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101.
Thirteen uterine tumors were diagnosed in 13 cats and accounted for 0.29% of all feline neoplasms received during a 9.6-year period. Age at diagnosis ranged from 3 to 16 years; median 9 years. Six were Domestic Shorthair cats, and 7 were purebred cats of 5 different breeds. Eight adenocarcinomas and 1 mixed Müllerian tumor (adenosarcoma) comprised the endometrial tumors. Myometrial tumors included 3 leiomyomas and 1 leiomyosarcoma. One of the adenocarcinomas developed in the uterine stump of an ovariohysterectomized cat; the other cats were sexually intact. Concurrent mammary adenocarcinoma was diagnosed in 1 cat with uterine adenocarcinoma and in another with uterine leiomyoma. Tumors were discovered during elective ovariohysterectomy in 2 cats, but at least 3 others had experienced reproductive problems (infertility or pyometra). Five cats presented for abdominal or pelvic masses. Endometrial adenocarcinomas were positive immunohistochemically for cytokeratins and negative for smooth muscle actin (SMA): 1 of 6 cats was positive for vimentin and 4 of 8 were positive for estrogen receptor-alpha (ER alpha). Adenosarcoma stromal cells were positive for vimentin and ER alpha but negative for cytokeratins and SMA. Smooth muscle tumors were positive for vimentin and SMA and negative for cytokeratins. Leiomyomas, but not the leiomyosarcomas, were positive for ER alpha. Adenocarcinomas in 4 cats had metastasized by the time of ovariohysterectomy. Two other cats were euthanized 5 months after ovariohysterectomy; at least one of these cats had developed an abdominal mass that was not examined histologically. Only 2 cats with endometrial adenocarcinoma had disease-free intervals longer than 5 months after surgery. Metastasis was not detected in any mesenchymal tumor; however, these cats were either euthanized on discovery of the tumor or the tumor was first detected at necropsy.  相似文献   
102.
OBJECTIVE: To quantitate dose- and time-related magnitudes of interactive effects of morphine (MOR) and isoflurane (ISO) in horses and to characterize pharmacokinetics of MOR in plasma and the ventilatory response to MOR during administration of ISO. ANIMALS: 6 adult horses. PROCEDURE: Horses were anesthetized 3 times to determine the minimum alveolar concentration (MAC) of ISO in O2 and then to characterize the change in anesthetic requirement as defined by the alteration in ISO MAC following IV administration of saline (0.9% NaCl) solution and 2 doses of MOR (low dose, 0.25 mg/kg; high dose, 2.0 mg/kg). Arterial blood samples were obtained before and after MOR and analyzed. RESULTS: Mean +/- SD baseline ISO MAC was 1.43 +/- 0.06%. The ISO MAC did not change with time after administration of saline solution. Effects of MOR on ISO MAC varied. Maximal change in MAC ranged from -20.2 to +28.3% and -18.9 to +56.2% after low and high doses of MOR, respectively. Typical half-life of MOR in plasma was 40 to 60 minutes and related to dose. Mean PaCO2 increased from 70 mm Hg before MOR to 88 to 102 mm Hg for 30 to 240 minutes after the high dose of MOR. Recovery from anesthesia after administration of the high dose of MOR was considered undesirable and dangerous. CONCLUSIONS AND CLINICAL RELEVANCE: Our results do not support routine clinical use of MOR administered IV at dosages of 0.25 or 2.0 mg/kg as an adjuvant to anesthesia in horses administered ISO.  相似文献   
103.
