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131.
Background: The endocrine diagnosis of primary hyperaldosteronism in cats currently is based on an increased plasma aldosterone to renin ratio, which has several disadvantages for use in veterinary practice. Objectives: To establish a reference range for the urinary aldosterone to creatinine ratio (UACR) and to determine whether oral administration of either sodium chloride or fludrocortisone acetate is effective for use in a suppression test. Animals: Forty‐two healthy cats from an animal shelter and 1 cat with primary hyperaldosteronism from a veterinary teaching hospital. Methods: Morning urine samples for determination of the basal UACR were collected from 42 healthy cats. For the suppression tests, urine samples for the UACR were collected after twice daily oral administration for 4 consecutive days of either sodium chloride, 0.25 g/kg body weight (n = 22) or fludrocortisone acetate, 0.05 mg/kg body weight (n = 15). Results: The median basal UACR was 7.2 × 10?9 (range, 1.8–52.3 × 10?9), with a calculated reference range of <46.5 × 10?9. Administration of sodium chloride resulted in adequate salt loading in 10 of 22 cats, but without significant reduction in the UACR. Administration of fludrocortisone resulted in a significant decrease in the UACR (median, 78%; range, 44–97%; P < .001) in healthy cats. In the cat with an aldosterone‐producing adrenocortical carcinoma, the basal UACR and the UACR after fludrocortisone administration were 32 × 10?9 and 36 × 10?9, respectively. Conclusions and Clinical Importance: Using the UACR for an oral fludrocortisone suppression test may be useful for the diagnosis of primary hyperaldosteronism in cats.  相似文献   
132.
1. Naked oats belong to the same species as 'common oats', Avena sativa, but have a non-lignified husk which readily becomes detached during harvesting. The absence of the indigestible husk can be predicted to give an increased metabolisable energy (ME) content for poultry. 2. Measurements of true metabolisable energy (TME(N)) were performed on 3-week-old broiler chicks (Cobb males), adult cockerels (ISA Brown, greater than one year old) and 7-week-old turkeys (BUT T8 males). The measurements were repeated in 2000, 2001 and 2002, with some measurements on a subset of varieties in 2004. 3. High-oil naked oat lines yielded 12% more energy (TME(N)) than wheat. Naked oats, excluding the experimental high-oil lines, yielded 8.5% more energy than simultaneously assayed wheat samples. 4. In samples from the 2004 harvest, conventional oats gave TME(N) values about 13% lower than those of wheat. 5. The addition of beta-glucanase produced an increase of about 4% in the apparent metabolisable energy (AME) of oats for broiler chickens. This effect was associated with a 70% decrease in the jejunal viscosity of broilers receiving a 500 g/kg naked-oat diet. 6. The oil content of naked oats was about 5 times greater than that of wheat, with the high-oil lines rising to more than 6 times greater. Naked oats had a lower starch content than wheat but not sufficiently lower to negate the energy benefits of the higher oil content. The crude protein (CP) contents of naked oats were similar to those of wheat, with the high-oil varieties tending to be higher in CP also.  相似文献   
133.
Plague is a rare but often fatal zoonosis endemic to the western United States. Previous studies have identified contact with pets as a potential risk factor for infection. We conducted a matched case-control study to better define the risks associated with pets at both the household and individual levels. Using a written questionnaire, we surveyed nine surviving plague patients, 12 household members of these patients, and 30 age- and neighbourhood-matched controls about household and individual exposures. Overall, 79% of households had at least one dog, 59% had at least one cat and 33% used flea control, with no significant differences between case and control households. Four (44%) case households reported having a sick dog versus no (0%) control households [matched odds ratio, (mOR) 18.5, 95% confidence interval (CI) 2.3-infinity], and four (44%) patients reported sleeping in the same bed with a pet dog versus three (10%) controls (mOR 5.7, 95% CI 1.0-31.6). Within case households with multiple members, two (40%) of five patients slept with their dogs versus none (0%) of 12 healthy family members (P=0.13). The exposures to cats were not significant. Sleeping in the same bed as a pet dog remained significantly associated with infection in a multivariate logistic regression model (P=0.046). Our findings suggest that dogs may facilitate the transfer of fleas into the home and that activities with close extended contacts with dogs may increase the risk of plague infection.  相似文献   
134.
Background: When an animal is exposed to a stressor, metabolic rate, energy consumption and utilisation increase primarily through activation of the hypothalamic-pituitary-adrenal(HPA) axis. Changes to partitioning of energy by an animal are likely to influence the efficiency with which it is utilised. Therefore, this study aimed to determine the physiological stress response to an exogenous adrenocorticotropic hormone(ACTH) challenge in beef heifers divergently ranked on phenotypic residual feed intake(RFI).Results: Data were collected on 34 Simmental weaning beef heifers the progeny of a well characterized and divergently bred RFI suckler beef herd. Residual feed intake was determined on each animal during the postweaning stage over a 91-day feed intake measurement period during which they were individually offered adlibitum grass silage and 2 kg of concentrate per head once daily. The 12 highest [0.34 kg DM/d] and 12 lowest[-0.48 kg DM/d] ranking animals on RFI were selected for use in this study. For the physiological stress challenge heifers(mean age 605 ± 13 d; mean BW 518 ± 31.4 kg) were fitted aseptically with indwelling jugular catheters to facilitate intensive blood collection. The response of the adrenal cortex to a standardised dose of ACTH(1.98 IU/kg metabolic BW~(0.75)) was examined. Serial blood samples were analysed for plasma cortisol, ACTH and haematology variables. Heifers differing in RFI did not differ(P = 0.59) in ACTH concentrations. Concentration of ACTH peaked(P 0.001) in both RFI groups at 20 min post-ACTH administration, following which concentration declined to baseline levels by 150 min. Similarly, cortisol systemic profile peaked at 60 min and concentrations remained continuously elevated for 150 min. A RFI × time interaction was detected for cortisol concentrations(P = 0.06) with high RFI heifers had a greater cortisol response than Low RFI from 40 min to 150 min relative to ACTH administration. Cortisol response was positively associated with RFI status(r = 0.32; P 0.01). No effect of RFI was evident for neutrophil, lymphocytes, monocyte, eosinophils and basophil count. Plasma red blood cell number(6.07 vs. 6.23; P = 0.02) and hematocrit percentage(23.2 vs. 24.5; P = 0.02) were greater for low than high RFI animals.Conclusions: Evidence is provided that feed efficiency is associated with HPA axis function and susceptibility to stress, and responsiveness of the HPA axis is likely to contribute to appreciable variation in the efficiency feed utilisation of cattle.  相似文献   
135.
