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71.
A rapid and simple nutrient addition technique was used for evaluating Al tolerance of six local upland rice (Oryza sativa L.) cultivars (BG35, BR21, DA25, DA26, DA14, and DA22) from Bangladesh and three IRRI rice, IR46, IR97, and IR45, cultivars from the Philippines. The plants were grown for 21 days with Al (0 μM, 140 μM, 280 μM or 560 μM) at pH 4.1. The roots were more affected by Al than the shoots. In rating cultivars for Al sensitivity, relative shoot weight (RSW) was found to be the best parameter due to the severe damage of the roots, irrespective of Al sensitivity. The cultivars were rated as Al tolerant (BG35, BR21, DA25, and DA26), mid‐tolerant (DA14, DA22, and IR46) and sensitive (IR97 and IR45) . More Al was retained in the roots of tolerant cultivars than in the mid‐tolerant or sensitive cultivars. In shoots, the Al concentration of tolerant cultivars was less than in the mid‐tolerant or in the sensitive cultivars and the inhibition of growth was proportional to Al concentration irrespective of Al tolerance. Therefore, the variation among cultivars in Al sensitivity could be related to the capacity of roots to retain Al from transport to the shoots.  相似文献   
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The effect of fibre degrading enzymes in combination with Lactobacillus plantarum on feed viscosity and pH and on solubilisation of non-starch polysaccharides (NSP) was studied in vitro using diets composed of cereals and soybean meal. The diet was incubated over time up to 24 h as liquid feed or liquid feed added L. plantarum and in addition both feeds were treated without or with fibre degrading enzymes.

Spontaneous fermentation developed in the liquid feed without L. plantarum and became noticeable after a period of 6 to 8 h, when pH began to drop. From 8 to 24 h there was a slow but steady reduction in pH down to a level of about pH 4.3. This development was irrespective of enzyme supplementation level. The L. plantarum treatment had already reached a pH of 4.2 after 8 h and a pH of 3.6 after 24 h.

The viscosity was reduced with supplementation with a high enzyme dose (6000 FXU and 600 FBG per kg diet), compared to the control diet (without enzymes). Treatment with L. plantarum (1.8 × 1011 CFU/kg feed) increased the viscosity over time, even with enzyme supplementation, compared to the control treatment.

Diets without and with enzyme supplementation and pre-treated as dry feed (control), liquid feed (incubated for 8 h) or liquid feed fermented with L. plantarum (incubated for 24 h), were subjected to an in vitro digestion procedure. Both pre-treatment as liquid feed and enzyme supplementation lead to a reduction in dry matter and in the insoluble NSP fraction during digestion in comparison with the control based on the original dry feed.

It may be concluded that enzyme supplementation to liquid or fermented feed may cause a reduction in the insoluble dietary fibre content as well as a reduction in feed viscosity, while the pH is not influenced.  相似文献   

75.
Quarter Milking for Improved Detection of Increased SCC   总被引:1,自引:0,他引:1  
The aim of the present study was to investigate whether milk composition and milk yield are changed in relation to a moderate increase in milk somatic cell count (SCC) in separate udder quarters. During a period of 13 weeks, 4158 bulk quarter milk samples from 68 cows were collected and analysed for milk SCC and milk composition. The sampling was done twice weekly. The cows were in different stages of lactation and in different lactation numbers. For calculations, three groups of cows were formed according to their SCC value. Group 1 cows, where all quarters had an SCC <100,000 cells/ml at all sampling occasions, were considered to be non-affected. Group 2 cows had one udder quarter with an increased SCC >100,000 cells/ml and 1.5-fold higher than the opposite quarter at one sampling occasion. For group 3 cows, the increase in SCC remained for several consecutive sampling occasions. Data from group 1 cows revealed that front and rear quarters were similar when compared with each other. For group 3 cows, the lactose content in milk decreased significantly, simultaneously with the increase in SCC and remained decreased for two sampling occasions after the initial increase in SCC. It was concluded that deviations in lactose content within front and rear quarters, respectively, may be a useful tool for detection of moderately increased SCC in separate udder quarters.  相似文献   
76.
The surgical treatment of impingement of dorsal spinous processes (DSPs) at 2 equine veterinary hospitals following a similar diagnostic and surgical protocol is described with special reference to the diagnosis and case selection. The diagnosis was made from clinical examination and results of radiography and diagnostic analgesia of the affected sites. Scintigraphy was also used as an aid to diagnosis at one hospital. Surgical treatment was generally recommended when conservative treatment, which included 3-9 months rest, intralesional corticosteroids and physiotherapy, had failed. The DSPs were approached through a midline incision in the skin and supraspinous ligament. They were resected using an oscillating saw. Postoperatively, horses were returned to lungeing work after 2 weeks and riding commenced at 3 months, in most cases, and by 6 months in all successful cases. From one to 6 DSPs between thoracic vertebra (T) 11 and lumbar vertebra (L) 3 were resected in individual horses. T15, 16 and 17 were the spines most commonly treated. Long-term follow-up information was obtained in 209 horses. Seventy-two percent of these horses returned to full work and a further 9% improved sufficiently to be used for some athletic work.  相似文献   
77.
In this case report, a Swedish flat‐coated retriever was diagnosed with an extensive Hepatozoon canis infection. The dog had a prominent monocytosis (14.0 × 109/L) with H canis gamonts detected in most monocytes, but none were found in the neutrophils. On the hematology system ADVIA 2120 peroxidase (PEROX) cytogram, most leukocytes were seen as a distinct cell population above the lymphocytes, which indicated that most of the cells were larger than lymphocytes and had weak myeloperoxidase staining. This distinct cell cluster appeared to be of a single cell type but was incorrectly divided by the ADVIA 2120 into lymphocytes, monocytes, and large unstained cells (LUC). The total leukocyte counts on the ADVIA 2120 WBC basophil (BASO) channel were much higher than that on the WBC PEROX count. The WBC BASO cytogram appeared abnormal with two parallel cell populations, so the BASO WBC count was considered erroneous. Polymerase chain reaction and DNA sequencing verified H canis infection. The dog was treated with subcutaneous imidocarb dipropionate (6 mg/kg) injections every other week. Post‐treatment hematology analyses indicated that the percentage of parasitized leukocytes decreased from 40% to 5% about 4 weeks after the start of treatment and were not found in any monocytes 6 weeks after the beginning of the treatment. In conclusion, H canis infection in this dog was associated with a strong monocytosis, and gamonts were present in many monocytes, which caused aberrant automated leukocyte counts to occur.  相似文献   
78.
1. In commercial free-range systems for laying hens, popholes to the outdoor range are often installed on one side of the house only. In multi-tier systems, it is possible that some individuals fail to access the range due to internal barriers to movement.

