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11.
12.
G. Tillotson M. Arora M. Robbins J. Holton 《European journal of clinical microbiology & infectious diseases》1988,7(5):675-678
A total of 170 strains ofCorynebacterium jeikeium and 23 strains ofCorynebacterium group D2 were examined in three British laboratories using the API 20 Strep identification system and three supplementary tests (catalase production, urease production and nitrate reduction). The isolates were collected from clinical specimens in various laboratories over a three-year period. The two species produced consistent reactions in these tests after 24 h. Two tests were highly discriminatory, with positive reactions for ribose fermentation seen forCorynebacterium jeikeium while urease production was observed withCorynebacterium group D2. This method allows routine clinical laboratories to rapidly identify these emerging pathogens. 相似文献
13.
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
14.
Sperm quality in Hodgkin's disease versus non-Hodgkin's lymphoma 总被引:3,自引:4,他引:3
Botchan A; Hauser R; Gamzu R; Yogev L; Lessing JB; Paz G; Yavetz H 《Human reproduction (Oxford, England)》1997,12(1):73-76
The study was conducted to determine the deleterious effect of lymphoma
disease on spermatogenesis and to evaluate the possibility that the disease
is mediated primarily by inherent mechanisms in Hodgkin's disease and
non-Hodgkin's lymphoma patients. A total of 89 patients with lymphoma
disease (Hodgkin's and non-Hodgkin's) were referred for sperm preservation
prior to adjuvant treatments. A comparison was made of pre- and post-thaw
sperm quality between lymphoma patients and healthy volunteers who applied
for sperm donation. This was followed by further assessment of the
differences between patients with Hodgkin's disease and non-Hodgkin's
lymphoma in terms of sperm variables, clinical parameters and blood hormone
concentrations. It was found that patients with lymphoma disease had
significantly impaired pre-freeze and post-thaw sperm quality compared with
that of healthy volunteers. Patients with non-Hodgkin's lymphoma had
spermatozoa of higher quality than patients with Hodgkin's disease. No
differences were found in the clinical or hormonal parameters between these
two groups. As expected, reduced testicular size and abnormal testicular
consistency were correlated with decreased sperm quality. The mere presence
of cancer disease has a direct negative effect on spermatogenesis, which is
probably not related to incidental side-effects. A variable degree of
impairment should be expected with different categories of cancer.
相似文献
15.
16.
Molecular heterogeneity at the phenylalanine hydroxylase locus in the population of the south-west of England.
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The phenylalanine hydroxylase gene locus has been studied in 35 independent phenylketonuric families in the south-west of England using RFLP haplotype patterns and allele specific oligonucleotide probes. Haplotype 3 was the most common pattern on mutant chromosomes and there was strict linkage disequilibrium between this haplotype and the splice mutation in exon 12. The R408W mutation in exon 12 occurred on both haplotypes 1 and 2. The R126Q mutation in exon 7 was found only on a rare haplotype 28 pattern. No gene carried the R158Q mutation. More than 60% of mutant genes did not carry these four mutations which were originally described in other European populations. We suggest that the splice mutation arose as a single event and spread throughout northern Europe by population migration and admixture. In addition, we believe the haplotype/mutation associations seen in our population are a reflection of the mixed ancestry of the inhabitants of the British Isles. 相似文献
17.
The experience from three different European centres with the prenatal diagnosis of galactose-1-phosphate-uridyltransferase (GALT) deficiency is presented and the question whether or not there is a need for prenatal diagnosis of this disorder is discussed. Most prenatal diagnoses (n=50) have been performed by assay of GALT activity in cultured amniotic fluid cells. The assay used is reliable and clearly distinguishes homozygous affected fetuses (n=11; 0%–2.3% of mean control enzyme activity) from non-(homozygous)-affected fetuses. The GALT assay for cultured amniocytes was adapted to assay the enzyme directly in chorionic villi. The experience with chorionic villi comprises 23 cases with 5 affected fetuses (0%–4.2% of mean control enzyme activity). In 36 cases galactitol was determined in amniotic fluid supernatant by gas chromatography-mass spectrometry. This method also differentiated affected (n=11; galactitol 5.9–10.6 mol/l) and unaffected pregnancies (galactitol 0.23–1.6 mol/l) clearly and has the advantage of providing a result within a day or two after amniocentesis. Prenatal diagnosis of galactosemia is undertaken rarely and sometimes for the wrong reasons, but it should perhaps be considered more seriously until better methods of treatment are established. 相似文献
18.
We report the case of a chess player with superior premorbid cognitive function who presented to the Cognitive Disorders clinic at the National Hospital for Neurology and Neurosurgery with a 2-year history of symptoms of possible memory loss. Initially the MRI scan appearance was within normal limits and his cognitive scores inside the normal range; subsequently his cognitive function deteriorated and he fulfilled criteria for Mild Cognitive Impairment (MCI) two years later. Unexpectedly he died of an unrelated illness seven months later and post mortem examination of the brain was carried out, revealing advanced Alzheimer’s disease (CERAD definite and NIA-Regan Institute high likelihood). This case highlights the difficulties encountered in assessing patients with superior premorbid function in the early stages of Alzheimer’s disease, and reveals the value of serial MRI and neuropsychological assessment in detecting and monitoring early neurodegenerative disease. 相似文献
19.
Luke A. Massey MRCP Caroline Micallef MD FRCR Dominic C. Paviour PhD Sean S. O'Sullivan PhD MRCPI Helen Ling BScMed BMBS MSc David R. Williams PhD Constantinos Kallis PhD Janice L. Holton PhD FRCPath Tamas Revesz MD FRCPath David J. Burn MD FRCP Tarek Yousry Dr med Habil FRCR Andrew J. Lees MD FRCP Nick C. Fox PhD FRCP Hans R. Jäger MD FRCR 《Movement disorders》2012,27(14):1754-1762
Conventional magnetic resonance imaging (cMRI) is often used to aid the diagnosis of progressive supranuclear palsy (PSP) and multiple system atrophy (MSA), but its ability to predict the histopathological diagnosis has not been systematically studied. cMRI from 48 neuropathologically confirmed cases, including PSP (n = 22), MSA (n = 13), Parkinson's disease (PD) (n = 7), and corticobasal degeneration (n = 6), and controls (n = 9) were assessed blinded to clinical details and systematically rated for reported abnormalities. Clinical diagnosis and macroscopic postmortem findings were retrospectively assessed. Radiological assessment of MRI was correct in 16 of 22 (72.7%) PSP cases and 10 of 13 (76.9%) MSA cases with substantial interrater agreement (Cohen's kappa 0.708; P < .001); no PSP case was misclassified as MSA or vice versa. MRI was less sensitive but more specific than clinical diagnosis in PSP and both more sensitive and specific than clinical diagnosis in MSA. The “hummingbird” and “morning glory” signs were highly specific for PSP, and “the middle cerebellar peduncle sign” and “hot cross bun” for MSA, but sensitivity was lower (up to 68.4%) and characteristic findings may not be present even at autopsy. cMRI, clinical diagnosis, and macroscopic examination at postmortem have similar sensitivity and specificity in predicting a neuropathological diagnosis. We have validated specific radiological signs in pathologically confirmed PSP and MSA. However, the low sensitivity of these and macroscopic findings at autopsy suggest a need for imaging techniques sensitive to microstructural abnormalities without regional atrophy. © 2012 Movement Disorder Society 相似文献
20.