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991.
The anticonvulsant activities of cannabinoid compounds have been shown in various models of seizure and epilepsy. At least, part of antiseizure effects of cannabinoid compounds is mediated through calcium (Ca2+) channels. The L-type Ca2+ channels have been shown to be important in various epilepsy models. However, there is no data regarding the role of L-type Ca2+ channels in protective action of cannabinoids on acute and chronic models of seizure. In this study, the effects of cannabinoid compounds and L-type Ca2+ channels blockers, either alone or in combination were investigated using acute model of pentylenetetrazole (PTZ)-induced seizure in mice and chronic model electrical kindling of amygdala in rats. Pretreatment of mice with both cannabinoid CB1 receptor agonist arachidonyl-2′-chloroethylamide (ACEA) and endocannabinoid degradating enzyme inhibitor cyclohexylcarbamic acid 3′-carbamoyl-biphenyl-3-yl ester (URB597) produced a protective effect against PTZ-induced seizure. Administration of various doses of the two L-type Ca2+ channel blockers verapamil and diltiazem did not alter PTZ-induced seizure threshold. However, co-administration of verapamil and either ACEA or URB597 attenuated the protective effect of cannabinoid compounds against PTZ-induced seizure. Also, pretreatment of mice with diltiazem blocked the anticonvulsant activity of both ACEA and URB597. Moreover, (R)-(+)-[2,3-dihydro-5-methyl-3[(4-morpholinyl)methyl]pyrrolo[1,2,3-de]-1,4-benzoxazinyl]-(1-naphthalenyl) methanone mesylate (WIN55,212-2), the non-selective cannabinoid CB1 and CB2 receptor agonist showed anticonvulsant effect in amygdala-kindled rats. However, co-administration of WIN55,212-2 and verapamil attenuated the protective properties of WIN55,212-2. Our results showed that the anticonvulsant activity of cannabinoid compounds is mediated, at least in part, by L-type Ca2+ channels in these two models of convulsion and epilepsy.  相似文献   
992.
Patients with glioblastoma multiforme (GBM) have poor therapeutic outcomes despite their current therapy. In an attempt to increase the efficacy of therapy for GBM, we studied the efficacy of arsenic trioxide (ATO), a newly introduced treatment for glioma, combined with silibinin, a natural polyphenolic flavonoid, in the GBM cell line, U87MG. The combination therapy synergically inhibited metabolic activity, cell proliferation, and gelatinase A and B activities; it also increased apoptosis. Additionally, it decreased the mRNA level of cathepsin B, uPA, matrix metalloproteinase-2 and 9, membrane type 1-MMP, survivin, BCL2, CA9; it increased mRNA level of caspase-3. Altogether, these results showed that ATO and silibinin in some cases improved and/or complemented the anticancer effects. This study may supply insight into the design of new combination cancer therapies to cells intrinsically less sensitive to routine therapies and suggested a new combination therapy for the highly invasive human glioma treatment.  相似文献   
993.
The current consensus for the eukaryote tree of life consists of several large assemblages (supergroups) that are hypothesized to describe the existing diversity. Phylogenomic analyses have shed light on the evolutionary relationships within and between supergroups as well as placed newly sequenced enigmatic species close to known lineages. Yet, a few eukaryote species remain of unknown origin and could represent key evolutionary forms for inferring ancient genomic and cellular characteristics of eukaryotes. Here, we investigate the evolutionary origin of the poorly studied protist Collodictyon (subphylum Diphyllatia) by sequencing a cDNA library as well as the 18S and 28S ribosomal DNA (rDNA) genes. Phylogenomic trees inferred from 124 genes placed Collodictyon close to the bifurcation of the "unikont" and "bikont" groups, either alone or as sister to the potentially contentious excavate Malawimonas. Phylogenies based on rDNA genes confirmed that Collodictyon is closely related to another genus, Diphylleia, and revealed a very low diversity in environmental DNA samples. The early and distinct origin of Collodictyon suggests that it constitutes a new lineage in the global eukaryote phylogeny. Collodictyon shares cellular characteristics with Excavata and Amoebozoa, such as ventral feeding groove supported by microtubular structures and the ability to form thin and broad pseudopods. These may therefore be ancient morphological features among eukaryotes. Overall, this shows that Collodictyon is a key lineage to understand early eukaryote evolution.  相似文献   
994.
995.

