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Christel Marie-Etancelin Eduardo Manfredi Marie-Rose Aurel Fran?ois Pailler Jean Arhainx Edmond Ricard Gilles Lagriffoul Philippe Guillouet Bernard Bibé Francis Barillet 《遗传、选种与进化》2006,38(2):183-200
The milking ability of Lacaune ewes was characterised by derived traits of milk flow patterns, in an INRA experimental farm, from a divergent selection experiment in order to estimate the correlated effects of selection for protein and fat yields. The analysis of selected divergent line effects (involving 34 616 data and 1204 ewes) indicated an indirect improvement of milking traits (+17% for maximum milk flow and -10% for latency time) with a 25% increase in milk yield. Genetic parameters were estimated by multi-trait analysis with an animal model, on 751 primiparous ewes. The heritabilities of the traits expressed on an annual basis were high, especially for maximum flow (0.54) and for latency time (0.55). The heritabilities were intermediate for average flow (0.30), time at maximum flow (0.42) and phase of increasing flow (0.43), and low for the phase of decreasing flow (0.16) and the plateau of high flow (0.07). When considering test-day data, the heritabilities of maximum flow and latency time remained intermediate and stable throughout the lactation. Genetic correlations between milk yield and milking traits were all favourable, but latency time was less milk yield dependent (-0.22) than maximum flow (+0.46). It is concluded that the current dairy ewe selection based on milk solid yield is not antagonistic to milking ability. 相似文献
74.
Agrawal AK Kielan W Katib A Grzebieniak Z Skalski A Grzebieniak T Duda-Barcik L Janocha A Siewiński M 《Folia histochemica et cytobiologica / Polish Academy of Sciences, Polish Histochemical and Cytochemical Society》2010,48(4):513-517
The work's objective is to answer the question whether there is any possibility of activity inhibition of cysteine peptidases inhibitors playing an important role in key processes accompanying cancer formation, including pancreas. There is a justified speculation that specific inhibitors of these enzymes may inhibit development of cancer processes by inhibiting their activity. In vitro studies confirmed that these enzymes in ascitic fluid were inhibited with egg whites inhibitors even to 90% of their original activity. 相似文献
75.
Correa TC Brohem CA Winnischofer SM da Silva Cardeal LB Sasahara RM Taboga SR Sogayar MC Maria-Engler SS 《Journal of cellular biochemistry》2006,99(1):156-167
Invasive behavior is the pathological hallmark of malignant gliomas, being responsible for the failure of surgery, radiation, and chemotherapy. Matrix metalloproteinases (MMPs) are essential for proper ECM remodeling and invasion. The tumor and metastasis suppressor RECK protein regulates at least three members of the MMPs family: MMP-2, MMP-9, and MT1-MMP. In order to mimic the in vivo invasion process, A172 and T98G, respectively, non-invasive and invasive human glioblastoma cell lines, were cultured onto uncoated (control) or type I collagen gel-coated surface, and maintained for up to 7 days to allow establishment of the invasive process. We show that the collagen substrate causes decreased growth rates and morphological alterations correlated with the invasive phenotype. Electronic transmission microscopy of T98G cells revealed membrane invaginations resembling podosomes, which are typically found in cells in the process of crossing tissue boundaries, since they constitute sites of ECM degradation. Real time PCR revealed higher RECK mRNA expression in A172 cells, when compared to T98G cells and, also, in samples obtained from cultures where the invasive process was fully established. Interestingly, the collagen substrate increases RECK expression in A172 cells and the same tendency is displayed by T98G cells. MMPs-2 and -9 displayed higher levels of expression and activity in T98G cells, and their activities are also upregulated by collagen. Therefore, we suggest that: (1) RECK downregulation is critical for the invasiveness process displayed by T98G cells; (2) type 1 collagen could be employed to modulate RECK expression in glioblastoma cell lines. Since a positive correlation between RECK expression and patients survival has been noted in several types of tumors, our results may contribute to elucidate the complex mechanisms of malignant gliomas invasiveness. 相似文献
76.
