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1.
Objective: Considering the growing use of cellular phones and the fast appearance of new phone models, the electromagnetic interference of currently popular cellular phones on electronic medical equipment was tested. Methods: Three Personal Communication System cellular phones were put at different distances from multiple electronic medical devices, the interference effect was observed and the electromagnetic field strength measured with a spectrum analyser. Results: Only two small pieces of equipment, the CO2 airway adapter and the haemoglucostix meter were affected and then only when the phone was in very close proximity. Conclusion: Compared to the results of our study in 1997 testing Global System for Mobile Communication phones, the Personal Communication System phones generated less electromagnetic interference. However a much larger scaled study and an accurate international electromagnetic interference standard are recommended before any change in the current restrictive hospital policy on mobile phone usage could be recommended. 相似文献
2.
Selecting an appropriate working correlation structure is pertinent to clustered data analysis using generalized estimating equations (GEE) because an inappropriate choice will lead to inefficient parameter estimation. We investigate the well‐known criterion of QIC for selecting a working correlation structure, and have found that performance of the QIC is deteriorated by a term that is theoretically independent of the correlation structures but has to be estimated with an error. This leads us to propose a correlation information criterion (CIC) that substantially improves the QIC performance. Extensive simulation studies indicate that the CIC has remarkable improvement in selecting the correct correlation structures. We also illustrate our findings using a data set from the Madras Longitudinal Schizophrenia Study. Copyright © 2008 John Wiley & Sons, Ltd. 相似文献
3.
LY Chow MRCPsych D Chung MRCPsych V Leung MB BS TF Leung MB ChB CM Leung MRCPsych 《International journal of clinical practice》1997,51(5):330-331
Akathisia as a side-effect of metoclopramide has received increasing attention in consultation-liaison psychiatry in recent years. A case of metoclopramide-induced akathisia resulting in a suicide attempt is reported in order to highlight the suffering of such patients and the factors that lead to misdiagnosis. 相似文献
4.
John Hill Robert C. Stuart Hin K. Fung Enders K.W. Ng Fanny M. Cheung Sidney C.S. Chung C. Andrew van Hasselt 《The Laryngoscope》1997,107(10):1373-1377
The aim of this study was to investigate the origin of globus pharyngis with particular reference to esophageal disorders such as gastroesophageal reflux disease (GERD), motility disorders, structural abnormalities, other gastrointestinal tract diseases, and psychological profile. Previous studies on this subject using 24-hour pH monitoring give conflicting results and are hampered by the high background prevalence of asymptomatic GERD in the normal Western population. The local Chinese population is known to have a very low background level of GERD and therefore is an ideal study population. Twenty-six patients with globus pharyngis underwent 24-hour ambulatory pH monitoring, esophageal manometry, and esophagogas-troduodenoscopy with lower esophageal biopsy. A control group of 20 patients presenting with non-ulcer dyspepsia was similarly investigated. Personality profiles of the globus pharyngis subjects and an appropriate control group were assessed. Eight of the globus pharyngis group (30.7%) had evidence of GERD, whereas only one of the controls (5%) demonstrated GERD on 24-hour esophageal pH monitoring (P < 0.05). The manometric and personality profile studies did not show significant differences between study and control groups. We concluded that the finding of GERD in patients with globus pharyngis is not a coincidental finding but that there is a true association between GERD and globus pharyngis. 相似文献
5.
