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161.
In the present study, we investigated the relationship between the temperature-humidity index (THI) and the conception rate of lactating dairy cows in southwestern Japan, one of the hottest areas of the country. We also investigated the relationship between measurement of the vaginal temperature of lactating dairy cows as their core body temperature at one-hour intervals for 25 consecutive days in hot (August-September, n=6) and cool (January-February, n=5) periods and their THI. Furthermore, we discussed the above relationship using these vaginal temperatures, the conception rates and the THI. As a result, when the conception rates from day 2 to 0 before AI were classified into day 2, 1 and 0 groups by the six maximum THI values in each group (mTHI; <61, 61-65, 66-70, 71-75, 76-80, >80), only the conception rate for the mTHI over 80 at 1 day before AI group was significantly lower (P<0.05) than the other groups. The conception rate for days 15 to 17, but not days 19 to 22 and 30 to 35, after AI in the cows that experienced average mTHI over 80 (amTHI>80) was significantly lower (P<0.05) than that of the cows that did not experience amTHI>80. There was a significant positive correlation (P<0.01) between the mTHI and the mean daily vaginal temperature, but not during the cool period. When the mTHI reached 69, the vaginal temperature started to increase. As for the relationship between the conception rates and vaginal temperatures for all mTHI classes, in the mTHI>80 at 1 day before AI group, the vaginal temperature increased by 0.6 C from 38.7 C, resulting in a reduction of 11.6% in the conception rate from 40.5%. In conclusion, these results suggest that one of the causes of the fall in conception rate of lactating dairy cows during the summer season in southwestern Japan may be an increase in their core body temperature with a higher mTHI than the critical mTHI of 69 at 1 day before AI.  相似文献   
162.
A 5-day-old hornless goat was referred with dysuria since birth. The scrotum was absent, and a small penis-like structure was seen below the perineal raphe. On the laparotomy, the testicles were found near the inguinal ring- and attached to a uterus-like structure. On histological analysis, the uterus-like structure was blind-end. Germ cells were absent in the testis. The karyotype of this goat was 60, XX and the SRY gene was absent. The goat was homozygous for a DNA deletion responsible for the Polled Intersex Syndrome (PIS). To the authors' knowledge, this is the first report as the clinical case of the PIS-/- goat with urethral atresia.  相似文献   
163.
We prepared a molecular photodiode system in which the photocurrent direction can be switched by choosing the wavelength of an irradiating light. The molecular system is composed of two types of helical peptides that carry different chromophores and have different directions of dipole moments when they are immobilized on gold. The mixed, self-assembled monolayer generated an anodic photocurrent when one of the two chromophores was photoexcited, whereas the photocurrent switched to being cathodic when the other chromophore was photoexcited. The opposite current response arises from the dipole moment of each helical peptide, which accelerates electron transfer in the same direction.  相似文献   
164.
The ability to incorporate individual atoms in a surface following predetermined arrangements may bring future atom-based technological enterprises closer to reality. Here, we report the assembling of complex atomic patterns at room temperature by the vertical interchange of atoms between the tip apex of an atomic force microscope and a semiconductor surface. At variance with previous methods, these manipulations were produced by exploring the repulsive part of the short-range chemical interaction between the closest tip-surface atoms. By using first-principles calculations, we clarified the basic mechanisms behind the vertical interchange of atoms, characterizing the key atomistic processes involved and estimating the magnitude of the energy barriers between the relevant atomic configurations that leads to these manipulations.  相似文献   
165.
Bifidobacterial plasmids reported so far are derived from a limited number of strains and plasmids of bifidobacterial type strains isolated from humans are unknown. We found that Bifidobacterium kashiwanohense JCM 15439 (type strain) isolated from a healthy infant contained two cryptic plasmids, designated pBBKW‐1 and pBBKW‐2. We determined and analyzed the complete sequences of both plasmids. pBBKW‐1 (7716 bp) was predicted to replicate by a rolling‐circle mechanism and encode six protein‐coding genes, two of which are putative replication proteins. pBBKW‐1 seems to be a cointegrate plasmid containing two copies of the plasmid pMG1 from Bifidobacterium longum. pBBKW‐2 (2920 bp) was predicted to encode six protein‐coding genes and be a theta‐type replicating plasmid, which has been reported to be more stable than a rolling circle‐type replicating plasmid frequently found in bifidobacteria. Our finding will provide new insights into safe recombinant plasmid constructions for humans.  相似文献   
166.
