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991.
Estimating the incidence of typhoid fever and other febrile illnesses in developing countries 总被引:4,自引:0,他引:4
Crump JA Youssef FG Luby SP Wasfy MO Rangel JM Taalat M Oun SA Mahoney FJ 《Emerging infectious diseases》2003,9(5):539-544
To measure the incidence of typhoid fever and other febrile illnesses in Bilbeis District, Egypt, we conducted a household survey to determine patterns of health seeking among persons with fever. Then we established surveillance for 4 months among a representative sample of health providers who saw febrile patients. Health providers collected epidemiologic information and blood (for culture and serologic testing) from eligible patients. After adjusting for the provider sampling scheme, test sensitivity, and seasonality, we estimated that the incidence of typhoid fever was 13/100,000 persons per year, and the incidence of brucellosis was 18/100,000 persons per year in the district. This surveillance tool could have wide applications for surveillance for febrile illness in developing countries. 相似文献
992.
Rationale. The psychomotor stimulant properties of drugs are argued to be a key feature of abuse liability. Several studies, primarily
using inbred strains of mice, have demonstrated genetic variation in the psychomotor stimulant properties of cocaine. As of
yet, however, no gene(s) has been identified which influences this phenotype.
Objectives. The purpose of the present study was to examine a number of inbred strains of mice, including several closely related substrains,
for cocaine-induced locomotor activation. Such substrain differences would suggest the possibility of a major gene effect.
These data will also help to further characterize the range of genetic variation in response to cocaine.
Methods. Mice from 11 inbred strains were initially injected with saline and activity monitored for 30 min; mice were then removed
from the activity monitor, injected with saline or one of six doses of cocaine, and activity was monitored for an additional
30 min.
Results. Compared to several other closely related C57BL substrains, we found the C57BL/10SnJ substrain to be significantly less activated
following cocaine administration. In contrast, the C57BR/cdJ and C57L/J substrains showed extremely high levels of cocaine-induced
locomotor activation.
Conclusions. The genetic similarity between C57BL/10SnJ and the other closely related C57BL substrains suggests the possibility that the
aberrant behavioral response to cocaine observed in B10SnJ mice may be due to a major gene effect. Similarly, the differences
found in the C57BR/cdJ and C57L/J substrains may also be influenced by a major gene. The strains examined in this study will
be useful tools for identification of relevant quantitative trait loci.
Electronic Publication 相似文献
993.
Cui ZH Ikeda K Kawakami K Gonda T Nabika T Masuda J 《Clinical and experimental pharmacology & physiology》2003,30(7):464-469
1. To understand the roles of a putative hypertension gene in the chromosome 1 quantitative trait locus (QTL) region, the response to restraint stress was studied in strains congenic for this QTL. 2. To establish congenic strains, the QTL region was introgressed from stroke-prone spontaneously hypertensive rats (SHRSP)/Izm to Wistar-Kyoto/Izm (WKY/Izm) rats by repeated backcrossing. Two congenic strains (WKYpch1.0 and WKYpch1.1) were established to cover the whole QTL region between D1Wox29 and D1Arb21 (approximately 40 cM) and a smaller region between D1Smu11 and D1Arb21 (approximately 10 cM), respectively. After telemetry probes were implanted, rats were exposed to restraint stress to investigate the blood pressure response. 3. Basal blood pressure measured by radiotelemetry differed significantly between WKY rats and WKYpch1.0 (103 +/- 10 and 116 +/- 4 mmHg, respectively; P = 0.002 by anova). When exposed to restraint stress, WKYpch1.0 showed a greater increase in blood pressre than did WKY rats. The exaggerated response in the WKYpch1.0 strain was abolished by chemical sympathectomy using guanethidine. The WKYpch1.1 rats did not differ significantly from WKY rats either in basal blood pressure or in the response to restraint stress. 4. In conclusion, a QTL for high blood pressure was successfully introgressed in the established congenic strain, WKYpch1.0. A gene (or genes) in the chromosome 1 QTL region modulates the cardiovascular responses to restraint stress in these congenic rats, probably through the sympathetic nervous system. 相似文献
994.
