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971.
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
972.
973.
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
974.
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
975.
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
976.
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
977.
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
978.
Cyanobacteria and chloroflexi-dominated hypolithic colonization of quartz at the hyper-arid core of the Atacama Desert,Chile 总被引:1,自引:0,他引:1
Lacap DC Warren-Rhodes KA McKay CP Pointing SB 《Extremophiles : life under extreme conditions》2011,15(1):31-38
Quartz stones are ubiquitous in deserts and are a substrate for hypoliths, microbial colonists of the underside of such stones.
These hypoliths thrive where extreme temperature and moisture stress limit the occurrence of higher plant and animal life.
Several studies have reported the occurrence of green hypolithic colonization dominated by cyanobacteria. Here, we describe
a novel red hypolithic colonization from Yungay, at the hyper-arid core of the Atacama Desert in Chile. Comparative analysis
of green and red hypoliths from this site revealed markedly different microbial community structure as revealed by 16S rRNA
gene clone libraries. Green hypoliths were dominated by cyanobacteria (Chroococcidiopsis and Nostocales phylotypes), whilst the red hypolith was dominated by a taxonomically diverse group of chloroflexi. Heterotrophic
phylotypes common to all hypoliths were affiliated largely to desiccation-tolerant taxa within the Actinobacteria and Deinococci.
Alphaproteobacterial phylotypes that affiliated with nitrogen-fixing taxa were unique to green hypoliths, whilst Gemmatimonadetes
phylotypes occurred only on red hypolithon. Other heterotrophic phyla recovered with very low frequency were assumed to represent
functionally relatively unimportant taxa. 相似文献
979.
Supattra Treerattrakool Sakol Panyim Apinunt Udomkit 《Marine biotechnology (New York, N.Y.)》2011,13(2):163-169
Ovarian maturation in crustacean is under the control of gonad-inhibiting hormone (GIH); a neuropeptide secreted from X-organ
sinus gland complex in eyestalks. Unilateral eyestalk ablation that partially destroys GIH source is therefore a general practice
in Penaeus monodon hatchery to induce ovarian maturation and spawning. Our previous report showed that silencing of GIH expression by GIH-specific double-stranded RNA (GIH-dsRNA) resulted in an increased expression level of vitellogenin in P. monodon, thus suggesting that GIH-dsRNA could be an alternative method to induce ovarian maturation in female P. monodon broodstock. In this study, we further demonstrated that a single injection of GIH-dsRNA into previtellogenic female P. monodon at the concentration of 3 μg GIH-dsRNA per gram body weight of shrimp was able to inhibit GIH expression for a minimum of 30 days. This dsRNA-mediated GIH silencing led to ovarian maturation and eventual spawning in both domesticated and wild female broodstock, particularly with
a comparable effect to eyestalk ablation in wild shrimp. This is the first report that demonstrates a potential strategy to
induce ovarian maturation in female P. monodon broodstock by GIH-dsRNA and thus provides a possible substitute for the cruel and detrimental eyestalk ablation practice. 相似文献
980.
Kapetanovic MC Lindqvist E Algulin J Jonsson K Saxne T Eberhardt K Geborek P 《Arthritis research & therapy》2011,13(1):R31