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81.
The use of Piromen, a polysaccharide complex of Pseudomonas aeroginosa, has been investigated in 21 calves by a test of marrow granulocyte reserves. The maximal increase in peripheral granulocytes (ΔG) was determined following multiple intravenous and sub-cutaneous injections of Piromen at various time intervals and was correlated with the mature marrow granulocytes on bone marrow smear differentials. Five ug Piromen per kg body weight, by the subcutaneous route, was found to give a mean ΔG of 5200/mm3, very similar to the ΔG of 5300/mm3 obtained in man with 0.1 ug/kg intravenous Piromen injections. Clinical effects in calves were minimal with the subcutaneous route as compared to the response following intravenous Piromen injections.  相似文献   
82.
Phenobarbital was administered to eight healthy cats as a single intravenous dose of 10 mg/kg. Serum phenobarbital concentrations were determined using an immunoassay technique. The intravenous data were fitted to one-, two- and three-compartment models. After statistical comparison of the three models, a two-compartment model was selected. Following intravenous administration, the drug was rapidly distributed (distribution half-life = 0.046 +/- 0.007 h) with a large apparent volume of distribution (931 +/- 44.8 mL/kg). Subsequent elimination of phenobarbital from the body was slow (elimination half-life = 58.8 +/- 4.21 h). Three weeks later, a single oral dose of phenobarbital (10 mg/kg) was administered to the same group of cats. A one-compartment model with an input component was used to describe the results. After oral administration, the initial rapid absorption phase (absorption half-life = 0.382 +/- 0.099 h) was followed by a plateau in the serum concentration (13.5 +/- 0.148 micrograms/mL) for approximately 10 h. The half-life of the terminal elimination phase (76.1 +/- 6.96 h) was not significantly different from the half-life determined for the intravenous route. Bioavailability of the oral drug was high (F = 1.20 +/- 0.120). Based on the pharmacokinetic parameters determined in this study, phenobarbital appears to be a suitable drug for use as an anticonvulsant in the cat.  相似文献   
83.
84.
The virulence of a strain of hog cholera virus isolated during an outbreak of mild disease in pigs in New South Wales in 1960/61 (the NSW strain) was compared over 11 days with that of a virulent strain by inoculating 8 pigs with each virus and comparing the ensuing clinical signs and pathology. Both viruses caused persistent pyrexia and leukopenia, the NSW strain 4 to 5 days and the virulent strain 3 days, after inoculation. Few other clinical signs were observed in the pigs inoculated with the NSW strain. In contrast, all pigs inoculated with the virulent strain became progressively depressed and incoordinated, and were killed between days 6 and 9. Bronchopneumonia and swollen, reddened lymph nodes were observed in pigs inoculated with both viruses. Few other gross lesions were observed with the NSW strain, but some pigs receiving the virulent strain had pustules in the tonsil and the anterior oesophagus, petechial haemorrhages in the kidney, and small infarcts at the margins of the spleen. There were marked differences in the histopathology, both in the variety of organs affected and the severity of lesions in individual organs. Suppurative bronchopneumonia occurred in both groups. Other changes in the pigs affected with the NSW strain were colitis, mild cerebral vasculitis, necrosis, haemorrhage and neutrophil infiltration in some lymph nodes and spleens. In pigs infected with virulent virus the cerebral vasculitis was so severe that there was necrosis of cells within the vessel walls.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
85.
A study was conducted to examine the relationship of delta bilirubin to traditional bilirubin fractions to determine if delta bilirubin might assist in differentiating causes of hyperbilirubinemia in the horse. A recently introduced thin-film method was used for delta bilirubin determination. Thin-film and the traditional diazo methods were used for determining total, unconjugated, and conjugated bilirubin fractions. Sera from 38 healthy and 85 sick horses were examined.

Thin-film serum delta bilirubin determination does not appear to assist in differentiating causes of unconjugated hyperbilirubinemia in horses. There was good correlation between thin-film and diazo-determined total bilirubin and bilirubin fractions. Only small changes in reference limits would appear to be necessary for clinical application of the thin-film bilirubin methods used in this study.