Cinek O Kolousková S Snajderová M Sumník Z Sedláková P Drevínek P Vavrinec J Ronningen KS 《Pediatric diabetes》2001,2(3):98-102
Abstract: To examine human leukocyte antigen (HLA) class II association of type 1 diabetes mellitus (DM) in Czech children, we performed a case–control study of 261 patients diagnosed before the age of 15 and 289 non-diabetic control children. Complete HLA-DQA1, DQB1 genotyping and DRB1*04 subtyping were carried out by polymerase chain reactions with sequence-specific primers. The effect of the DRB1*04 subtypes was studied in DRB1*04 alleles carried on DQB1*0302-DQA1*03 haplotypes. The risk was statistically evaluated by testing 2 × 2 tables, considering corrected p-values < 0.05 significant. The DQB1*0302 (odds ratio, OR = 9.0), DQB1*0201 (OR = 3.4) and DQA1*03 (OR = 7.5) alleles were significantly associated with diabetes risk, while the DQB1*0602 (OR = 0.02), DQB1*0301 (OR = 0.08), DQB1*0503 (OR = 0.13), DQB1*0603 (OR = 0.20), DQA1*01 (OR = 0.28) and DQA1*02 (OR = 0.26) alleles were significantly protective. Of the DQA1-DQB1 genotypes, we point out the extremely high risk of OR = 116 conferred by HLA-DQA1*05-DQB1*0201/DQA1*03-DQB1*0302. Among DRB1*04 subtypes, DRB1*0403 was significantly protective (OR = 0.05, CI 95% 0.01–0.45). Since none of the remaining DRB1*04 subtypes was associated with type 1 DM, our study may present another piece of evidence that the DRB1*0401 and DRB1*0404 alleles do not modify type 1 diabetes risk generally in European populations. 相似文献
995.
我国人群中缺血性和出血性脑卒中发病的相对比例 总被引:16,自引:1,他引:15
目的 探讨我国人群中出血性和缺血性脑卒中发病的相对比例。方法 1 991~ 2 0 0 0年按照世界卫生组织MONICA方案对我国 1 5组人群脑卒中事件进行监测。结果 1 996~ 2 0 0 0年 1 5组人群的CT检查率从 1 4 .8%~ 97.5 %不等 ,缺血性和出血性脑卒中的比例从 0 .37∶1~ 3 .82∶1不等 ,两者的相关系数为 0 .71 (P =0 .0 0 3)。在CT检查率达到 80 %以上的人群 ,缺血性与出血性脑卒中的比例无一例外 ,均 >1 .0。从 1 991~ 2 0 0 0年 ,1 0年间均有资料的 1 2组人群CT检查率从 41 .1 %增加到88 3 % ,缺血性与出血性脑卒中的比例则从 1 .2 5∶1增加到 1 .85∶1 ,两者的相关系数为 0 .77(P =0 0 1 )。经CT检查的病例中 ,无论任何一年缺血性与出血性脑卒中的比例均大于 1 .0。结论 我国人群中脑卒中发病是以缺血性脑卒中为主。CT检查率偏低是造成部分人群“出血性脑卒中发病为主”假象的主要因素。 相似文献
996.
An Ile93Met substitution in the UCH-L1 gene is not a disease-causing mutation for idiopathic Parkinson’s disease 总被引:1,自引:0,他引:1
Objective To ascertain whether a coding mutation(Ⅱe93Met) in ubiquitin carboxy-terminal hydrolase(UCH-L1) gene plays a role in idiopathic Parkinson‘s disease(IPD).Methods Polymerase chain reaction-restriction fragment length polymorphism assay(PCR-RFLP) was used to distingusih the wild-type(two DNA fagments of 34 and 126bp)from the variant allele(three fragments of 34,60 and 66bp)because the mutation created a new site for restriction engonuclease Bsm F1.DNA was isolated from various blood samples using a phenolchlorofom extraction. 相似文献
997.
Baca-Garcia E Vaquero C Diaz-Sastre C Ceverino A Saiz-Ruiz J Fernández-Piquera J de Leon J 《European archives of psychiatry and clinical neuroscience》2003,253(6):281-285
Abstract.
