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61.
Magdy S. Aly Paola Dal Cin Herman Van Den Berghe Wim Van De Voorde Hein Van Poppel Filip Ameye Luc Baert 《Genes, chromosomes & cancer》1994,9(4):227-233
We combined conventional cytogenetic analysis and fluorescence in situ hybridization of short-term cultures of 28 samples from benign prostatic hyperplasia. Lou of the Y chromosome was the most common chromosome change, followed by trisomy 7. Trisomy 7, however, may be unrelated to the origin of benign prostate hyperplasia, in which the only and not very specific change seems to be the loss of the Y chromosome. Genes Chrom Cancer 9:227-233 (1594). © 1994 Wiley-Liss, Inc. 相似文献
62.
Mahadevan Mani S.; Amemiya Chris; Jansen Gert; Sabourin Luc; Baird Stephen; Neville Catherine E.; Wormskamp Nicole; Segers Bart; Batzer Mark; Lamerdin Jane; de Jong Peter; Wieringa Be; Korneluk Robert G. 《Human molecular genetics》1993,2(3):299-304
The mutation causing myotonic dystrophy (DM) has recently beenidentified as an unstable CTG trinucleotide repeat located inthe 3' untranslated region of a gene encoding for a proteinwith putative serine-threonine protein kinase activity. In thisreport we present the genomic sequences of the human and murineDM kinase gene. A comparison of these sequences with each otherand with known cDNA sequences from both species, led us to predicta translation initiation codon, as well as determine the organizationof the DM kinase gene. Several polymorphisms within the humanDM kinase gene have been identified, and PCR assays to detecttwo of these are described. The complete sequence and characterizationof the structure of the DM kinase gene, as well as the identificationof novel polymorphisms within the gene, represent an importantstep in a further understanding of the genetics of myotonicdystrophy and the molecular biology of the gene. 相似文献
63.
Joost Dekker Bob Boot Luc H. V. van der Woude J. W. J. Bijlsma 《Journal of behavioral medicine》1992,15(2):189-214
Pain and disability are cardinal symptoms in osteoarthritis. The literature is reviewed in order to identify causes of these symptoms at the articular, kinesiological, and psychological level. It is concluded that pain and disability are associated with degeneration of cartilage and bone (articular level), with muscle weakness and limitations in joint motion (kinesiological level), and with anxiety, coping style, attentional focus on symptoms, and possibly depression (psychological level). Biobehavioral mechanisms of pain and disability which explain the observed associations are described and the empirical evidence for these mechanisms is evaluated. Methodological and conceptual deficiencies in the research reviewed are pointed out and suggestions for further research are given. 相似文献
64.
Begovac J Mihaljevic I Perrin L 《The New England journal of medicine》2004,351(21):2232-5; author reply 2232-5
65.
We analyzed the kinetics of heart rate (HR) response during incremental treadmill exercise in thirteen master runners (62 +/- 1 yr). The HR/running speed (HR/S) relationship showed the existence of a point of downward deflection (HR(d)) in only approximately 31% of the subjects. Resting echocardiographic evaluations showed similar heart dimensions in all of the subjects. In conclusion, HR does not seem to show a curvilinear response (downward deflection) in most aged athletes. 相似文献
66.
