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排序方式: 共有2461条查询结果,搜索用时 15 毫秒
91.
92.
Carriage of Haemophilus influenzae and Streptococcus pneumoniae in healthy Chinese and Vietnamese children in Hong Kong 总被引:1,自引:0,他引:1
RYT Sung JM Ling SM Fung SJ Oppenheimer DW Crook JTF Lau AFB Cheng 《Acta paediatrica (Oslo, Norway : 1992)》1995,84(11):1262-1267
Nasopharyngeal carriage of Haemophilus influenzae and Streptococcus pneumoniae was studied in 621 healthy Chinese children and 300 healthy Vietnamese children aged from 2 months to 5 years in Hong Kong. The carriage rate of H, influenzae type b in Vietnamese children was 1.3% (CI 0.04-2.63%); it was zero in Chinese. The carriage rate of non-typable H. influenzae was 5.8% (CI 1.4-7.6%) in Chinese and 65.4% (CI 58.9-69.8%) in Vietnamese. The carriage rates of S. pneumoniae were 10.8% (CI 8.3-13.2%) and 55.7% (CI 50.1-61.3%) in Chinese and Vietnamese children, respectively. Univariate and multivariate logistic regression analyses were performed to search for factors associated with differences in carriage rates of both H. influenzae and S. pneumoniae between Chinese and Vietnamese children. Although older age, smaller living area and parental smoking were associated with higher carriage rates, these could not explain the remarkably low carriage rates of both bacteria in Chinese children. 相似文献
93.
We report cerebral blood flow (CBF) values for healthy neonates in five gestational age categories for 9 single and 7 combination measures of continuous wave Doppler ultrasound. Combinations of measures, particularly those from the anterior cerebral artery with a 5.0 MgH probe, increased the reliability and validity. The most reliable and valid single measure was mean flow velocity from the anterior cerebral artery (5.0 MgH probe). CBF values were lower for neonates with respirator support than for neonates without respirator support. No significant differences were found in CBF measures between intubated neonates who developed IVH and intubated neonates who did not develop IVH. Neonates who were intubated and developed intraventricular hemorrhage (IVH) were treated more vigorously than those who were intubated and did not develop IVH. By day 6, neonates with IVH had a significantly higher mean pH, mean serum bicarbonate, and mean positive base balance. 相似文献
94.
Evaluation of the preterm infant for patent ductus arteriosus 总被引:5,自引:0,他引:5
R C Ellison G J Peckham P Lang N S Talner T J Lerer L Lin K J Dooley A S Nadas 《Pediatrics》1983,71(3):364-372
As a first step in a multicenter, collaborative project to study the role of indomethacin in the management of patent ductus arteriosus in premature infants, a diagnostic scheme was developed, on an a priori basis, by a consensus of the participating neonatologists and pediatric cardiologists. The scheme, which utilizes clinical and noninvasive findings, was designed to detect infants with a "hemodynamically significant" patent ductus arteriosus (PDA). Among 1,689 infants with birth weight less than 1,750 g who were monitored during the first year of the study, 342 (20.2%) met the criteria for PDA. Rates were higher for smaller infants (42% with birth weight less than 1,000 g) than for larger infants (7% with birth weight 1,500 to 1,750 g). Although study protocol did not require a direct procedure to confirm the diagnosis of PDA, a marked decrease in the presence of most criteria was noted following surgical ligation of the ductus. Although the echocardiographic criterion (ratio of left atrium to aorta [LA/Ao] greater than or equal to 1.15) proved to have a low specificity for PDA, the data suggest that the overall scheme led to a very low rate of false-positive diagnosis. Following the application of the scheme for 1 year at 13 clinical centers, it has been shown to be a highly acceptable means of detecting infants with PDA. 相似文献
95.
Mao B Abrahim A Ge Z Ellison DK Hartman R Prabhu SV Reamer RA Wyvratt J 《Journal of pharmaceutical and biomedical analysis》2002,28(6):1101-1113
Rofecoxib is a highly active and selective cyclo-oxygenase II inhibitor. A stability-indicating method for the assay of rofecoxib has been developed using reverse-phase high-performance liquid chromatography (HPLC). Stress testing of rofecoxib was conducted during the method development and validation. HPLC analysis of rofecoxib solutions stressed under alkaline and photolytic conditions revealed the presence of several degradates. Two main degradates were determined to be the cyclization product formed by photo-cyclization and the dicarboxylate formed by ring opening in the presence of base and oxygen. The identities of these degradates were confirmed by comparison of UV spectra and HPLC retention time with the independently synthesized products. The mechanistic pathways for the formation of these degradates are discussed. Further improvement of the HPLC method's ruggedness has been made based on these studies. 相似文献
96.