2. Five commercial multi-tier flocks from different units were studied. For each flock, two different colour markers were used to distinguish 200 birds roosting near the popholes (NP-Roost) and 200 birds roosting far from the popholes (FP-Roost) at night. The following day, counts of marked birds on the range and inside the house were performed.

3. Significantly more NP-Roost birds were observed in all areas of the outdoor range than FP-Roost birds the next day. Distance of FP area from the popholes was very strongly positively correlated with effect size in the adjacent range area.

4. Additionally, in the indoor area far from the popholes (FP) more FP-Roost birds were observed the next day than NP-Roost birds. In the indoor area near to the popholes (NP) more NP-Roost birds were observed the next day than FP-Roost birds.

5. These results suggest that roosting location is associated with differential range use when popholes are only available on one side of the shed as birds that roosted far from the popholes used the range less.  相似文献   

79.
Automatic milking systems (AMS) allow recording of alternative milkability measures. Our objectives were to estimate genetic parameters for teat cup attachment failures (AtF), incomplete milkings (IM), and handling time (HT), and their genetic correlations with box time (BT), udder traits and temperament. Teat coordinates were to measure udder conformation and teat placement. Genetic correlations were estimated between these traits and linear classification traits. Data on Swedish Holstein and Swedish Red cows in 19 AMS herds and 74 herds with conventional milking parlors were analyzed. HT and IM had low heritabilities, but that of AtF was 0.21–0.31. Genetic correlations between AtF and temperament were 0.44–0.71 (calm cows having low AtF). Short BT was weakly genetically associated with shallow udders with short and thin teats. High genetic correlations (0.91–0.98) were found between teat coordinate traits and linear classification traits. Thus, AMS records can be effectively used to select for improved milkability and temperament.  相似文献   
80.
The etiology of tooth resorption in the domestic cat remains unknown. The high prevalence and progressive nature of the disease complicates defining healthy control groups. In order to evaluate the possible influence of various life style changes on the prevalence of tooth resorption, healthy control groups are a prerequisite. This paper presents a prevalence study for tooth resorption in a free-ranging wild felidae population. Skulls from 46 free-ranging Eurasian lynx (Lynx lynx) were examined. The age of the animals had previously been estimated based on cementum annuli in the maxillary right canine tooth. The dental examination included both dental probing and radiographic imaging. Complicated fractures of the canine teeth were found in 9/46 (19.5%) skulls. In one fractured canine, apical root resorption and periapical lucency was detected. The root resorption was attributed to inflammatory resorption as a consequence of the initial dental trauma and necrotic pulp. No signs of tooth resorption were found in the remaining teeth. Supernumerary roots were detected in 18/46 skulls (39.1 %). Supernumerary "peg" teeth caudal to the mandibular first molar tooth were detected in 6/46 (13.0%) skulls. Although further studies on dental ultra-structure are needed, the Swedish Eurasian lynx may, in the future, be useful as a healthy comparative model for studies on the etiopathogenesis of tooth resorption in the domestic cat.  相似文献   
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