weaning age decreased. Pregnancy rate improved 12 percentage units (linear, P = .15) for cows on the 90-d weaning treatment. In this study, early weaning improved gain and feed efficiency, but it increased total concentrate consumed.  相似文献   
350.
BACKGROUND: Glutamate dehydrogenase (GLDH) is a mitochondrial enzyme with highest activity in periacinar hepatocytes. It is reported to be a sensitive indicator of hepatic injury; however, results of studies regarding tissue specificity are contradictory. OBJECTIVES: The purpose of the study reported here was to examine the effect of 3 factors on serum GLDH activity in dogs: serum storage, anti-inflammatory oral doses of prednisone, and spontaneous hyperadrenocorticism (HAC). METHODS: Stability of enzyme activity was determined by comparing serum samples stored at approximately 20 degrees C, 4 degrees C, and 20 degrees C for 4, 24, 48, and 72 hours, 1 week, and 6 months. To determine whether orally administered prednisone affected GLDH activity, the median difference in serum GLDH activity was compared between 5 untreated control dogs and 8 dogs that had received a tapering oral dose of prednisone. Lastly, GLDH enzyme activity was compared between 17 dogs with HAC and 16 age-matched controls. RESULTS: GLDH activity remained stable for 48 hours, 1 week, and 6 months, in serum stored at approximately 20 degrees C, 4 degrees C, and 20 degrees C, respectively. The median change in GLDH activity was not significantly different between dogs receiving prednisone and controls; however, dogs with HAC had significantly higher values than those of age-matched controls. CONCLUSIONS: Serum samples should be maintained at 4 degrees C if analysis of GLDH activity will be delayed by >48 hours; serum stored at 20 degrees C yields reliable results for up to 6 months. Serum GLDH activity was not increased in most dogs receiving short-term, anti-inflammatory oral doses of prednisone, in contrast to its increased activity in dogs with HAC.  相似文献   
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