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The regulation of toxic substances present in the environment requires that carcinogens be distinguished from noncarcinogens on the strength of the available toxicological and epidemiological evidence for carcinogenicity. In this article, we consider the difficulties associated with establishing strong evidence against carcinogenicity. In particular, the ability of both animal and human studies to detect small increases in tumor occurrence rates is evaluated in statistical terms. Consideration is also given to resolving apparent conflicts between the toxicological and the epidemiological sources of data. 相似文献
3.
A national hospital/community model protocol was developed for the forensic and medical examination of victims of sexual assault. This review is designed to assist states in the development of sexual assault protocols. Controversial issues were addressed, including the collection of hair evidence, the importance of semen, mandatory reporting, pregnancy testing and prophylaxis, and sexually transmitted diseases including human immunodeficiency virus. The current role of DNA profiling is reviewed. These issues at the interface of medicine, forensic science, victim advocacy, and the law are analyzed. Representatives of the medical, legal, law enforcement, victim advocacy, and forensic science communities contributed to the development of the protocols at the national and state levels. The importance of a collaborative effort is emphasized. The broad protocol goals are to minimize the physical and psychological trauma to the victim while maximizing the probability of collecting and preserving physical evidence for potential use in the legal system. 相似文献
4.
J Goddard 《Journal of medical entomology》1992,29(3):501-506
Adult Ixodes scapularis Say were collected weekly during two fall-winter-spring seasons from 1989 to 1991 to assess their temporal and spatial distribution as well as the effects of several meteorologic parameters on questing activity. Collections were made in three 0.4-ha sites in central Mississippi by flagging vegetation with a white flannel cloth. Adult I. scapularis were collected from 25 October through 11 April during the 1989-1990 season and 24 October-1 April in the 1990-1991 season. Peak I. scapularis questing activity occurred on 5 February and 4 February during the two seasons, respectively. Ticks were collected most often at approximately 20 degrees C but seven were collected on a day when the temperature was 6.9 degrees C. Ticks were clustered within the study sites and not evenly distributed. Most I. scapularis were collected from Ligustrum sinense and Chasmanthium sessiliflorum at a height of 31-40 cm. Statistical analyses of the meteorologic factors that affect questing activity are presented and discussed. 相似文献
5.
Acute arsenic intoxication may present as Landry-Guillain-Barré syndrome because of similarities in clinical symptoms involving the gastrointestinal tract, weakness, and sensory symptoms. Electrodiagnostic findings may be similar with demyelinating changes predominating early in both diseases. A case is presented of repeated arsenic poisoning over two years misdiagnosed as Landry-Guillain-Barré syndrome. Proximal F-loop latency (M-wave latency at wrist + F-wave latency at wrist - 2 M-wave latency at axilla) helped to establish the correct diagnosis. Serial electrodiagnostic studies were done documenting the evolution of chronic repeated arsenic poisoning from a picture showing demyelination to one with severe axonal loss. 相似文献
6.
Blanton RE Salam EA Ehsan A King CH Goddard KA 《European journal of human genetics : EJHG》2005,13(5):660-668
A minority of individuals infected with the parasite Schistosoma mansoni develops hepatic fibrosis. HLA studies in Egypt and a candidate gene search in a Sudanese population indicate that the host's genetics contribute to disease susceptibility. In an Egyptian community, 32.7% of individuals 11 years and older had significant fibrosis by WHO ultrasound criteria. Linkage to 10 candidate genes was tested using 89 affected sibling pairs from 40 pedigrees in this community. The candidates included genes that initiate fibrosis, participate in collagen synthesis, or control collagen degradation. Two to four single-nucleotide polymorphisms (SNPs) were genotyped per locus, and 188 individuals were genotyped at 48 markers. Model-free modified Haseman-Elston analysis identified linkage to a SNP in the interferon gamma receptor locus (P=0.000001). There was also weak evidence for linkage to the interleukin 13-4 region and tissue growth factor beta 1. 相似文献
7.
Jabulani R. Ncayiyana Leonardo Martinez Elizabeth Goddard Landon Myer Heather J. Zar 《Nutrients》2021,13(5)
Early-life vitamin D deficiency is associated with adverse child health outcomes, but the prevalence of vitamin D deficiency and its correlates in infants remains underexplored, particularly in sub-Saharan Africa. We aimed to investigate the prevalence of vitamin D deficiency and its correlates among young infants in South Africa. This study included 744 infants, aged 6–10 weeks from the Drakenstein Child Health Study, a population-based birth cohort. Infants were categorized into distinct categories based on serum 25(OH)D concentration level including deficient (<50 nmol/L), insufficient (50–74 nmol/L), and sufficient (≥75 nmol/L). Using multivariable Tobit and logistic regression models, we examined the correlates of serum 25(OH)D3 levels. The overall prevalence of vitamin D deficiency was 81% (95% confidence intervals (CI]) 78–83). Multivariable regression analysis showed that serum 25(OH)D3 concentration was independently associated with study site, socioeconomic status, and sex. Birth in winter and breastfeeding were the strongest predictors of lower serum 25(OH)D3 concentration levels. Compared to non-breastfed children, children breastfed were at higher risk of vitamin D deficiency (AOR, 1.96; 95% CI, 1.04–3.67) and breastfeeding for more than one month was associated with greater likelihood of vitamin D deficiency (AOR, 5.40; 95% CI, 2.37–12.32) and lower vitamin D concentrations (−16.22 nmol/L; 95% CI, −21.06, −11.39). Vitamin D deficiency in infants is ubiquitous, under-recognised, and strongly associated with season of birth and breastfeeding in this setting. Nutritional interventions with vitamin D supplementation in national health programs in low- and middle-income countries are urgently needed to improve early-life vitamin D status in infants. 相似文献
8.
Dan Liu Maria Lucia Pace Maria Goddard Rowena Jacobs Raphael Wittenberg Anne Mason 《Health economics》2021,30(1):36-54
Since 2010, adult social care spending in England has fallen significantly in real terms whilst demand has risen. Reductions in social care supply may also have impacted demand for NHS services, particularly for those whose care is provided at the interface of the health and care systems. We analyzed a panel dataset of 150 local authorities (councils) to test potential impacts on hospital utilization by people aged 65 and over: emergency admission rates for falls and hip fractures (“front‐door” measures); and extended stays of 7 days or longer; and 21 days or longer (“back‐door” measures). Changes in social care supply were assessed in two ways: gross current expenditure (per capita 65 and over) adjusted by local labor costs and social care workforce (per capita 18 and over). We ran negative binomial models, controlling for deprivation, ethnicity, age, unpaid care, council class, and year effects. To account for potential endogeneity, we ran instrumental variable regressions and dynamic panel models. Sensitivity analysis explored potential effects of funding for integrated care (the Better Care Fund). There was no consistent evidence that councils with higher per capita spend or higher social care staffing rates had lower hospital admission rates or shorter hospital stays. 相似文献
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10.
Radiation doses from CT in the Sultanate of Oman 总被引:6,自引:0,他引:6
The computed tomography dose index (CTDI), dose-length product (DLP) and the effective dose were determined for a range of CT examinations in the Sultanate of Oman. There was a wide variation in CTDI. This shows that there is a variation in both scanner design and the exposure settings used by hospitals. There was also a wide variation in DLP and effective dose, suggesting that in some cases too many slices are taken. Therefore, standard protocols should be designed and adhered to in order that radiation doses may be reduced in the future. 相似文献