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991.
992.
A syndrome of subacute respiratory distress, severe metabolic bone disease affecting the thoracic cage, and mild cholestasis occurred in 4 small preterm infants during the first three months of life and was associated with considerable morbidity. The early radiological features in the chest resembled thos of the Mikity-Wilson syndrome, with which the disorder may be confused. After spontaneous improvement in hepatic function 3 of the infants fully recovered. The fourth died of paralytic ileus. Various nutritional and absorptive abnormalities probably contribute to the pathogenesis of the bone disorder in this syndrome. The best prophylaxis might be to supplement the diet with 25-hydroxyvitamin D rather than native vitamin D. 相似文献
993.
TM Barratt JS Cameron C Chantler R Counahan CS Ogg JF Soothill 《Archives of disease in childhood》1977,52(6):462-463
A controlled trial of azathioprine treatment of steroid-responsive frequent-relapsing nephrotic syndrome of childhood failed to show a therapeutic effect on the stability of remission after withdrawal of corticosteroid treatment. 相似文献
994.
995.
996.
Recessive amyotrophic lateral sclerosis families with the D90A SOD1 mutation share a common founder: evidence for a linked protective factor 总被引:3,自引:0,他引:3
Al-Chalabi A; Andersen PM; Chioza B; Shaw C; Sham PC; Robberecht W; Matthijs G; Camu W; Marklund SL; Forsgren L; Rouleau G; Laing NG; Hurse PV; Siddique T; Leigh PN; Powell JF 《Human molecular genetics》1998,7(13):2045-2050
Amyotrophic lateral sclerosis (ALS) is a progressive motor
neurodegeneration resulting in paralysis and death from respiratory failure
within 3-5 years. About 20% of familial cases are associated with mutations
in the gene for copper/zinc superoxide dismutase ( SOD1 ), which catalyses
the dismutation of the superoxide radical to hydrogen peroxide and oxygen.
Experimental evidence suggests mutations act by a toxic gain of function
but the mechanism is unknown. There are >60 known SOD1 mutations
associated with ALS and all are dominant except for one in exon 4, a D90A
substitution which is recessive. D90A pedigrees with dominant inheritance
have now been reported and this apparent contradiction needs to be
explained. We performed a worldwide haplotype study on 28 D90A pedigrees
using six highly polymorphic microsatellite markers. We now show that all
20 recessive families share the same founder (alpha = 0.999), regardless of
geographical location, whereas several founders exist for the eight
dominant families (alpha = 0.385). This finding confirms that D90A can act
in a dominant fashion in keeping with all other SOD1 mutations, but that on
one occasion, a new instance of this mutation has been recessive. We
propose a tightly linked protective factor which modifies the toxic effect
of mutant SOD1 in recessive families.
相似文献
997.
M Cantin P Brochu C Turgeon-Knaack G Berdnikoff P Simard C Morin 《Archives of pathology & laboratory medicine》1976,100(8):422-426
Rectal biopsy material from a patient with type 4 glycogenosis was studied by ultrastructural cytochemical methods. The diagnosis of the disease was made on the basis of the patient's clinical history, the autopsy findings, and the histopathological features. Numerous large macrophages were observed in the rectal mucosa. They contained large vacuoles filled with filamentous material and small granules. This amylopectin was stained by the Thiery method (periodic acid-thiocarbohydrazide-silver proteinate) after 18 hours of exposure to thiocarbohydrazide; only 30 minutes was sufficient to demonstrate seemingly normal beta-glycogen particles in epithelial cells. 相似文献
998.
Reduced collagen VI causes Bethlem myopathy: a heterozygous COL6A1 nonsense mutation results in mRNA decay and functional haploinsufficiency 总被引:3,自引:1,他引:3
Lamande SR; Bateman JF; Hutchison W; McKinlay Gardner RJ; Bower SP; Byrne E; Dahl HH 《Human molecular genetics》1998,7(6):981-989
We have identified a new pathogenic mechanism for an inherited muscular
dystrophy in which functional haploinsufficiency of the extracellular
matrix protein collagen VI causes Bethlem myopathy. The heterozygous COL6A1
mutation results in a single base deletion from the mRNA and a premature
stop codon. The mutant mRNA is unstable, subject to nonsense- mediated mRNA
decay, and is almost completely absent both from patient fibroblasts and
skeletal muscle, resulting in haploinsufficiency of the alpha1(VI) subunit
and reduced production of structurally normal collagen VI. This is the
first example of a muscular dystrophy caused by haploinsufficiency of a
structural protein or member of the dystrophin-glycoprotein complex, and
identifies collagen VI as a critical contributor to cell-matrix adhesion in
skeletal muscle.
相似文献
999.
1000.
Feoli-Fonseca JC Oligny LL Brochu P Simard P Falconi S Yotov WV 《Journal of medical virology》2001,63(4):284-292
Human papillomaviruses (HPV) are etiological agents of cervical cancer. In order to address clinical demand for HPV detection and sequence typing, mostly in pre-cancerous cervical lesions, we applied our two-tier PCR-direct sequencing (PCR-DS) approach based on the use of both MY09/MY11 and GP5 + /GP6 + sets of primers. We tested 691 pathological specimens, all of which were biopsies, 75% of which were diagnosed histologically as cervical intraepithelial neoplasia (CIN) grades I-III. In total, 484 samples (70%) tested HPV-positive, yielding 531 HPV sequences from 47 HPV types, including two novel types. Four most frequently found HPV types accounted for 52.9% of all isolates: HPV6, 16, 11, and 31 (21.5%, 20.0%, 7.0%, and 4.5%, respectively). Some interesting results are the following: all currently known high-risk HPV (14 types) and low-risk HPV (6 types) were detected; HPV18 was not the 1st or 2nd but rather the 4th-5th most frequent high-risk HPV type; the highest detection rate for HPV (86%) among samples suspected to be HPV-infected was found in the youngest age group (0-10 years old), including 70% (44/63) "genital" HPV types; HPV types of undetermined cervical cancer risk represented 19% and of the total HPV isolates but were strongly increased in co-infections (36.5% of all isolates). To our knowledge, this is the largest sequencing-based study of HPV. The HPV types of unknown cancer risk, representing the majority of the known HPV types, 27 of the 47 types detected in this study, are not likely to play a major role in cervical cancer because their prevalence in CIN-I, II, and III declines from 16% to 8% to 2.5%. The two-tier PCR-DS method provides greater sensitivity than cycle sequencing using only one pair of primers. It could be used in a simple laboratory setting for quick and reliable typing of known and novel HPV from clinical specimens with fine sequence precision. It could also be applied to anti-cancer vaccine development. 相似文献