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991.
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
992.
993.
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
994.
Paternal uniparental disomy of chromosome 6 and transient neonatal diabetes mellitus 总被引:3,自引:0,他引:3
Transient neonatal diabetes mellitus occurs in growth-retarded infants, has an incidence of 1 in 400000 live births and has been associated with both paternal uniparental disomy of chromosome 6 and paternal duplications of 6q. We analysed samples from our cohort of patients with transient neonatal diabetes mellitus for uniparental disomy of chromosome 6 using polymorphic microsatellite repeat analysis. We report here the fifth case of paternal uniparental disomy of chromosome 6 associated with classic transient neonatal diabetes mellitus and estimate that uniparental disomy of chromosome 6 accounts for approximately one fifth of cases of transient neonatal diabetes mellitus. 相似文献
995.
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
996.
AIM: The aim of this study was to identify factors associated with deaths by hanging among young people in Queensland, Australia. METHOD: An examination of coroner's reports for all deaths by hanging of people under 25 years of age that occurred in Queensland in the years 1995 and 1996. RESULTS: All cases were recorded as suicides. Most were males and a quarter were indigenous persons. Half the deaths occurred in regional or rural areas. Unemployment, the experience of personal loss, psychiatric illness and alcohol use were possible precipitating agents. Early warning signs were the onset of uncharacteristic behaviours and threats of suicide. CONCLUSIONS: The private nature of hanging means that there are rarely opportunities to prevent it in the period immediately before the fatal event. Earlier interventions will have to be considered. To prevent hanging as a means of suicide, we need to understand more about the difficulties experienced by some young men who are living in rural areas. We need more information about the cultural problems experienced by indigenous youths in their teenage years. Young people in the justice system may need personal support. There is a pressing need to determine if young people, especially in rural areas, have adequate access to the professional expertise needed to diagnose and treat mental disorders. 相似文献
997.
目的 应用双标稳定同位素1 3C 乳糖2 H 葡萄糖负荷试验对乳糖酶缺乏者小肠粘膜乳糖酶活性进行定量分析。方法 选用4 3名乳糖酶缺乏者(呼气ΔH2 浓度>2 0 μmol mol)作为实验对象,根据乳糖不耐受症状记录分为乳糖吸收不良组(LM)和乳糖不耐受组(LI)。以2 5g1 3C 乳糖和0 . 5g2 H 葡萄糖作为受试底物,分析受试者摄入底物之后各时点血浆中总葡萄糖、1 3C 葡萄糖和2 H 葡萄糖浓度,并计算各时点1 3C 葡萄糖2 H 葡萄糖吸收百分率的比值,以4 5min、6 0min、75min三个时点所得比值的均值作为乳糖消化指数(LDI)来反应小肠乳糖酶活性。结果 乳糖吸收不良组和乳糖不耐受组两组各时点血浆总葡萄糖、1 3C 葡萄糖无显著性差异,乳糖吸收不良组的乳糖消化指数显著高于乳糖不耐受组(0 . 4 7±0 .15vs 0 . 34±0 . 14 ) ;乳糖消化指数与6h累积H2 呼出量无显著性相关关系(r=0 . 12 ,P =0 .4 6 ) ;经H2 呼气试验结果判定为乳糖酶缺乏的个体,经1 3C 乳糖 2 H 葡萄糖负荷试验分析显示小肠粘膜仍存在一定乳糖酶活性。结论 采用双标稳定同位素1 3C 乳糖2 H 葡萄糖负荷试验可以准确、灵敏地定量分析小肠粘膜乳糖酶活性,同时可以计算体内乳糖消化量。 相似文献
998.
益生菌和酸奶对乳糖不耐受者的作用研究 总被引:7,自引:0,他引:7
目的:研究益生菌和酸奶对乳糖不耐症(lactoseintolerance,LI)者的作用及其机制。方法:以经乳糖负荷试验筛选的乳糖不耐受者11名为对象,持续摄入益生菌(含B.longum)和酸奶(含L.bulgaricus,S.thermophilus,B.animalis)14d进行补充研究。试验分3个阶段,第1阶段为基值阶段1w,第2阶段为补充阶段2w,第3阶段为补充后阶段1w。在第2阶段前后1d分别进行双标稳定同位素13C-lactose/2H-glucose负荷试验,分析受试者摄入底物后6h呼气H2浓度值,以及血浆13C-glucose和2H-glucose浓度,并计算乳糖消化指数(lactosedigestionindex,LDI),乳糖消化量和口—结肠转运时间(orocecaltransittime,OCTT)。整个实验期间共收集5次粪便样本,分析β-半乳糖苷酶活性。结果:在第2阶段补充结束后个体LI症状评分显著低于补充前(7.09±5.50vs16.09±10.03,P<0.05);LDI、乳糖消化量、OCTT和各时间点呼气H2浓度在补充前后无显著性改变;粪便β-半乳糖苷酶活性在补充第1w即开始升高,补充第2w显著高于基值(147.6±165.8IUvs77.3±77.2IU,P<0.05)。结论:持续摄入益生菌和酸奶具有明显改善乳糖不耐受症状的作用,其原因可能与结肠β-半乳糖苷酶活性的增加有关。 相似文献
999.
Two children had pain in one arm, followed by weakness and wasting, after an acute exacerbation of bronchial asthma. Similar cases in which a poliomyelitis-like illness was associated with acute asthma have been reported, but the relationship between the two remains conjectural. 相似文献
1000.
24-Hour urinary glucose excretion was measured in 43 juvenile diabetics during treatment as outpatients. In 20 children studied twice over 1-3 months there was good correlation between glucose excretion on each occasion. Subdivision of the collections into the periods 08 therefore 00-20 therefore 00 and 20 therefore 00-08 therefore 00 hours gave slightly less consistent results with correlation coefficients of 0 therefore 83 and 0 therefore 80, respectively, between the results of the repeat tests. In 37 prepubertal children, 24-hour glucose concentration and height velocity over the previous year were compared, and a highly significant negative correlation found. 10 of the 12 children with glucose excretion greater than 40 g/d had height velocities more than 1 SD below the mean for age, while only 2 of the 25 subjects excreting less than 40 g/d had height velocities more than 1 SD below the mean. The results indicate that estimation of 24-hour urine glucose excretion can be a useful index for monitoring treatment and that subdivision of the total collection may be of value in selecting the most suitable insulin regimen for the patient. 相似文献