Eun Ju Kim Dona C. Love Etzer Darout Mohannad Abdo Brian Rempel Stephen G. Withers Paul R. Rablen John A. Hanover Spencer Knapp 《Bioorganic & medicinal chemistry》2010,18(19):7058-7064
The title compound, which differs from the powerful O-GlcNAcase (OGA) inhibitor GlcNAc-thiazoline only at the chalcogen atom (Se for S), is a much weaker inhibitor in a direct OGA assay. In human cells, however, the selenazoline shows comparable ability to induce hyper-O-GlcNAc-ylation, and the two show similar reduction of insulin-stimulated translocation of glucose transporter 4 in differentiated 3T3 adipocytes. 相似文献
77.
Claire Remacle Catherine Bovie Marie-Rose Michel-Wolwertz Roland Loppes René F. Matagne 《Molecular & general genetics : MGG》1990,223(2):180-184
Summary The linear mitochondrial DNAs of the two infertile algal species Chlamydomonas smithii and C. reinhardtii are co-linear with the exception of a 1 kb intron ( intron) located in the cytochrome b gene of C. smithii. C. smithii also possesses an additional HpaI restriction site (H marker) located in the COXI gene, about 5 kb from the intron. In reciprocal crosses, C. smithii (H
++) × C. reinhardtii (H
––), the intron is transmitted to all diploid progeny, whereas the H marker is frequently transmitted either biparentally or paternally depending on whether the C. smithii parent is maternal (mt
+) or paternal (mt
–). In diploids resulting from artificial fusion between vegetative cells, the absolute transmission of a is accompanied by the frequent transmission of the H
+ marker, irrespective of the mating type of the parental strains. Finally, in reciprocal crosses between C. smithii (H
++) and recombinant H
–+ clones, the transmission of the H marker is predominantly paternal or biparental. These results allow us to conclude that (1) the a intron behaves as a group I intron whose unidirectional conversion influences the transmission of the H marker; and (2) the mt
– paternal mitochondrial genome is transmitted more often than the mt
+. The mating type has no effect in diploids obtained by artificial fusion. 相似文献
78.
79.
Fouda Amr Hassan Saad El-Din Abdo Abdullah M. El-Gamal Mamdouh S. 《Biological trace element research》2020,195(2):707-724
Biological Trace Element Research - In this study, metabolites involved in the free-biomass filtrates for three endophytic actinomycetes of Streptomyces capillispiralis Ca-1, Streptomyces... 相似文献
80.
Ayman A. Swelum Mohamed T. El-Saadony Mohamed Abdo Rabee A. Ombarak Elsayed O.S. Hussein Gamaleldin Suliman Ahmed R. Alhimaidi Aiman A. Ammari Hani Ba-Awadh Ayman E. Taha Khaled A. El-Tarabily Mohamed E. Abd El-Hack 《Saudi Journal of Biological Sciences》2021,28(5):3126-3136
Camel’s milk is an important part of staple diet in several parts of the world, particularly in the arid and semi-arid zones. Camel’s milk is rich in health-beneficial substances, such as bioactive peptides, lactoferrin, zinc, and mono and polyunsaturated fatty acids. These substances could help in the treatment of some important human diseases like tuberculosis, asthma, gastrointestinal diseases, and jaundice. Camel’s milk composition is more variable compared to cow’s milk. The effects of feed, breed, age, and lactation stage on milk composition are more significant in camel. Region and season significantly change the ratio of compounds in camel’s milk. Camel’s whey protein is not only composed of numerous soluble proteins, but also has indigenous proteases such as chymotrypsin A and cathepsin D. In addition to their high nutritional value, these whey proteins have unique characteristics, including physical, chemical, physiological, functional, and technological features that are useful in the food application. The hydrolysis of camel’s milk proteins leads to the formation of bioactive peptides, which affect major organ systems of the body and impart physiological functions to these systems. The camel’s milk has antioxidant, antimicrobial, angiotensin-I-converting enzyme (ACE)-inhibitory peptides, antidiabetic as well as anticholesterol activities. 相似文献