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61.
Between 2011 and 2012, a total of 896 pig fecal samples were collected from nine provinces in Korea, and 50 salmonella enterica susp. enterica serovar Typhimurium (S. Typhimurium) was isolated. The characteristics of the 50 strains were analyzed, and 4 strains were identified as Salmonella enterica subsp. enterica serovar 4,[5],12:i:-. Salmonella 4,[5],12:i:- could not be distinguished from S. Typhimurium through phage typing, antimicrobial resistance testing or multiple-locus variable-number tandem repeat analysis (MLVA). However, among the four Salmonella 4,[5],12:i:- strains, one (KVCC-BA1400078) was identified as a Salmonella 4,[5],12:i:- clone isolated from humans in the United States, and another (KVCC-BA1400080) was identified as DT193, which has been primarily isolated from humans and animals in European countries. The presence of Salmonella 4,[5],12:i:- in Korea poses a significant threat of horizontal transfer between pigs and humans.  相似文献   
62.
Different interventions are being tested for restoration of the youthfulness of adult mouse-derived fibroblasts. However, fundamental issues, such as the decline of adult mouse-derived fibroblast activity with age, remain unresolved. Therefore, in this study, we examined whether treatment with collagen complexes has beneficial effects on the rejuvenation or reprogramming of adult mouse-derived fibroblasts. Further, we investigated the mechanisms of rejuvenation of adult mouse-derived fibroblasts during treatment with total collagen complexes. We isolated total collagen complexes from the tails of young mice and cultured adult mouse-derived fibroblasts with or without the collagen complexes. When compared with fibroblasts cultured without collagen complexes, adult-derived fibroblasts cultured with collagen complexes over five consecutive passages showed a more youthful state, expanded at a higher rate, and exhibited reduced spontaneous cell death. The fibroblasts cultured in the presence of collagen complexes also showed extensive demethylation in the promoter regions of cell cycle-related genes such as PCNA, increased proliferation, and decreased senescence. In addition, the efficiency of reprogramming of fibroblasts to become induced pluripotent stem (iPS) cells was significantly higher in young- and adult-derived fibroblasts cultured with collagen complexes than in adult-derived fibroblasts cultured alone. Furthermore, mechanistic evidence shows that genes involved in anti-proliferative pathways, including Ink4a/Arf locus genes and p53, were downregulated in fibroblasts exposed to collagen complexes. Interestingly, our results suggest that the rejuvenation process was mediated via the α2β1 integrin-dependent Bmi-1 pathway. Thus, collagen complexes both stimulate proliferation and inhibit cell death and growth arrest in fibroblasts, which appears to be a promising approach for improving the efficiency of reprogramming.  相似文献   
63.
A one-year-old, castrated male domestic short hair cat was admitted with a history of anorexia, regurgitation and pyrexia for two days. Fever and leukocytosis were identified. There were a large soft tissue density oval mass in the caudal mediastinum on thoracic radiographs, a fluid-filled oval mass in the caudal mediastinum on ultrasonography, and left-sided and ventrally displaced and compressed esophagus on esophagram. On esophageal endoscopy, there were no esophageal abnormalities. CT findings with a fluid filled mass with rim enhancement indicated a caudal mediastinal paraesophageal abscess. The patient was treated with oral antibiotics, because the owner declined percutaneous drainage and surgery. The patient was admitted on emergency with severe respiratory distress; and ruptured abscess and deteriorated pleuropneumonia were suspected. With intensive hospitalization care and additional antibiotic therapy, the patient had full recovery.  相似文献   
64.
X-chromosome inactivation (XCI) is an epigenetic process that equalizes expression of X-borne genes between male and female eutherians. This process is observed in early eutherian embryo development in a species-specific manner. Until recently, various pluripotent factors have been suggested to regulate the process of XCI by repressing XIST expression, which is the master inducer for XCI. Recent insights into the process and its regulation have been restricted in mouse species despite the evolutionary diversity of the process and molecular mechanism among the species. OCT4A is one of the represented pluripotent factors, the gate-keeper for maintaining pluripotency, and an XIST repressor. Therefore, in here, we examined the relation between OCT4A and X-linked genes in porcine preimplantation embryos. Three X-linked genes, XIST, LOC102165544, and RLIM, were selected in present study because their orthologues have been known to regulate XCI in mice. Expression levels of OCT4A were positively correlated with XIST and LOC102165544 in female blastocysts. Furthermore, overexpression of exogenous human OCT4A in cleaved parthenotes generated blastocysts with increased XIST expression levels. However, increased XIST expression was not observed when exogenous OCT4A was obtained from early blastocysts. These results suggest the possibility that OCT4A would be directly or indirectly involved in XIST expression in earlier stage porcine embryos rather than blastocysts.  相似文献   
65.
