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991.
Tropical Animal Health and Production - The objective of this study was to evaluate the nutritional value of different roughage sources as an exclusive feed for goats and sheep from the...  相似文献   
992.
The objectives were to conduct a genetic evaluation of residual feed intake (RFI) and residual feed intake adjusted for fat (RFIFat) and to analyse the effect of selection for these traits on growth, carcass and reproductive traits. Data from 945 Nellore bulls in seven feed efficiency tests in a feedlot were analysed. Genetic evaluation was performed using an animal model in which the feed efficiency test and age of the animal at the beginning of the test were considered as a systematic effect. Direct additive genetic and residual effects were considered as random effects. Correlations and genetic gains were estimated by two‐trait analysis between feed efficiency measures (RFI and RFIFat) and other traits. Feed conversion showed low heritability (0.06), but dry matter intake (DMI), average daily gain, RFI, RFIFat, metabolic body weight and scrotal circumference measured at 450 days of age (SC450) showed moderate to high heritability (0.49, 0.28, 0.33, 0.36, 0.38 and 0.80, respectively). Similarly, ribeye area, backfat thickness, rump cap fat thickness, marbling score and subcutaneous fat thickness also had high heritability values (0.46, 0.37, 0.57, 0.51 and 0.47, respectively). Genetic correlations between RFI and SC450 were null, and between RFIFat and SC450 were strongly positive. Genetic and phenotypic correlations of RFI and RFIFat with carcass traits were not different from zero, as correlated responses for carcass traits were also not different from zero. The Nellore selection for feed efficiency by RFI or RFIFat allows the recognition of feed efficient animals, with DMI reduction and without significant changes in growth and carcass traits. However, because of the observed results between RFIFat and SC450, selection of animals should be analysed with caution and a preselection for reproductive traits is necessary to avoid reproductive impairments in the herd.  相似文献   
993.
Ovarian tumours in mares represent 2.5% to 6% of the most frequent neoplasms found in the equine species, with a higher chance of benignity. This study aims to describe a case of two different tumours found in the same ovary of a mare that presented clinical signs of suppressed oestrous cycle during 5 years. After unilateral ovariectomy, the ovary was sent to the histopathology examination which determined a mixed tumour of granulosa cell and leiomyosarcoma. After treatment, the mare returned to oestrus and got pregnant in the next season.  相似文献   
994.
This study investigated the feasibility of applying fixed‐time (cryopreserved) embryo transfer in ewes. Embryos (n = 106) were non‐surgically recovered from superovulated donors (n = 39) on day 6–7 after oestrus. Straws containing one or two embryos (morulae and/or blastocysts) subjected to either slow freezing (SF, n = 62) or vitrification (VT, n = 44) were randomly used within fixed‐time embryo transfer on Day 8.5. Recipient ewes were nulliparous (n = 58) bearing corpora lutea after synchronous oestrous induction protocol. The pregnancy rate was higher (p = .03) in SF (39.4%) than VT (16.9%) and survival rate tended (p = .08) to be higher in SF than in VT (25.8% vs. 15.9%). Lambing rates were similar (p = .13) between SF (20.9%) and VT (15.9%). Embryos recovered by non‐surgical route after cervical dilation treatment and later cryopreserved by either slow freezing or vitrification produced reasonable pregnancy rates after FTET.  相似文献   
995.
This study assessed the effect of phosphites (Mg, Zn, Ca, K) on papaya (‘Sunrise Solo’) anthracnose (Colletotrichum gloeosporioides). Surface-sterilised wounded (2mm) fruits were inoculated (50µL; 106 con/mL) with C. gloeosporioides and then the products were applied. The lesion diameters (LD) and the physico-chemical properties were analysed. Assays in vitro and in vivo were carried out with phosphites. The results in vitro indicated that the phosphites were effective in reducing the mycelial growth and conidia production for all doses [Phosphite Mg – 0.75, 1.5, 3 ml/l (40% P2O5 + 6% Mg) Fitofos Mg; Phosphite Zn - 1.25, 2.5, 5 ml/l (40% P2O5 + 10% Zn)]; Phosphite Ca - 1.5, 3, 6 ml/l (30% P2O5 + 7% Ca)]; Phosphite K - 1.25, 2.5, 5 ml/l (40% P2O5 + 20% K2O)]. Concentration experiments on disease control showed that Phosphite-Ca at 6 ml/l (30% P2O5 + 7% Ca) significantly reduced the LD. Fruit treated with phosphite-Ca maintained physico-chemical properties of papaya fruits.  相似文献   
996.
This study was performed to evaluate the use of glycerol-preserved equine amniotic membrane as replacement for full-thickness corneal defects in dogs. Eighteen mixed-breed dogs were used. A perilimbal, full-thickness, 5 mm square corneal defect was created surgically, and a donor implant of equine amniotic membrane of the same size and shape sutured in place with 10–0 nylon simple interrupted sutures. Corneal edema was observed near the implant 24 h after surgery, but was absent after 1 week. Granulation tissue and corneal vascularization superficial to the implant were noticed on postoperative day 7, but were absent on day 30. Corneal vascularization persisted until the end of the experiment. There was no fluorescein retention by postoperative day 30. There was slight clearing of the corneal implant by postoperative 30, and slight pigmentation of the donor implant observed at postoperative day 180. An acute inflammatory process as well as fibroblasts were present at early postoperative stages. At postoperative day 60 there was no inflammatory cellular infiltrate, but fibroblasts and fibrosis were present. Corneal architecture was restored at the end of the experiment, with a layering of the epithelium–stroma–debris of amniotic membrane–stroma–endothelium present, and pigmentation and vascularization present in the deep layers of the cornea. Although vascularization indicated some degree of graft rejection, the clinical and histological evidence indicates that the xenologous amniotic membrane can be useful as a tectonic graft in the repair of full-thickness lesions of the cornea of dogs.  相似文献   
997.
998.

