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1.
In an attempt to investigate the interaction between the changes of cytokines and acute phase reactants after transcatheter arterial chemoembolization therapy (TACE), the levels of interleukin 6 (IL-6), interleukin 8 (IL-8), C-reactive protein (CRP) and pancreatic secretory trypsin inhibitor (PSTI) in the blood of patients with unresectable hepatocellular carcinoma (HCC) were measured. Before the therapy, serum IL-6 and plasma IL-8 levels were detectable in 77.8% and 28.5%, respectively, of patients with HCC. Levels of serum IL-6 and plasma IL-8 increased after TACE and reached a peak on day 3 in all patients (18/18) and in 87.5% of patients (12/14), respectively. Both blood levels of IL-6 and IL-8 reached a peak earlier than those of CRP and PSTI did after the therapy. When the maximal values of IL-6 were compared with those of CRP and PSTI, there were significant positive correlations (r = 0.63, P < 0.01 and r = 0.81, P < 0.01, respectively). Similarly, comparisons of the maximal values of IL-8 with those of CRP and PSTI gave a significant correlation (r = 0.68, P < 0.01 and r = 0.67, P < 0.05, respectively). However, no significant correlation was found between the elevation of IL-6 and IL-8.  相似文献   
2.
The vascularization of the node-leaf continuum in the first to eighth foliage leaves of the first-year plant ofMagnolia virginiana is investigated. The cotyledonary node is a 4-trace, 3-lacunar type. Vascularization in the cotyledonary node is fundamentally different from that in the folair node of the same plant. As a result, the cotyledonary vascularization is only described but not compared to that in the foliar node-leaf continuum. Considerable diversity occurs in the node-leaf vascularization of the first-year plants. A 5-trace, 4-lacunar vascular system is constant in the lower folair nodes; this is considered to be the fundamental vascular pattern in the node-leaf continuum of the species. In contrast, the nodal anatomy and petiolar vascularization fluctuate widely in the third to eighth leaves of the first-year plants. Variation is found not only between different nodes of a single plant but even in the corresponding nodes of different individuals. The evidence clearly indicates that variation always correlates with certain members of the leaf-trace complement; thus, either the ventral and/or marginal lateral bundles undergo phylogenetical reduction or amplification.  相似文献   
3.
Transparent gels containing about 2% protein were obtained by mixing alkaline dope solution of 7S or 11S soybean proteins with alcohol. The 7S component showed the ability to form a stronger gel than the 11S. This phenomenon depended on pH and alcohol concentration. In 66 % ethanol, the viscosity of the 7S and 11S reached maxima at pH 11.4 and 11.2, respectively. Above these pH levels where further unfolding and dissociation into subunits of the protein molecules occur, the viscosity decreased rather. The effectiveness of alcohol to increase viscosity increased in the order; n-butanol < tert-butanol < n-propanol < iso-propanol < ethanol < methanol. Alcohols having minor hydrophobicity were more effective for increasing viscosity, but ethylene glycol was ineffective. The addition of NaCl or 2-mercaptoethanol to ethanol-mixed alkaline dope solutions resulted in the remarkable increment of the viscosity, especially for the 7S.  相似文献   
4.
The rate constant of modification of a specific thiol group, SH2, with N-ethylmaleimide (NEM) has been used to estimate the conformational change in the local area containing SH2 (SH2 region) of skeletal myosin as a structural probe. The rate of Mg2+-ATP-induced SH2 modification of subfragment-1 (S-l) isozymes was regulated by Ca2+ in the pCa range below 6.4 and was not regulated in the pCa range above 6.4. No substantial difference between S-1 containing alkali light chain, A1, (S-1(A1)) and S-1 containing alkali light chain, A2, (S-1(A2)) was observed in the Ca2+-dependent rate of SH2 modification. Due to the presence of this Ca2+ regulation in myosin (absence in S-1 isozymes) in the pCa range above 6.4, absence of 5,5-dithiobis-(2-nitrobenzoic acid) (DTNB) light chain in S-1 isozymes, and high affinity of Ca2+ for DTNB light chain, this Ca2+ regulation in the pCa range above 6.4 is possibly related to the Ca2+ binding to DTNB light chain. F-Actin, which is entirely free from tropomyosin and troponin, enhanced the rate of Mg2+-ATP-induced SH2 modification of S-1 isozymes equally and of myosin, and reduced the Ca2+ sensitivity with an increase in F-actin concentration.  相似文献   
5.