Background

There is evidence that opium addiction has immunosuppressant effects. Coronary artery disease (CAD) is a condition resulted from atherosclerosis which is dependent on the immune response.

Purpose

To evaluate plasma levels of interleukin-6 and interleukin-1Ra in 30 patients with three-vessel coronary artery disease, ejection fraction of more than 35% and to evaluate their changes after prognostic treadmill test in 15 opium addicted and 15 non-addicted patients.

Methods

The participants underwent prognostic treadmill test and plasma levels of interleukin-6 (IL-6) and interleukin-1Ra (IL-1Ra) were evaluated with ELISA method before, just after and 4 hours after the test.

Results

IL-1Ra (2183 pg/ml) tended to decrease over time in the opium addicted group (1372 pg/ml after prognostic treadmill test and 1034 pg/ml 4 hours after that), although such decrease did not reach the statistical significance. IL-1Ra levels were significantly higher in opium addicted than in non addicted patients. Opium addiction had no significant effect on IL-6 changes.

Conclusion

Consumption of opium in CAD patients is associated with higher IL-1Ra levels.  相似文献   
996.

Background

Health of migrants is a major public health challenge faced by governments and policy makers. Asian Indians are among the fastest growing migration groups across Asia and the world, but the impact of migration and acculturation on diabetes and diabetes-related eye complications among Indians living in urban Asia remains unclear.

Methodologies/Principal Findings

We evaluated the influence of migration and acculturation (i.e., migration status and length of residence) on the prevalence of type-2 diabetes mellitus (T2DM) and diabetes-related eye complications (diabetic retinopathy (DR) and cataract), among first-generation (defined as participant born in India with both parents born in India, n = 781) and second-generation (participants born in Singapore with both parents born in India, n = 1,112) Indian immigrants from a population-based study of Adult Indians in Singapore. Diabetes was defined as HbA1c≥6.5%, use of diabetic medication or a physician diagnosis of diabetes. Retinal and lens photographs were graded for the presence of DR and cataract. Compared to first generation immigrants, second generation immigrants had a higher age- and gender-standardized prevalence of T2DM (34.4% versus 29.0%, p<0.001), and, in those with T2DM, higher age- and gender-standardized prevalence of DR (31.7% versus 24.8%, p<0.001), nuclear cataract (13.6% versus 11.6%, p<0.001), and posterior sub-capsular cataract (6.4% versus 4.6%, p<0.001). Among first generation migrants, longer length of residence was associated with significantly younger age of diagnosis of diabetes and greater likelihood of having T2DM and diabetes-related eye complications.

