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31.
Karin Sorenmo Marissa Samluk Craig Clifford Jennifer Baez Beth Overley Katherine Skorupski Karen Oberthaler Jeffrey Barrett Tom Van Winkle Gabriela Seiler Robert Poppenga Frances Shofer 《Veterinary and comparative oncology》2005,3(1):55-56
Introduction: Canine hemangiosarcoma (HSA) is a fatal malignancy and most dogs die within 6–8 months of diagnosis. The spleen is a common primary site, representing 50% of all cases. These dogs typically present with clinical signs due to tumor rupture and intra‐abdominal dissemination; the abdomen is also the main site of disease progression when these patients fail. Direct delivery of chemotherapy into the abdominal cavity may therefore be a rational approach in this malignancy.
Methods: 14 dogs with stage 2 or 3 splenic HSA were recruited. Doxil at a dose of 1 mg/kg was diluted in saline and administered via ultrasound‐guidance into the abdominal cavity. The dogs were scheduled to receive 4 treatments every 3 weeks. Samples of plasma and abdominal fluid were collected for pharmacokinetic analysis. All dogs were monitored for recurrence and complete necropsies were requested at death.
Results: 8 dogs with stage 3 and 6 dogs with stage 2 HSA were enrolled. All 14 dogs have died, 12/14 due to tumor and 2 from other causes. There was no difference in median survival days between stages (stage 2: 244, stage 3: 125, p = .22). All 12 dogs that died due to tumor‐related causes failed with intra‐abdominal recurrence. Necropsies showed that the dogs in this study had relatively fewer extra‐abdominal metastasis compared to dogs treated with systemic chemotherapy. Pk analysis showed detectable plasma doxorubicin 1 and 2 weeks after treatment.
Conclusion: Direct abdominal administration of Doxil did not prevent intra‐abdominal recurrence; however, it appeared to provide effective systemic coverage. 相似文献
Methods: 14 dogs with stage 2 or 3 splenic HSA were recruited. Doxil at a dose of 1 mg/kg was diluted in saline and administered via ultrasound‐guidance into the abdominal cavity. The dogs were scheduled to receive 4 treatments every 3 weeks. Samples of plasma and abdominal fluid were collected for pharmacokinetic analysis. All dogs were monitored for recurrence and complete necropsies were requested at death.
Results: 8 dogs with stage 3 and 6 dogs with stage 2 HSA were enrolled. All 14 dogs have died, 12/14 due to tumor and 2 from other causes. There was no difference in median survival days between stages (stage 2: 244, stage 3: 125, p = .22). All 12 dogs that died due to tumor‐related causes failed with intra‐abdominal recurrence. Necropsies showed that the dogs in this study had relatively fewer extra‐abdominal metastasis compared to dogs treated with systemic chemotherapy. Pk analysis showed detectable plasma doxorubicin 1 and 2 weeks after treatment.
Conclusion: Direct abdominal administration of Doxil did not prevent intra‐abdominal recurrence; however, it appeared to provide effective systemic coverage. 相似文献
32.
C. A. Clifford E. S. Pretorius C. Weisse E. S. Siegelman K. U. Sorenmo K. Skorupski K. Drobatz K. E. Burgess R. M. Fred E. N. Glass M. Murray J. R. Solomon 《Veterinary and comparative oncology》2005,3(1):37-38
Introduction: Splenic lesions are a common finding in veterinary medicine and typically 1/2 to 2/3 of these lesions are malignant. Due to the limited accuracy of ultrasound, unnecessary exploratory surgeries/biopsies may be performed for benign lesions and treatment may be delayed for malignant ones. Splenic lesions are rare in people. MR imaging, with its inherently high soft tissue contrast, is efficacious in imaging the human spleen. We have previously demonstrated the efficacy of MRI to differentiate canine hepatic lesions. In that study 8 splenic lesions were all accurately characterized. This current study represents a further evaluation of splenic lesions.
Methods: In this prospective study, 27 dogs with splenic lesions were accrued. Histopathological/cytological confirmation of lesions occurred either before or shortly after imaging. MRI clinicians were blinded to histopathology results. MR (General Electric, 1.5 Tesla) images using a variety of sequences were obtained before and after intravenous administration of gadolinium.
Results: 32 lesions (9 malignant, 23 benign) were evaluated in 27 dogs. Lesions were confirmed via histopathology (n = 20) or cytology (n = 12). Benign lesions included, EMH (n = 7), hematoma/hemorrhage (n = 5), lymphoid hyperplasia (n = 9), and hemangioma (n = 2). Malignant lesions included anaplastic sarcoma (n = 3), malignant histiocytosis (n = 2), hemangiosarcoma (n = 2), plasma cell tumor (n = 1) and adenocarcinoma (n = 1). The overall accuracy in differentiating benign from malignant lesions was 88%(29/32 lesions). The overall sensitivity and specificity were 100%(95% CI, 66–100) and 87%(95% CI 66–97).
