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991.
992.
A series of nonsteroidal compounds, 2-(p-chlorobenzyl)-3-aryl-6- methoxybenzofurans derived from the 2-(p-chlorobenzyl)-6-methoxy-3(2H)-benzofuranones has been synthesized. The key steps in the synthesis were reactions of 2-(p-chlorobenzyl)-6-methoxy-3(2H)-benzofuranones with the arylorganometallic reagents followed by dehydration of the resulting carbinols. The benzofurans are ligands for antiestrogen-binding sites (AEBS) and display no significant interaction with the estrogen receptor (ER). All bind to AEBS with equivalent or greater affinity than tamoxifen. These compounds decrease [3H]thymidine incorporation in AEBS-containing EL4 lymphoid cells and MCF7 breast cancer cells in a concentration-dependent manner between 10(-8) and 10(-6) M and are generally more inhibitory than tamoxifen. In contrast, they have no effect on [3H]thymidine incorporation by an AEBS-deficient variant of the MCF7 cell line, RTx6. The present findings of (1) selective and high affinity binding of the benzofurans to AEBS, (2) their concentration-dependent inhibition of [3H]thymidine incorporation in AEBS-containing cells, and (3) their lack of antiproliferative effect in an AEBS-deficient cell line suggest a functional role for AEBS in mediating the antigrowth effect of these compounds. Two of the more active benzofuran compounds also significantly inhibited de novo cholesterol biosynthesis in EL4 cells which lack ER. This effect could be obtained after 5 h of treatment and preceded significant loss of cell viability. This is the first demonstration that selective ligands of AEBS (other than the known nonsteroidal antiestrogens) interfere with cholesterol biosynthesis-an action that may contribute to their antigrowth effect. 相似文献
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995.
J. A. Reis Neto J. A. Reis Jr O. Kagohara J. Simões Neto 《Techniques in coloproctology》2005,9(2):159-161
The concept that hemorrhoidal disease is a consequence
of disorders of the cephalic portion of the anal
canal, i.e. weakness of the vascular cushions and the connective
tissue, is the basis for modifing the usual surgical
technique in many aspects. The two main differences of
the method described are: (i) the internal plexus is treated
by parceled ligature, avoiding resection of the mucosa, but
providing a firm fixation of the submucosa and subsequent
fixation of the anal epithelium to the underlying
sphincter in the anal canal; (ii) the external plexus is
removed preserving as much as possible the anal margin
skin, and the resulting wound is partially closed, resulting
in a small drainage area; and (iii) a firm fixation of the
submucosa and subsequent fixation of the anal epithelium
to the underlying sphincter are achieved without mucosa
resection. 相似文献
996.
Sim MG 《The Medical journal of Australia》2007,187(1):55; author reply 56-55; author reply 57
997.
Renal tuberculosis in adult polycystic kidney disease: report of 2 cases and review of the literature 总被引:1,自引:0,他引:1
Simões do Espírito Santo K Teixeira Vde P Costa Hde O Franco M 《International journal of surgical pathology》2007,15(2):196-198
Adult polycystic kidney disease (APKD) is a common and potentially fatal disease, leading to end-stage renal failure in 50% of cases. The disease is frequently complicated by arterial hypertension, bacterial pyelonephritis, and hematuria. The association between APKD and tuberculosis has rarely been reported and is related to a more unfavorable course since the infection becomes refractory to specific treatment. The authors report 2 cases of renal tuberculosis diagnosed in the native nephrectomy specimens of 2 patients with APKD after renal transplantation. Tuberculosis, although not common, must be recognized as a potential source of infection of native polycystic kidneys in immunocompromised transplant recipients. 相似文献
998.