Rodrigo-Angulo ML Rodríguez-Veiga E Reinoso-Suárez F 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》2005,160(3):334-343
The ventral part of the cat oral pontine reticular nucleus (vRPO) is the site in which microinjections of small dose and volume of cholinergic agonists produce long-lasting rapid eye movement sleep with short latency. The present study determined the precise location and proportions of the cholinergic brainstem neuronal population that projects to the vRPO using a double-labeling method that combines the neuronal tracer horseradish peroxidase–wheat germ agglutinin with choline acetyltransferase immunocytochemistry in cats. Our results show that 88.9% of the double-labeled neurons in the brainstem were located, noticeably bilaterally, in the cholinergic structures of the pontine tegmentum. These neurons occupied not only the pedunculopontine and laterodorsal tegmental nuclei, which have been described to project to other pontine tegmentum structures, but also the locus ceruleus complex principally the locus ceruleus and peri-, and the parabrachial nuclei. Most double-labeled neurons were found in the pedunculopontine tegmental nucleus and locus ceruleus complex and, much less abundantly, in the laterodorsal tegmental nucleus and the parabrachial nuclei. The proportions of these neurons among all choline acetyltransferase positive neurons within each structure were highest in the locus ceruleus complex, followed in descending order by the pedunculopontine and laterodorsal tegmental nuclei and then, the parabrachial nuclei. The remaining 11.1% of double-labeled neurons were found bilaterally in other cholinergic brainstem structures: around the oculomotor, facial and masticatory nuclei, the caudal pontine tegmentum and the praepositus hypoglossi nucleus. The disperse origins of the cholinergic neurons projecting to the vRPO, in addition to the abundant noncholinergic afferents to this nucleus may indicate that cholinergic stimulation is not the only or even the most decisive event in the generation of REM sleep. 相似文献
67.
The P-selectin gene is highly polymorphic: reduced frequency of the Pro715 allele carriers in patients with myocardial infarction 总被引:10,自引:3,他引:10
Herrmann SM; Ricard S; Nicaud V; Mallet C; Evans A; Ruidavets JB; Arveiler D; Luc G; Cambien F 《Human molecular genetics》1998,7(8):1277-1284
P-selectin is an adhesion molecule, expressed at the surface of activated
cells, that mediates the interaction of activated endothelial cells or
platelets with leukocytes. P-selectin expression is increased in
atherosclerotic plaques, and high plasma levels of this molecule have been
observed in patients with unstable angina. We investigated the P-selectin
gene as a possible candidate for myocardial infarction (MI). The P-selectin
gene is situated on chromosome 1q21-q24, spans >50 kb and contains 17
exons. The sequences of the 5'-flanking region and exons of 40 alleles from
patients with MI were screened for polymorphisms using polymerase chain
reaction/single-strand conformation polymorphism (PCR-SSCP) and sequencing.
Thirteen polymorphisms were identified: five in the 5'-flanking and eight
in the exonic sequences. Four polymorphisms (Ser290Asn, Asn562Asp,
Leu599Val and Thr715Pro) predicted a change in the amino acid sequence of
the P- selectin protein. All P-selectin polymorphisms as well as a common
E- selectin polymorphism, Ser128Arg which has been reported as being
associated with an increased risk of premature coronary heart disease
(CHD), and is in tight linkage disequilibrium with several P-selectin
polymorphisms, were investigated in 647 patients with MI and 758 control
subjects from four regions of France and Northern Ireland (the ECTIM
study). The entire set of P-selectin polymorphisms provided a
heterozygosity of 91%. The polymorphisms were tightly associated with one
another and displayed patterns of linkage disequilibrium suggesting the
existence of highly conserved ancestral haplotypes. The five polymorphisms
in the 5'-flanking region of the gene were unrelated to MI or any relevant
phenotype measured in the ECTIM study. We inferred that the four missense
variants identified in the coding region predicted eight common forms of
the P-selectin protein. The Pro715 allele which characterizes one of these
forms was less frequent in France than in Northern Ireland ( P < 0.002)
and in cases than in controls ( P < 0.002; P < 0.02 after correction
for the number of tests). We conclude that the P-selectin gene is highly
polymorphic and hypothesize that the Pro715 variant may be protective for
MI. Whether this variant affects the properties of the P-selectin protein
in a way which is compatible with this hypothesis needs to be checked
experimentally.
相似文献
68.