The objective was to determine luteinizing hormone (LH) secretion and follicular dynamics in cattle following administration of 3 gonadorelin formulations that are commercially available in Canada. In experiment 1, nonlactating Holstein cows (n = 4 per group) were randomly assigned to receive 100 micrograms gonadorelin diacetate tetrahydrate, intramuscularly (C; Cystorelin, or FE; Fertagyl). Blood samples (for LH analysis) were collected 0, 1, 2, and 4 hours after treatment. In experiment 2, nonlactating Holstein cows (n = 10 per group) were randomly allocated to receive 100 micrograms gonadorelin, intramuscularly as follows: 2 mL of C; 1 mL of FE; or 2 mL of Factrel (FA, gonadorelin hydrochloride). Gonadorelin treatment was done on days 6 or 7 after ovulation and blood samples for LH analysis were collected at 0, 1, 2, 4, and 6 hours after treatment. Ovaries were examined by ultrasonography, twice daily, to detect ovulation. A replicate was conducted using only C (n = 10) or FE (n = 10); blood samples were collected at 0, 1, 2, 3, and 4 hours. In experiment 3, beef heifers (n = 10 per group) were randomly assigned to receive 1 of 3 GnRH gonadorelin treatments (as in the first phase of experiment 2) on days 6 or 7 after ovulation and blood samples were collected at 0, 0.5, 1, 1.5, 2, and 4 hours. In experiments 2 and 3, both mean and mean peak plasma LH concentrations were higher (P < 0.05) in cattle treated with C. The proportion of dominant follicles that ovulated was higher (P < 0.02) in Holstein cows treated with C than in those treated with FE or FA (18/19, 11/19, and 4/7, respectively), but there was no significant difference among the products in beef heifers (6/10, 6/10, and 4/10, respectively). No significant differences were found in the interval from treatment to the emergence of the next follicular wave. In summary, C induced a greater LH release and this resulted in a higher ovulatory rate in Holstein cows but not in beef heifers.  相似文献   
104.
A 2-year-old sexually intact male Paint horse weighing 427 kg (940 lb) was admitted for examination and treatment of intermittent non-weight-bearing lameness of the right hind limb of 1 week's duration. Radiography revealed a displaced Salter-Harris type-III fracture of the right femoral condyle with the sagittal component of the fracture line located in the intercondylar space and the transverse component exiting on the medial aspect of the femur. The fracture was repaired with a condylar screw plate designed for repair of femoral condylar fractures in humans. The owner reported by telephone 9 months after surgery that the horse was sound. To our knowledge, use of this particular implant system for fixation of a Salter-Harris type-III fracture on the medial side of the femur in a horse has not been described. Results in this horse suggest that this implant can be successfully used for repair of femoral condylar fractures in selected adult horses.  相似文献   
105.
Using a field-based model, mechanical transmission of porcine reproductive and respiratory syndrome virus (PRRSV) was assessed throughout a coordinated sequence of events that replicated common farm worker behavior during cold weather (< 0°C). The model involved fomites (boots and containers), vehicle sanitation, transport, and the movement of personnel. A field strain of PRRSV was inoculated into carriers consisting of snow and water, and carriers were adhered to the undercarriage of a vehicle. The vehicle was driven approximately 50 km to a commercial truck washing facility where the driver's boots contacted the carriers during washing, introducing the virus to the vehicle interior. The vehicle was then driven 50 km to a simulated farm site, and the driver's boots mechanically spread virus into the farm anteroom. Types of containers frequently employed in swine farms (styrofoam semen cooler, metal toolbox, plastic lunch pail, and cardboard animal health product shipping parcel) contacted drippings from footwear on the anteroom floor. The truck wash floor, vehicle cab floor mats, boot soles, anteroom floor, and the ventral surface of containers were sampled to track the virus throughout the model. Ten replicates were conducted, along with sham-inoculated controls. At multiple sampling points PRRSV nucleic acid was detected in 8 of 10 replicates. In each of the 8 PCR-positive replicates, infectious PRRSV was detected on the surfaces of containers by virus isolation or swine bioassay. All sham-inoculated controls were negative. These results indicate that mechanical transmission of PRRSV can occur during coordinated sequence of events in cold weather.  相似文献   
106.
Background: Consuming moderate amounts of lean red meat as part of a balanced diet valuably contributes to intakes of essential nutrients, in this study, we merged phenotypic and genotypic information to characterize the variation in lipid profile and sensory parameters and to represent the diversity among 15 cattle populations. Correlations between fat content, organoleptic characteristics and lipid profiles were also investigated. Methods: A sample of 436 largely unrelated purebred bulls belonging to 15 breeds and reared under comparable management conditions was analyzed. Phenotypic data -including fatness score, fat percentage, individual fatty acids (FA) profiles and sensory panel tests- and genotypic information from 11 polymorphisms was used. Results: The correlation coefficients between muscle total lipid measurements and absolute vs. relative amounts of polyunsaturated FA (PUFA) were in opposite directions. Increasing carcass fat leads to an increasing amount of FAs in triglycerides, but at the same time the relative amount of PUFAs is decreasing, which is in concordance with the negative correlation obtained here between the percentage of PUFA and fat measurements, as well as the weaker correlation between total phospholipids and total lipid muscle content compared with neutral lipids. Concerning organoleptic characteristics, a negative correlation between fiavour scores and the percentage of total PUFA, particularly to n-6 fraction, was found. The correlation between juiciness and texture is higher than with flavour scores. The distribution of SNPs plotted by principal components analysis (PCA) mainly reflects their known trait associations, although influenced by their specific breed allele frequencies. Conclusions: The results presented here help to understand the phenotypic and genotypic background underlying variations in FA composition and sensory parameters between breeds. The wide range of traits and breeds studied, along with the genotypic information on polymorphisms previo  相似文献   
107.
