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991.
992.
Mueller PR; Ferrucci JT Jr; Simeone JF; Butch RJ; Wittenberg J; White M; Brown AS 《Radiology》1985,155(3):615-618
Twelve abscesses and fluid collections in the lesser peritoneal sac were drained percutaneously using an access route across the intervening liver. This rather unusual access was chosen when other approaches were contraindicated because of surrounding colon, stomach, or spleen. All collections were drained successfully, and no specific complications such as hemorrhage, bile leak, or liver abscess occurred. Placement of an abscess drainage catheter should be done through the peripheral portion of the liver if possible. The technique offers a new, safe approach to percutaneous drainage of hitherto inaccessible collections. 相似文献
993.
RJ Ruben IF Wallace J Gravel 《Indian journal of otolaryngology and head and neck surgery》1997,49(2):94-96
A cohort of lower socio-economic children who experienced multiple and prolonged episodes of otitis media (OM) during their first year of life were compared to an equivalent group of children who were largely free of OM during their first year. Both groups were followed until 9 years of age. The data indicate that children with positive histories of OM performed poorer on a variety of Iinguisitc tasks across the nine year age span than the children with the positive histories of OM. The results suggest that the effect of the otitis media and its accompanying hearing loss on communication skills may extend throughout childhood. 相似文献
994.
995.
Dumaz N; van Kranen HJ; de Vries A; Berg RJ; Wester PW; van Kreijl CF; Sarasin A; Daya-Grosjean L; de Gruijl FR 《Carcinogenesis》1997,18(5):897-904
Mutation spectra of the p53 gene from human skin carcinomas have been
connected to solar UV radiation. For comparison we have characterized the
mutation spectrum of the p53 gene in a very large sample of squamous cell
carcinomas from hairless mice induced with UV of wavelength 280-320 nm
(UV-B), which have substantiated the mutagenic effects of UV-B radiation in
vivo. Tumors from hairless mice, random bred SKH:HR1 as well as inbred
SKH:HRA strains, which are analyzed for mutations in the conserved domains
of the p53 protein present a very specific mutation spectrum. The observed
mutation frequency after chronic UV-B radiation in the p53 gene ranged from
54% (SKH-HRA) to 73% (SKH-HR1) among the 160 tumors analyzed. Over 95% of
the mutations were found at dipyrimidine sites located in the
non-transcribed strand, the majority were C-->T transitions and 5% were
CC-->TT tandem double mutations. Four distinct UV-B mutation hot spots
have been identified for the first time: two major ones at codons 267 (33%)
and 272 (19%) and two minor ones at codons 146 (10%) and 173 (4%). The
codon 267 hot spot consists of a CpG preceded by a pyrimidine, which
confirms in vivo an important role for this UV-B mutable site in
UV-B-induced skin tumors that is not found in other types of mouse tumors.
Comparison with mutation spectra from human skin carcinomas fully validates
the merits of the hairless mouse model for studying the molecular
mechanisms of skin carcinogenesis. For example, the murine hot spot at
codon 272 does have a full equivalent in human skin carcinomas. In
contrast, the human equivalent of the murine codon 267 lacks the
dipyrimidine site and therefore fails to be a pronounced hot spot in human
skin carcinomas; however, this site is one of the major hot spots in human
internal cancers (evidently not induced by UV radiation but probably by
deamination of the 5 methyl cytosine).
相似文献
996.
LANGUAGE="EN">Summary. In this paper the organisation of a radiology satellite department is described. In the satellite department only bucky examinations are performed, thus avoiding the need for the duplication of sophisticated material and specialized staff. The satellite department maintains as efficient a service as the main radiology department. For this purpose a digital radiology system was chosen for the satellite department. This system permits digital data to be sent to the main location. This results in a maximisation of the advantages of a two-location system as well as avoiding the need for patients' files to be moved between different locations. 相似文献
997.
Iatrogenic DNA damage induced in human spermatozoa during sperm preparation: protective significance of seminal plasma 总被引:9,自引:1,他引:9
Twigg J; Irvine DS; Houston P; Fulton N; Michael L; Aitken RJ 《Molecular human reproduction》1998,4(5):439-445
Before the advent of intracytoplasmic sperm injection (ICSI) semen
preparation techniques focused on the need to sustain the fertilizing
potential of the spermatozoa particularly by reducing oxidative stress.
However, for severely oligozoospermic patients treated by ICSI, sperm
preparation protocols are used which aim to maximize sperm recovery rather
than sperm function. In this study we have examined the impact of different
sperm preparation techniques on oxidative stress, sperm motion and DNA
integrity. Reactive oxygen species (ROS) generation was monitored using
luminol-dependent chemiluminescence, seminal antioxidant activity was
assessed using a total reactive antioxidant potential (TRAP) assay while
sperm motility and DNA damage were evaluated using computer assisted semen
analysis and in-situ nick translation respectively. The results demonstrate
a significant increase in the levels of ROS generated by samples prepared
by swim-up from a washed pellet compared with spermatozoa isolated directly
from seminal plasma. This oxidative stress was associated with a highly
significant increase in the level of DNA damage sustained by the
spermatozoa while the quality of sperm motility remained largely unchanged.
These results suggest that if repeated centifugation protocols are to be
used to prepare spermatozoa, strategies should be developed for minimizing
collateral DNA damage.
相似文献
998.
Nuclear genes of human complex I of the mitochondrial electron transport chain: state of the art 总被引:4,自引:3,他引:4
Smeitink JA; Loeffen JL; Triepels RH; Smeets RJ; Trijbels JM; van den Heuvel LP 《Human molecular genetics》1998,7(10):1573-1579
The mitochondrial electron transport chain (mtETC) consists of four
multi-subunit enzyme complexes. Complex I or NADH:ubiquinone
oxidoreductase, the largest mtETC multisubunit complex, consists of
approximately 41 subunits. Seven of these subunits are encoded by the
mitochondrial genome, the remainder by the nuclear genome. Among the
mitochondriocytopathies, complex I deficiencies are encountered frequently.
Although some complex I deficiencies have been associated with
mitochondrial DNA mutations, the genetic defect has not been elucidated in
the majority of complex I-deficient patients. It is expected that many of
these patients have mutations in the nuclear- encoded subunits of this
complex, so vital for cellular energy production. After a brief summary of
the current knowledge of complex I from cow, bacteria and fungi, this
review presents the state of the art of the knowledge of the human
nuclear-encoded complex I genes which, in the last 18 months, has made
enormous progress. At present, the complete gene structure of four subunits
and the cDNA structure of 18 of the 34 complex I nuclear-encoded subunits
are known. Mapping of these subunits shows a random distribution over the
chromosomes. The chromosomal localization is known for 14 complex I genes.
Recently, the first mutation, a 5 bp duplication in the 18 kDa (AQDQ)
subunit, has been reported. We expect that within 1 year all human
nuclear-encoded complex I subunits will be cloned. Mutational analysis of
these subunits is warranted in complex I-deficient patients and will not
only be important for genetic counselling but will also extend the
knowledge regarding the functional properties of the individual human
complex I subunits.
相似文献
999.
1000.