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31.
The objective of this study on common carp (Cyprinus carpio) was to obtain and predict the first cross-validated data of the fat content on market size carps using a non-invasive or non-destructive method in situ. The carps (1680 ± 388 g; n = 136) used were from a semi-intensive system and were on a different diet (cereal, pelleted and extruded diet). For the evaluation of the fat content, a Fish Fatmeter FM 692 from Distell.com. (FFM) and a manual measurement of back fat height using a digital calliper were used. For the prediction model, the following basic body measurements (variables) were used: total body length, body length, body height, the width of the body, and the circuit of the body. The body weight, weight of intestines, weight of gonads, weight of hepatopancreas, and fillet yield (%) were measured, and the Fulton coefficient was calculated. The study was focussed on evaluating the applicability of these methods and the accuracy of the obtained result, respectively. Results showed that all the rapid methods had a strong correlation. Multiple regression models with forward selection of variables were used throughout. The final prediction model between predicted and observed values for the fat content for FFM and calliper being adjusted index of determination is shown here (R adj 2  = 0.88; 5 variables and R adj 2  = 0.91; 7 variables), respectively.  相似文献   
32.

Objective

To compare the effects of MK-467 during isoflurane anaesthesia combined with xylazine or dexmedetomidine on global and gastrointestinal perfusion parameters.

Study design

Prospective, randomized experimental trial.

Animals

A total of 15 warmblood horses.

Methods

Horses were divided into two groups for administration of either dexmedetomidine (D) or xylazine (X) for premedication (D: 3.5 μg kg?1; X: 0.5 mg kg?1) and as constant rate infusion during isoflurane anaesthesia (D: 7 μg kg?1 hour?1; X: 1 mg kg?1 hour?1). During anaesthesia, heart rate, mean arterial blood pressure (MAP), systemic vascular resistance index (SVRI) and cardiac index (CI) were measured. Microperfusion of the colon, jejunum and stomach was measured using laser Doppler flowmetry. After 2 hours of stabilization, MK-467 (250 μg kg?1) was administered, and measurements were continued for another 90 minutes. For statistical analysis, the permutation test and Wilcoxon rank-sum test were used (p < 0.05).

Results

There were no differences in baseline measurements between groups. The MK-467 bolus resulted in a significant decrease in MAP (D: –58%; X: –48%) and SVRI (D: –68%; X: –65%) lasting longer in group D (90 minutes) compared to group X (60 minutes). While CI increased (D: +31%; X: +35%), microperfusion was reduced in the colon (D: –44%; X: –34%), jejunum (D: –26%; X: –33%) and stomach (D: –37%; X: –35%).