Hopkins PN Heiss G Ellison RC Province MA Pankow JS Eckfeldt JH Hunt SC 《Circulation》2003,108(5):519-523
97.
Determinants of the availability and accuracy of self-reported birth weight in middle-aged and elderly women 总被引:4,自引:0,他引:4
Allen DS Ellison GT dos Santos Silva I De Stavola BL Fentiman IS 《American journal of epidemiology》2002,155(4):379-384
Associations have been found between birth weight and many diseases in adult life. In most countries, few birth records exist for older adults; therefore, birth weight is usually obtained by maternal recall or self-report. This study examined determinants of the availability and accuracy of self-report in middle-aged and elderly women. Birth weights, recorded at the time of birth, were found in 1999 for a subset of 363 women participating in a long-running cancer research study in the United Kingdom. Questionnaires were sent to the surviving 286 women requesting information on their birth weight and other factors related to their birth family. Twenty-five percent of the 244 respondents were able to report their birth weight to within 4 ounces (113.4 g) of that listed in birth records, 28% reported it inaccurately, and 47% did not know their birth weight. The most important factors determining the availability of self-reported birth weight were having a living mother and a low birth weight (< or = 6 pounds (2,722 g)). The most important determinants of accuracy, for those who provided a report, were being younger and the eldest child. Research studies relying on self-reported birth weight should take these factors into account. 相似文献
98.
Ellison GT 《Social science & medicine (1982)》2002,54(4):561-576
The relative income hypothesis interprets statistical associations between income inequality and average health status at the population level, as evidence that income inequality has a deleterious psychosocial effect on individual health. An alternative explanation is that these, population-level associations, are statistical artefacts of curvilinear, individual-level relationships between income and health. Indeed, provided the cost-benefit ratio of health-enhancing goods and services vary, the law of diminishing returns should produce curvilinear, asymptotic relationships between income and health at the individual level, which create ('artefactual') associations between income inequality and health at the population level. However, proponents of the relative income hypothesis have argued that these relationships are unlikely to be responsible for the associations observed between income inequality and average health status amongst high-income populations. In these populations, the individual-level relationships between income and health would be nearer their asymptotes, where a shallower slope should ensure that income inequality has little (if any) 'artefactual' effect on average health status. Yet this argument was based on analyses of population-level data which underestimated the slope and curvilinearity of underlying, individual-level relationships between income and health. It is therefore likely that (at least some part of) the population-level associations between income inequality and average health status (amongst low-, middle- and high-income populations) are 'artefacts' of curvilinear, individual-level relationships between income and health. Nevertheless, it is also possible that income inequality is somehow (partly or wholly) responsible for the curvilinear nature of individual-level relationships between income and health. Likewise, it is possible that income inequality alters the height, slope and/or curvilinearity of these relationships in such a way that income inequality has an independent effect on individual health. In either instance, the 'artefactual' effect of curvilinear relationships between income and health at the individual level would simply reflect the mechanism underlying the relative income hypothesis. 相似文献
99.
Grazyna Jasienska Maria Kapiszewska Peter T Ellison Malgorzata Kalemba-Drozdz Ilona Nenko Inger Thune Anna Ziomkiewicz 《Cancer epidemiology, biomarkers & prevention》2006,15(11):2131-2135
Variation in the levels of sex-steroid hormones results from differences in developmental conditions, adult lifestyle, and genetic polymorphism. Genes involved in sex-steroid biosynthesis have been implicated to influence levels of hormones in premenopausal women, but the results were inconclusive. We tested variation among women in levels of salivary estradiol (E(2)) corresponding to CYP17 genotypes. CYP17 encodes cytochrome P450c17alpha, which mediates two enzymes important in E(2) synthesis. In contrast to the earlier studies that relied on one or a few samples for assessing the E(2) levels of an individual woman, our study is based on daily collected saliva samples for one entire menstrual cycle. Sixty Polish women, ages 24 to 36 years, with regular menstrual cycles and no reported fertility problems participated in the study. Women with A2/A2 genotype had 54% higher mean E(2) levels than women with A1/A1 genotype (P = 0.0001) and 37% higher than women with A1/A2 genotype (P = 0.0008). Heterozygous A1/A2 women had 13 % higher E(2) levels than homozygous A1/A1 women (but this difference was significant only in a nonparametric test). Levels of E(2) during the day with highest E(2) (day -1) were 72% higher in A2/A2 compared with A1/A1 (P = 0.01) and 52 % higher compared with A1/A2 (P = 0.03). Our results suggest that CYP17 genotype may serve as a biomarker of endocrine function in women of reproductive age. (Cancer Epidemiol Biomarkers Prev 2006;15(11):2131-5). 相似文献