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91.

Aim

This study aimed to evaluate the treatment result of intensity-modulated radiation therapy (IMRT) in a large number of Japanese patients with prostate cancer.

Background

A total of 1091 patients with localized prostate cancer were recruited between March 2006 and July 2014. The patients were stratified into low- (n = 205 [18.8%]), intermediate- (n = 450 [41.2%]), high- (n = 345 [31.6%]), and very high-risk (n = 91 [8.3%]) groups according to the National Comprehensive Cancer Network classification. All patients were irradiated via IMRT at a dose of 74–78 Gy with or without androgen-deprivation therapy. The mean follow-up period was 50 months (range, 2–120 months).

Results

The biochemical failure-free rate (BFFR), the clinical failure-free rate, and the overall survival rate at the 5-year follow-up for all patients was 91.3%, 96.2%, and 99.1%, respectively. In univariate analysis, the prostate-specific antigen (PSA) levels (≤20 vs. >20 ng/ml) were significantly correlated with BFFR. A trend toward higher BFFR was noted in patients with a Gleason score (GS) of ≤7 than in patients with GS ≥8. In multivariate analysis, only PSA (≤20 vs. >20 ng/ml) was significantly correlated with BFFR. The cumulative incidence rate of gastrointestinal and genitourinary toxicity (≥grade 2) at the 5-year follow-up was 11.4% and 4.3%, respectively.

Conclusions

The findings of this study indicate that IMRT is well tolerated and is associated with both good long-term tumor control and excellent outcomes in patients with localized prostate cancer.  相似文献   
92.
Embryonic external genitalia (genital tubercle [GT]) protrude from the cloaca and outgrow as cloacal development progresses. Individual gene functions and knockout phenotypes in GT development have been extensively analyzed; however, the interactions between these genes are not fully understood. In this study, we investigated the role of p63, focusing on its interaction with the Shh–Wnt/Ctnnb1–Fgf8 pathway, a signaling network that is known to play a role in GT outgrowth. p63 was expressed in the epithelial tissues of the GT at E11.5, and the distal tip of the GT predominantly expressed the ΔNp63α isoform. The GTs in p63 knockout embryos had normal Shh expression, but CTNNB1 protein and Fgf8 gene expression in the distal urethral epithelium was decreased or lost. Constitutive expression of CTNNB1 in p63-null embryos restored Fgf8 expression, accompanied by small bud structure development; however, such bud structures could not be maintained by E13.5, at which point mutant GTs exhibited severe abnormalities showing a split shape with a hemorrhagic cloaca. Therefore, p63 is a key component of the signaling pathway that triggers Fgf8 expression in the distal urethral epithelium and contributes to GT outgrowth by ensuring the structural integrity of the cloacal epithelia. Altogether, we propose that p63 plays an essential role in the signaling network for the development of external genitalia.  相似文献   
93.
Berberine chloride (1) and the structurally related compounds were assessed for the anti-human cytomegalovirus (HCMV) activity using the plaque assay. The anti-HCMV activity (IC(50) 0.68 microM) of 1 was equivalent to that (IC(50) 0.91 microM) of ganciclovir (GCV). The mechanism of action by which 1 inhibits the replication of HCMV is presumed to be different from that of GCV; 1 would interfere with intracellular events after virus penetration into the host cells and before viral DNA synthesis.  相似文献   
94.

Aim

To define the optimal margin on MRI scans in the re-radiation planning of recurrent glioblastoma using methionine positron emission tomography (MET-PET).

Background

It would be very useful if the optimal margin on MRI to cover the uptake area on MET-PET is known.

Materials and Methods

CT, MRI, and MET-PET were performed separately over the course of 2 weeks. Among the MRI scans, we used the contrast-enhanced T1-weighted images (Gd-MRI) and T2-weighted images (T2-MRI). The Gd-MRI-based clinical target volume (CTV) (CTV-Gd) and the T2-MRI-based CTV (CTV-T2) were defined as the contrast-enhanced area on Gd-MRI and the high intensity area on T2-MRI, respectively. We defined CTV x mm (x = 5, 10, 15, 20) as x mm outside the CTV. MET-PET-based CTV (CTV-MPET) was defined as the area of accumulation of MET-PET. We calculated the sensitivity and specificity of CTV-Gd and CTV-T2 following comparison with CTV-MPET, which served as the gold standard in this study.

