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21.
采用基于Contex-M3架构的STM32系列单片机作为主控芯片,在uvision4环境中以C语言设计驱动系统软件;通过设计制作的系统硬件电路板,在新能源汽车电池散热风扇上进行空载试验,测试驱动系统对散热风扇的控制效果,并比较求反正切和锁相环2种转子位置信息估算方法的差异性. 相似文献
22.
In trace metal (TM)-contaminated agricultural soils, management of TM availability is important for safe crop production. In addition, maintenance or improvement of soil quality is vital for sustainable crop cultivation. Decreased TM phytoavailability and increased soil quality can be achieved by the application of various immobilizing agents to soil, which can supply both macronutrients and organic matter. This study investigated the long-term influences of four common immobilizing agents on so... 相似文献
23.
K. LEANN KUEBELBECK DVM DONNIE E. SLONE DVM MS Diplomate ACVS KIM A. MAY DVM 《Veterinary surgery : VS》1998,27(2):132-137
Objective —To determine if omentectomy would decrease the frequency of postoperative intraabdominal adhesions. Study Design —Retrospective study. Animals or Sample Population—44 horses that had either two ventral median celiotomies or a ventral median celiotomy and a necropsy more than 4 days later; 19 of these horses had their omentum removed at the initial surgery. Methods —Data retrieved from the records included location and type of intraabdominal adhesions; location of the surgical lesion; relationship of adhesions to the surgical lesion; surgical procedures; duration of initial surgery; time interval between procedures; age, gender, and breed of the horse; and clinical outcome. Fisher's exact test was used to evaluate the association between categorical explanatory and outcome variables. The effect of potential risk factors on the incidence rate of adhesion formation was estimated using a proportional hazards regression model. Results —Of 25 horses in the nonomentectomy group, 15 (60%) had postoperative adhesions that resulted in the need for a second surgical intervention, whereas of 19 horses that had omentectomy initially, only 4 (21%) had postoperative adhesions that required a second procedure. Rate of adhesion formation was higher in horses that did not have omentectomy initially (incidence ratio rate [IRR], 0.46; 90% confidence interval [CI], 0.18 to 1.19). At initial surgery, 24 horses had a small intestinal lesion, and 20 horses had a large intestinal lesion. Fifteen horses (63%) with small intestinal lesions subsequently developed adhesions compared with four horses (20%) with an initial large intestinal lesion (P= .006). At the second procedure, small intestine lesions were identified in 32 horses and large intestine lesions in 12 horses (1 horse had both small and large intestine lesions), and 1 horse had a gastric lesion. Adhesions were identified as the cause of colic signs in 19 (61%) horses with small intestinal lesions and in none of the horses with large intestine lesions. The frequency of adhesion development leading to colic associated with only the small intestine at the second surgery or necropsy was significantly greater (P= .001) than the frequency only in the large intestine. Conclusions —Omentectomy reduced the rate of postoperative adhesion formation. Adhesions are more likely to occur after small intestinal surgery and if they do occur likely involve the small intestine. Clinical Relevance —Omentectomy is a safe procedure and should be considered prophylactically for reduction of adhesion formation after abdominal surgery in horses. 相似文献
24.
To understand wood colonization by sapstain fungi and their potential biocontrol agents, it is necessary to differentiate these organisms directly on their natural substrates. In the present study the feasibility of transforming with the green fluorescent protein (GFP), the sapstain fungus Ophiostoma piceae and a potential biocontrol agent Cartapip®, an Ophiostoma piliferum albino strain was assessed. Transformants of the two fungal species were screened by polymerase chain reaction and Southern blot analyses. The GFP was expressed in spores, synnemata and mycelia of the transformants grown in artificial media or wood. The growth, pigmentation and wood colonization of the transformants were similar to that of the non‐transformants, suggesting that the presence of the gfp gene had no negative effect on the biology of the transformants. Using fluorescence and confocal microscopy, the GFP‐expressing fungi were easily differentiated from the wild‐type strains and other fungal species in wood, even 4 months after inoculation. The results show that the use of the GFP system is feasible to monitor Ophiostoma fungi in wood. 相似文献
25.
Toyokazu KOBAYASHI Hiroshi KOIE Arisa WATANABE Arisa INO Kazuya WATABE Mujo KIM Kiichi KANAYAMA Kazuya OTSUJI 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2015,77(4):503-506
We examined the effects of chicken egg hydrolysate (also known as “bone peptide” or BP)
on bone metabolism in 5- to 8-month-old orchidectomized dogs. The bone formation marker
serum bone alkaline phosphatase (BAP) and the bone resorption marker urine
deoxypyridinoline (DPD) were used as indicators to measure changes in bone metabolism. The
following results were observed that Serum BAP was higher in dogs fed BP-enriched food
throughout the clinical investigation. Serum BAP was statistically significantly higher in
dogs fed BP-enriched food than in dogs fed non-BP-enriched food at 2 months after
orchidectomy. This suggests that BP promoted bone formation immediately after
orchidectomy. 相似文献
26.