Many physiological markers vary similarly during training and overtraining. This is the case for the blood lactate concentration
([La−]b), since a right shift of the lactate curve is to be expected in both conditions. We examined the possibility of separating
the changes in training from those of overtraining by dividing [La−]b by the rating of perceived exertion ([La−]b/RPE) or by converting [La−]b into a percentage of the peak blood lactate concentration ([La−]b,peak). Ten experienced endurance athletes increased their usual amount of training by 100% within 4 weeks. An incremental test
and a time trial were performed before (baseline) and after this period of overtraining, and after 2 weeks of recovery (REC).
The [La−]b and RPE were measured during the recovery of each stage of the incremental test. We diagnosed overtraining in seven athletes,
using both physiological and psychological criteria. We found a decrease in mean [La−]b,peak from baseline to REC [9.64 (SD 1.17), 8.16 (SD 1.31) and 7.69 (SD 1.84) mmol · l−1, for the three tests, respectively; P < 0.05] and a right shift of the lactate curve. Above 90% of maximal aerobic speed (MAS) there was a decrease of mean [La−]b/RPE from baseline to REC [at 100% of MAS of 105.41 (SD 17.48), 84.61 (SD 12.56) and 81.03 (SD 22.64) arbitrary units, in
the three tests, respectively; P < 0.05), but no difference in RPE, its variability accounting for less than 25% of the variability of [La−]b/RPE (r=0.49). Consequently, [La−]b/RPE provides little additional information compared to [La−]b alone. Expressing [La−]b as a %[La−]b,peak resulted in a suppression of the right shift of the lactate curve, suggesting it was primarily the consequence of a decreased
production of lactate by the muscle. Since the right shift of the curve induced by optimal training is a result of improved
lactate utilization, the main difference between the two conditions is the decrease of [La−]b,peak during overtraining. We propose retaining it as a marker of overtraining for long duration events, and repeating its measurement
after a sufficient period of rest to make the distinction with overreaching.
Accepted: 26 September 2000 相似文献
69.
Anja Kimpe Annemie Decostere Margo Baele Luc A Devriese Freddy Haesebrouck 《Avian pathology》2004,33(3):310-313
Faecal samples from 50 pigeons all originating from different lofts were screened for the presence of macrolide and lincosamide (ML)-resistant isolates of Streptococcus gallolyticus and Enterococcus columbae by plating the samples onto selective media. Sixty-eight ML-resistant E. columbae strains were recovered from the faecal samples of 29 animals. Two of these samples also harboured ML-resistant S. gallolyticus strains. The erm(B) gene was detected in 58 E. columbae and in five S. gallolyticus isolates. Four of these E. columbae isolates also carried the mef(A) gene. Five E. columbae strains possessed the mef(A) gene in the absence of erm(B). On the basis of the sequence of the complete erm(B) gene, 10 E. columbae isolates clustered together in six groups. In two of these isolates, the erm(B) gene sequence was identical to that of S. gallolyticus strains, indicating that exchange of resistance genes might occur between pathogenic and non-pathogenic bacterial species belonging to the pigeon's intestinal flora. 相似文献
70.
Honey K Benlagha K Beers C Forbush K Teyton L Kleijmeer MJ Rudensky AY Bendelac A 《Nature immunology》2002,3(11):1069-1074
CD1d antigen presentation to natural killer T (NKT) cells expressing the semi-invariant T cell receptor V(alpha)14J(alpha)18 requires CD1d trafficking through endosomal compartments; however, the endosomal events remain undefined. We show that mice lacking the endosomal protease cathepsin L (catL) have greatly reduced numbers of V(alpha)14(+)NK1.1(+) T cells. In addition, catL expression in thymocytes is critical not only for selection of these cells in vivo but also for stimulation of V(alpha)14(+)NK1.1(+) T cells in vitro. CD1d cell-surface expression and intracellular localization appear normal in catL-deficient thymocytes, as does the lysosomal morphology; this implies a specific role for catL in regulating presentation of natural CD1d ligands mediating V(alpha)14(+)NK1.1(+) T cell selection. These data implicate lysosomal proteases as key regulators of not only classical major histocompatibility complex class II antigen presentation but also nonclassical CD1d presentation. 相似文献