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61.
T M Calero Moreno G Gustafsson S Garwicz D Grandér G K Jonmundsson B-M Frost A M?kipernaa O Rasool E-R Savolainen K Schmiegelow S S?derh?ll K Vettenranta F Wesenberg S Einhorn M Heyman 《Leukemia》2002,16(10):2037-2045
Inactivation of the Ink4 gene locus locus on 9p comprising the tumour suppressor gene p16ink4a and its neighbours p14ARF and p15ink4b is common in childhood acute lymphoblastic leukaemia (ALL), but the prognostic significance is controversial. DNA from 230 patients was retrospectively analysed by Southern blotting, single strand conformation polymorphism (SSCP) and sequencing techniques. The results were correlated with clinical characteristics and outcome. One hundred and ninety-four fully analysed patients, similarly treated using the Nordic NOPHO-86 or the current NOPHO-92 protocols, were included in the outcome analysis. Deletions approached a minimally deleted region between the p16ink4a and p15ink4b genes, making the p14ARF gene the most commonly deleted coding sequence. Bi-allelic deletion was associated with high white blood cell count (WBC) (P < 0.001), T cell phenotype (P < 0.001) and mediastinal mass (P < 0.001). Patients with Ink4 locus bi-allelic deletions had an inferior pEFS (P < 0.01) and multivariate analysis indicated that bi-allelic deletion of the p16ink4a and the p14ARF genes was an independent prognostic risk factor (P < 0.05). Sub-group analysis revealed a pronounced impact of deletion status for high-risk patients, ie with high WBC. Deletion-status and clinical risk criteria (WBC) could thus be combined to further differentiate risk within the high-risk group. The analysis of the Ink4 locus adds independent prognostic information in childhood ALL treated by Nordic protocols and may help in selection of patients for alternative treatment. 相似文献
62.
Positive effect of rebamipide on gastric permeability in mice after eradication of Helicobacter felis 总被引:4,自引:0,他引:4
Matysiak-Budnik T de Mascarel A Abely M Mayo K Heyman M Mégraud F 《Scandinavian journal of gastroenterology》2000,35(5):470-475
BACKGROUND: Despite Helicobacter pylori eradication, gastric inflammation persists for months or years. Preliminary results have indicated that an increase in gastric permeability could be one reason. Our aim was to evaluate the effect of a mucosal protective drug, rebamipide, on gastric permeability in a model of H. felis-infected mice. METHODS: Thirty-three C57/BL6 mice were inoculated with H. felis, and seven controls were kept non-inoculated. After 2 months 20 infected mice were treated with omeprazole, amoxicillin, and clarithromycin for 1 week and then for 4 weeks with either rebamipide (n = 9) or placebo (n = 11). The 13 remaining mice were kept untreated. After cessation of treatment, a fragment of antrum obtained from each mouse was mounted in a small Ussing chamber to study the electric resistance of the tissue (R) and antral permeability. RESULTS: No modification of the paracellular permeability (R, JNa, JMan) was observed in either group. However, the transcellular permeability to horseradish peroxidase (HRP) was significantly increased in H. felis-infected non-treated mice (1131 +/- 463, 948 +/- 339, and 182 +/- 312 ng/h x cm2) as compared with non-infected controls (469 +/- 262, 458 +/- 261, and 10 +/- 6 ng/ h x cm2, for J3H-HRP, JD, and JHRPi, respectively) (P < 0.003). Eradication of the bacteria by antibiotics without subsequent treatment with rebamipide led to a non-significant decrease in the HRP fluxes. However, when rebamipide was used after the antibiotic treatment, a significant (P < 0.01) decrease in HRP fluxes as compared with non-treated mice was observed. CONCLUSIONS: These results confirm that gastric permeability to macromolecules remains increased despite H. felis eradication and show that rebamipide can facilitate the normalization of gastric permeability to macromolecules after bacterial eradication. 相似文献
63.
Perkins SN; Hursting SD; Haines DC; James SJ; Miller BJ; Phang JM 《Carcinogenesis》1997,18(5):989-994
Transgenic mice with both alleles of the p53 tumor suppressor gene product
'knocked out' by gene targeting are susceptible to early development of
tumors, chiefly lymphomas and sarcomas. Compared with the control group,
administration of dehydroepiandrosterone (DHEA) at 0.3% of the diet to male
p53-deficient mice extended their lifespan by delaying death due to
neoplasms (from 105 to 166 days on study, P = 0.002), primarily by
suppressing lymphoblastic lymphoma (from 45 to 6% of neoplastic deaths, P =
0.010). Treatment with a synthetic DHEA analog,
16alpha-fluoro-5-androsten-17-one (compound 8354), at 0.15% of the diet
also increased lifespan, to 140 days for mice that developed tumors (P =
0.037). The effects of these steroids on lifespan and tumor development did
not appear to be strongly related to inhibition of food consumption and
weight gain, in that a group pair-fed with control diet to the reduced food
consumption of the DHEA-treated group developed and died of the same types
of neoplasms at the same rate as the controls fed ad libitum. The
chemopreventive effect of these steroids has been proposed to be due to
suppression of DNA synthesis by inhibition of glucose 6-phosphate
dehydrogenase, the rate-limiting enzyme of the pentose phosphate pathway.
