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41.
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The mean concentrations of immunoreactive substance P in cerebrospinal fluid (CSF) of 10 fetuses (gestational age 11-20 weeks) were 22.7 +/- 8.3 pmol/ml, compared with 250.0 +/- 28.2 fmol/ml in premature babies (gestational age 25-31.5 weeks, n = 8), 141.0 +/- 14.2 fmol/ml in full term newborn babies (n = 5), 50.0 +/- 2.3 fmol/ml in children (age 1-6 years, n = 6), and 9.5 +/- 1.5 fmol/ml in 5 adults. The differences between successive age groups were all statistically significant. The high concentration of substance P in human CSF in the early stages of development and its continuous decline towards maturity encourages the idea that substance P plays a role in neuro-development. 相似文献
43.
H Ishiko N Takeda K Miyamura N Kato M Tanimura K H Lin M Yin-Murphy J S Tam G F Mu S Yamazaki 《Virology》1992,187(2):748-759
Nucleotide substitutions in the viral-encoded proteinase 3C (3Cpro) region (549 nucleotides) of the RNA genome of a coxsackievirus A24 variant (CA24v), one of the agents causing acute hemorrhagic conjunctivitis (AHC), were studied using 32 isolates collected from the Eastern hemisphere in 1970-1989. Based on regression analysis of nucleotide differences among isolates, the nucleotide substitution rate of CA24v 3Cpro was estimated to be 3.7 x 10(-3)/nucleotide/year. A phylogenetic tree constructed by the modified unweighted pair group method using arithmetic averages (UPGMA) indicated that CA24v had evolved from a common ancestor which appeared in one focal place in November 1963 +/- 21 months, about 7 years before the first isolation of CA24v in Singapore. The tree also revealed that all the recent epidemic isolates in 1985-1989 including Asian and Ghanian strains diverged from each other after 1981. This finding is consistent with the evidence that AHC due to CA24v had been confined to Southeast Asia and the Indian subcontinent until 1985, then suddenly and explosively spread to other areas where no CA24v isolations had been reported. 相似文献
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Counter-immunoelectro-osmophoresis for the detection of infantile gastroenteritis virus (orbi-group) antigen and antibody. 总被引:7,自引:2,他引:7 下载免费PDF全文
P J Middleton M Petric C M Hewitt M T Szymanski J S Tam 《Journal of clinical pathology》1976,29(3):191-197
A moderatley sensitive, rapid, and economical test scheme for the detection of infantile gastroenteritis virus (IGV) in stool or antibody in serum has been developed and evaluated. The test scheme with minor modifications was an adaptation of a counter-immunoelectro-osmophoresis system we once used for the detection of hepatitis B antigen. Large numbers of stool samples may be screened during half a working day for the presence of IGV using reference antiserum to IGV prepared in guinea-pigs. Serological studies of a diagnostic but not epidemiological nature may also be performed with equal facility by this same test scheme using highly purified IGV antigen derived from stool. 相似文献
48.
Monoclonal antibodies to the major nonstructural nuclear protein of minute virus of mice. 总被引:1,自引:0,他引:1
Monoclonal antibodies were raised against a bacterial fusion protein containing amino acids 364 to 623 of the major nonstructural protein, NS-1, of minute virus of mice (MVMp), an autonomous parvovirus. By immunoblot analyses, these antibodies all recognized an 83-kDa protein in MVM-infected mouse fibroblast cells. Indirect immunofluorescence studies showed that five of the six react against a nuclear protein in MVM-infected mouse cells resulting in discrete foci of fluorescence. These foci do not correspond with the nucleoli, the site of MVM DNA replication. The epitopes of the antibodies were mapped using carboxy-terminal deleted bacterial fusion proteins derived from the plasmid encoding the original antigen and showed that four distinct epitopes were recognized by the different antibodies. A 25-amino-acid peptide was used in competition ELISAs to confirm the location of the epitope recognized by two antibodies CE10 and AC6. Preliminary characterization of an NS-1/NS-2 fusion protein synthesized in insect cells using a baculovirus expression vector showed that this fusion protein is also localized within the nucleus; however, in contrast, the full-length NS-1 polypeptide is located within the cytoplasm. 相似文献
49.
Replicative MCM7 protein as a proliferation marker in endometrial carcinoma: a tissue microarray and clinicopathological analysis 总被引:3,自引:0,他引:3
Li SS Xue WC Khoo US Ngan HY Chan KY Tam IY Chiu PM Ip PP Tam KF Cheung AN 《Histopathology》2005,46(3):307-313
AIMS: To assess, in tissue microarray (TMA), the proliferative activity of endometrial carcinoma using one of the minichromosome maintenance (MCM) proteins (MCM7), and to explore its potential value for prognosis. MCM proteins are essential for eukaryotic DNA replication and have recently been used to define the proliferative compartments in human tissues. METHODS AND RESULTS: Immunohistochemistry for MCM7 and Ki67 was performed on TMAs constructed from 212 cases of endometrial carcinoma. MCM7 and Ki67 expression was quantified according to the extent of nuclear staining. An analysis was carried out of the association between MCM7 expression and that of Ki67 and the clinicopathological characteristics of endometrial carcinoma. MCM7 and Ki67 immunoreactivity was clearly evident in the nuclei of tumour cells. MCM7 and Ki67 labelling indices in endometrial carcinomas correlated with each other (P < 0.001). A significant correlation existed between the MCM7 labelling index and histological grade (P = 0.008) and patients' age at diagnosis (P < 0.001). Well-differentiated carcinomas and younger patients had a lower MCM7 index. Poor survival was observed in patients with endometrial carcinoma with a high MCM7 index (P = 0.03) and MCM7 was found to be an independent prognostic factor by multivariate analysis (P = 0.04). The Ki67 labelling index correlated with histological grade (P = 0.01) but had no significant prognostic impact (P = 0.50). CONCLUSIONS: In this TMA study on endometrial carcinoma, MCM7 was found to be a more reliable and useful marker than Ki67 in assessing tumour proliferation and in the prognosis of patients. 相似文献
50.
An empirical model is presented for hepatic elimination of substrates which treats the liver as a series of compartments. The number of compartments serves as an adjustable parameter and determines the effect of changes in blood flow on elimination. By allowing variable dependence of clearance on blood flow, the model serves as a bridge between the extreme cases of venous equilibrium (the "well-stirred" model) and the "parallel-tube" model. The adjustable parameter in the model can be determined by measuring the clearance at different rates of blood flow, or at different extents of binding of the substrate to blood components. Examples are given for steady state elimination of several different substrates with linear and nonlinear elimination kinetics. 相似文献