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81.
82.
This study was undertaken to compare the levels of ascorbic acid, vitamin C, flavonoids, nitrate, and oxalate in 27 spinach varieties grown in certified organic and conventional cropping systems. Liquid chromatography-electrospray ionization-tandem mass spectrometry (LC-(ESI)MS/MS) of methanolic extracts of spinach demonstrated 17 flavonoids, including glucuronides and acylated di- and triglycosides of methylated and methylenedioxyderivatives of 6-oxygenated flavonoids. The mean levels of ascorbic acid and flavonoids were significantly (p < 0.001) higher in the organically grown [40.48 ± 6.16 and 2.83 ± 0.03 mg/kg of fresh weight (FW)] spinach compared to the conventionally grown spinach (25.75 ± 6.12 and 2.27 ± 0.02 mg/kg of FW). Conversely, the mean levels of nitrate were significantly (p < 0.001) higher in the conventionally grown spinach compared to the organically grown spinach. No significant effects were observed in the oxalate content of spinach from either production system. The levels of nitrate correlated negatively with those of ascorbic acid, vitamin C, and total flavonoids and showed a positive correlation with the oxalate content. These results suggest that organic cropping systems result in spinach with lower levels of nitrates and higher levels of flavonoids and ascorbic acid.  相似文献   
83.
The feasibility of using kiwifruit protease as a new cosmetic material for human hair care was investigated. The effectiveness of the kiwifruit protease treatment was assessed by optical microscope examination, amino acid analysis, tensile strength changes, and dyeability test. The activated kiwifruit protease removed impurities and dirt from the hair surface without severe changes in mechanical properties. The total amino acid content of the hair samples decreased as the duration of protease treatment increased and as the treatment temperature increased. The kiwifruit protease treatment also enhanced dye uptake due to the improvement in dye accessibility to the hair via the cell membrane complex.  相似文献   
84.
85.
In humans, steroid 5α-reductase is involved in the development of benign prostatic hyperplasia (BPH). We tested the steroid 5α-reductase inhibitory activity of the 70% acetone extract of woody plants. The tannin polymer prepared from the 70% acetone extract showed the highest steroid 5α-reductase inhibitory activity. Furthermore, the steroid 5α-reductase inhibitory activity of tannins was not affected by the addition of superoxide dismutase or catalase. It was concluded that the steroid 5α-reductase inhibitory activity of condensed tannin was caused by binding to the steroid 5α-reductase, rather than from the peroxide/superoxide produced by tannins. The tannins, prepared from tree barks, with potential for steroid 5α-reductase inhibitory activity might be advantageous in therapy for steroid 5α-reductase diseases such as BPH or prostate cancer. Part of this report was presented at the 54th Annual Meeting of the Japan Wood Research Society, Sapporo, August 2004  相似文献   
86.
Insulinoma is a functional, insulin‐secreting tumor, arising from the beta islet cells of the pancreas. It is one of the most common neoplasms in ferrets and has been associated with clinical signs of hypoglycemia, such as ptyalism, pawing at the mouth, seizures, lethargy, and coma. The ultrasonographic features of insulinoma in ferrets have not been previously reported. The purpose of this retrospective case series study was to describe the ultrasonographic features of confirmed insulinoma in a group of ferrets. Inclusion criteria were abdominal ultrasound examination and histological confirmed insulinoma by surgical biopsy. Six ferrets met the inclusion criteria, all of which had multiple hypoglycemic episodes. Ultrasonographic images were reviewed and the characteristics of the pancreatic nodules were recorded. Twenty‐eight pancreatic nodules were observed in the six ferrets and were primarily hypoechoic (89.3%, 25/28) and homogenous (46.4%, 13/28) with a smooth margin (78.6%, 22/28). The distribution of the pancreatic nodules was 46.4% in the left lobe, 50% in the right lobe, and 3.6% in the body of the pancreas. The sizes of the pancreatic nodules varied from 1.5 × 1.5 to 4.1 × 5.6 mm. All of the pancreatic nodules removed from surgery were histopathologically confirmed as insulinoma. The findings indicated that insulinoma in ferrets could be detected through ultrasonography, which may facilitate diagnosis and preoperative surgical planning.  相似文献   
87.
Relaxin‐like factor (RLF), also known as insulin‐like factor 3 (INSL3), is produced by testicular Leydig cells, but its specific receptor LGR8 (leucine‐rich repeat family of G‐protein‐coupled receptor 8) has not been identified in goats. This study aimed to identify complementary DNA (cDNA) sequences of goat LGR8, and characterize the expression of both RLF and LGR8 in goat testes by RT‐PCR and immunohistochemistry. Testes were collected from immature (3‐month‐old) and mature (24‐month‐old) Saanen goats, and partial cDNA sequences of the goat homologue of human LGR8 were identified. The sequence encoded a reduced peptide sequence of 167 amino acids, which corresponded to transmembrane regions 2 through 5, followed by the beginning of intracellular loop 3 of human LGR8. Expression of both LGR8 and RLF genes was drastically increased in mature testes compared with immature ones. Although RLF protein was restricted to Leydig cells, LGR8 protein was detected in both Leydig cells and seminiferous epithelial cells (possibly germ cells and Sertoli cells). These results reveal a possible existence of the RLF‐LGR8 ligand‐receptor system within the goat testis, suggesting that RLF may play a role in testicular function through LGR8 on Leydig cells and seminiferous epithelial cells in an autocrine and/or paracrine manner.  相似文献   
88.
89.
The synthesis of a series of phthalimide based azo disperse dyes and their spectral properties were investigated. The azo dyes containing phthalimide and N-methyl phthalimide structure in diazo component were synthesized in order to compare their spectral properties. The synthesized dyes developed the color of yellow to violet and the N-substitution of the phthalimide gave a bathochromic effect on the color change. Most of the synthesized dyes exhibit negative solvatochromism so that the absorption band of dyes moves toward shorter wavelengths as the polarity of the solvent increases. In the case of halochromic effect, the bathochromic shift decreased steadily with the general electron donating capacity of the substituents in the coupling component, and became negative especially when more powerful electron donating groups are present in the coupling components ring.  相似文献   
90.
Novel regenerated cellulose material which was prepared from cellulose acetate fiber through the hydrolysis of acetyl groups have been developed by an environmentally friendly process without emitting toxic substances in addition to be at low production cost. They have composite crystalline structure constituted of cellulose II and cellulose IV. Also, they show a lamellar morphology with an increased amorphous region, as compared to conventional regenerated cellulose such as viscose rayon and cupra rayon. Our data obtained by several independent methods demonstrated that the adsorption properties of cellulose fibers depend predominantly on the amorphous region.  相似文献   
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