Conclusion

Second generation immigrant Indians and longer length of residence are associated with higher prevalence of diabetes and diabetes-related complications (i.e., DR and cataract) among migrant Indians living in Singapore. These data highlight potential worldwide impacts of migration patterns on the risk and burden of diabetes.  相似文献   
997.
AIM: To improve the isolation and expansion of human marrow-derived mesenchymal stem cells (MSCs) based on rat samples. METHODS: Based on the fact that rat MSCs are relatively easy to obtain from a small aspirate, bone marrow-derived MSCs from rat were cultured and characterized to set up the different protocols used in this study. Then, accordingly, almost the same protocols were performed on human healthy bone marrow samples, after obtaining approval of the ethics committee and gaining informed consent. We used different protocols and culture conditions, including the type of basal media and the culture composition. The MSCs were characterized by immunophenotyping and differentiation. RESULTS: There was no difference in morphology and proliferation capacity between different culture media at the first passage. During the 5-7th passages, the cells gradually lost their morphology and proliferation potential on Dulbecco’s modified Eagle’s medium (DMEM) high glucose and α modified Eagle’s medium. Although the cells expanded rapidly for up to 10 passages on DMEM low glucose containing 10% to 15% fetal calf serum (FCS), their proliferation was arrested without change in morphology and differentiation capacity at the third passage on 5% FCS. Flow cytometric analysis and functional tests confirmed that more than 90% of marrow cells which were isolated and expanded by our selective protocols were MSCs. CONCLUSION: We improved the isolation and expansion of human bone marrow derived MSCs, based on rat sample experiments, for further experimental and clinical use.  相似文献   
998.
When plastids are transferred between eukaryote lineages through series of endosymbiosis, their environment changes dramatically. Comparison of dinoflagellate plastids that originated from different algal groups has revealed convergent evolution, suggesting that the host environment mainly influences the evolution of the newly acquired organelle. Recently the genome from the anomalously pigmented dinoflagellate Karlodinium veneficum plastid was uncovered as a conventional chromosome. To determine if this haptophyte-derived plastid contains additional chromosomal fragments that resemble the mini-circles of the peridin-containing plastids, we have investigated its genome by in-depth sequencing using 454 pyrosequencing technology, PCR and clone library analysis. Sequence analyses show several genes with significantly higher copy numbers than present in the chromosome. These genes are most likely extrachromosomal fragments, and the ones with highest copy numbers include genes encoding the chaperone DnaK(Hsp70), the rubisco large subunit (rbcL), and two tRNAs (trnE and trnM). In addition, some photosystem genes such as psaB, psaA, psbB and psbD are overrepresented. Most of the dnaK and rbcL sequences are found as shortened or fragmented gene sequences, typically missing the 3'-terminal portion. Both dnaK and rbcL are associated with a common sequence element consisting of about 120 bp of highly conserved AT-rich sequence followed by a trnE gene, possibly serving as a control region. Decatenation assays and Southern blot analysis indicate that the extrachromosomal plastid sequences do not have the same organization or lengths as the minicircles of the peridinin dinoflagellates. The fragmentation of the haptophyte-derived plastid genome K. veneficum suggests that it is likely a sign of a host-driven process shaping the plastid genomes of dinoflagellates.  相似文献   
999.
Cell manufacturing for clinical applications is a unique form of biologics manufacturing that relies on maintenance of stringent work practices designed to ensure product consistency and prevent contamination by microorganisms or by another patient's cells. More extensive, prolonged laboratory processes involve greater risk of complications and possibly adverse events for the recipient, and so the need for control is correspondingly greater. To minimize the associate risks of cell manufacturing adhering to international quality standards is critical. Current good tissue practice (cGTP) and current good manufacturing practice (cGMP) are examples of general standards that draw a baseline for cell manufacturing facilities. In recent years, stem cell researches have found great public interest in Iran and different cell therapy projects have been started in country. In this review we described the role of our tissue banking experiences in establishing a new cGMP cell manufacturing facility. The authors concluded that, tissue banks and tissue banking experts can broaden their roles from preparing tissue grafts to manufacturing cell and tissue engineered products for translational researches and phase I clinical trials. Also they can collaborate with cell processing laboratories to develop SOPs, implement quality management system, and design cGMP facilities.  相似文献   
1000.
We have isolated cells of unculturable radiolarians from marine coastal waters. Individual cells were subjected to single cell whole genome amplification (SCWGA) and gene-targeted PCR. Using this approach we recover a surprisingly large diversity of sequences related to the enigmatic marine alveolate groups 1 and 2 (MALV I and MALV II) that most likely represent intracellular symbionts or parasites of the radiolarian cells. 18S rDNA phylogeny of the MALV sequences reveals 4 distinct clades of radiolarian associates here named Radiolarian Associated Sequences (RAS) 1-4. One clade of both phaeodarian and radiolarian associates and one clade of only phaeodarian associates are also identified. The MALV sequences cluster according to host type, i.e. sequences from associates identified in radiolarians, fish, copepods, ciliates or dinoflagellates are not intermixed but separated into distinct clades. This implies several independent colonizations of host lineages and links a large diversity of MALV to radiolarian-associated species. This demonstrates that radiolarians may be an important reservoir for MALV, making them a key group for understanding the impact of intracellular symbionts on the marine ecosystem. This study shows that applying SCWGA on unculturable cells is a promising approach to study the vast diversity and interactions of intracellular eukaryote organisms.  相似文献   
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