全文获取类型
收费全文 | 1265篇 |
免费 | 186篇 |
国内免费 | 18篇 |
专业分类
耳鼻咽喉 | 18篇 |
儿科学 | 65篇 |
妇产科学 | 13篇 |
基础医学 | 87篇 |
口腔科学 | 15篇 |
临床医学 | 186篇 |
内科学 | 299篇 |
皮肤病学 | 33篇 |
神经病学 | 61篇 |
特种医学 | 86篇 |
外科学 | 294篇 |
综合类 | 52篇 |
现状与发展 | 20篇 |
预防医学 | 64篇 |
眼科学 | 44篇 |
药学 | 63篇 |
中国医学 | 2篇 |
肿瘤学 | 67篇 |
出版年
2024年 | 7篇 |
2023年 | 43篇 |
2022年 | 6篇 |
2021年 | 19篇 |
2020年 | 25篇 |
2019年 | 15篇 |
2018年 | 60篇 |
2017年 | 50篇 |
2016年 | 38篇 |
2015年 | 47篇 |
2014年 | 45篇 |
2013年 | 69篇 |
2012年 | 47篇 |
2011年 | 49篇 |
2010年 | 57篇 |
2009年 | 75篇 |
2008年 | 40篇 |
2007年 | 34篇 |
2006年 | 37篇 |
2005年 | 25篇 |
2004年 | 23篇 |
2003年 | 28篇 |
2002年 | 28篇 |
2001年 | 29篇 |
2000年 | 28篇 |
1999年 | 33篇 |
1998年 | 32篇 |
1997年 | 39篇 |
1996年 | 50篇 |
1995年 | 31篇 |
1994年 | 22篇 |
1993年 | 25篇 |
1992年 | 23篇 |
1991年 | 17篇 |
1990年 | 17篇 |
1989年 | 31篇 |
1988年 | 28篇 |
1987年 | 24篇 |
1986年 | 30篇 |
1985年 | 20篇 |
1984年 | 9篇 |
1983年 | 9篇 |
1982年 | 12篇 |
1981年 | 11篇 |
1980年 | 6篇 |
1979年 | 9篇 |
1978年 | 13篇 |
1977年 | 9篇 |
1976年 | 7篇 |
1964年 | 5篇 |
排序方式: 共有1469条查询结果,搜索用时 15 毫秒
61.
基于光电传感器的多段脉搏波传播速度检测系统的研制 总被引:2,自引:4,他引:2
采用了一种以反射式和透射式红外光光电传感器和单片机为基础,用同步检测心电信号、桡动脉脉搏波、手指脉搏波信号来测定桡动脉和外周动脉脉搏波传播速度的方法,研制一种无创的多段脉搏波传播速度检测系统。在软件编程中脉搏波周期信号的识别是以心电R波峰值为基准,同时再根据它们之间的时延关系进一步确定脉搏波的波峰与波谷的范围,提高检测准确性及精度。该系统通过检测心电、桡动脉脉搏波和手指脉搏波信号可获得多段脉搏波传播速度参数,具有较高的检测精度和良好的应用前景。 相似文献
62.
BM Winklhofer-Roob MA van't Hof DH Shmerling 《Acta paediatrica (Oslo, Norway : 1992)》1995,84(10):1132-1136
The aim of this study was to determine the efficacy of long-term oral β -carotene supplementation for correcting impaired β -carotene status in cystic fibrosis patients. Thirty-five patients (2.3-30.5 years of age) with coefficients of fat absorption of 46-96% (median 88%) received β -carotene 0.5 mg/kg daily and were followed over a 16-month treatment period. Baseline plasma β -carotene concentrations in patients (meanSD, 0.090.06 μ mol/1) were significantly lower than those of age-matched controls (0.860.56 μ mol/1) ( p < 0.0001). Concentrations increased rapidly and reached a plateau at or before 3 weeks that was maintained throughout the study period. Values obtained at 3 weeks (0.890.64 μ mol/1) were significantly higher ( p < 0.0001) than those at baseline and did not differ from controls. Plasma retinol and α -tocopherol concentrations increased during the observation period, but remained within normal ranges. Plasma retinyl palmitate, which was below the detection limit in all but one patient at baseline, did not increase. Thus oral β -carotene supplementation is effective and normalizes β -carotene status of cystic fibrosis patients without evidence of significant side effects. β -Carotene, cystic fibrosis, LDL-cholesterol, oral supplementation, retinol, α-tocopherol 相似文献
63.
MA Hurrell C McLean P Desmond BM Tress A Kaye 《Journal of Medical Imaging and Radiation Oncology》1995,39(1):86-89
A case of malignant granular cell tumour of the sciatic nerve is presented. Computed tomography demonstrated iso-density with muscle and minimal enhancement. Magnetic resonance demonstrated T1 isointensity with muscle with marked enhancement, and isointensity with fat on proton and T2 images. Pathological evidence is presented for its probable Schwann cell histogenesis. 相似文献
64.
