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61.
Sulfhydryl oxidases have found application in the improvement of both dairy and baking products due to their ability to oxidise thiol groups in small molecules and cysteine residues in proteins. A genome mining study of the available fungal genomes had previously been performed by our group in order to identify novel sulfhydryl oxidases suitable for industrial applications and a representative enzyme was produced, AoSOX1 from Aspergillus oryzae (Faccio et al. BMC Biochem 11:31, 2010). As a result of the study, a second gene coding for a potentially secreted sulfhydryl oxidase, AoSOX2, was identified in the genome of A. oryzae. The protein AoSOX2 was heterologously expressed in Trichoderma reesei and characterised with regard to both biochemical properties as well as preliminary structural analysis. AoSOX2 showed activity on dithiothreitol and glutathione, and to a lesser extent on D/L-cysteine and beta-mercaptoethanol. AoSOX2 was a homodimeric flavin-dependent protein of approximately 78 kDa (monomer 42412 Da) and its secondary structure presents alpha-helical elements. A. oryzae AoSOX2 showed a significant stability to pH and temperature.  相似文献   
62.
Despite promising results in the use of anti-epidermal growth factor receptor (EGFR) Abs for cancer therapy, several issues remain to be addressed. An increasing emphasis is being placed on immune effector mechanisms. It has become clear for other Abs directed to tumor targets that their effects involve the adaptive immunity, mainly by the contribution of Fc region-mediated mechanisms. Given the relevance of EGFR signaling for tumor biology, we wonder whether the oncogene inhibition could contribute to Ab-induced vaccine effect. In a mouse model in which 7A7 (an anti-murine EGFR Ab) and AG1478 (an EGFR-tyrosine kinase inhibitor) displayed potent antimetastatic activities, depletion experiments revealed that only in the case of the Ab, the effect was dependent on CD4(+) and CD8(+) T cells. Correspondingly, 7A7 administration elicited a remarkable tumor-specific CTL response in hosts. Importantly, experiments using 7A7 F(ab')(2) suggested that in vivo Ab-mediated EGFR blockade may play an important role in the linkage with adaptive immunity. Addressing the possible mechanism involved in this effect, we found quantitative and qualitative differences between 7A7 and AG1478-induced apoptosis. EGFR blocking by 7A7 not only prompted a higher proapoptotic effect on tumor metastases compared with AG1478, but also was able to induce apoptosis with immunogenic potential in an Fc-independent manner. As expected, 7A7 but not AG1478 stimulated exposure of danger signals on tumor cells. Subcutaneous injection of 7A7-treated tumor cells induced an antitumor immune response. This is the first report, to our knowledge, of a tumor-specific CTL response generated by Ab-mediated EGFR inhibition, suggesting an important contribution of immunogenic apoptosis to this effect.  相似文献   
63.
We performed histological examination of 69 samples of Acropora sp. manifesting different types of tissue loss (Acropora White Syndrome-AWS) from Hawaii, Johnston Atoll and American Samoa between 2002 and 2006. Gross lesions of tissue loss were observed and classified as diffuse acute, diffuse subacute, and focal to multifocal acute to subacute. Corals with acute tissue loss manifested microscopic evidence of necrosis sometimes associated with ciliates, helminths, fungi, algae, sponges, or cyanobacteria whereas those with subacute tissue loss manifested mainly wound repair. Gross lesions of AWS have multiple different changes at the microscopic level some of which involve various microorganisms and metazoa. Elucidating this disease will require, among other things, monitoring lesions over time to determine the pathogenesis of AWS and the potential role of tissue-associated microorganisms in the genesis of tissue loss. Attempts to experimentally induce AWS should include microscopic examination of tissues to ensure that potentially causative microorganisms associated with gross lesion are not overlooked.  相似文献   
