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991.
Map and analysis of microsatellites in the genome of <Emphasis Type="Italic">Populus</Emphasis>: The first sequenced perennial plant 下载免费PDF全文
We mapped and analyzed the microsatellites throughout 284295605 base pairs of the unambiguously assembled sequence scaffolds
along 19 chromosomes of the haploid poplar genome. Totally, we found 150985 SSRs with repeat unit lengths between 2 and 5
bp. The established microsatellite physical map demonstrated that SSRs were distributed relatively evenly across the genome
of Populus. On average, These SSRs occurred every 1883 bp within the poplar genome and the SSR densities in intergenic regions, introns,
exons and UTRs were 85.4%, 10.7%, 2.7% and 1.2%, respectively. We took di-, tri-, tetra-and pentamers as the four classes
of repeat units and found that the density of each class of SSRs decreased with the repeat unit lengths except for the tetranucleotide
repeats. It was noteworthy that the length diversification of microsatellite sequences was negatively correlated with their
repeat unit length and the SSRs with shorter repeat units gained repeats faster than the SSRs with longer repeat units. We
also found that the GC content of poplar sequence significantly correlated with densities of SSRs with uneven repeat unit
lengths (tri-and penta-), but had no significant correlation with densities of SSRs with even repeat unit lengths (di-and
tetra-). In poplar genome, there were evidences that the occurrence of different microsatellites was under selection and the
GC content in SSR sequences was found to significantly relate to the functional importance of microsatellites. 相似文献
992.
Kyungpil Kim Shibo Zhang Keni Jiang Li Cai In-Beum Lee Lewis J Feldman Haiyan Huang 《BMC bioinformatics》2007,8(1):29
Background
Clustering methods are widely used on gene expression data to categorize genes with similar expression profiles. Finding an appropriate (dis)similarity measure is critical to the analysis. In our study, we developed a new measure for clustering the genes when the key factor is the shape of the profile, and when the expression magnitude should also be accounted for in determining the gene relationship. This is achieved by modeling the shape and magnitude parameters separately in a gene expression profile, and then using the estimated shape and magnitude parameters to define a measure in a new feature space. 相似文献993.
The objective of this study was to determine the prevalence, mutual associations, clinical manifestations, and diagnoses associated
with serum autoantibodies, as detected using recently available immunoassays, in patients with autoimmune myositis (AIM).
Sera and clinical data were collected from 100 patients with AIM followed longitudinally. Sera were screened cross-sectionally
for 21 autoantibodies by multiplex addressable laser bead immunoassay, line blot immunoassay, immunoprecipitation of in vitro translated recombinant protein, protein A assisted immunoprecipitation, and enzyme-linked immunosorbent assay. Diagnoses
were determined using the Bohan and Peter classification as well as recently proposed classifications. Relationships between
autoantibodies and clinical manifestations were analyzed by multiple logistic regression. One or more autoantibodies encompassing
19 specificities were present in 80% of the patients. The most common autoantibodies were anti-Ro52 (30% of patients), anti-Ku
(23%), anti-synthetases (22%), anti-U1RNP (15%), and anti-fibrillarin (14%). In the presence of autoantibodies to Ku, synthetases,
U1RNP, fibrillarin, PM-Scl, or scleroderma autoantigens, at least one more autoantibody was detected in the majority of sera
and at least two more autoantibodies in over one-third of sera. The largest number of concurrent autoantibodies was six autoantibodies.
Overall, 44 distinct combinations of autoantibodies were counted. Most autoantibodies were unrestricted to any AIM diagnostic
category. Distinct clinical syndromes and therapeutic responses were associated with anti-Jo-1, anti-fibrillarin, anti-U1RNP,
anti-Ro, anti-Ro52, and autoantibodies to scleroderma autoantigens. We conclude that a significant proportion of AIM patients
are characterized by complex associations of autoantibodies. Certain myositis autoantibodies are markers for distinct overlap
syndromes and predict therapeutic outcomes. The ultimate clinical features, disease course, and response to therapy in a given
AIM patient may be linked to the particular set of associated autoantibodies. These results provide a rationale for patient
profiling and its application to therapeutics, because it cannot be assumed that the B-cell response is the same even in the
majority of patients in a given diagnostic category. 相似文献
994.