BRITT-LOUISE SUNESON RN CHRISTER LINDHOLM MD DMSc ELISABETH HAMRIN RN BM DMSc 《European journal of cancer care》1996,5(1):7-12
The clinical incidence of lymphoedema of the arm in breast cancer patients was studied before and after general mammography screening in the country of jönköping, Sweden. There was a significant decrease of incidence of lymphoedema from 15% in 1983 to 8% in 1988. Clinical and pathological therapy data have been analysed in relation to lymphoedema. Significant factors contributing to lymphoedema were the number of lymph nodes examined and the number of pathologically positive lymph nodes. A higher proportion of patients receiving post-operative radiotherapy to the axilla developed lymphoedema, compared with those with surgery alone.
A comparison between the two groups is impossible due to the fact that post-operative radiotherapy was prescribed only to patients with pathologically positive lymph nodes. 相似文献
A comparison between the two groups is impossible due to the fact that post-operative radiotherapy was prescribed only to patients with pathologically positive lymph nodes. 相似文献
65.
66.
Aortic disease can present as an acute chest pain syndrome. Although aortic dissection is the most common etiology, other processes such as intramural hematoma (IMH) and penetrating atherosclerotic ulcers are being increasingly recognized. They can all be accurately identified by computed tomography (CT) imaging or transesophageal echocardiography. The overlap between these processes regarding definition and mechanism is controversial. Treatment for all three conditions has thus far been dictated by location, wherein ascending or arch involvement (Stanford type A) necessitates surgery and descending disease (type B) is treated medically. Small studies suggest that subgroups of type A IMH may be treated medically with good outcomes. 相似文献
67.
Sarah Ford MSc Psych D PhD Theo Schofield MA BM BCh FRCP FRCGP † Tony Hope MA PhD FRCPsych ‡ 《Health expectations》2006,9(2):130-137
OBJECTIVE: To investigate opportunities for, and types of decision making in the general practice (primary care) consultation, and examine differences in skills of those doctors who are successful at meeting their patients' preferences and those who are less successful. DESIGN: Observation study of doctor-patient consultations in general practice. PARTICIPANTS: Patients attending for routine appointments in 12 general practice surgeries across Oxfordshire. METHODS: A total of 212 doctor-patient consultations were video-recorded. The patients involved completed a questionnaire to elicit their perceptions of how decisions were made. The video-taped recordings were coded with a new instrument, the Evidence Based Patient Choice Instrument (EBPCI), to classify the number and type of decision-making opportunities arising during each consultation. A total of 149 recordings were coded using the Oxbridge Rating Scale to assess the doctors' consultation styles. RESULTS: There was a range of decision-making opportunities in addition to those involving medical treatment. With the exception of 'fitness for work', decisions were generally 'doctor led'. There was only moderate agreement between patient perceptions of their level of involvement in decision making and the objective ratings using the EBPCI. There was wide variation in the ability of doctors to meet their patients' preferences for involvement. CONCLUSIONS: There are many decisions made in primary care consultations, in addition to those about medical treatments, in which patients could be involved to a greater extent than they currently are. Some doctors are significantly better than others at meeting different patients' preferences for their decision-making role. Patients' perceptions of shared decision making appears to be influenced by the doctors' general consultation skills. 相似文献
68.
69.
Simon Jackson BA BM BCh Tony Hollingworth FRCS MRCOG PhD Marion Macpherson MRCOG MD 《The Australian & New Zealand journal of obstetrics & gynaecology》1993,33(2):214-215
Summary: A case report is described in which abdominal pregnancy was misdiagnosed by ultrasound scanning as a pregnancy within a horn of a bicornuate uterus. Two serum alpha fetoprotein (SAFP) results were greatly elevated and an amniocentesis was performed, the liquor alpha fetoprotein (LAFP) and karyotype were normal. Elective Caesarean section was performed at 38 weeks for a persistent transverse lie and an abdominal pregnancy was found. The outcome was excellent for both the mother and child.
This is the first reported case of amniocentesis and measurement of LAFP in an abdominal pregnancy and confirms abdominal pregnancy as a rare cause of an elevated SAFP. 相似文献
This is the first reported case of amniocentesis and measurement of LAFP in an abdominal pregnancy and confirms abdominal pregnancy as a rare cause of an elevated SAFP. 相似文献
70.
The main purpose of this study was to compare rectal and axillary temperature measurements in African children. Altogether 573 sick children were seen in an outpatient setting in rural West Africa. Rectal and axillary temperatures were measured and the parent or guardian was asked if they thought that the child had a raised body temperature. Normal ranges were defined from an age matched population of 203 healthy children. A raised axillary temperature predicted a raised rectal temperature with a sensitivity of 98% and a specificity of 88%. The parents' impression that their child had a fever was a less sensitive (89%) and less specific (59%) indicator of raised rectal temperature. A raised axillary temperature is a good screening test for a raised rectal temperature in African children. 相似文献