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91.
棉酚旋光体柱前衍生化-HPLC分析与4个栽培棉种之间棉酚含量比较 总被引:2,自引:0,他引:2
采用2%D-氨基丙醇+10%冰醋酸+88%乙腈作为棉酚提取和衍生化试剂对消旋棉酚和棉花样品进行热衍生化处理,用C18色谱柱和乙腈流动相进行高效液相色谱分析。该方法色谱结果表现为主峰清晰而杂峰少,左右旋棉酚出峰时间相差7 min,实验精度良好。用该方法对4个栽培种的25份材料的种仁和幼苗的根、茎、叶的左右旋棉酚含量进行了系统的检测。结果表明,海岛棉的种子和根系的总棉酚含量最高,其次是陆地棉;2个二倍体栽培棉种的种子和根系的总棉酚显著低于四倍体棉种,而2个二倍体栽培棉种的叶片总棉酚含量显著高于四倍体棉种。大多参试材料的种子和幼苗各部位的左右旋棉酚含量均有差异,其中海岛棉的左旋棉酚含量略高于右旋棉酚,陆地棉的右旋棉酚含量略高于左旋棉酚,而2个二倍体棉种的左旋棉酚只占总棉酚的1/3。无色素腺体棉的种仁和叶片中总棉酚含量极低,并以左旋棉酚为主,其种仁中只有左旋棉酚而无右旋棉酚;茎秆中总棉酚含量以及左右旋棉酚比例与一般有色素腺体常规棉相似,但根系中的总棉酚含量显著高于对应的有色素腺体棉,却以右旋棉酚为主。 相似文献
92.
ASSESSMENT OF SENTINEL LYMPH NODE METASTASIS IN CANINE MAMMARY GLAND TUMORS USING COMPUTED TOMOGRAPHIC INDIRECT LYMPHOGRAPHY 下载免费PDF全文
Christina Soultani Michail N. Patsikas Maria Karayannopoulou Samuel Jakovljevic Ioannis Chryssogonidis Lysimachos Papazoglou Nikolaos Papaioannou Paraskevi Papadopoulou Kyriaki Pavlidou Georgia M. Ilia Dimitrios G. Kaitzis Tatiana M. Ilia 《Veterinary radiology & ultrasound》2017,58(2):186-196
In the staging process of the breast cancer, demonstrating metastasis of the sentinel lymph node (SLN) has an important prognostic value, in both humans and animals. The aim of this prospective case‐control study was to determine the diagnostic value of computed tomographic indirect lymphography (CT‐LG) for detecting SLN metastasis in dogs with mammary cancer. Thirty‐three female dogs with tumors in the abdominal and inguinal mammary glands were prospectively selected and subjected to CT‐LG, 1 and 5 min after injection of 1 ml of contrast agent (iopamidol) in the subareolar tissue of the neoplastic and the contralateral normal mammary glands. The pattern of postcontrast opacification, degree of postcontrast enhancement, and size and shape were assessed in 65 SLNs in total and were correlated with histopathological findings. The absence of opacification or heterogeneous opacification 1 min after contrast medium injection showed the highest sensitivity, specificity, and accuracy (93%, 100%, and 98.4%, respectively). In images taken 1 min after injection, an absolute density value lower than 444 Hounsfield units (HU) in the center of the SLN also provided significant sensitivity and specificity (93.8% and 75%, respectively). The size and shape of the SLN (maximum and minimum diameter, maximum/minimum diameter ratio, maximum diameter/height of fifth thoracic vertebral body ratio) showed the lowest sensitivity and specificity. Results of this study support the hypothesis that CT‐LG could help in the assessment of SLN metastasis in cases of mammary gland tumors in dogs. 相似文献
93.
94.
Development of high-gossypol cotton plants with low-gossypol seeds using trispecies bridge crosses and in vitro culture of seed embryos 总被引:3,自引:1,他引:2
The objective of this work is to develop an upland cotton, Gossypium hirsutum L. [2n = 4x =52, 2(AD)h], having a reduced level
of gossypol in the seeds for food and feed uses, and a high level of gossypol in the remaining organs to limit pest incidence.