Ji-Yeong YEON Sung-Hun MIN Hyo-Jin PARK Jin-Woo KIM Yong-Hee LEE Soo-Yong PARK Pil-Soo JEONG Humdai PARK Dong-Seok LEE Sun-Uk KIM Kyu-Tae CHANG Deog-Bon KOO 《The Journal of reproduction and development》2015,61(2):81-89
Mitochondria are highly dynamic organelles that undergo constant fusion/fission as well as activities orchestrated by large dynamin-related GTPases. These dynamic mitochondrial processes influence mitochondrial morphology, size and function. Therefore, this study was conducted to evaluate the effects of mitochondrial fission inhibitor, mdivi-1, on developmental competence and mitochondrial function of porcine embryos and primary cells. Presumptive porcine embryos were cultured in PZM-3 medium supplemented with mdivi-1 (0, 10 and 50 μM) for 6 days. Porcine fibroblast cells were cultured in growth medium with mdivi-1 (0 and 50 μM) for 2 days. Our results showed that the rate of blastocyst production and cell growth in the mdivi-1 (50 μM) treated group was lower than that of the control group (P < 0.05). Moreover, loss of mitochondrial membrane potential in the mdivi-1 (50 μM) treated group was increased relative to the control group (P < 0.05). Subsequent evaluation
revealed that the intracellular levels of reactive oxygen species (ROS) and the apoptotic index were increased by mdivi-1 (50 μM) treatment (P < 0.05). Finally, the expression of mitochondrial fission-related protein (Drp 1) was lower in the embryos and cells in the mdivi-1-treated group than the control group. Taken together, these results indicate that mdivi-1 treatment may inhibit developmental competence and mitochondrial function in porcine embryos and primary cells. 相似文献
27.
Jin-Gu NO Mi-Kyung CHOI Dae-Jin KWON Jae Gyu YOO Byoung-Chul YANG Jin-Ki PARK Dong-Hoon KIM 《The Journal of reproduction and development》2015,61(2):90-98
Pretreatment of somatic cells with undifferentiated cell extracts, such as embryonic stem cells and mammalian oocytes, is an attractive alternative method for reprogramming control. The properties of induced pluripotent stem cells (iPSCs) are similar to those of embryonic stem cells; however, no studies have reported somatic cell nuclear reprogramming using iPSC extracts. Therefore, this study aimed to evaluate the effects of porcine iPSC extracts treatment on porcine ear fibroblasts and early development of porcine cloned embryos produced from porcine ear skin fibroblasts pretreated with the porcine iPSC extracts. The ChariotTM reagent system was used to deliver the iPSC extracts into cultured porcine ear skin fibroblasts. The iPSC extracts-treated cells (iPSC-treated cells) were cultured for 3 days and used for analyzing histone modification and somatic cell nuclear transfer. Compared to the results for nontreated cells, the trimethylation status of histone H3
lysine residue 9 (H3K9) in the iPSC-treated cells significantly decreased. The expression of Jmjd2b, the H3K9 trimethylation-specific demethylase gene, significantly increased in the iPSC-treated cells; conversely, the expression of the proapoptotic genes, Bax and p53, significantly decreased. When the iPSC-treated cells were transferred into enucleated porcine oocytes, no differences were observed in blastocyst development and total cell number in blastocysts compared with the results for control cells. However, H3K9 trimethylation of pronuclear-stage-cloned embryos significantly decreased in the iPSC-treated cells. Additionally, Bax and p53 gene expression in the blastocysts was significantly lower in iPSC-treated cells than in control cells. To our knowledge, this study is the first to show that an extracts of porcine iPSCs can affect histone modification and gene expression in porcine ear
skin fibroblasts and cloned embryos. 相似文献
28.
Asahi HORINAKA Yo-Han KIM Atsushi KIMURA Eiji IWAMOTO Tatsunori MASAKI Toshihiro ICHIJO Shigeru SATO 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2021,83(7):1098
We investigated changes in the predicted functions of the rumen bacterial community in Japanese Black beef cattle during fattening. Nine cattle were fed a high-concentrate diet during the early, middle, and late fattening stages consecutively (10–14, 15–22, and 23–30 months of age, respectively). The rumen fluid and solid samples collected at each stage were subjected to sequencing analyses. The sequencing results were clustered and classified into operational taxonomic units (OTUs). Representative sequences and a raw counting table for each OTU were submitted to the Piphillin website. The predicted functions were revealed by the Kyoto Encyclopedia of Genes and Genomes database as the ratio of the total sequence. In the early stage, “Biosynthesis of secondary metabolites” was significantly higher in the fluid fraction than in the solid fraction. “Two-component system” in the middle stage was significantly lower and “Purine metabolism” in the late stage was significantly higher in the fluid fraction than those in the solid fraction. The fluid fraction was significantly correlated with acetic acid, propionic acid, and bacterial metabolism, such as “Biosynthesis of secondary metabolites” and “Sugar metabolism.” Moreover, the solid fraction was correlated with “Purine metabolism” and “Biosynthesis of secondary metabolism”. These results suggest that the rumen bacterial community in Japanese Black beef cattle adapts to changes in rumen conditions by altering their functions in response to a long-term high-grain diet. 相似文献
29.