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1.
M. L. Garrè V. Capra E. Di Battista L. Giampietri P. Nozza A. Raso A. Pezzolo A. Rossi C. Milanaccio M. Pavanello A. Naselli 《Child's nervous system》2007,23(2):219-223
Objects Genetic syndromes associated with ependymoma are uncommon, with the exception of NF2. We describe two cases of ependymoma
presenting with Klinefelter’s Syndrome (KS) as co-morbid condition.
Materials and methods The first patient was diagnosed for KS during pregnancy; he also presented a thyroid agenesis and a deficit of methyltetrahydrofolate
reductase (MTHFR); at 30 months of age he was operated on for a grade II ependymoma of IV ventricle; after a multiple-stage
surgery, he underwent oral chemotherapy and stereotactic radiotherapy, but after 15 months he presented a local recurrence
and died. The second patient was diagnosed for KS at the age of 16 months; at 10 years of age, due to back pain, he underwent
an MRI, which showed a cauda equine tumor. He underwent surgery and radiotherapy. Histology was of mixopapillary ependymoma.
Conclusion In a review of literature, various neoplasms have been described in association with KS. To our knowledge, these are the first
two cases reported of ependymoma associated to KS. A retrospective study of 44 monoinstitutional ependymoma cases demonstrated
association with genetic syndromes in 22%. 相似文献
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E M Mandel H E Rockette J L Paradise C D Bluestone R J Nozza 《The Pediatric infectious disease journal》1991,10(12):899-906
We randomly assigned children with otitis media with effusion to receive either erythromycin-sulfisoxazole, cefaclor, amoxicillin or placebo for a 2-week period, primarily to determine whether either erythromycin-sulfisoxazole or cefaclor would have greater short term efficacy than that found previously for amoxicillin, and secondarily to supplement earlier data on outcomes in placebo-treated subjects. Interim analyses showed no statistically significant (P less than 0.05) differences between the three antimicrobial treatment groups in the primary outcome measures, i.e. the prevalence of middle-ear effusion 2 and 4 weeks after entry, and indicated that postulated differences favoring the erythromycin-sulfisoxazole and cefaclor groups over the amoxicillin group were unlikely to be found even if the originally calculated sample size were attained. Subject accrual was therefore terminated. Final analysis showed no significant between-group differences in other outcome measures as well. In antimicrobial vs. placebo comparisons neither erythromycin-sulfisoxazole nor cefaclor gave more favorable outcomes than placebo, whereas more children were effusion-free in the amoxicillin group than in the placebo group at 2 weeks (31.6% vs. 14.1%, P = 0.007), but not at 4 weeks. We conclude that when antimicrobial treatment for otitis media with effusion is deemed advisable, neither erythromycin-sulfisoxazole nor cefaclor should replace amoxicillin as first line treatment. 相似文献
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Competitive control of the self-renewing T cell repertoire 总被引:1,自引:0,他引:1
We develop a mathematical model for the self-renewing part of the T cell
repertoire. Assuming that self-renewing T cells have to be stimulated by
immunogenic MHC-peptide complexes presented on the surfaces of
antigen-presenting cells, we derive a model of T cell growth in which
competition for MHC-peptide complexes limits T cell clone sizes and
regulates the total number of self-renewing T cells in the animal. We show
that for a sufficient diversity and/or degree of cross-reactivity, the
total T cell number hardly depends upon the diversity of the T cell
repertoire or the diversity of the set of presented peptides. Conversely,
for repertoires of lower diversity and/or cross-reactivity, steady-state
total T cell numbers may be limited by the diversity of the T cells. This
provides a possible explanation for the limited repertoire expansion in
some, but not all, mouse T cell re-constitution experiments. We suggest
that the competitive interactions described by our model underlie the
normal T cells numbers observed in transgenic mice, germ-free mice and
various knockout mice.
相似文献
8.
Localization of a gene for otosclerosis to chromosome 15q25-q26 总被引:5,自引:0,他引:5
Tomek MS; Brown MR; Mani SR; Ramesh A; Srisailapathy CR; Coucke P; Zbar RI; Bell AM; McGuirt WT; Fukushima K; Willems PJ; Van Camp G; Smith RJ 《Human molecular genetics》1998,7(2):285-290
Among white adults otosclerosis is the single most common cause of hearing
impairment. Although the genetics of this disease are controversial, the
majority of studies indicate autosomal dominant inheritance with reduced
penetrance. We studied a large multi- generational family in which
otosclerosis has been inherited in an autosomal dominant pattern. Five of16
affected persons have surgically confirmed otosclerosis; the remaining nine
have a conductive hearing loss but have not undergone corrective surgery.
To locate the disease- causing gene we completed genetic linkage analysis
using short tandem repeat polymorphisms (STRPs) distributed over the entire
genome. Multipoint linkage analysis showed that only one genomic region, on
chromosome 15q, generated a lod score >2.0. Additional STRPs were typed
in this area, resulting in a lod score of 3.4. STRPs FES (centromeric) and
D15S657 (telomeric) flank the 14. 5 cM region that contains an otosclerosis
gene.
相似文献
9.
IMPT1, an imprinted gene similar to polyspecific transporter and multi- drug resistance genes 总被引:5,自引:1,他引:5
Dao D; Frank D; Qian N; O'Keefe D; Vosatka RJ; Walsh CP; Tycko B 《Human molecular genetics》1998,7(4):597-608
Human chromosome 11p15.5 and distal mouse chromosome 7 include a
megabase-scale chromosomal domain with multiple genes subject to parental
imprinting. Here we describe mouse and human versions of a novel imprinted
gene, IMPT1 , which lies between IPL and p57 KIP2 and which encodes a
predicted multi-membrane-spanning protein similar to bacterial and
eukaryotic polyspecific metabolite transporter and multi- drug resistance
pumps. Mouse Impt1 and human IMPT1 mRNAs are highly expressed in tissues
with metabolite transport functions, including liver, kidney, intestine,
extra-embryonic membranes and placenta, and there is strongly preferential
expression of the maternal allele in various mouse tissues at fetal stages.
In post-natal tissues there is persistent expression, but the allelic bias
attenuates. An allelic expression bias is also observed in human fetal and
post-natal tissues, but there is significant interindividual variation and
rare somatic allele switching. The fact that Impt1 is relatively repressed
on the paternal allele, together with data from other imprinted genes,
allows a statistical conclusion that the primary effect of human chromosome
11p15.5/mouse distal chromosome 7 imprinting is domain-wide relative
repression of genes on the paternal homolog. Dosage regulation of the
metabolite transporter gene(s) by imprinting might regulate placental and
fetal growth.
相似文献
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