Results

The sensitivity of CTV-T2 5 mm (98%) was significantly higher than CTV-T2 (87%), and there was no significant difference in the sensitivity between CTV-T2 5 mm and CTV T2 10, 15, or 20 mm. The sensitivity of CTV-Gd 20 mm (97%) was lower than that of CTV-T2 5 mm (98%).

Conclusions

A margin of at least 5 mm around the high intensity area on T2-MRI is necessary in the target volume delineation of recurrent glioblastoma for the coverage of MET-PET findings in re-radiation therapy planning.  相似文献   
95.
We investigated the murine antibody response to recombinant p17 (rp17) of human immunodeficiency virus type 1 (HIV-1) and the human antibody response directed to p17 in HIV-1 infection. Three large peptides covering residues 12-29, 53-87 and 87-115 of p17 were synthesized. The cysteine residues 57 and 87 of peptide 53-87 were reoxidized to form a disulfide bridge. Eighteen out of 19 murine monoclonal anti-rp17 antibodies had relatively high affinities (KA = 1.9 × 105?1.4 × 108 M?1) with one of the 3 p17 peptides in the liquid phase. Each monoclonal antibody reacted only with one particular peptide and had no reactivity with the other 2 p17 peptides. All the monoclonal antibodies reacted with rp17 in the liquid phase with a reasonable degree of affinity (KA = 2.0 × 105?1.8 × 107 M?1). Four HIV-1 carrier sera, which were positive in ELISA using rp17 as the antigen, reacted positively in an ELISA using 3 p17 peptides which were used to titrate murine monoclonal antibodies. Murine monoclonal antibodies having specificity for the 3 p17 peptides stained live HIV-1-infected cells by means of indirect membrane immunofluorescence, irrespective of their specificity. This suggests that the various portions of p17 (at least 3 regions of p17) were exposed on the surface of live infected cells, probably as short polypeptide chains.  相似文献   
96.

Background

Loss to follow up (LTFU) is an important prognostic factor in patients with HIV-1 infection. The impact of illicit drug use on LTFU of patients with HIV-1 infection is unknown in Japan.

Methods

A single center observational study was conducted to elucidate the impact of illicit drug use on LTFU at a large HIV clinic in Tokyo. LTFU was defined as those who discontinued their visits to the clinic for at least 12 months and were not known to be under the care of other facilities or have died within 12 months of their last visit. Patients who first visited the clinic between January 2005 and August 2010 were enrolled. Information on illicit drug use was collected in a structured interview and medical charts. Comparison of the effects of illicit drug use and no use on LTFU was conducted by uni- and multi-variate Cox hazards models as the primary exposure.

Results

The study subjects were 1,208 patients, mostly Japanese men, of relatively young age, and infected through homosexual contact. A total of 111 patients (9.2%) were LTFU (incidence: 24.9 per 1,000 person-years). Among illicit drug users and non users, 55 (13.3%) and 56 (7.1%) patients, respectively, were LTFU, with incidence of 35.7 and 19.2 per 1,000 person-years, respectively. Uni- and multi-variate analyses showed that illicit drug use was a significant risk for LTFU (HR=1.860; 95% CI, 1.282-2.699; p=0.001) (adjusted HR=1.544; 95% CI, 1.028-2.318; p=0.036). Multivariate analysis also identified young age, high CD4 count, no antiretroviral therapy, and no health insurance as risk factors for LTFU.

