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371.
This study is intended for finding out the optimal processing parameters for needle punching nonwoven fabrics in order to
work out its maximal strength. Taguchi method together with grey relational analysis is employed to resolve the problem as
regards multiple-quality optimization, and further discover the optimal combination of processing parameters for needle punching
nonwoven fabrics. Firstly, orthogonal array L18(21×37) is used to deal with the processing parameters that may exert influence over the manufacturing of needle punching nonwoven
fabrics. Then grey relational analysis is applied to resolve the deficiency of Taguchi method that focus on single quality
characteristic. Next, the response table of grey relational analysis is used to obtain the optimal combination of processing
parameters for multiple quality characteristics. In the current experiment quality characteristic refers to the tensile strength
and tear strength of the nonwoven fabrics. Additionally, signal-to-noise ratio (SN ratio) calculation and analysis of variance
(ANOVA) can be adopted to explore the experimental results. Through ANOVA, the significant factors that exert comparatively
significant influence over the quality characteristic of the needle punching nonwoven fabrics, that is, the control factors
are determined so that the quality characteristic of the needle punching nonwoven fabrics can be effectively controlled. Finally,
confirmation experiment is conducted within 95 % confidence interval to verify the experimental reliability and reproducibility. 相似文献
372.
Chun-Ming Lin Chian-Ren Jeng Shih-Hsuan Hsiao Chih-Cheng Chang Chen-Hsuan Liu Yi-Chieh Tsai Mi-Yuan Chia Victor Fei Pang 《Veterinary microbiology》2009,138(3-4):225-234
Taking advantage of the high sensitivity of polymerase chain reaction (PCR) and the cell-localizing ability of in situ hybridization (ISH), an indirect in situ PCR (ISPCR) method was developed for detecting the distribution of porcine circovirus type 2 (PCV2) in formalin-fixed and paraffin-embedded inguinal lymph nodes obtained from clinically healthy PCV2-carrier pigs and postweaning multisystemic wasting syndrome (PMWS)-affected pigs. Comparisons of the relative sensitivity of indirect ISPCR with other routinely used diagnostic methods for PCV2 indicated that nested PCR was the most sensitive method followed by indirect ISPCR, conventional PCR, ISH, and immunohistochemical (IHC) staining. Although indirect ISPCR, ISH, and IHC staining all revealed a similar signal distribution pattern of PCV2, using indirect ISPCR allowed specific amplification and detection of previously uneasily detected PCV2 signal than by routine ISH or IHC staining, particularly in those cells within the germinal center in clinically healthy PCV2-carrier pigs. Furthermore, six different PCV2 signal expression patterns in conjunction with the correlated lymphoid lesion stages were classified to describe the tissue morphological changes and viral infection. The result indicates that indirect ISPCR is a more effective, cell-based diagnostic tool with good specificity to detect limited PCV2 infection in formalin-fixed and paraffin-embedded tissue specimens and it would be a useful tool for further exploring the pathogenesis of PCV2 infection. 相似文献
373.
Tzu-Yin Lin Rachael Thomas Pei-Chien Tsai Matthew Breen Cheryl A. London 《Veterinary immunology and immunopathology》2009,127(1-2):114-124
Studies using the currently available malignant canine mast cell lines and bone marrow-derived cultured mast cells (BMCMCs) have provided an in-depth understanding of normal and neoplastic canine mast cell biology. However, many of the currently available malignant canine mast cell lines possess limitations, including loss of cell surface markers and inability to bind canine IgE. We have recently generated a novel mast cell line, CL1, from an 11-year-old spayed female Labrador retriever diagnosed with systemic mastocytosis and neoplastic effusion. The CL1 cells express KIT, Fc?RI, CD44, CD45, CD14, CD11a, CD11b and CD18 as well as chymase. Interestingly, these cells express wild-type KIT, with no evidence of autophosphorylation, but are able to proliferate independently without the addition of exogenous stem cell factor (SCF), KIT ligand. However, stimulation of CL1 cells with SCF induces KIT phosphorylation promoting cell proliferation. The CL1 cells retain functional properties of mast cells, degranulating in a dose-dependent manner in response to both IgE cross-linking and chemical stimulation. Lastly, cytogenetic evaluation revealed several recurrent tumor-associated chromosome copy number imbalances in the CL1 line. In summary, the CL1 cell line possesses phenotypic and functional properties similar to those found in canine BMCMCs, and will likely be a useful tool to study mast cell biology, factors regulating transformation of mast cells, cytogenetic abnormalities in mast cell tumors, and novel preclinical therapies. 相似文献
374.
375.
Steam distilled essential oil from the aerial parts of Pogostemon cablin was analyzed by gas chromatography-mass spectrometry (GC-MS). Forty one compounds were identified of which alpha-guaiene (20.62%) and alpha-bulnesene (16.18%) were major constituents. Furthermore, fractionation of the essential oil from P. cablin guided by inhibitory activity against PAF-induced platelet aggregation led to the isolation of the sesquiterpene, alpha-bulnesene. 相似文献
376.
377.
Measurements of either heartbeats or heart rate variability provide important information on metabolic changes and stress responses. In this study, we aimed to determine the suitable temperature conditions for maintaining product quality for post‐harvest processing of mud crab (Scylla serrata) through measuring cardiac performance. A bundle of implanted electrodes was used to record the electrocardiogram, from which the heart rate (HR) and heart rate variability (HRV) were derived to evaluate the physiological performances of the crabs under tying at different seawater temperatures. The lowest standard deviation of HR was detected at the seawater temperature of 18°C for the group of ascending temperatures and at 10°C for the group of descending temperatures. Lower HRV was detected at the range from 10 to 14°C. The results suggest that the temperature range of 14–18°C is suitable to reduce variability in heart rate and may decrease physiological stress. These conditions might help maintain the quality of live crabs during post‐harvest processing and transportation. 相似文献
378.
Japonica (Tainung 67 [TNu67]) and waxy (Taichung 70 [TCW70]) rice, normal and waxy corn, and cross-linked waxy rice and corn starches were used in an investigation of the influence of the granular structure on the pasting behavior of starch, using small amplitude oscillatory rheometry. Both normal corn and normal rice (TNu67) starches had the highest storage moduli (G′), followed by their cross-linked versions; native waxy corn and rice starches had the lowest. Native waxy starches showed paste characteristics (G′ < 500 Pa; tan δ > 0.2) at concentrations of up to 35%. However, cross-linked waxy starches exhibited gel behavior at 10% concentration (cross-linked TCW70) or higher (cross-linked waxy corn starch). The degrees of swelling power were in the order: TCW70 > native waxy corn > TNu67 ≅ cross-linked TCW70 ≅ normal corn ≅ cross-linked waxy corn starches. Solubilities were in the order: normal corn > TNu67 > native waxy > cross-linked waxy starches. The addition of 2% purified amylose from indica rice (Kaohsiung Sen 7) did not induce gelation of waxy corn starch. Swelling powers of normal corn, TNu67, and crosslinked waxy starches were similar, but normal corn and TNu67 had much higher G′ value. Such results implied that the formation of gel structure was governed by the rigidity of swollen granules and that the hot-water soluble component could strengthen the elasticity of the starch gel or paste. 相似文献