G. M. Brieger M. Mongelli L. Y. Hin T. K. H. Chung 《International urogynecology journal》1997,8(4):191-195
The epidemiology of urinary dysfunction in a Chinese population living in Hong Kong was investigated. Fifteen hundred ethnic
Chinese women answered a telephone questionnaire including symptoms of urinary dysfunction, anthropometric measurements, obstetric
history and place of birth. The relative predictive value of these factors was analyzed using logistic regression. The prevalence
of urinary dysfunction was 13%. Ten percent reported stress incontinence, and 4% had urgency or urge incontinence. The strongest
predictor was place of birth, with women born in mainland China having the highest prevalence of pure stress incontinence
(OR 1.33, CI 1.1–1.6). For the symptoms of detrusor instability age was the strongest predictor, with women over 50 years
being at greater risk (OR 2.8, CI 1.6–5.0). Contrary to earlier beliefs, urinary dysfunction in Chinese women is as common
as in Caucasian women. Place of birth is the strongest predictor for pure stress incontinence, with women born in mainland
China being at greater risk. This suggests that environmental factors in early life have a differential effect on the development
of urinary incontinence.
EDITORIAL COMMENT: Taiwan Chinese women have a comparable prevalence of urinary dysfunction with Hong Kong Chinese women.
A survey representing a multistage sample of 82 678 women aged 18 years or older was conducted in the Taipei area from January
to June 1993. A total of 818 cases were interviewed by trained students. One hundred and eighty-nine (23.1%) of the respondents
reported having had some degree of incontinence in the preceding 12 months, 28 (3.4%) reporting regular incontinence. Most
presented with stress urinary incontinence, whereas urge incontinence and mixed incontinence were more commonly seen in the
elderly group (aged 60 years or older). The risk factors for urinary incontinence included age, number of vaginal deliveries
(>3), number of abortions (>2) and maternal history of incontinence. Voiding symptoms (irritative or obstructive) and constipation
were significantly more prevalent among respondents with incontinence than those without (P<0.001). This evidence also indicates that the long-held belief that Chinese women have a much lower prevalence of urinary
dysfunction than western women has all but ended. 相似文献
6.
BACKGROUND:Wilson disease (WD)damages liver,brain,kidney,cornea and nervous system severely.It is manifested in four ways:brain,liver,kidney and bone muscle.Whether or not magnetic resonance imagling (MRI)can clearly display the diseased region and range in brain of patient with WD,which provides imageological evidence for clinical practice,is unclear.OBJECTIVE:To observe the charactedstics of MRI of brain in patient with SD,and analyze the correlation of diseased region with clinical symptoms.DESIGN:Retrospective case-analysis.SETTING:Department of Radiology,Second Hospital Affiliated to the General Hospital of Chinese PLA.PARTICIPANTS:Thirty-one patients,including 18 males and 13 females,with WD admitted to the Department of Neurology,Second Hospital Affiliated to the General Hospital of Chinese PLA between January 1999and December 2005 were retrieved.The involved patients presented serum copper oxidase (sCP) activity decreasling and/or caruloplasmin Ievel decreasling and/or urinary copper content increasling;typical extrapyramidal symptoms and/or physical sign;abnormality showed by slit-lamp examination,Kayser-Fleischer rling positive.METHODS:①All the involved patients underwent MRI examination.A GE 1.5T imagling equipment was used.Spin-echo sequence was adopted to perform T2 and T1-weighed image at transverse axis level.Partial cases subjected to head scannling at coronal and/or sagittal level.Gd-DTPA With dosage of 0.1 mmol/kg was the strongest in 4 cases.