Wang T Cong R Yang H Wu MM Luo N Kuang F You SW 《Cellular and molecular neurobiology》2011,31(3):357-364
Transplantation of olfactory ensheathing cells (OECs) becomes one of the promising strategies in restoring lost functions
of injured central nervous system. Elevated level of expressed brain-derived neurotrophic factor (BDNF) was revealed in the
previous studies to be related to the protective effects of OECs on injured cortical and brain stem neurons as well as retinal
ganglion cells (RGCs), but no evidence has been obtained to demonstrate whether transplanted OECs protect injured central
neurons directly by their secreted BDNF. In the present study, the effects of BDNF neutralization on the neuroprotection of
adult OEC-conditioned medium (OEC-CM) on scratch-insulted RGCs were examined. The results showed that OEC-CM protected cultured
RGCs from scratch insult, and neutralization of BDNF by BDNF neutralizing antibody attenuated such neuroprotection of the
medium. It is thus concluded that neurotrophic factors including BDNF secreted by OECs can protect injured OECs in vitro and
BDNF plays a major role in such a protection of OECs. 相似文献
995.
996.
Weide B Eigentler TK Pflugfelder A Leiter U Meier F Bauer J Schmidt D Radny P Pföhler C Garbe C 《Cancer immunology, immunotherapy : CII》2011,60(4):487-493
Systemic high-dose interleukin-2 (IL-2) treatment achieves long-term survival in a subset of advanced patients with melanoma.
As we reported previously, intratumoral IL-2 induced complete local responses in more than 60% of melanoma patients. This
study aimed to analyze the long-term outcome of 72 patients treated in two prior trials. Melanoma patients (49 stage III,
23 stage IV) with injectable metastases received intratumoral IL-2 injections thrice weekly at individually escalated doses
(median duration, 6.5 weeks; median total IL-2 dose, 72 MIU; median number of injected metastases, 10). The observed 2-year
overall survival rates were 95.5% for stage III patients with cutaneous metastases only (stage IIIB), 72% for those with combined
cutaneous and lymph node involvement (stage IIIC), 66.7% for stage IV patients with disease limited to distant soft-tissue
metastases (stage IV M1a), and 9.1% for those with visceral metastases (stage IV M1b and stage IV M1c). Thirty patients who
reported recurrence of unresectable distant metastases subsequently received chemotherapy in the further course of disease
and showed an overall response rate of 36.7% (16.7% complete responses, 20% partial responses). A high total dose of IL-2
and a dacarbazine/temozolomide-based chemotherapy regimen were variables correlated with a clinical response. In conclusion,
patients with cutaneous metastasis without lymph node involvement in stage III and with soft-tissue metastasis without visceral
involvement in stage IV showed unexpected favorable survival rates after intratumoral treatment with IL-2. Furthermore, the
intratumoral IL-2 treatment seemed to be associated with increased complete and partial responses in subsequent chemotherapies. 相似文献
997.
In clinical applications, colonization of metal implants by adhesive and biofilm-forming bacteria not only prolong healing
but create additional healthcare costs for implant revision and antimicrobial treatment. An in vitro assay was established
investigating the antimicrobial surface activity of external fixation pins intended for use in bone fractures and deformities.
Test articles made out of stainless steel and coated with a polymer-containing nanoparticulate silver were compared to non-coated
reference controls out of stainless steel, copper and titanium. Staphylococcus epidermidis, known as a predominant cause for implant-related infections was used as test organism. Test pins and bacteria were incubated
for a period of 20 h found to be sufficient for initiating biofilm formation. After removing non- and low-adherent bacteria
by rinsing, two methods were used to isolate high-adherent (sessile) bacteria from the implant surfaces. Besides shaking the
implants in a solution containing small glass beads, a cytobrush technique was used to mechanically harvest viable bacteria.