ABSTRACT:   The seasonal distribution, age, growth and reproductive biology of marbled sole Pleuronectes yokohamae (Günther) from Tokyo Bay, Japan were studied. A clear seasonal distribution trend was observed, with P. yokohamae limited to the south of the bay in summer and expanding almost throughout the bay in other seasons. The formation and dynamics of hypoxic areas in the bay limited the northward distribution of P. yokohamae in summer. Age was determined by counting growth rings on otoliths; maximum ages were found to be 5 years for males and 6 years for females. The mean back-calculated length for females at each estimated age was greater than that for males. Growth of males and females was shown by the von Bertalanffy growth equations. Reproductive biology was studied on the basis of gonadosomatic indices and histological sections of gonads. The spawning season lasted from November to March, peaking in December and January. Sixty per cent of males at 1 year and all males ≥ 2 years had mature testes, whereas 6.7% of females at 1 year, 58.3% of females at 2 years, and all females ≥ 3 years had attained maturity.  相似文献   
167.
The feasibility of using rainbow trout Oncorhynchus mykiss embryos as an expression system for proteins was investigated. For model proteins, we selected two goldfish gonadotropins (GTHs), follicle-stimulating hormone (FSH) and luteinizing hormone (LH). To produce single-chain goldfish FSH (scgfFSH) and LH (scgfLH), cDNAs encoding glycoprotein hormone (GP) α and FSHβ were fused in tandem, and cDNAs encoding GPα and LHβ were fused in tandem. The fused cDNAs were ligated with β-actin promoter, and microinjected into fertilized rainbow trout eggs. After 4-days incubation, the embryos were subjected to western blotting and in vitro bioassays. The recombinant proteins produced by the embryos were immunoreactive to antisera against goldfish GPα, N-glycosylated, and biologically active. We conclude that scgfFSH and scgfLH were successfully produced in transgenic rainbow trout.  相似文献   
168.
The present study was undertaken to investigate the distribution of Listonella anguillarum in the rearing water, fish and diets (rotifers) of Japanese flounder (Paralichthys olivaceus). A total of 793 isolates were obtained from the seed production environment of Japanese flounder and 175 out of them were identified as L. anguillarum by biochemical characterization, polymerase chain reaction (PCR) detection for VAH1 haemolysin gene and phylogenetic analysis of 16S ribosomal deoxyribonucleic acids (rDNA) sequences. These results strongly suggested that L. anguillarum is rapidly and accurately identified by the combination of incubation on thiosulphate–citrate–bile salt–sucrose agar at 35°C overnight and PCR detection for the VAH1 haemolysin gene. All flounder specimens and all rotifer samples harboured L. anguillarum at high densities of 6.9 × 103–6.3 × 105 colony forming units (CFU) g?1 and 1.5 × 104–2.3 × 106 CFU g?1, respectively, while as low as 5.0 × 100–2.0 × 101 CFU mL?1 of L. aguillarum were detected in only two of 11 seawater samples, even though no vibriosis occurred in larval and juvenile flounder of tanks. This fact strongly suggests that L. anguillarum is an inhabitant in the seed production environments of Japanese flounder.  相似文献   
169.
170.

Japanese star anise (Illicium anisatum L., JSA) is seriously damaged by a ringspot disease in Japan. Herein, to determine the causal agent using high-throughput sequencing, we discovered viral RNAs associated with JSA ringspot disease. We then determined the complete or near-complete nucleotide sequences of these RNAs using Sanger sequencing and RACE. The complementary strand of viral RNAs 1, 2, 3, 4, and 5 encoded a single protein, which shared sequence identity with P1 (RNA-dependent RNA polymerase), P2 (glycoprotein precursor), P3 (nucleocapsid protein), P4 (movement protein), and a protein with unknown function of emaraviruses (genus Emaravirus), respectively; however, the highest amino acid sequence identity for the P1–P5 proteins between JSARaV and known emaraviruses was 41.9%, 30.0%, 30.1%, 52.2%, and 38.0%, respectively, all of which were lower than the species demarcation criterion. Furthermore, RNA segments harbored conserved 12-nt terminal sequences at the 5′- and 3′-termini, and a high complementarity of approximately 20 nt in 5′- and 3′-terminal sequences. Transmission electron microscopy confirmed the presence of virus-like particles. JSA ringspot disease was found to be transmitted by an eriophyid mite (subclass Acari, superfamily Eriophyoidea) that belongs to the family Diptilomiopidae. Taken together, these results identified the virus responsible for the ringspot disease of JSA as a new member of the genus, Emaravirus, which we named as the Japanese star anise ringspot-associated virus (JSARaV). Moreover, this is the first report noting that eriophyid mites of the family Diptilomiopidae are capable of transmitting emaravirus.

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