奶牛产犊前后间隔的六周过渡期是一个非常关键的时段。此阶段不好的饲养管理会造成产奶量下降、繁殖效率的低下和增加代谢疾病等一系列问题,这不仅增加每千克牛奶的饲料成本而且也会降低牧场的整体营业收入。对于一个奶牛场而言,为了实现生产利润最大化就必须要求营养师、兽医师和牧场管理者达成共识,紧密配合共同来制定一个可行的饲养管理策略,以便帮助奶牛平稳地渡过产犊前后这个关键时期,以最大限度地发挥出奶牛的生产性能。  相似文献   
136.
137.
An effective live-trap was designed for Cryptomys hottentotus (Bathyergidae) arid Amblysomus hottentotus (Chrysochloridae). Factors involved in the design and adaptability of this trap for use in various field conditions and live capture of other fossorial mammals are discussed.  相似文献   
138.
CASE DESCRIPTION: 8 adult dogs were evaluated for treatment of lethargy and vomiting after ingestion of xylitol, a sugar alcohol used as a sweetener in various products. CLINICAL FINDINGS: In addition to vomiting and lethargy, 5 of the dogs had widespread petechial, ecchymotic, or gastrointestinal tract hemorrhages. Common clinicopathologic findings included moderately to severely high serum activities of liver enzymes, hyperbilirubinemia, hypoglycemia, hyperphosphatemia, prolonged clotting times, and thrombocytopenia. Necropsies were performed on 3 dogs and severe hepatic necrosis was found in 2. In the third dog, histologic examination revealed severe hepatocyte loss or atrophy with lobular collapse. TREATMENT AND OUTCOME: Treatments varied among dogs and included IV administration of fluids; plasma transfusions; and, if indicated, administration of dextrose. Three dogs were euthanatized, 2 dogs died, 2 dogs made a complete recovery, and 1 dog was recovering but was lost to follow-up. CLINICAL RELEVANCE: Although xylitol causes hypoglycemia in dogs, hepatic failure after ingestion has not previously been reported. Because an increasing number of consumer products contain xylitol, clinicians should be aware that ingestion of xylitol can have serious, life-threatening effects.  相似文献   
139.
Diuretic renal scintigraphy is commonly used in human medicine to differentiate obstructive from nonobstructive pyelectasia. In order to determine normal parameters, 99mTc-DTPA renal scintigraphy was performed twice in 20 healthy adult Mongrel dogs. Each dog was injected with either 3.0 mg/kg furosemide or an equivalent volume of saline 4.5 min following injection of the radiopharmaceutical. The following parameters were evaluated: (1) global and individual glomerular filtration rate (GFR); (2) time of peak (TOP) of the time-activity curve (TAC); (3) shape of the TAC; (4) individual kidney excretion half-time (T1/2); (5) proportion of maximum activity measured at end of study (8 min); (6) time of onset; and (7) duration of the effect of the diuretic. Most TAC in the diuretic renography group showed a steep drop in the curve following administration of the diuretic compared with a gradual slope in the saline control group. There was a statistically significant difference in T1/2 between the control renograms (median 10.25 min, range 4.41-18.07 min) and the diuretic renograms (median 4.16 min, range 3.62-5.90 min). There was a statistically significant difference in percentage maximum activity between the control renograms (median 65.25%, range 48.27-93.68%) and the diuretic renograms (median 48.54%, range 35.64-58.76%). Median time of onset of the diuretic effect was 1.10 min (0.20-2.40 min), and median duration was 0.83 min (0.30-2.35 min).  相似文献   
140.
A key element in the EU Common Agricultural Policy (CAP) will be a single farm payment system that is linked to compliance with rules on, for instance hygiene standards. However, there are no recommended methods for assessing the hygiene proficiency of pig production farms. The present study was undertaken to develop a method for this purpose. A first implementation was done on pilot scale; with a set of both conventional and organic pig farms (N = 15). Fifty hygiene-related factors were selected, especially with reference to the possible proliferation of enteric pathogens Listeria monocytogenes, Yersinia enterocolitica and Yersinia pseudotuberculosis. The factors were allocated into 8 evaluation categories: (1) general production management, (2) animal density, (3) the outdoor area for pigs, (4) pest and pet animals, (5) general hygiene in the piggery, (6) pen hygiene, (7) feed production hygiene, and (8) feeding hygiene. A farm questionnaire and a supplementary on-site observation form were devised, and one arbitrary scale of hygiene points assigned for each factor. In addition to the mailed questionnaires, one person subsequently visited all the farms, perused the questionnaire with the owners and completed the observation form. The hygiene scores of the farms in each evaluation category were compared both without weighting and with weighting based on expert opinions. The method proved to be feasible and applicable to different types of production.  相似文献   
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