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51.
AIM: To compare 2 treatments for anovulatory anoestrus (AA) in postpartum dairy cows. The treatments were combinations of gonadotropin-releasing hormone (GnRH) and prostaglandin F2𝛂 (PG) or progesterone (P4) and oestradiol benzoate (ODB).

METHODS: Forty AA cows from each of 5 herds were blocked by age (2 or >2 years old) and randomly assigned to 1 of 2 treatments. The first group (GPG) were treated with 250 𝛍g of a GnRH analogue, gonadorelin, followed 7 days later by 15 mg of the PG analogue, luprostiol. Two days later the cows were injected with 250 𝛍g of gonadorelin. Cows were artificially inseminated 16–24 h after the second GnRH injection. The second group (P4+ODB) were treated with an intravaginal P4 releasing device for 6 days, followed 24 h after device removal by injection of 1 mg of ODB. Cows were pregnancy tested 35–40 days after the initial insemination and twice again at 6–8 week intervals thereafter.

RESULTS: There was no significant difference between P4+ODB and GPG groups in the percentage of cows submitted for insemination in the first 7 days (94.0% vs 100% for P4+ODB vs GPG, respectively; p>0.3), in conception rate to first insemination within the first 7 days (43.6% vs 35.0% for P4+ODB vs GPG, respectively; p>0.2), in the percentage of cows conceiving in the first 28 days of the breeding period (68.0% vs 58.3%, P4+ODB vs GPG, respectively; p>0.1), or in median interval from the end of treatment to conception (20 vs 21days;p>0.1).

CONCLUSIONS: No differences in the reproductive performance of AA cows treated with either P4+ODB or GPG were detected. However, given the small number of animals enrolled, further data are required before the GPG protocol can be recommended for treatment of AA cows.  相似文献   
52.
Evaporative cooling during late gestation period improves post‐partum reproductive performance in Murrah buffaloes. To prove this hypothesis, sixteen pregnant dry Murrah buffaloes at sixty days pre‐partum were selected and divided into two groups of eight animals each. Group 1 of buffaloes (Cooled/CL) was managed under fan and mist cooling during dry period, whereas second group of buffaloes (non‐cooled/NCL) remained without the provision of cooling. After parturition, all the animals were managed under evaporative cooling till the end of experimental period. Reproductive performance in cooled (CL) and non‐cooled (NCL) groups, respectively, viz. 1st and 2nd ovulation from calving (48.63 ± 2.41, 69.25 ± 2.34 days and 57.75 ± 3.35, 93.63 ± 2.84 days); calving to conception interval (117.88 ± 4.21 days and 117.88± 4.21 days); conception rate (87.5% ± 2.16% and 57% ± 2.26%); and follicular diameter at the time of 1st and 2nd ovulation (14.84 ± 0.16, 15.75 ± 0.13 mm and 12.65 ± 0.13, 13.35 ± 0.11 mm) varied significantly (p < .05). Total peak oestrogen concentration was significantly (p < .05) higher in cooled (26.7 ± 1.32 pg/ml) relative to non‐cooled (20.7 ± 1.22 pg/ml) buffaloes. Time from onset of oestrus to ovulation varied significantly (p < .05) in cooled (32 ± 2.22 hr) and non‐cooled (40 ± 2.86 hr) buffaloes. The peak progesterone concentration reached to (4.25 ng/ml) in cooled group and (4.16 ng/ml) in non‐cooled group after first ovulation.  相似文献   
53.
Carbon structures with three-dimensional periodicity at optical wavelengths   总被引:1,自引:0,他引:1  
Porous carbons that are three-dimensionally periodic on the scale of optical wavelengths were made by a synthesis route resembling the geological formation of natural opal. Porous silica opal crystals were sintered to form an intersphere interface through which the silica was removed after infiltration with carbon or a carbon precursor. The resulting porous carbons had different structures depending on synthesis conditions. Both diamond and glassy carbon inverse opals resulted from volume filling. Graphite inverse opals, comprising 40-angstrom-thick layers of graphite sheets tiled on spherical surfaces, were produced by surface templating. The carbon inverse opals provide examples of both dielectric and metallic optical photonic crystals. They strongly diffract light and may provide a route toward photonic band-gap materials.  相似文献   
54.
To improve the Boer goat semen quality during cryopreservation process, three experiments were carried out to investigate the effect of (i) different concentration of ascorbic acid supplementation (ii) rate of cooling with chilled semen characteristics and (iii) method of freezing on post‐thaw Boer goat sperm using Tris‐based extender. Ascorbic acid at 8.5 mg/ml improved the sperm parameters (motility, integrity of membrane and acrosome, morphology and viability), compared to control in cooled samples (p < 0.05). With regard to other concentrations and post‐thawed parameters, ascorbic acid at 2.5–8.5 mg/ml led to higher percentages of sperm motility and integrities of membrane and acrosome when compared to control (p < 0.05). Slow cooling rises to higher percentages of sperm motility, acrosome integrity and viability, in comparison with fast cooling, in terms of cooled and frozen samples (p < 0.05). Programmable freezing method produced the higher percentages of sperm motility, integrities of membrane and acrosome and viability when compared to the freezing method of polystyrene box during goat sperm freezing (p < 0.05). In conclusion, chilled and post‐thawed sperm quality of Boer goat was improved when a Tris‐based extender supplemented with ascorbic acid was used at stages of different cooling rates and freezing methods.  相似文献   
55.