Conclusions and clinical relevance

Alpha-2-agonist induced vasoconstriction was reversed by the MK-467 dose used, resulting in hypotension and rise in CI. Gastrointestinal microperfusion decreased, probably as a result of insufficient perfusion pressure. An infusion rate for MK-467 as well as an ideal agonist/antagonist ratio should be determined.  相似文献   
33.
In the veterinary profession, the body condition score (BCS) plays an important role in the assessment of patients. It is a subjective, tactile method of evaluating body fat and muscle mass and is used in numerous species. Recognizing obesity (or the contrary, emaciation) is important for veterinarians treating reptiles and could be facilitated by a BCS. An existing form of body condition assessment already used is the body condition index (BCI), where the residuals from a regression of body mass on body length are calculated. Therefore, the goal of this study was to provide practitioners with a BCS system for corn snakes (Pantherophis guttatus) and to test it against the BCI. A total of 22 corn snakes (Pantherophis guttatus), stationed at the “Auffangstation für Reptilien” in Munich (reptile rescue centre, RRC), were subject of this study. Each had the following measurements taken: body weight (BW), snout–tail tip length (STL), snout–vent length (SVL) and circumference in the middle (C). Manual palpation of spine, area between vertebral spinous and transverse process, ribs and neck of each snake was performed by three veterinarians and assigned to specific scores by each examiner. A BCS (mean of examiners’ scores) was given to each snake according to manual palpation. The BCS system was chosen to be out of 5 in 0.5-point steps with 2.5 considered as ideal BCS. In the studied snakes, the BCS ranged from 1.5 to 3.5, with a median of 2.5. The median BW was 309 g (75–967 g), the median STL was 123 cm (79–153 cm), the median SVL was 104 cm (73–133 cm) and the median C was 7.5 cm (4.3–11 cm). BCS and BCI were positively correlated. A BCS includes a manual palpation of the animal and thus gives the examiner additional information to the objectively measured/calculated index.  相似文献   
34.
The cardiovascular system is the first functional organ in the embryo, and its blood vessels form a widespread conductive network within the organism. Blood vessels develop de novo, by the differentiation of endothelial progenitor cells (vasculogenesis) or by angiogenesis, which is the formation of new blood vessels from existing ones. This review presents an overview of the current knowledge on physiological and pathological angiogenesis in the horse including studies on equine endothelial cells. Principal study fields in equine angiogenesis research were identified: equine endothelial progenitor cells; equine endothelial cells and angiogenesis (heterogeneity, markers and assessment); endothelial regulatory molecules in equine angiogenesis; angiogenesis research in equine reproduction (ovary, uterus, placenta and conceptus, testis); angiogenesis research in pathological conditions (tumours, ocular pathologies, equine wound healing, musculoskeletal system and laminitis). The review also includes a table that summarizes in vitro studies on equine endothelial cells, either describing the isolation procedure or using previously isolated endothelial cells. A particular challenge of the review was that results published are fragmentary and sometimes even contradictory, raising more questions than they answer. In conclusion, angiogenesis is a major factor in several diseases frequently occurring in horses, but relatively few studies focus on angiogenesis in the horse. The challenge for the future is therefore to continue exploring new therapeutic angiogenesis strategies for horses to fill in the missing pieces of the puzzle.  相似文献   
35.
OBJECTIVE: To evaluate a combined transcutaneous carbon dioxide pressure (tcPCO(2)) and pulse oximetry sensor in sheep and dogs. ANIMALS: 13 adult sheep and 11 adult dogs. PROCEDURES: During inhalation anesthesia, for the first 10 minutes following sensor placement, arterial blood gas was analyzed and tcPCO(2) was recorded every 2 minutes. Subsequently, the animals were hyper-, normo-, and hypoventilated. The simultaneously obtained tcPCO(2) and PaCO(2) values were analyzed by use of Bland-Altman statistical analysis. RESULTS: Mean +/- SD overall difference between tcPCO(2) and PaCO(2) 10 minutes after sensor application was 13.3 +/- 8.4 mm Hg in sheep and 8.9 +/- 12 mm Hg in dogs. During hyper-, normo-, and hypoventilation, mean difference (bias) and precision (limits of agreement [bias +/- 2 SD]) between tcPCO(2) and PaCO(2) values were 13.2 +/- 10.4 mm Hg (limits of agreement, -7.1 and 33.5 mm Hg) in sheep and 10.6 +/- 10.5 mm Hg (limits of agreement, -9.9 and 31.2 mm Hg) in dogs, respectively. Changes in PaCO(2) induced by different ventilation settings were detected by the tcPCO(2) sensor with a lag (response) time of 4.9 +/- 3.5 minutes for sheep and 6.2 +/- 3.6 minutes for dogs. CONCLUSIONS AND CLINICAL RELEVANCE: The tcPCO(2) sensor overestimated PaCO(2) in sheep and dogs and followed changes in PaCO(2) with a considerable lag time. The tcPCO(2) sensor might be useful for noninvasive monitoring of changes but cannot be used as a surrogate measure for PaCO(2).  相似文献   