Finally, the amount of detached bacteria was determined by plate counts. Several parameters identified to be critical within
the different removal procedures such as the inoculum concentration and the shaking time in the presence of glass beads as
well as time of the cytobrush treatment were analysed. The final test scheme resulted in the use of an inoculum of 105 colony forming units (CFU) per millilitre, ten rinsing steps for the removal of low adherent bacteria and 5 min of shaking
in the presence of glass beads, detaching the high-adherent bacteria. Due to subjective variations impacting the outcome of
the procedure, the cytobrush technique was not favoured and finally rejected. Using the in vitro assay developed, it could
be demonstrated that fixation pins coated with silver show a 3 log step reduction in the number of biofilm-forming bacteria
compared to a non-coated stainless steel or titanium implant. Pins made out of copper showed the highest antimicrobial efficacy,
as the number of detached bacteria was found to be below the detection limit, they served as a positive control within this
test. 相似文献
998.
The binary vector pCAMBIA3300-gpdA-hph-trpC with hygromycin B phosphotransferase (hph) was constructed and transformed into Monascus albidus 9901 by Agrobacterium tumefaciens-mediated transformation, with gene hph as the selective marker. In order to improve the efficiency of A. tumefaciens-mediated transformation in M. albidus 9901, we optimized various factors including concentration of M. albidus 9901 spores, cell density of A. tumefaciens, co-cultivation time, temperature, and acetosyringone concentration. Most transformants of M. albidus 9901 could grow stably on media containing 50 μg ml−1 hygromycin B up to five generations. The presence of hph was identified by PCR. Two transformants H1 and H2 which produced
more Monacolin K than M. albidus 9901 were screened, and the concentration of Monacolin K in the fermented millet by H1 and H2 increased by 42.15% and 40.34%
respectively compared with that produced by M. albidus 9901. 相似文献
999.
The Role of PML in the Nervous System 总被引:1,自引:0,他引:1
The promyeloctic leukemia protein PML is a tumor suppressor that was originally identified due to its involvement in the (15;17)
translocation of acute promyelocytic leukemia. While the majority of early research has focused upon the role of PML in the
pathogenesis of leukemia, more recent evidence has identified important roles for PML in tissues outside the hemopoietic system,
including the central nervous system (CNS). Here, we review recent literature on the role of PML in the CNS, with particular
focus on the processes of neurodevelopment and neurodegeneration, and propose new lines of investigation. 相似文献
1000.
Xu Yu Chen Yao Dong Qi Jian He Wei Zheng Zhang De Li Wang Jin Dong Feng Bing Chun Gan 《World journal of microbiology & biotechnology》2011,27(3):495-503
Fifty-two endophytic fungi strains with different colony morphologies were isolated from stems, leaves and roots of Huperzia serrata (Thunb. ex Murray) Trevis. collected from Bawangling Reserve of Hainan Province in southern China. They were identified mainly
based on rDNA ITS sequences and phylogenetic analysis. The results showed that all strains belonged to four classes, i.e.
Sordariomycetes (92.31%), Dothideomycetes (3.85%), Pezizomycetes (1.92%) and Agaricomycetes (1.92%). Forty-seven strains were identified at the genus level, including Glomerella (Colletotrichum), Hypocrea (Trichoderma), Pleurostoma, Chaetomium, Coniochaeta (Lecythophora), Daldinia, Xylaria, Hypoxylon,
Nodulisporium, Cazia and Phellinus. As to the other five strains, three were identified at the order level and two at the family level, indicating that a great
diversity of fungi taxa exists in H. serrata. Most isolated strains belonged to the genus of Glomerella (Colletotrichum) and Hypoxylon, twenty-one from Glomerella and its anamorph Colletotrichum (42.3% of total isolated strains) and ten from Hypoxylon (19.2% of total isolated strains). Pleurostoma, Chaetomium, Coniochaeta (Lecythophora), Daldinia, Xylaria, Hypoxylon,
Nodulisporium, Cazia and Phellinus were reported as endophytic fungi isolated from H. serrata for the first time. 相似文献