Classical swine fever (CSF) is a highly contagious systemic hemorrhagic viral disease of pigs. Wild boar plays a crucial role in the epidemiology of CSF. Between 2010 and 2014, samples were collected nationwide from 6,654 wild boars hunted in South Korea. Anti-CSF antibodies were identified in 0.59% (39 of 6,654) of the wild boar samples using a virus neutralization test and were primarily detected in wild boars living close to the demilitarized zone and the area of the Taebaek Mountains surroundings. The CSF virus (subgroup 2.1b) was isolated from two wild boars captured in a nearby border area. The criteria used to define high-risk areas for targeted CSF surveillance in South Korea should be further expanded to include other regions nationwide.  相似文献   
66.
This study evaluated anesthesia quality, degree of analgesia and cardiorespiratory parameters after intramuscular (IM) injection of a combination of butorphanol (0.1 mg/kg), medetomidine (10 µg/kg) and alfaxalone (1.5 mg/kg) in ten healthy adult Beagle dogs. Rectal temperature (T), heart rate (HR), respiratory rate (fR), arterial pressure, arterial blood gases and M-mode echocardiographic left ventricular (LV) indices were measured before drug administration and every 10 min thereafter until extubation. Mean duration of anesthesia, recovery and analgesia were 89 ± 17, 6 ± 1 and 80 ± 12 min. HR, fR, partial pressure of arterial CO2 and O2, arterial pressure, and LV contractility were significantly altered during anesthesia. IM administration of the drug combination provided acceptable anesthesia, but produced substantial cardiorespiratory suppression.  相似文献   
67.
This study demonstrated magnetic resonance imaging (MRI) and computed tomography for large-sized splenic hemangiosarcoma. Radiography and ultrasonography revealed the presence of a large-sized soft-tissue mass in the cranial abdomen. Computed tomography showed hypoattenuating mass. The mass was located in contact with liver, spleen and stomach, and the origin of the mass remained ambiguous. The mass was T2-hyperintense and T1-hypointense with mild contrast enhancement. MRI allowed a differentiation between large-sized tumor and neighboring normal structure, and the mass was consequently identified as arising from spleen. These results suggested that MRI might be a useful tool to visualize large-sized splenic tumors and improve the accuracy of diagnosis.  相似文献   
68.
Differentiating hepatocellular disease versus biliary obstruction can be challenging in dogs presented for icterus. The purpose of this prospective study was to determine the feasibility of percutaneous contrast ultrasound‐guided cholecystography in dogs. Ten normal dogs weighing 7.6–13.0 kg (median 9.8 kg) were recruited. All dogs were considered normal based on complete blood count, serum chemistry profile, ultrasound examination, and percutaneous radiographic cholecystography. Percutaneous contrast ultrasound‐guided cholecystography was performed using 0.5 ml of commercially available contrast agent and two conventional ultrasound machines for simultaneous scanning at two different locations. Two observers independently evaluated the time to initial detection of contrast in the proximal duodenum and duration of contrast enhancement via visual monitoring. Dynamic contrast enhancement was calculated using time‐intensity curves. Mean (±SD) and median (range) of time to initial detection were 8.60 s (± 3.35) and 8.0 s (2.0–11.0), respectively, and mean and median duration were 50.45 s (±23.24) and 53.0 s (20.0 – 70.0), respectively. Mean, median, and range of peak intensity were 114.1 mean pixel value (MPV) (SD ± 30.7), 109.2 MPV, and 79.7–166.7, respectively, and mean, median, and range of time to peak intensity were 26.1 s (SD ± 7.1 s), 24.0 s, and 19.0–41.0 s, respectively. Findings indicated that percutaneous contrast ultrasound‐guided cholecystography is a feasible technique for detecting and quantifying patency of the bile duct in normal dogs. Future studies are needed to assess the diagnostic utility of this technique for dogs with biliary obstruction.  相似文献   
69.
70.
Owing to unique structure and characteristic of carbon nanotubes, much more are attracted attentions since they were discovered .In recent years, carbon nanotubes have been successfully synthesized by various methods. Especially, highly aligned carbon nanotubes were grown by chemical vapor deposition (CVD). In the work, it is studied that different thickness of catalyst affects the diameters of carbon nanotubes. Carbon nanotubes were grown on silicon substrate coated with different thick NiFe films by bias-enhanced hot filament chemical vapor deposition and their growth was investigated by scanning electron microscopy,Onset of analyzing of deformation of different thick catalyst films during heating the filament. The results indicate that catalyst particles encapsulate the top ends of carbon nanotubes, and that the catalyst thickness greatly affects the diameters of carbon nanotubes, which increas with increment of the thickness of NiFe films.  相似文献   
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