36.
ObjectivesTo determine the influence of ketamine or xylazine constant rate infusions on isoflurane requirements, cardiovascular parameters and quality of anaesthesia in horses undergoing elective surgery.Study designProspective, matched paired clinical trial.AnimalsFifty four adult Warmblood horses.MethodsAfter premedication with acepromazine, xylazine and butorphanol, anaesthesia was induced with ketamine-midazolam and maintained with isoflurane alone (I), isoflurane with either 1 mg kg−1 hour−1 ketamine (IK) or same dose of xylazine (IX). End tidal concentration of isoflurane (Fe’Iso) was adjusted by the same anaesthetist in all horses according to a scoring system. Dobutamine was infused to maintain mean arterial pressure (MAP) =70 mmHg. Arterial blood gases, heart rate (HR), respiratory rate, MAP and cardiac output (lithium dilution) were measured. Groups I and IK received xylazine before recovery. Recovery quality was scored.ResultsMean ± SD averaged Fe’Iso (volume%) was significantly lower in IX (0.95 ± 0.07) and IK (0.97 ± 0.08) than in I (1.16 ± 0.13). In group IX, HR was significantly lower and averaged MAP (90 ± 13 mmHg) significantly higher than in groups I (71 ± 7 mmHg) and IK (76 ± 7 mm Hg). Differences in other cardiopulmonary variables did not reach statistical significance. All horses recovered well with best score in group IX.ConclusionsBoth CRIs of xylazine and of ketamine resulted in pronounced reduction of isoflurane requirements and blood pressure support based on routinely monitored parameters. Cardiac output appeared well maintained in all three protocols, but lithium dilution induced errors mean the results are untrustworthy. The work requires repetition with another mode of measurement of cardiac output.Clinical relevanceAll three protocols provided good clinical anaesthesia with clinically acceptable cardiovascular effects.  相似文献   
37.
ObjectiveTo assess the effect of adjunctive gabapentin (GBP) on pain after thoracolumbar intervertebral disc surgery in dogs.Study designProspective, randomized, controlled, clinical, ‘blinded’ trial.AnimalsSixty-three client owned dogs undergoing hemilaminectomyMethodsDogs were assigned to two treatment groups. The GBP group received gabapentin 10 mg kg?1 orally every 12 hours starting before anaesthesia; the placebo (P) group received empty gelatin capsules. Background analgesia was initiated with intravenous levomethadone 0.6 mg kg?1 (as the combination ‘L-Polamivet) at anaesthesia induction, followed by a fentanyl patch and levomethadone 0.2 mg kg?1 subcutaneously every 8 hours for 24 hours. Pain was assessed by the short form of the Glasgow Composite Measure Pain Score (CMPS-SF) without the gait category, and by a Visual Analogue Scale (VAS). Serum GBP concentrations and cortisol concentrations were measured. Statistical analyses utilized chi square test, Kolmogorov-Smirnov test, two-way analysis of variances for repeated measurements, Wilcoxon test and Friedmann test as relevant. Correlations were tested by Spearman's and Pearson's correlation coefficient. p< 0.05 was considered significant.ResultsMedian CMPS-SF was lower in group GBP than in group P on days 0.5, 1, 4 and 5. However, CMPS-SF and VAS were not significantly different between groups. Both pain scores decreased significantly over time. Cortisol concentrations were not significantly different between groups. Minimum serum concentrations of GBP fell below the detection limit of 1 μg mL?1 in 6 of 29 and 7 of 28 dogs at 24 and 72 hours, respectively.Conclusions and clinical relevance10 mg kg?1 GBP orally twice a day did not result in a detectable reduction in pain behaviour compared to background opioid analgesia alone, although a trend to lower pain levels (p < 0.1) was present. Further studies are needed to determine if this is related to effective background analgesia or an ineffective dose of GBP.  相似文献   
38.