Using G. sturtianum Willis (2n = 2x = 26, 2C1) as donor and G. thurberi Torado (2n = 2x = 26, 2D1) or G. raimondii Ulbrich
(2n = 2x = 26, 2D5) as bridge species, two trispecies hybrids G. thurberi– G. sturtianum– G. hirsutum and G. hirsutum– G.
raimondii– G. sturtianum were synthesized. Both trispecies hybrids were male sterile. Recurrent backcrossing to G. hirsutum
as pollinator and selfing of the second backcross (BC) progenies resulted in seeds which were rescued by in vitro culture.
In total, 1208 flowers of the trispecies hybrids and their BC progenies yielded 192 seed embryos from which 62 plants were
obtained. Cytogenetic analyses indicated a relatively high frequency of chromosome pairing and chiasmata. The gland levels
in backcross seeds ranged from glandless seeds to normally glanded seeds. All vegetative parts of those hybrids were glanded,
but a wide range of variability for gland density was observed on leaf, stem, bract and calyx. Plants derived from seeds having
a reduced level of gossypol constitute very interesting germplasm to develop a cultivated glanded cotton with low-gossypol
seeds.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
95.
Qing Liu Jie Yu Min Li Ruitao Zhang Peng Gao Guanglei Cong Daiyong Cui Chuanliang Ji Shenming Zeng 《Reproduction in domestic animals》2021,56(2):301-312
The purpose of this study was to analyse the effects of season, age, gonad and accessory sex glands on semen characteristics of jackass and to construct multivariate regression models to predict semen quality. In autumn, spring and summer, semen characteristics of 30 sexually mature donkeys (1,014 ejaculations) were analysed to investigate the effect of seasons on semen quality, and gonad and accessory sex gland parameters of 12 jackasses were measured immediately after ejaculation by ultrasonography to investigate the effect of seasons on reproductive organ size. Semen (598 ejaculates), gonad and accessory sex gland parameters of 40 jackasses aged between 3 and 7 years were analysed in autumn to investigate the effects of age and reproductive organ size on semen quality and to construct multivariate models. To verify the accuracy of the models, semen (476 ejaculates), gonad and accessory sex gland parameters of 20 jackasses were measured from March to June. Results revealed that semen, gonad and accessory sex gland parameters were not affected by season and age. Progressive motility (PM) was positively correlated with long axis of the spermatic cord (LASC) and negatively correlated with percentages of sperm abnormality (PSA). Total sperm count (TSC) was positively correlated with testis circumferences (TC) and cross-sectional area of cauda epididymis (CSACE). TC, CSACE, LASC and PSA were included into multivariate models to predict PM, TSC and functional sperm count (FSC) in 20 jackasses (PM = 72.332 + 0.428 LASC − 0.441 PSA; TSC = −169.929 + 8.728 TC + 0.253 CSACE; FSC = −206.645 + 8.788 TC + 0.258 CSACE). The predicted and observed values corresponded well. In conclusion, the tested models can be used for predicting semen quality of donkey. 相似文献
96.
《African Zoology》2013,48(4):327-330
Despite its cryptic habitat and habits, light and transmission electron microscopy has revealed that like many other siphonariids Siphonaria compressa, the smallest species of this genus, possesses lateral pedal glands. The pear-shaped glands (about 120 µm long×70 µm maximum diameter) open via a pore, and are multicellular with three types of secretory cell that surround a central lumen. The glands of this minute pulmonate limpet are similar in structure to its larger relatives, suggesting that they are defensive in function. 相似文献
97.
Laura Guerra John G. Stoffolano Maria Cristina Belardinelli Anna Maria Fausto 《Journal of insect science (Online)》2016,16(1)
Using a serotonin antibody and confocal microscopy, this study reports for the first time direct serotonergic innervation of the muscle sheath covering the secretory region of the salivary glands of adult tsetse fly, Glossina pallidipes Austen. Reports to date, however, note that up until this finding, dipteran species previously studied lack a muscle sheath covering of the secretory region of the salivary glands. Direct innervation of the salivary gland muscle sheath of tsetse would facilitate rapid deployment of saliva into the host, thus delaying a host response. Our results also suggest that the neuronal and abnormal pattern seen in viral infected glands by the Glossina pallidipes salivary gland hypertrophy virus (GpSGHV) is due to a compensatory increased branching of the neurons of the salivary glands, which is associated with the increased size of the salivary glands in viral infected flies. This study shows for the first time serotonin in the cell bodies of the brain and thoracico-abdominal ganglion in adult tsetse, G. pallidipes Austen (Diptera: Glossinidae). A hypothesis is proposed as to whether innervation of the muscle sheath covering of the secretory region of the salivary glands is present in brachyceran compared with nematoceran dipterans; and, a plea is made that more research is needed to develop a blood feeding model, similar to that in the blow flies, for elucidating the various mechanisms involved in production and deployment of saliva. 相似文献
98.