Conclusions: Based upon these results, MRI is both sensitive and specific in distinguishing between malignant and benign splenic lesions. 相似文献
Methods: In this prospective study, 27 dogs with splenic lesions were accrued. Histopathological/cytological confirmation of lesions occurred either before or shortly after imaging. MRI clinicians were blinded to histopathology results. MR (General Electric, 1.5 Tesla) images using a variety of sequences were obtained before and after intravenous administration of gadolinium.
Results: 32 lesions (9 malignant, 23 benign) were evaluated in 27 dogs. Lesions were confirmed via histopathology (n = 20) or cytology (n = 12). Benign lesions included, EMH (n = 7), hematoma/hemorrhage (n = 5), lymphoid hyperplasia (n = 9), and hemangioma (n = 2). Malignant lesions included anaplastic sarcoma (n = 3), malignant histiocytosis (n = 2), hemangiosarcoma (n = 2), plasma cell tumor (n = 1) and adenocarcinoma (n = 1). The overall accuracy in differentiating benign from malignant lesions was 88%(29/32 lesions). The overall sensitivity and specificity were 100%(95% CI, 66–100) and 87%(95% CI 66–97).
Conclusions: Based upon these results, MRI is both sensitive and specific in distinguishing between malignant and benign splenic lesions. 相似文献
33.
Clifford CA Hughes D Beal MW Henry CJ Drobatz KJ Sorenmo KU 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2002,16(2):164-168
Vascular endothelial growth factor (VEGF) has potent angiogenic, mitogenic, and vascular permeability enhancing properties specific for endothelial cells. VEGF is present in high concentrations in inflammatory and neoplastic body cavity effusions and has been implicated in the pathogenesis of neoplastic and inflammatory effusion formation. In this study, VEGF was quantitated by solid-phase enzyme-linked immunoadsorbent assay (ELISA) in samples of pericardial, pleural, and peritoneal effusions (N = 38) from dogs (N = 35) with neoplastic and non-neoplastic diseases. VEGF was detected in 37 of 38 effusions (median, 754; range, 18-3,669 pg/mL) and was present in much higher concentrations than in previously established normal concentrations for canine plasma (median, < 1 pg/mL; range, < 1-18 pg/mL) or in those previously noted in the plasma of dogs with hemangiosarcoma (HSA; median, 17 pg/mL; range, < 1-67 pg/mL). In 4 dogs with HSA, the concurrent plasma VEGF concentration was much lower than in the abdominal effusion (P = .029). No significant correlation was demonstrated between VEGF effusion concentration and effusion total protein content or nucleated cell count. Mean VEGF concentrations were significantly higher in pericardial (median, 3,533; range, 709-3,669 pg/mL) and pleural effusions (median, 3,144; range, 0-3,663 pg/mL) compared to peritoneal effusions (median, 288; range, 18-2,607 pg/mL; P < .05). There was no marked difference demonstrated between effusions associated with malignant and nonmalignant diseases. Further studies are necessary to elucidate the role of VEGF in body cavity effusion formation in dogs. 相似文献
34.
环境对玉米杂交种品质性状的影响研究 总被引:3,自引:1,他引:3
以河南省生产上主要推广的15个玉米品种为材料,采用近红外光谱技术,分析了在8个不同生态环境下粗蛋白、粗淀粉、粗脂肪和赖氨酸4个玉米品质性状。结果表明:各性状在品种间、地点间和品种与地点互作间的差异均达到极显著水平。在15个品种中,HE-1、HE-2、豫单2001和豫单2002粗蛋白含量高于11%以上,赖氨酸含量高于0.35%,可作为高蛋白、高赖氨酸优质饲用专用玉米品种;郑单958、浚单20、洛玉1号和郑单18粗淀粉含量在72%以上,可将作为高淀粉工业加工专用玉米品种;HE-1、HE-2的粗脂肪含量在7.5%以上,可将它们作为高油工业加工和优质饲用专用玉米品种。驻马店、郑州和洛阳适宜高蛋白、高赖氨酸优质饲用专用玉米品种的种植;商丘、安阳和周口适宜高淀粉工业加工专用玉米品种的种植;商丘、新乡和郑州适宜高油专用玉米品种的种植。 相似文献
35.
玉米和狗尾草光周期敏感性的比较研究 总被引:1,自引:0,他引:1
光周期是影响植物生长发育的关键因素之一。玉米和狗尾草都是短日照禾本科植物,且都具有光周期敏感性。对玉米和狗尾草的光周期敏感性比较研究,探索易于研究的狗尾草光周期敏感性机理,借以解析玉米光周期敏感性反应的机理。以玉米自交系CML288、黄早四和狗尾草自交系A10为材料,研究在长日照、短日照和在不同生育时期长短日照相互挪移处理下的光周期反应。结果表明,玉米和狗尾草在长日照条件下都表现出营养生长旺盛和生育期延迟,二者在长日照条件下的光周期敏感阶段都比短日照条件下的光周期敏感阶段长;玉米在进入光周期敏感期之前有一段时间的光周期钝感期,而狗尾草从发芽出苗就直接进入光周期敏感期。两个光周期敏感程度不同的玉米自交系比较,光周期敏感自交系CML288比光周期相对不敏感自交系黄早四的光周期敏感阶段长。 相似文献
36.