Hydromorphic soils should exhibit higher climate change feedback potentials than well aerated soils since soil organic matter (SOM) losses in them are predicted to be much larger than those of well aerated soils. To evaluate a combined feedback relationship between groundwater level (GWL) and total greenhouse gas (GHG) emission, a greenhouse microcosm experiment was performed by exposing three hydromorphic forest soil types that differed in carbon content to three water levels (?40, ?20 and ?5 cm) while plants were excluded. Net GHG fluxes were measured continuously. GHG concentrations plus oxygen were measured in soil air and soil water at different depths. In this study, soil type hardly affected GHG emissions but GWL did. CO2 emissions peaked at GWL of ?40 cm and declined on average to 65 and 33% during GWL at ?20 and ?5 cm, respectively. CH4 emissions showed the opposite pattern having the highest emission rates at GWL of ?5 cm and compared to that on average only ?3 and ?8% during GWL at ?20 and ?40 cm, respectively. The highest mean N2O emissions were detected at the intermediate GWL of ?20 cm, whereas it is reduced on average to 18% for GWL at ?40 cm and at ?5 cm. The highest greenhouse gas emissions (in CO2 equivalents) were calculated for GWL at ?20 cm. During GWL at ?40 cm, CO2 equivalent fluxes were only insignificantly lower. CO2 equivalent fluxes reduced explicitly in mean to 35% with GWL at ?5 cm. The outcome emphasizes that anaerobic SOM decomposition apparently produces a lower warming potential than aerobic SOM decomposition. Undoubtedly, hydromorphic soils have to be considered for climate–carbon feedback scenarios.  相似文献   
39.
The effects of two organic amendments, a municipal solid waste compost and a composted straw, on [U-ring- ]atrazine degradation pathways in a loamy soil (Grignon, Yvelines, France) were studied during laboratory incubations under controlled conditions. Three month conditionings were conducted under sterile or non-sterile conditions, with soil plus atrazine, organic amendment plus atrazine, or soil plus organic amendment. Then either an organic amendment or soil or atrazine was added, respectively, to these three treatments and incubated for an additional 3 months under non-sterile conditions. Both organic amendments modified the behaviour of atrazine in soil but via different processes. The addition of municipal compost increased atrazine sorption and decreased its availability for degradation by soil microorganisms. The effect of the composted straw was mainly related to its high enzymatic activity, which appeared to be responsible for the production of large amounts of hydroxyatrazine. This hydroxylation favoured the opening of the triazine ring and its subsequent mineralization in the soil. At the end of the incubations, less atrazine was mineralized in the presence of the two types of organic amendment, which both increased the formation of non-extractable residues of atrazine. The addition of municipal compost preserved larger amounts of extractable atrazine, while the addition of composted straw enhanced hydroxyatrazine production. In all cases, the greatest effects were found when atrazine was directly in contact with the organic amendment during conditioning.  相似文献   
40.
Transition into higher education requires students to adjust to a new environment while showing greater independence in managing their own academic and personal life. This is often more difficult for international students who have to adjust to a different country, culture, and potentially another language. A cohort of first-year veterinary medicine students (17% international students) was investigated at a UK university using qualitative and quantitative questionnaires rating first-year experience and support services and statistical analysis of students' assessment performance. While the overall undergraduate perception was that they had learned a lot and progressed well, students in both groups struggled to cope with the workload. The non-UK educated students and students with English as a foreign language also struggled more with teaching delivery in lectures and participation in self-directed group learning and were more likely to feel that the veterinary degree program was too difficult. There was no statistical difference in how British and international students perceived the support system, although it was noticeable that the level of tutorial support was perceived as tutor-dependent. The international students particularly struggled with the assessments in early modules and also with the spot assessment method. However, in the practical assessments, using observed, structured practical exam stations, international and British students performed equally well. Increased support in the initial transition time, especially with regard to communication skills and confidence required for interactive teaching and learning environments such as small-group teaching, as well as increased time for specific assessment types, might benefit the needs of many international students.  相似文献   
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