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31.
Summary cDNA complementary to the 3-terminal half of RNA 1 of wheat spindle streak mosaic virus (WSSMV) from Southern France has been cloned and sequenced. One large open reading frame (ORF) of 4 410 nucleotides and a nontranslated region (NTR) of 213 nucleotides at the 3-end excluding the poly(A)-tail were found. Because of the amino acid sequence homology to the polyprotein of barley yellow mosaic virus (BaYMV) RNA 1, the encoded polyprotein of the sequenced region of WSSMV is supposed to comprise the C-terminal part of the putative cytoplasmic inclusion (CI) protein, the nuclear inclusion a (NIa) proteinase, the (NIb) RNA-polymerase and the capsid protein. The first 19 N-terminal amino acids of the capsid protein were determined by direct sequencing of proteins of purified WSSMV particles and confirmed this hypothesis. The deduced capsid protein has 294 amino acids and shows 74% identity with the BaYMV capsid protein sequence. This high sequence homology with BaYMV, in addition to the significant identities with barley mild mosaic virus (BaMMV, 35%) and its marginal homology to capsid protein sequences of aphid and mite-borne potyviruses (22–24%), supports the classification of WSSMV as a distinct member of the genusBaymovirus, familyPotyviridae. 相似文献
32.
Mucolipidoses II is a rare lysosomal storage disorder with autosomal recessive inheritance. There cases with typical clinical
features in early infancy like coarse facial features, severe psychomotor retardation and joint contractures are being reported.
All the cases had no mucopolysacchariduria. These cases had normal values of lysosomal enzymes in leucocytes but markedly
increased values in serum thus confirming mucolipidoses II. Despite the fact that there is no specific treatment, genetic
counselling and prenatal diagnosis is indicated. 相似文献
33.
M S Reddy S R Naik O P Bagga H K Chuttani 《The American journal of clinical nutrition》1980,33(1):77-80
Salivary flow rates by mechanical stimulation with forced spitting method and by chemical stimulation with 10% citric acid were determined in 25 healthy adult subjects with a history of chronic tobacco-betel-lime "quid" chewing and in 25 healthy control adults with no history of chewing. The chewers secreted more saliva as compared to nonchewers on chemical, but not on mechanical stimulation. The salivary amylase, potassium, and sodium levels were lower in chewers, but the reductions of the first two components only were significant. These reductions were thought to be due to increased salivary flow with its dilutional effect. There was no difference between the two groups with respect to salivary pH. The salivary flow rates by either method had significant positive correlation with the duration of chewing, but not with the amount of tobacco chewed. Salivary potassium was inversely correlated with the amount of tobacco chewed. It was concluded that chronic tobacco-betel-lime quid chewing induces excessive secretion of more watery saliva leading to a concomitant decrease in enzyme and electrolyte content. One or more of the following factors were considered to be operating in causing increased salivary flow in chewers effect of nicotine or tobacco on other constituents of the quid, chronic salivary gland hyperplasia, or chronic hypertrophy of the muscles of mastication. 相似文献
34.
A. Greenough B. Yuksel S. Naik P. Cheeseman K. H. Nicolaides 《European journal of pediatrics》1997,156(7):550-552
Neonatal respiratory difficulties are increased following second trimester amniocentesis. In preterm, prolonged rupture of
the membranes, respiratory outcome is particularly poor when rupture occurs in the first trimester. It therefore seems likely
that first trimester/early amniocentesis (EA) would be associated with severe respiratory problems necessitating a high neonatal
intensive care unit (NICU) admission rate. To test that hypothesis, the requirement for admission to the NICU of 278 infants
whose mothers had undergone EA, 262 whose mothers had undergone chorion villus sampling (CVS group) and 264 controls whose
mothers had undergone no invasive procedures were reviewed as were their diagnoses if they needed admission. There was no
significant difference in the mode of delivery, gestational age or gender distribution of the three groups and the median
maternal age of the EA and CVS groups was similar. Nineteen EA, eight CVS and five control infants required admission to the
NICU (EA versus controls, P < 0.01; EA versus CVS plus controls, P < 0.005). Nine EA, one CVS and four control infants had suffered respiratory problems
(EA versus CVS P < 0.05). Logistic regression analysis demonstrated that immaturity and EA were significantly associated with
a requirement for NICU admission. We conclude infants whose mothers have undergone EA may be at increased risk for NICU admission,
this is partly due to respiratory problems but the association is uncommon.
Received: 1 August 1996 / Accepted: 12 December 1996 相似文献
35.
Distribution of protein kinase Mzeta and the complete protein kinase C isoform family in rat brain 总被引:3,自引:0,他引:3
Naik MU Benedikz E Hernandez I Libien J Hrabe J Valsamis M Dow-Edwards D Osman M Sacktor TC 《The Journal of comparative neurology》2000,426(2):243-258
Protein kinase C (PKC) is a multigene family of at least ten isoforms, nine of which are expressed in brain (alpha, betaI, betaII, gamma, delta, straightepsilon, eta, zeta, iota/lambda). Our previous studies have shown that many of these PKCs participate in synaptic plasticity in the CA1 region of the hippocampus. Multiple isoforms are transiently activated in the induction phase of long-term potentiation (LTP). In contrast, a single species, zeta, is persistently activated during the maintenance phase of LTP through the formation of an independent, constitutively active catalytic domain, protein kinase Mzeta (PKMzeta). In this study, we used immunoblot and immunocytochemical techniques with isoform-specific antisera to examine the distribution of the complete family of PKC isozymes and PKMzeta in rat brain. Each form of PKC showed a widespread distribution in the brain with a distinct regional pattern of high and low levels of expression. PKMzeta, the predominant form of PKM in brain, had high levels in hippocampus, frontal and occipital cortex, striatum, and hypothalamus. In the hippocampus, each isoform was expressed in a characteristic pattern, with zeta prominent in the CA1 stratum radiatum. These results suggest that the compartmentalization of PKC isoforms in neurons may contribute to their function, with the location of PKMzeta prominent in areas notable for long-term synaptic plasticity. 相似文献
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The effect of crystallization process speed on the morphology of solution-processed methyl ammonium lead iodide (MAPbI3) thin films is investigated. Crystallization speed is controlled by varying the number of annealing steps, temperature, and resting time between steps. The resting period allows solvent-controlled growth (SCG) in which crystallization progresses slowly via an intermediate phase—during which solvents slowly evaporate away from the films. SCG results in fewer residues, fewer pinholes, and larger grain sizes. Consequently, thin-film transistors with SCG MAPbI3 exhibit smaller hysteresis in their current-voltage characteristics than those without, demonstrating the benefits of SCG toward hysteresis-free perovskite devices. 相似文献
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