Background – Interleukin‐31 (IL‐31) is a member of the gp130/interleukin‐6 cytokine family that is produced by cell types such as T helper 2 lymphocytes and cutaneous lymphocyte antigen positive skin homing T cells. When overexpressed in transgenic mice, IL‐31 induces severe pruritus, alopecia and skin lesions. In humans, IL‐31 serum levels correlate with the severity of atopic dermatitis in adults and children. Hypothesis/Objective – To determine the role of IL‐31 in canine pruritus and naturally occurring canine atopic dermatitis (AD). Animals – Purpose‐bred beagle dogs were used for laboratory studies. Serum samples were obtained from laboratory animals, nondiseased client‐owned dogs and client‐owned dogs diagnosed with naturally occurring AD. Methods – Purpose‐bred beagle dogs were administered canine interleukin‐31 (cIL‐31) via several routes (intravenous, subcutaneous or intradermal), and pruritic behaviour was observed/quantified via video monitoring. Quantitative immunoassay techniques were employed to measure serum levels of cIL‐31 in dogs. Results – Injection of cIL‐31 into laboratory beagle dogs caused transient episodes of pruritic behaviour regardless of the route of administration. When evaluated over a 2 h period, dogs receiving cIL‐31 exhibited a significant increase in pruritic behaviour compared with dogs that received placebo. In addition, cIL‐31 levels were detectable in 57% of dogs with naturally occurring AD (≥13 pg/mL) but were below limits of quantification (<13 pg/mL) in normal, nondiseased laboratory or client‐owned animals. Conclusions – Canine IL‐31 induced pruritic behaviours in dogs. Canine IL‐31 was detected in the majority of dogs with naturally occurring AD, suggesting that this cytokine may play an important role in pruritic allergic skin conditions, such as atopic dermatitis, in this species.  相似文献   
108.
Improvements in seed germination, the early establishment of leaf cover, storage root development and the control of bolting would all increase the yield of sugar beet in the UK. Plant growth at these stages of development is controlled by genotype and by climatic factors acting through endogenous growth substances and is potentially capable of modification by applied growth regulators. For example, sugar beet responds to changes in daylength and spectral quality of light at the end of the day by increasing lamina and petiole growth, light interception and plant growth rate. Changes in endogenous gibberellins in young leaves of plants growing in different photoperiods and the responses of these leaves to applied gibberellic acid are presented as evidence for the involvement of gibberellins in leaf expansion in sugar beet.  相似文献   
109.
The sizes and velocities of drops in sprays from farm sprayers are considered in relation to their impaction on plant surfaces. Examples from a study being carried out at the National Institute of Agricultural Engineering (NIAE) are given. The results showed that young leaves of barley (cv Mazurka) and wild oats (Avena fatua L.) were difficult to wet, only the smallest drops applied (about 100 um diameter) being readily retained. In the context of weed control in cereals the importance of detrmining the effect of the form of plant deposits on herbicidal activity is discussed, and examples of results of a joint study between the NIAE and the Agricultural Research Council Weed Research Organization are given.  相似文献   
110.
Sugar beet, wheat, lettuce and cotton were grown in soil treated with [14C]permethrin, the crops being sown at intervals of 30, 60 and 120 days after treatment of the soil. The uptake of radioactive residues into these crops was measured. Low radioactive residues (up to 0.86 μg g?1) were detected in the mature plants sown 30 days after soil treatment, and this uptake declined significantly as the interval between soil treatment and sowing increased. Metabolites derived from the acid moiety of the permethrin molecule were shown to constitute the greater part of the residue transferring from the soil to the crops. (1RS)-cis- and (1RS)-trans-3-(2,2-dichlorovinyl)- 2,2-dimethylcyclopropanecarboxylic acid and 3-(2,2-dichlorovinyl)-1-methylcyclopropane-1,2-dicarboxylic acid were identified as the major acidic metabolites. The latter compound is a metabolite of permethrin which has not previously been identified in soil or plants.  相似文献   
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