Although DHEA and its analog are strong non- competitive inhibitors of this
enzyme in vitro, treatment with DHEA did not deplete cellular nucleotide
pools in the liver, as would have been predicted. The chemopreventive
effect of DHEA in this model may be due to steroid-induced thymic atrophy
and suppression of T cell lymphoma, permitting these mice to survive long
enough to develop tumors with longer latency.
相似文献
64.
Numerous studies documented low intakes of iron, zinc, calcium, and other micronutrients in young children. A recent report suggests that intakes are low in both home food and food provided at day care centers. Most of the young children in that study could not have obtained adequate intakes of key micronutrients without major dietary changes. Is it time to recommend routine multivitamin/mineral supplementation for all young children? 相似文献
65.
AM VOGEL D LENNON SN AMERATUNGA J HOLYOAKE 《Journal of paediatrics and child health》1996,32(6):484-490
Objective : To establish the prevalence of specific chronic conditions of childhood in the Auckland area and to quantify resource use by these children.
Methodology : Estimates were made from available registry data and published data sources of the population of children with selected chronic conditions resident in the Auckland Area Health Board area. Resource use data were extracted for admissions to Auckland public hospitals and from providers of community based technology services.
Results : The largest community prevalence groups are those with asthma, intellectual handicap, congenital heart disease and epilepsy. Children aged 0-14 with chronic conditions accounted for at least 14340 hospital days stay in Auckland in 1992 at an estimated minimum cost of $7.9 million. Over 200 children are dependent on technological aids at home.
Conclusions : There are sparse data on the numbers and needs of children with chronic conditions in the population. A non-categorical approach which crosses disease entities may be the best method of meeting common needs. 相似文献
Methodology : Estimates were made from available registry data and published data sources of the population of children with selected chronic conditions resident in the Auckland Area Health Board area. Resource use data were extracted for admissions to Auckland public hospitals and from providers of community based technology services.
Results : The largest community prevalence groups are those with asthma, intellectual handicap, congenital heart disease and epilepsy. Children aged 0-14 with chronic conditions accounted for at least 14340 hospital days stay in Auckland in 1992 at an estimated minimum cost of $7.9 million. Over 200 children are dependent on technological aids at home.
Conclusions : There are sparse data on the numbers and needs of children with chronic conditions in the population. A non-categorical approach which crosses disease entities may be the best method of meeting common needs. 相似文献
66.
67.
The Consortium to Establish a Registry for Alzheimer's Disease (CERAD). Part I. Clinical and neuropsychological assessment of Alzheimer's disease 总被引:31,自引:0,他引:31
J C Morris A Heyman R C Mohs J P Hughes G van Belle G Fillenbaum E D Mellits C Clark 《Neurology》1989,39(9):1159-1165
The Consortium to Establish a Registry for Alzheimer's Disease (CERAD) has developed brief, comprehensive, and reliable batteries of clinical and neuropsychological tests for assessment of patients with the clinical diagnosis of Alzheimer's disease (AD). We administered these batteries in a standardized manner to more than 350 subjects with a diagnosis of AD and 275 control subjects who were enrolled in a nationwide registry by a consortium of 16 university medical centers. The tests selected for this study measured the primary cognitive manifestations of AD across a range of severity of the disorder, and discriminated between normal subjects and those with mild and moderate dementia. The batteries also detected deterioration of language, memory, praxis, and general intellectual status in subjects returning for reassessment 1 year later. Interrater and test-retest reliabilities were substantial. Long-term observations of this cohort are in progress in an effort to validate the clinical and neuropsychological assessments and to confirm the diagnosis by postmortem examinations. Although information on validation is limited thus far, the CERAD batteries appear to fill a need for a standardized, easily administered, and reliable instrument for evaluating persons with AD in multicenter research studies as well as in clinical practice. 相似文献
68.
69.
R W Fleischman U Schaeppi I A Heyman R S Phelan H Rosenkrantz V Ilievski 《Toxicology and applied pharmacology》1974,27(2):259-270
The toxicity of chromomycin A3, a potent antitumor antibiotic derived from Streptomyces griseus, was assessed in mice, dogs and monkeys. In mice, the LD50 after 5 daily iv doses was 603 μg/kg. In dogs and monkeys, the single-dose iv minimal lethal dose was 200 and 330 μg/kg, respectively, while this value after 5 daily iv doses was 100 μg/kg for both species. The principal clinicopathologic findings in dogs and monkeys that became moribund or died included emesis, hemorrhagic diarrhea, fever, dehydration, and necrosis of intestinal and lymphoid tissues with occasional necrosis in other organs. Laboratory findings were consistent with clinical signs. Dogs and monkeys that survived treatment exhibited mild, reversible toxic alterations. 相似文献