Summary Liposomes composed of chemically synthesized glyceroglycolipids, such as 1,2-dipalmityl-[-cellobiosyl-(1 3)]-glycerol (Cel-DAG), 1,2-dipalmityl-[-lactosyl-(1 3)]-glycerol, or 1,2-dipalmityl-[-maltosyl-(1 3)]-glycerol, were found to enhance protective immunity against transplantable tumor cells (sarcoma 180) in ICR mice. Peritoneal exudate cells prepared from mice treated in vivo with Cel-DAG showed cytostatic activity in vitro against the mouse leukemia cell line, EL-4. Adherent cells separated from this preparation showed similar activity. Peritoneal cells from polypeptone-injected mice acquired appreciable cytostatic activity when incubated in vitro in the presence of glyceroglycolipid liposomes. The adherent cell fraction alone showed rather weak cytostatic activity when pretreated with the glyceroglycolipids, and full activity was restored by supplementing with the nonadherent cell fraction. The ability of glycolipids to induce tumoricidal effects was affected by cholesterol content: with increasing cholesterol content, the activities decreased. Cholesterol-free glycolipid liposomes were taken more efficiently by macrophages than cholesterol-containing liposomes. Cholersterol modifies the surface property of glyceroglycolipid liposomes. Activation of macrophages is responsible for enhancement of protective immunity against tumor cells by injection of these glycolipids in vivo.This work was supported in part by Grants-in-Aid (Nos. 58010010, and 59870076) for Scientific Research from the Ministry of Education, Science and Culture of Japan  相似文献   
6.
S R Bauer  A Kudo    F Melchers 《The EMBO journal》1988,7(1):111-116
DNA from several mammals, including humans, was found to contain one or more restriction enzyme digested DNA fragments which hybridized to the mouse VpreB gene under stringencies demonstrating at least 70% nucleotide sequence homologies, indicating that the VpreB locus may be widespread and highly conserved among mammals. A human VpreB genomic clone was isolated and sequenced. Two exons and the intervening intron are spaced almost identically as in the mouse VpreB1 gene, and show 76% sequence homology to the mouse gene. As in the mouse VpreB1 gene, the 5' end of the human VpreB gene contains characteristic features of Ig domains, while the 3' end is Ig non-related. This 3' Ig non-related structure of the VpreB gene(s) may, therefore, have existed before the speciation of humans and mice over 65 million years ago. Sequences encoding the entire putative second framework region and a stretch in the third framework region are identical in human and mouse VpreB. the human VpreB gene appears to be selectively expressed in human pre-B cell lines as an 0.85 kb poly(A)+ RNA. Its expression promises to be a useful marker for the detection of normal and malignant human pre-B lymphocytes.  相似文献   
7.
8.
The genes for cellulases of alkalophilic Bacillus sp. strain N-4 were cloned in Escherichia coli with pBR322. Plasmids pNK1 and pNK2 were isolated from the transformants producing carboxymethyl cellulase, and the carboxymethyl cellulase genes cloned were in 2.0- and 2.8-kilobase-pair HindIII fragments, respectively. On the DNA level, the pNK1 fragment had a different restriction map from that of the pNK2 fragment, but the genomic hybridization experiments showed partial homology among these fragments. A total of 74 and 34% of the enzyme activities were observed in the periplasmic space of E. coli carrying the plasmids pNK1 and pNK2 , respectively. The carboxymethyl cellulase thus produced had broad pH activity curves (pH of 5 to 10.9) and was stable up to 75 degrees C.  相似文献   
9.
Two plasmids containing the penicillinase gene of alkalophilic Bacillus sp. strain 170, pEAP1 and pEAP2, were constructed. Most of the penicillinase produced by Escherichia coli, which carried these plasmids, was found in the culture medium. This excretion is caused by the cloned DNA fragment which contains some component that changes the outer membrane of E. coli.  相似文献   
10.
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