Young Ho Yun MD Yaeji Kim MA Jin A. Sim MS Soo Hyuk Choi BA Cheolil Lim PhD Joon‐ho Kang PhD 《The Journal of school health》2018,88(8):569-575
BACKGROUND
The objective of this study was to develop the School Health Score Card (SHSC) and validate its psychometric properties.METHODS
The development of the SHSC questionnaire included 3 phases: item generation, construction of domains and items, and field testing with validation. To assess the instrument's reliability and validity, we recruited 15 middle schools and 15 high schools in the Republic of Korea.RESULTS
We developed the SHSC questionnaire of 158 items categorized into 5 domains: (1) Governance and Infrastructure, (2) Need Assessment, (3) Planning, (4) Health Prevention and Promotion Program, and (5) Monitoring and Feedback. All SHSC domains and subdomains demonstrated acceptable reliability with good internal consistency. Each domain and subdomain except for “Planning” was associated significantly with students' health status. Most subdomains, including school health philosophy, school policy, communication, the evaluation system, and monitoring, were significantly and negatively associated with student absence.CONCLUSIONS
The SHSC shows significant association with the overall student health and can be useful in assessing comprehensive school health programs.999.
Chhavi Raj Bhatt Mary Redmayne Michael J. Abramson Malcolm R. Sim Christopher Brzozek Berihun M. Zeleke Geza Benke 《Australasian physical & engineering sciences in medicine / supported by the Australasian College of Physical Scientists in Medicine and the Australasian Association of Physical Sciences in Medicine》2018,41(4):985-991
The aims of this study were to evaluate the weekly and annual cumulative radiofrequency-electromagnetic field (RF-EMF) exposure attributed to mobile phone (MP) use, and assess whether a novel app (Quanta Monitor?) could be employed in a small human sample to characterise the RF-EMF exposures associated with the use of MPs. Ten participants provided their two months’ daily objective data on their MP exposures (i.e. transmitted and received power densities) attributed to different modes of MP usage such as cellular calls, cellular data and Wi-Fi. The results demonstrated that total transmitted power density (cellular phone calls, data and Wi-Fi surfing) could be many orders of magnitude higher than that from the total received power density. Of the total transmitted power density, cellular data use contributed the largest portion. Our study showed that Quanta Monitor? could be employed in prospective assessment of exposures to MPs in epidemiological studies. 相似文献
1000.
Reis MF Sampaio C Brantes A Aniceto P Melim M Cardoso L Gabriel C Simão F Miguel JP 《International journal of hygiene and environmental health》2007,210(3-4):439-446
Human exposure to heavy metals makes it necessary to monitor these elements in the human body if the objective is to relate heavy metal exposure to adverse health effects. In Portugal, biomonitoring projects on heavy metals are being carried out on people living in the vicinity of solid waste incinerators. The projects are being developed in the ambit of two environmental health surveillance programs related to solid waste incineration facilities, one near Lisbon and the other on Madeira Island, that have the main objective of guaranteeing the safeguard of public health in relation to the potential negative impact of incineration processes on human health. These programs are the only ones in the country that integrate a systematic observation of human exposure to heavy metals as determined by the respective body burden in several population groups. Therefore, they are the only ones that are currently able to provide systematic data from Portuguese regions on the extent and pattern of human exposure to this type of pollutants. The present paper is the first of a series of three prepared papers with the objective of presenting and discussing available data. It addresses exposure to lead, cadmium and mercury as determined by their levels in blood of general population adults. Results suggest the effectiveness of source control measures in relation to both incinerators under study, similarly to what has been concluded from previous studies addressing exposure to dioxins. They also show, in relation to the baseline situation, a general significant trend for reduction of exposure to all studied heavy metals. Individuals from Lisbon seem to have a significantly higher body burden of the studied metals than those living in Madeira and, in general, metal exposure in men is significantly higher than in women, with the most relevant exception being the case of higher mercury levels in women, at the baseline and for both communities. Compared with published reference values for similar conditions, blood levels of cadmium, lead, and mercury of the present investigation seem to be relatively higher, in median terms and for extreme values, mainly in the case of cadmium and mercury. In the case of lead the differences are not so marked. 相似文献