  相似文献   
86.
OBJECTIVE: To evaluate the accuracy of point-of-care tests for the diagnosis of disseminated intravascular coagulation (DIC) in dogs and assess the correlation and agreement of results between point-of-care and laboratory tests in the evaluation of hemostatic function. DESIGN: Prospective case series. ANIMALS: 59 critically ill dogs (affected dogs) with clinical signs of diseases known to predispose to DIC and 52 clinically normal dogs. PROCEDURES: Accuracy of the point-of-care tests (activated clotting time [ACT], estimated platelet count and number of schizocytes from a blood smear, plasma total solids [TS] concentration, and the protamine sulfate test) was evaluated, using receiver operating characteristic curves and likelihood ratios. A strategy, using likelihood ratios to calculate a posttest probability of DIC, was tested with 65% used as a threshold for initiation of treatment. Results of laboratory tests (coagulogram and plasma antithrombin III activity) were used as the standard for comparison in each dog. RESULTS: ACT and estimated platelet count provided the best accuracy for detection of DIC. The plasma TS concentration, schizocyte number, and protamine sulfate test had poor accuracy. The strategy using post-test probability of DIC identified 12 of 16 affected dogs that had DIC. Estimated platelet count was correlated and had acceptable clinical agreement with automated platelet count (r = 0.70). The plasma TS (r = 0.28) concentration and serum albumin (r = 0.63) concentration were not accurate predictors of plasma antithrombin III activity. The ACT did not correlate with activated partial thromboplastin time (r = 0.28). CONCLUSIONS AND CLINICAL RELEVANCE: Strategic use of likelihood ratios from point-of-care tests can assist clinicians in making treatment decisions for dogs suspected to have DIC when immediate laboratory support is unavailable.  相似文献   
87.
Lectins are primordial molecules with multiple known functions. They have been known to exist in fish and other animals for decades and were initially identified as (hem)agglutinins. Demonstration of the importance of vertebrate lectins in innate immunity is a recent effort and is still largely unrealised for fish. This mini-review will tabulate those fish lectins identified since the last major review. In addition, particular lectins for which either functional relevance or functional or structural heterogeneity has been demonstrated are discussed in greater detail.  相似文献   
88.
89.

Objective

To evaluate cardiopulmonary and recovery characteristics of horses administered total intravenous anesthesia (TIVA) with xylazine and ketamine combined with midazolam or propofol.

Study design

Randomized crossover study.

Animals

A group of eight adult horses, aged 7–22 years, weighing 493–740 kg.

Methods

Horses were administered xylazine (1 mg kg?1) intravenously (IV), and anesthesia was induced with ketamine (2.2 mg kg?1) IV. Anesthesia was maintained for 45 minutes via IV infusion of xylazine (0.016 mg kg?1 minute?1) and ketamine (0.03 mg kg?1 minute?1) combined with midazolam at 0.002 mg kg?1 minute?1 (MKX), propofol at 0.05 mg kg?1 minute?1 (PKXlow) or propofol at 0.1 mg kg?1 minute?1 (PKXhigh). Additional ketamine was administered if a horse moved spontaneously. Cardiopulmonary variables, blood gases, lactate concentration, packed cell volume and total solids were recorded before sedation (baseline), at 10, 20, 30 and 45 minutes during TIVA and 10 minutes after standing. Recovery variables and quantitative recovery scores were compared. Significance was set at p < 0.05.

Results

Additional ketamine was required for 50% of MKX horses. Systolic arterial pressure was elevated in MKX at 20 minutes compared with baseline (p = 0.043), at 10 and 20 minutes compared with PKXhigh (p = 0.007, p = 0.024) and at 20 and 30 minutes compared with PKXlow (p = 0.009, p = 0.02). MKX horses (5/8) were hypertensive compared with PKXlow (1/8; p = 0.017). All horses became hypoxemic (PaO2 ≤80 mmHg; 10.7 kPa) during TIVA. Recovery variables did not differ among treatments.

Conclusions and clinical relevance

PKXlow and PKXhigh had similar cardiopulmonary and recovery performance compared with MKX. PKX combinations provided superior quality of anesthesia to that of MKX. A combination of propofol, ketamine and xylazine administered as TIVA can be used in horses to provide anesthesia for short procedures. Supplemental oxygen is recommended.  相似文献   
90.
Dogs were classified into a number of disease categories according to hematological, cytological and serochemical changes. Aspiration and core bone marrow biopsies were examined in 128 dogs in the various disease categories and compared to marrow samples in 36 dogs which appeared clinically normal. Differential cell counts on bone marrow smears were examined in relation to the blood variables in all animals. Blood and bone marrow data (group means) were compared among the normal and disease groups. Anemia, responsive and poorly responsive was the most frequent blood abnormality. Most dogs in the thrombocytopenia group had increased numbers of megakaryocytes in the marrow but two dogs had a marked decrease. The frequency of serious alteration of marrow production of the erythroid, myeloid and megakaryocytic series was less than anticipated. Marrow hemopoiesis was not significantly compromised in dogs with lymphoma or in dogs with other types of cancer. Bone marrow examination was necessary for the diagnosis of myelofibrosis and pancytopenia and was very helpful in the groups with insufficient change in the blood to permit a definitive diagnosis to be made. The myeloid-erythroid ratio was a useful indicator of marrow response while the erythroid maturation index and the myeloid maturation index were useful for identification of altered patterns of maturation (ineffective hemopoiesis). The reticulocyte response in absolute numbers is the most efficient and clinically relevant measure of erythroid response.  相似文献   
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