This one-year naturalistic study included all suicide
attempters in a catchment area. In the first published set of
analyses, an association between menses and suicide attempts was
replicated. According to the polymorphism of the serotonin
transporter promoter area, the subjects can be classified as S
individuals (s/s or s/l) or L individuals (l/l). In the second
published set of analyses, L females appeared protected from
suicide attempts since they were underrepresented among female
(and not male) attempters. This new, unpublished third set of
analyses tested for an interaction between the same polymorphism
and low hormonal activity (during menses and menopause). In
fertile female attempters, the proportion of L women in the
menses (41%, 7/17) was significantly higher than expected in the
population (15.5 %) and almost significantly higher than in S
female attempters (22%,19/87). L females were also
overrepresented in postmenopausal attempters. Despite sample
size limitations, this gene-hormone interaction needs to be
further investigated in female suicide attempters. 相似文献
998.
Laakso MP Hiltunen Y Könönen M Kivipelto M Koivisto A Hallikainen M Soininen H 《Journal of neural transmission (Vienna, Austria : 1996)》2003,110(3):267-275
Summary. Apolipoprotein E (ApoE) genotype has been shown to influence results in neuroimaging studies using a number of various imaging
modalities. No in vivo data exists on whether or not there are ApoE-related changes observable by proton magnetic resonance
spectroscopy (MRS). In this study we measured absolute peak areas of proton MR spectra obtained from the occipital cortex
in 22 non-demented elderly with (n = 8) or without (n = 14) the ApoE ε4 allele. No statistically significant differences were
found in levels of N-acetyl aspartate, myo-inositol, or choline containing compounds between the groups. Instead, compared
with the non-carriers, the levels of creatine were significantly lower in the ε4 carriers, suggesting increased metabolic
demands in the brain of the ε4 carriers. The levels of creatine also correlated significantly with age and performance on
the Mini-Mental State Examination test in the ε4 carriers, but not in the non-carriers. These findings may be of significant
clinical interest as potential indicator of incipient AD, and also from therapeutical point of view given the potential neuroprotective
effects of creatine.
Received February 18, 2002; accepted August 5, 2002 Published online December 9, 2002
Acknowledgements This study was supported by the Research Council for Health of the Academy of Finland, the Finnish Neurology Foundation,
the Instrumentarium Research Foundation, and the Farmos Research Foundation.
Authors' address: M. Laakso, Department of Neurology, Bldg. 5, Kuopio University Hospital, P.O.Box 1777, 70211 Kuopio, Finland,
e-mail: mikko.laakso@uku.fi
Abbreviations AD Alzheimer's disease, ApoE apolipoprotein E, MI myo-inositol, MMSE Mini-Mental State Examination, MRI magnetic resonance imaging, MRS magnetic resonance spectroscopy, NAA N-acetyl aspartate. 相似文献
999.
Zeng YT 《中国医学科学院学报》2003,25(2):115-116
系统回顾了医学遗传学的发展历程,从形式遗传学、细胞遗传学、生化遗传学直到近代的分子遗传学;对分析与综合这一贯穿医学遗传学发展史的研究思路进行评述,并对今后医学遗传学的发展前景作一思考。 相似文献
1000.
Happé F Briskman J Frith U 《Journal of child psychology and psychiatry, and allied disciplines》2001,42(3):299-307
Previous twin and family studies have indicated that there are strong genetic influences in the etiology of autism, and provide support for the notion of a broader phenotype in first-degree relatives. The present study explored this phenotype in terms of one current cognitive theory of autism. Parents and brothers of boys with autism, boys with dyslexia, and normal boys were given tests of "central coherence", on which children with autism perform unusually well due to an information-processing bias favouring part/detail processing over processing of wholes/meaning. Results indicated that fathers of boys with autism, as a group, showed piecemeal processing across four tests of central coherence. This was not true for any other group. These findings raise the possibility that the broader autism phenotype may include a "cognitive style" (weak central coherence) that can confer information-processing advantages. 相似文献