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Risk factors for rhinitis, asthma and respiratory infections in the home environment were studied by a questionnaire survey. Totally 5775 occupants (≥18 years old) from a stratified random sample of multi-family buildings in Sweden participated (46%). 51.0% had rhinitis in the last 3 months (current rhinitis); 11.5% doctor diagnosed asthma; 46.4% respiratory infections in the last 3 months and 11.9% antibiotic medication for respiratory infections in the last 12 months. Associations between home environment and health were analyzed by multiple logistic regression, controlling for gender, age and smoking and mutual adjustment. Buildings constructed during 1960–1975 were risk factors for day time breathlessness (OR = 1.53, 95%CI 1.03–2.29). And those constructed during 1976–1985 had more current rhinitis (OR = 1.43, 95%CI 1.12–1.84) and respiratory infections (OR = 1.46, 95%CI 1.21–1.78). Cities with higher population density had more current rhinitis (p = 0.008) and respiratory infections (p<0.001). Rented apartments had more current rhinitis (OR = 1.23, 95%CI 1.07–1.40), wheeze (OR = 1.20, 95%CI 1.02–1.41), day time breathlessness (OR = 1.31, 95%CI 1.04–1.66) and respiratory infections (OR = 1.13, 95%CI 1.01–1.26). Living in colder parts of the country was a risk factor for wheeze (p = 0.03) and night time breathlessness (p = 0.002). Building dampness was a risk factor for wheeze (OR = 1.42, 95%CI 1.08–1.86) and day time breathlessness (OR = 1.57, 95%CI 1.09–2.27). Building dampness was a risk factor for health among those below 66 years old. Odor at home was a risk factor for doctor diagnosed asthma (OR = 1.49, 95%CI 1.08–2.06) and current asthma (OR = 1.52, 95%CI 1.03–2.24). Environmental tobacco smoke (ETS) was a risk factor for current asthma (OR = 1.53, 95%CI 1.09–2.16). Window pane condensation was a risk factor for antibiotic medication for respiratory infections (OR = 1.41, 95%CI 1.10–1.82). In conclusion, rhinitis, asthma and respiratory infections were related to a number of factors in the home environment. Certain building years (1961–1985), building dampness, window pane condensation and odor in the dwelling may be risk factors.  相似文献   
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We present solution-state NMR structures for two putative venom peptides from Sicarius dolichocephalus. These peptides were identified from cDNA libraries created from venom gland mRNA and then recombinantly expressed. They are the first structures from any species of Sicarius spiders, and the first peptide structures for any haplogyne spiders. These peptides are homologous to one another, and while they have at most only 20% sequence identity with known venom peptides their structures follow the inhibitor cystine knot motif that has been found in a broad range of venom peptides.  相似文献   
69.
In experiment 1, we used autoradiographic procedures to examine whether tamoxifen could displace 3H-estradiol labeling in the anterior hypothalamus and the caudal nucleus of the ventral hyperstriatum (HVc) of ovariectomized 20-day-old female zebra finches. There was no significant reduction in labeling of cells by 3H-estradiol in birds preinjected with unlabeled tamoxifen. In experiment 2, we found that injections of 3H-tamoxifen causedweak labeling of cells in the anterior hypothalamus of 20-day-old male and female zebra finches. These results are compatible with the idea that tamoxifen does not block the action of estradiol in the brain of zebra finches, and suggest that the effects of early tamoxifen treatment on the morphology of the song system may reflect central action of tamoxifen.  相似文献   
70.
This report describes the initial phase of social organization in Mongolian gerbils, Meriones unguiculatus, in large outdoor enclosures. These conditions offer a comparatively free choice for the establishment of bonds and social structure. In five replicate 20-day studies, the only social unit that formed was the male-female pair. The order of events was related to four sequential 5-day periods: (I) males established territories by male-male competition (1st to 2nd period); (II) females visited more than one male initially (1st and 2nd period), but developed a preference for one male or territory (3rd to 4th period); (III) as the females developed a preference, they also challenged other females having a preference for the same male or territory (approximately the 3rd period); (IV) as one female became locally dominant, some territorial males started chasing all but the dominant female. Males remained more active in territorial defence throughout the study. The defence became more intense as the females became strongly attached to one male and/or territory only. However females, after having established themselves in one particular male territory, spent significantly less time in the preferred area during the day of oestrus compared with the days before and after. Copulatory behaviour patterns, where observed, did not occur exclusively in interactions between territorial mates.  相似文献   
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