Epigenetic programs controlling development of the female reproductive tract (FRT) are influenced by the effects of naturally occurring bioactive agents on patterns of gene expression in FRT tissues during organizationally critical periods of foetal and perinatal life. Aberrations in such important cellular and molecular events, as may occur with exposure to natural or manmade steroid or peptide receptor-modulating agents, disrupt the developmental program and can change the developmental trajectory of FRT tissues, including the endometrium, with lasting consequences. In the pig, as in other mammals, maternal programming of FRT development begins pre-natally and is completed post-natally, when maternal effects on development can be communicated via signals transmitted in milk. Studies involving relaxin (RLX), a prototypic milk-borne morphoregulatory factor (MbF), serve as the basis for ongoing efforts to identify maternal programming events that affect uterine and cervical tissues in the neonatal pig. Data support the lactocrine hypothesis for delivery of MbFs to neonates as a specific consequence of nursing. Components of a maternally driven lactocrine mechanism for RLX-mediated signalling in neonatal FRT tissues, including evidence that milk-borne RLX is delivered into the neonatal circulation where it can act on RLX receptor (RXFP1) -positive neonatal tissues to affect their development, are in place in the pig. The fact that all newborn mammals drink milk extends the timeframe of maternal influence on neonatal development across many species. Thus, lactocrine transmission of milk-borne developmental signals is an element of the maternal epigenetic programming equation that deserves further study.  相似文献   
56.
Summary Bilateral superior check ligament desmotomy was performed on 31 Thoroughbred and 17 Standardbred horses as the sole method of treatment for superficial digital flexor tendonitis. Horses resumed racing between 6 and 19 months after surgery. Horses that were able to compete in 5 or more races without injury to the tendon again were considered to have had a successful return to racing. Twenty-five Thoroughbreds were suitable for later study and 13 of these (52%) raced on 5 or more occasions. Fifteen Standardbreds were suitable for later study and 10 of these (66%) raced on 5 or more occasions. Within the racing industry it is generally thought that about 20 to 30% of horses with superficial digital flexor tendonitis can return to racing after a prolonged rest. The results of this study suggest that bilateral superior check ligament desmotomy may improve the prognosis for a horse returning to racing after injury to the superficial digital flexor tendon.  相似文献   
57.
The pre‐medicant chosen may influence the ease with which gastroduodenoscopy (GD) is performed. The purpose of this study was to evaluate the relative ease of GD in cats under ketamine and isoflurane anesthesia after IM injection of hydromorphone (H, 0.1 mg kg?1), hydromorphone plus glycopyrrolate (HG, 0.1 mg kg?1 (H), 0.01 mg kg?1 (G)), medetomidine (M, 0.03 mg kg?1), or butorphanol (B, 0.4 mg kg?1). Eight cats were assigned randomly to receive each treatment in a cross‐over design with at least 7 days between treatments. Twenty minutes after pre‐medication, medetomidine produced greater (p = 0.001) sedation than the other treatments when assessed, using a subjective ordinal scale. The cats were injected with ketamine (10 mg kg?1 IM), orotracheally intubated, connected to a pediatric circle breathing system, and allowed to spontaneously breathe isoflurane in oxygen. Once end‐tidal isoflurane concentration was stable at 1.4% for 15 minutes, endoscopy was started. A single endoscopist (REG), who was unaware of the treatment used, performed all endoscopies. The endoscopist scored the difficulty of endoscopy subjectively (0–3). The significance of differences between treatments was evaluated using Friedman's test. Time for entering the stomach was 9.4 (4.7–15.9) (median (minimum–maximum)), 6.6 (5.2–11.7), 8.4 (6.3–16.5), and 7.7 (5.1–14.7) seconds and for entering the duodenum from the stomach was 20.5 (13.8–40.9), 18.2 (10.3–39.8), 20.2 (16.2–119.5), and 22.2 (11.8–83.8) seconds for H, HG, M, and B treatments, respectively. There were no significant differences in the time for, or difficulty of, endoscopy. We conclude that any of these drugs can be used satisfactorily at the doses and combinations tested to pre‐medicate cats prior to general anesthesia for GD.  相似文献   
58.