Objective

To assess the feasibility, success rate, onset, duration and extent of motor/sensory block following intrathecal injection of lidocaine in bearded dragons (Pogona vitticeps).

Study design

Prospective experimental study.

Animals

A group of eight adult bearded dragons (0.333 ± 0.048 kg).

Methods

The animals were sedated with alfaxalone (15 mg kg?1) subcutaneously. Neuraxial injections were performed with 1% lidocaine (2 mg kg?1) or 0.9% sodium chloride (0.2 mL kg?1) in all animals with a 7 day interval. If the initial injection did not result in motor block of the pelvic limbs within 10 minutes, a second injection was performed at the same dose. Measurements consisted of bilateral mechanical stimulation of limbs; 25%, 50%, and 75% of the trunk’s length; and cloacal tone. Animals were monitored for any untoward side effects by monitoring heart rate (HR), respiratory rate, righting reflex and head position.

Results

Success rate following the first injection of lidocaine was 50% (four out of eight animals) and increased to 75% (six out of eight animals) following a second injection. Onset of motor/sensory block occurred within 5 minutes in all successful injections. Duration and extent were variable, with most bearded dragons presenting motor/sensory block of cloaca and pelvic limbs (six out of six) and 25% of the trunk (five out of six) with mean ± standard deviation (range) duration of 49 ± 28 (25–100), 48 ± 25 (25–90) and 40 ± 14 (25–50) minutes, respectively. Confirmation of intrathecal injection by aspiration of cerebrospinal fluid was not possible. Neuraxial lidocaine significantly increased depth and duration of sedation, with a transient increase in HR, compared with saline.

Conclusion and clinical relevance

Neuraxial lidocaine is a feasible technique with moderate success rate and low risk of complication in bearded dragons. This technique has potential for improving the management of anesthesia in this species.  相似文献   
999.
OBJECTIVE: To compare the quality of induction and recovery, degree of muscle relaxation, clinically apparent potency and cardiopulmonary effects of racemic ketamine or S(+)-ketamine when used for total intravenous anesthesia in horses. STUDY DESIGN: Prospective randomized clinical trial ANIMALS: Sixteen healthy stallions (323 +/- 99 kg), with a mean age of 6.2 years, undergoing castration. METHODS: Horses were pre-medicated with romifidine IV, 15 minutes before induction of anesthesia. Each animal was then randomly allocated to receive either diazepam and ketamine (DK) or diazepam and S(+)-ketamine (DKS) at similar doses to induce anesthesia. For maintenance of anesthesia, 1/4 of the initial bolus of ketamine alone or S(+)-ketamine alone was administered, as required. Heart rate (HR), respiratory rate (RR) and systolic blood pressure were measured before and at 10-minute intervals during recumbency. Time from induction to lateral recumbency, time from induction to first additional dose, time from last additional dose to return to sternal posture and time from last additional dose to standing were recorded, and a subjective evaluation of quality of induction, endotracheal intubation, muscle relaxation and quality of recovery was recorded. RESULTS: The quality of the induction and duration of anesthesia were similar in both groups. HR, RR and systolic blood pressure were not significantly different between groups. Although some animals which received DKS showed some minor excitatory effects (25% of them) during the induction of anesthesia, these animals received 32% fewer doses for the maintenance of anesthesia and the recovery scores were better. CONCLUSIONS AND CLINICAL RELEVANCE: S(+)-ketamine showed some advantages over racemic ketamine, such as less anesthetic agent being required and better overall recovery from anesthesia. Further studies are needed to obtain the optimum induction dose for the S(+)-ketamine.  相似文献   
1000.
Five species of mycoplasma are associated with several rat diseases. Mycoplasma pulmonis is the most important and most studied, possibly causing disease in rats and undermining the validity of laboratory experiments. M. pulmonis was isolated in 144/240 laboratory rats and identified by PCR in 155/240. This species was also detected in 12 human individuals (technicians of a laboratory animal house hold) in contact with these rats. The results were confirmed by sequencing of DNA products. Mycoplasma species are host specific; however, M. pulmonis was identified in humans, suggesting a case of unspecific colonization. Statistical analysis shows a greater risk for M. pulmonis colonizing individuals who are exposed to infected rats in animal facilities than individuals who do not. The detection of M. pulmonis in humans indicates a new status for this mollicute mycoplasmas in animal-holding facilities.  相似文献   
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