Conclusions

The incidence of LTFU among illicit drug users was almost twice higher than that among non users. Effective intervention for illicit drug use in this population is warranted to ensure proper treatment and prevent the spread of HIV.  相似文献   
97.
Nucleo-cytoplasmic large DNA viruses (NCLDVs) constitute a group of eukaryotic viruses that can have crucial ecological roles in the sea by accelerating the turnover of their unicellular hosts or by causing diseases in animals. To better characterize the diversity, abundance and biogeography of marine NCLDVs, we analyzed 17 metagenomes derived from microbial samples (0.2–1.6 μm size range) collected during the Tara Oceans Expedition. The sample set includes ecosystems under-represented in previous studies, such as the Arabian Sea oxygen minimum zone (OMZ) and Indian Ocean lagoons. By combining computationally derived relative abundance and direct prokaryote cell counts, the abundance of NCLDVs was found to be in the order of 104–105 genomes ml−1 for the samples from the photic zone and 102–103 genomes ml−1 for the OMZ. The Megaviridae and Phycodnaviridae dominated the NCLDV populations in the metagenomes, although most of the reads classified in these families showed large divergence from known viral genomes. Our taxon co-occurrence analysis revealed a potential association between viruses of the Megaviridae family and eukaryotes related to oomycetes. In support of this predicted association, we identified six cases of lateral gene transfer between Megaviridae and oomycetes. Our results suggest that marine NCLDVs probably outnumber eukaryotic organisms in the photic layer (per given water mass) and that metagenomic sequence analyses promise to shed new light on the biodiversity of marine viruses and their interactions with potential hosts.  相似文献   
98.
Barttin, a gene product of BSND, was identified as a fourth gene responsible for Bartter syndrome. The co-expression of barttin with CLC-K chloride channels has been demonstrated to dramatically induce the expression of CLC-K current. However, it remains unknown how barttin interacts with CLC-K channels in mammalian cells and how the mutations of barttin lead to Bartter syndrome. In an attempt to clarify the effect of barttin expression on CLC-K2 cellular localization, we examined the expression of the CLC-K2 chloride channel and barttin, solely and in combination, in transient and stable expression systems in mammalian cells. In addition, we generated several stable cell lines expressing mutant barttins to clarify the consequence of the previously reported barttin mutations in Bartter syndrome. In immunocytochemistry, CLC-K2 was retained in the Golgi in the absence of barttin expression, but delivered to the plasma membrane when barttin was present. Barttin was coprecipitated with CLC-K2, suggesting a protein-protein interaction. Disease-causing mutant barttins, especially R8L, were retained intracellularly, but their binding ability to CLC-K2 was preserved. This led to a retention of CLC-K2 in intracellular organelles with barttin, and a loss of plasma membrane localization. The stability of the CLC-K2 protein was also markedly increased by coexpression with barttin. These results clarified that barttin determined cellular localization of CLC-K2 by protein-protein interaction. Thus, the mislocalization of CLC-K2 was identified as the molecular pathogenesis of Bartter syndrome by mutant barttins.  相似文献   
99.
Carotenes have attracted much attention in recent years for their biological function in processes such as photosynthesis. The characterization of carotenes is difficult, however, because they consist of only carbon and hydrogen atoms, without oxygen. In the present study, we systematically examined the chemical structures of more than 30 carotenes, including most of the carotenes found in phototrophic organisms, and observed their elution order using a Novapak C18 HPLC column with simple isocratic elution. The elution order of the carotenes was C30, C40,C45 then C50. The C40 carotenes with fewer conjugated double bonds (N) had longer retention times. With respect to the end groups, the carotenes eluted in the following order: φ, Ψ, ∈ then β end groups. Furthermore, absorption spectra in the HPLC eluent used were recorded with a photodiode-array detector. A greater N value was associated with a longer absorption maximum wavelength. Since the conjugated end groups (φ and β) influenced the absorption spectra and the non-conjugated end groups (Ψ and ∈) did not, the number of conjugated end groups (zero, one and two) was clearly distinguishable. Therefore, the chemical structures of carotenes can be easily determined by a combination of the HPLC retention times and the absorption spectra. This revised version was published online in June 2006 with corrections to the Cover Date.  相似文献   
100.
To assess evolutional changes in the expression pattern of Otx paralogues, expression analyses were undertaken in fugu, bichir, skate and lamprey. Together with those in model vertebrates, the comparison suggested that a gnathostome ancestor would have utilized all of Otx1, Otx2 and Otx5 paralogues in organizer and anterior mesendoderm for head development. In this animal, Otx1 and Otx2 would have also functioned in specification of the anterior neuroectoderm at presomite stage and subsequent development of forebrain/midbrain at somite stage, while Otx5 expression would have already been specialized in epiphysis and eyes. Otx1 and Otx2 functions in anterior neuroectoderm and brain of the gnathostome ancestor would have been differentially maintained by Otx1 in a basal actinopterygian and by Otx2 in a basal sarcopterygian. Otx5 expression in head organizer and anterior mesendoderm seems to have been lost in the teleost lineage after divergence of bichir, and also from the amniotes after divergence of amphibians as independent events. Otx1 expression was lost from the organizer in the tetrapod lineage. In contrast, in a teleost ancestor prior to whole genome duplication, Otx1 and Otx2 would have both been expressed in the dorsal margin of blastoderm, embryonic shield, anterior mesendoderm, anterior neuroectoderm and forebrain/midbrain, at respective stages of head development. Subsequent whole genome duplication and the following genome changes would have caused different Otx paralogue usages in each teleost lineage. Lampreys also have three Otx paralogues; their sequences are highly diverged from gnathostome cognates, but their expression pattern is well related to those of skate Otx cognates.  相似文献   
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