目的 观察柴芍乳癖颗粒对乳腺增生病兔模型乳腺组织B超声像及组织形态学的影响。方法 56只健康未孕新西兰雌兔,随机挑出10只为正常对照组,肌注生理盐水;46只为模型制备组,序贯肌注雌孕激素造模。2组均随机处死1只雌兔,观察病理切片确定造模成功后,将模型制备组剩下的45只兔再随机分为5组:模型对照组、乳癖散结颗粒组、柴芍乳癖颗粒低、中、高剂量组。6组兔每天分别予以生理盐水、乳癖散结颗粒(0.56 g/kg)、柴芍乳癖颗粒(0.47、0.94、1.88 g/kg)水溶液灌胃1次,连续3月。末次灌胃 24 h后麻醉,用B超机采集第2对乳房的声像图,处死后取第2对乳腺组织,HE染色观察组织形态学表现,计数乳腺小叶腺泡数、导管上皮细胞层数、腺泡腔直径。结果 柴芍乳癖颗粒能使模型兔乳腺组织低回声区缩小,内部回声强度减低,其中高剂量组最明显;与模型组相比,柴芍乳癖颗粒低、中、高剂量跟乳癖散结颗粒均可明显缩小腺泡腔直径(P<0.01),中、高剂量可以减少乳腺导管上皮细胞层数,低剂量还可减少乳腺小叶腺泡数(P<0.05)。结论 柴芍乳癖颗粒可以改善乳腺增生兔模型B超声像,减轻雌兔乳腺增生程度,治疗乳腺增生效果明显。 相似文献
99.
Characterization of dual enzyme resulted from bicistronic expression of two β-glucanases in porcine cells 下载免费PDF全文
ZHANG Xian-wei LI Zi-cong MENG Fan-ming WANG De-hua LIU De-wu HE Xiao-yan SUN Yue BAI Yin-shan WU Zhen-fang 《农业科学学报》2015,14(4):732-740
Many animal feed grains contain high β-glucan in the cell wall. Pigs do not secret β-glucanase to degrade the β-glucan in their feed. The indigestible β-glucan not only blocks the release of nutrients from the grain cell wall, but also increases the digesta viscosity in the gastrointestinal tract of pigs. Therefore, dietary β-glucan significantly inhibits nutrient digestion and absorption in pigs. Transgenic expression of β-glucanase in the digestive tract of pigs may offer a solution to solve this problem. In the current study, four arti?cial codon-optimized β-glucanases genes was prepared and expressed in porcine cells. Only pBgA and pEgx showed high activity in transfected pig kidney cells. To improve the pH range and pH stability of β-glucanase, the two β-glucanases, pBgA and pEgx, were co-expressed in pig kidney cells and salivary gland cells by Linker A3 or 2A peptide. The resulting dual enzymes of pBgA3pEg and pBg2ApEg showed significantly enlarged pH range and significantly increased pH stability, as compared to parental enzymes. These results provide useful data for future study on increasing the feed digestibility of pigs by transgenic expression of β-glucanase in their salivary glands. 相似文献
100.
【目的】对柞蚕雌蛾粘液腺的生长发育过程和组织结构特征进行研究,并分析其内容物成分,为阐明粘液腺分泌胶着物质的机理提供参考。【方法】通过解剖获得不同发育时期的粘液腺并制备组织石蜡切片,观察其形态特征及组织显微结构。【结果】随着发育阶段的推进,粘液腺形态呈现出逐渐增大趋势,至羽化前达最大。而粘液腺内容物的颜色亦发生了显著变化,由透明色逐渐变为深黑色。光学显微镜观察结果显示,粘液腺的分泌部和贮藏部横截面结构存在差异,前者具备分泌细胞的特征,而后者不具备。【结论】粘液腺的形态结构特征在不同发育时期及组织部位存在差异。 相似文献