37.
玉米光周期反应及一个相关基因的克隆 总被引:9,自引:0,他引:9
【目的】研究玉米的光周期反应,克隆出玉米中的EMF同源基因并研究其表达模式。【方法】以热带玉米自交系CML288和温带玉米自交系黄早四为材料,研究了它们在9 h和15 h光周期处理后的反应和热带自交系CML288在不同时期两种日照挪动处理下的光周期反应。通过RT-PCR法克隆到一个玉米上的EMF同源基因,并检测了该基因在经过不同光周期处理的自交系CML288、黄早四及其F1的不同生长时期茎尖中的表达。【结果】 CML288对光周期的反应非常敏感,黄早四相对不敏感。CML288在短日照条件下7片叶时期是光周期反应的敏感时期,在长日照条件下9片叶时期是光周期反应的敏感时期。推测新克隆的cDNA序列含有完整的1 881bp的开放阅读框,编码一条约71kD的多肽,包含626个氨基酸残基,编码的蛋白质有一个C2H2型锌指结构区,两个核定位信号区和一个酸性区,可能是DAN结合蛋白,Northern杂交显示,其在茎尖和叶片中均有表达。经不同光周期处理后,该基因在2个自交系及F1不同生长时期茎尖中的表达情况不同。【结论】克隆到的基因其功能可能与促进营养生长和抑制生殖生长有关。 相似文献
38.
转pepc基因水稻的选育 总被引:13,自引:2,他引:13
通过基因工程 ,将玉米的磷酸烯醇式丙酮酸羧化酶 (pepc)基因导入水稻品种“Kitaake” ,获得高表达的转pepc基因水稻 ,系统选育后 ,获得第 7代稳定种质。转pepc基因水稻的PEPC活性比原种高 2 4倍 ,净光合速率比原种高 5 0 %。以第 7代稳定转基因材料作父本 ,与水稻不育系“培矮 64S”、“2 9130S”、“70 0 1S”以及恢复系“5 12 9”、“Y910 7”、“H9195”、“双九A”和“437”进行杂交 ,获得 80 5株后代材料 ,并从中鉴定出 47株高PEPC活性和高光合效率的植株。这些植株的PEPC活性和净光合速率 (Pn)均高于母本 ,且Pn与PEPC活性呈正相关 ,r=0 666 0 。证明通过基因工程与杂交相结合的方法 ,可将转pepc基因水稻的高光效特性传递到杂种稻的不育系和恢复系中 相似文献
39.
C. J. McNeill B. Overley F. S. Shofer M. S. Kent C. A. Clifford M. Samluk S. Haney T. J. Van Winkle K. U. Sorenmo 《Veterinary and comparative oncology》2007,5(2):90-98
The purpose of this retrospective study was to compare Rottweilers diagnosed with osteosarcoma (OSA) with other breeds to determine whether Rottweilers experienced a more aggressive form of the disease. Two hundred and fifty‐eight dogs were evaluated (102 clinical and 156 necropsy cases). In the necropsy population, Rottweilers had a younger mean age at death (7.3 versus 9 years, P= 0.006). There were no significant differences between Rottweilers and other breeds in age at diagnosis, median disease‐free interval or survival time. However, Rottweilers were more likely to have metastasis to the brain (7 versus 0%, P= 0.03). These results suggest that OSA in Rottweilers may have a different biological behaviour, but this study did not confirm that these differences were associated with a worse outcome. 相似文献
40.
Sensitivity and specificity of methods of assessing the regional lymph nodes for evidence of metastasis in dogs and cats with solid tumors 总被引:1,自引:0,他引:1
Langenbach A McManus PM Hendrick MJ Shofer FS Sorenmo KU 《Journal of the American Veterinary Medical Association》2001,218(9):1424-1428
OBJECTIVE: To determine sensitivity and specificity of physical examination, fine-needle aspiration, and needle core biopsy of the regional lymph nodes for evidence of metastasis in dogs and cats with solid tumors. DESIGN: Case series. ANIMALS: 37 dogs and 7 cats. PROCEDURE: Regional lymph nodes were evaluated by means of physical examination (palpation), fine-needle aspiration, and needle core biopsy. Results were compared with results of histologic examination of the entire lymph node, the current standard. RESULTS: Tumors included 18 sarcomas, 16 carcinomas, 7 mast cell tumors, and 3 other tumors. Carcinomas were more likely to have metastasized to the regional lymph node (7/16 animals) than were sarcomas (2/18). Sensitivity and specificity of physical examination were 60 and 72%, respectively. Sensitivity and specificity of cytologic examination of fine-needle aspirates were 100 and 96%, respectively. Sensitivity and specificity of histologic examination of needle core biopsy specimens were 64 and 96%, respectively. CONCLUSIONS AND CLINICAL RELEVANCE: Results suggested that fine-needle aspiration may be a sensitive and specific method of evaluating the regional lymph nodes in dogs and cats with solid tumors, because results correlated well with results of histologic examination of the entire lymph node. Physical examination alone was not a reliable method and should not be used to decide whether to aspirate or biopsy the regional lymph nodes. 相似文献