In this review, the terminology that is used to describe the bioavailability and ileal digestibility of AA in pig feed ingredients is defined. Aspects of the methodology to establish bioavailability and ileal digestibility values also are discussed, and recommendations about the use of these values are provided. Two main factors can contribute to differences between bioavailability and ileal digestibility of AA. First, some AA, such as Lys, may be absorbed in chemical complexes that preclude their use for metabolism. Second, fermentation in the upper gut may result in a net loss or gain of AA to the animal. In addition, dietary effects on the efficiency of using bioavailable AA intake for tissue growth or milk production should be considered and may be attributed to endogenous AA losses in the hindgut and the metabolic costs associated with endogenous gut protein synthesis and losses. Ileal digestibility values may be expressed as apparent ileal digestibility (AID), standardized ileal digestibility (SID), or true ileal digestibility (TID). These terms are used to specify how ileal endogenous AA losses are reflected in digestibility values. Ileal endogenous AA losses may be separated into basal losses, which are not influenced by feed ingredient composition, and specific losses, which are induced by feed ingredient characteristics such as levels and types of fiber and antinutritional factors. Values for AID are established when total ileal outflow of AA (i.e., the sum of endogenous losses and nondigested dietary AA) is related to dietary AA intake. A concern with the use of AID values is that these are not additive in mixtures of feed ingredients. This concern may be overcome by correcting AID values for defined basal endogenous losses of AA, which yields SID values. Furthermore, if the AID values are corrected for basal and specific endogenous losses, then values for TID are calculated. However, reliable procedures to routinely measure specific endogenous losses are not yet available. It is recommended that basal ileal endogenous losses of AA should be measured in digestibility experiments using a defined protein-free diet and that these losses are reported with observed AID and SID values. It is suggested that SID values should be used for feed formulation, at least until more information on TID values becomes available.  相似文献   
59.
ObjectiveTo evaluate the cardiopulmonary changes induced by intravenous butorphanol administration in guineafowl anesthetized with sevoflurane.Study designProspective experimental trial.AnimalsEight adult guineafowl (Numida meleagris) weighing 1.61 ± 0.49 kg were used for the study.MethodsBirds were anesthetized with sevoflurane and allowed to breathe spontaneously. After endotracheal intubation, end-tidal sevoflurane was adjusted to 1.0 individual sevoflurane MAC that was previously determined in triplicate using a standard bracketing technique. The brachial artery was catheterized for direct pressure measurement and blood sampling. Heart rate and rhythm were monitored by electrocardiography and respiratory rate was recorded. Baseline data were recorded 30 minutes after induction. Then, end-tidal sevoflurane was adjusted to 0.8 individual MAC and after 15 minutes physiologic variables were measured again. Subsequently, butorphanol (4 mg kg?1) was administered intravenously over 10 seconds and physiologic responses were recorded at 1, 5, 10, 15, 20, 30 and 45 minutes after administration.ResultsButorphanol administration was associated with arrhythmias in all birds, including second-degree atrioventricular block, sinus arrest, ventricular and supraventricular tachycardia and ventricular premature complexes. Heart rate and arterial blood pressures decreased significantly 1 minute after butorphanol administration. Two birds developed severe hypotension, apnea and ventricular fibrillation 5 minutes after administration, and one died.Conclusions and clinical relevanceThe butorphanol dose (4 mg kg?1) that produces clinically relevant sevoflurane MAC reduction in guineafowl caused severe adverse cardiopulmonary effects in two birds and was considered unsafe under the conditions used in this study.  相似文献   
60.
ObjectiveTo evaluate the cyclooxygenases (COX) inhibition, adverse effects and analgesic efficacy of dipyrone or meloxicam in cats undergoing elective ovariohysterectomy.Study designProspective, blinded, randomized, clinical study.AnimalsA total of 30 healthy young cats.MethodsThe cats were randomly assigned to three postoperative groups: D25 (dipyrone 25 mg kg?1 every 24 hours), D12.5 (dipyrone 12.5 mg kg?1 every 12 hours) and M (meloxicam 0.1 mg kg?1 every 24 hours). In the first 24 hours, the drugs were administered intravenously (IV), and then orally for 6 (dipyrone) or 3 days (meloxicam). Prostanoids thromboxane B2 and prostaglandin E2 concentrations served as indicators of COX activity and, with physiological variables and pain and sedation scores, were measured for 24 hours after first analgesic administration. Rescue analgesia (tramadol, 2 mg kg?1 IV) was provided if Glasgow feline composite measure pain scale (CMPS-Feline) ≥5. Laboratory tests included symmetric dimethylarginine and adverse effects were evaluated regularly up to 7 and 10 days after surgery, respectively. Parametric and nonparametric data were analyzed with two-way anova and Kruskal-Wallis tests, respectively (p < 0.05).ResultsIn the first half hour after analgesic administration, COX-1 activity was close to zero and remained significantly lower than before drug administration for 24 hours in all groups. The inhibition of COX-2 activity was significant for 30 minutes in all groups and up to 4 hours in group M. No alterations in laboratory tests or significant adverse effects were observed. Pain scores and need for rescue analgesia did not differ statistically among groups.ConclusionsDipyrone at both doses and meloxicam provided a nonselective inhibition of COX-1 and -2 activities and effective analgesia without causing significant adverse effects or laboratory tests alterations.Clinical relevanceDipyrone at both doses provides equally effective analgesia without causing adverse effects in cats undergoing ovariohysterectomy.  相似文献   
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