②MRI characteristics of patients with dliferent clinical symptoms were observed.MAIN OUTCOME MEASURES:MRI detection results of patients with WD and MRI characteristics of patients with different clinical symptoms.RESULTS:Thirty-one patients with WD participated in the result analysis.①Imageological examination results:WD lnvolved many regions in the brain:dorsal caudate putamen(n=28),thalamencephalon(n=25),mesencaphalon(n=25),globus pallidus(n=23),pons(n=21),posterlor limb of intemal capsule(n=16),dentate nucleus(n=16),caudata nucleus(n=15)and cerebral cortex(n=11).MRI presented hypo-intensity signal on T2-weighted image and T1-weighted image or isointensity signal on T1-weighted image in 24 patients,characteristic hypo-intensity signal of globus pallidus in 4 patients,mixed signal of hyper-and hypo-intensity in 2 patients,hypo-intensity signal of globus pallidus,pars anterior pedunculi carebd and pontine tegmentum on T1-weighted image in 1 patient.Pathological changes distdbuted in symmetry and focus of infection mostly presented mottling,lamellar or strip.Different degrses of cerebral cortex atrophy,especially subtentodal cerebellar atrophy,ware found in 20 patients.Four patients subjected to enhancement scannling,but no clear imaqling was found.③MRI characteristics of patients with different symptoms:Abnormal signal of dorsal caudate putamen was found in 28 patients with dystonia,21 patients with dysarthda and 16 patients with bradykinesia;Abnormal signal of mesencaphalon was found in 22 patients with trepidation,among which,18 presented abnormal signal of pons;Abnormal signal of caudate nucleus and lenticular nucleus was found in 15 patients with dysphagia;Abnormal signal of dentate nucleus was found in 16 patients with carebellar ataxia;Different degrees of changes in cerebral atrophy were found in 14 patients with detedoratling memory and dementia.CONCLUSION:MRI can clearly display the characteristics of diseased regions in brain of patient with WD.Diseased regions reflected by MRI have obvious differences in patients with different clinical neurosigns. 相似文献
7.
以18-甲基-17β-羟基-17α-乙炔基-雌甾-4-烯-3-酮(18-甲基炔诺酮),17β-羟基-17α-乙缺基-雌甾-4-烯-3-酮(炔诺酮),17β-羟基-17α-乙炔基-雄甾-4-烯-3-酮(妊娠素)和17a-羟基孕甾-4-烯-3,20二酮(17α-羟基黄体酮)为原料,经NaBH,还原、脱水、双键转位和酯化等反应合成一系列3,5-甾二烯化合物,用1HNMR和MS证明了它们的结构。动物筛选结果表明,17β-丙酰氧基-17α-乙炔基-雌甾-3,5-二烯(IVb2有明显的抗早孕活性。中断早期妊娠的作用似与其雌激素活性有关。 相似文献
8.
9.
10.
The relationship between dietary fat intake and risk of colorectal cancer: evidence from the combined analysis of 13 case-control studies 总被引:3,自引:0,他引:3
Geoffrey R. Howe Kristan J. Aronson Enrique Benito Roberto Castelleto Jacqueline Cornée Stephen Duffy Richard P. Gallagher José M. Iscovich Jiao Deng-ao Rudolf Kaaks Gabriel A. Kune Susan Kune Hin P. Lee Marion Lee Anthony B. Miller Ruth K. Peters John D. Potter Elio Riboli Martha L. Slattery Dimitrios Trichopoulos Albert Tuyns Anastasia Tzonou Lyndsey F. Watson Alice S. Whittemore Anna H. Wu-Williams Zheng Shu 《Cancer causes & control : CCC》1997,8(2):215-228
The objective of this study was to examine the effects of the intakeof dietary fat upon colorectal cancer risk in a combined analysis of datafrom 13 case-control studies previously conducted in populations withdiffering colorectal cancer rates and dietary practices. Original datarecords for 5,287 cases of colorectal cancer and 10,470 controls werecombined. Logistic regression analysis was used to estimate odds ratios (OR)for intakes of total energy, total fat and its components, and cholesterol.Positive associations with energy intake were observed for 11 of the 13studies. However, there was little, if any, evidence of anyenergy-independent effect of either total fat with ORs of 1.00, 0.95, 1.01,1.02, and 0.92 for quintiles of residuals of total fat intake (P trend =0.67) or for saturated fat with ORs of 1.00, 1.08, 1.06, 1.21, and 1.06 (Ptrend = 0.39). The analysis suggests that, among these case-control studies,there is no energy-independent association between dietary fat intake andrisk of colorectal cancer. It also suggests that simple substitution of fatby other sources of calories is unlikely to reduce meaningfully the risk ofcolorectal cancer. 相似文献