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81.
The effect of lysozyme on the complement-dependent bactericidal action of different antibody classes. 下载免费PDF全文
Preparations of rabbit, dog and sheep IgA, IgA and IgM were examined for their antibacterial effects using a complement-dependent bactericidal assay. IgM and IgG were effecient bactericidal antibodies in the presence of complement; IgA, however, contained negligible activity. Except for sheep IgG no enhancement of bactericidal activity was observed in the presence of added lysozyme. 相似文献
82.
John R. Steele Sean P. Ryan William A. Jiranek Samuel S. Wellman Michael P. Bolognesi Thorsten M. Seyler 《The Journal of arthroplasty》2021,36(5):1729-1733
BackgroundRevision total knee arthroplasty (TKA) involves varying levels of case complexity and costs depending on the following: (1) number of components revised, (2) duration of operating room time, and (3) length of hospital stay. However, the cost associated with different types of aseptic TKA revisions, based on number and type of components revised, is not well described. We sought to determine differences in cost associated with different revision types, and to correlate this with average national hospital and surgeon reimbursement based on current Centers for Medicare and Medicaid Services data.MethodsThis is a retrospective review of aseptic revision TKAs performed at a single tertiary referral center from 2015 to 2018. Patient demographic data, operating room time, and direct surgery and total hospital costs obtained from an internal accounting database (Enterprise Performance Systems, Inc) were collected. Patients were stratified by the components revised (polyethylene liner only, tibia only, femur only, or both femur and tibia). We hypothesized that direct surgery and total hospital costs would increase as case complexity increased from poly exchange to single-component revisions and both-component revisions.ResultsIn total, 106 patients were included (19 poly exchanges, 10 tibia-only revisions, 13 femur-only revisions, and 64 both-component revisions). Operating room time was significantly lower for poly exchange than all other groups (P < .001). Direct surgery and total hospital costs were significantly lower for poly exchange than all other groups (P < .001), and were significantly lower for tibia-only and femur-only revisions compared to both-component revisions (P < .001). Average national surgeon reimbursement by Medicare decreased as a percentage of direct surgery cost as case complexity increased from poly exchange to tibia-only, femur-only, and both-component revisions. Total hospital cost per average Diagnosis Related Group weight was lowest for single-component revisions and highest for both-component revision.ConclusionThere are significant differences in cost associated with aseptic TKA revisions based on number and type of components revised. These differences may not be accurately reflected in reimbursement, and often represent a burden to those who treat complex revisions. 相似文献
83.
Large numbers of patients are being treated for myopia, hyperopia, and astigmatism using the excimer laser. For many patients who are treated for myopia and hyperopia, the procedure is elective and these treatments remain investigational. The use of other lasers for refractive surgery is at an earlier stage, with human trials commencing for infrared lasers. Animal studies are being performed for pulsed picosecond and solid-state ultraviolet lasers. The indications for refractive treatment should be clearly defined, although the results of laser application remain the subject of investigation. Complications of laser application to the cornea occur in the immediate, short-term, and long-term posttreatment period. A continual improvement in refractive results along with a reduction in complications remains the goal of laser refractive research. 相似文献
84.
Have you been taking your pills? The adherence-monitoring sequence in the medical interview 总被引:6,自引:0,他引:6
This paper employs qualitative, sociolinguistic techniques to identify and describe the kinds of conversational strategies that primary care physicians use to assess patient adherence to antihypertensive regimens. Three general approaches are described: indirect inquiry, simple direct questions, and information-intensive inquiry. The strengths and weaknesses inherent in these discourse categories are discussed. Qualitative assessment, coupled with the results of a pilot study investigating the effectiveness of naturally occurring instances of these three general styles, leads to the conclusion that how one asks "Have you been taking your medications?" is consequential for the accurate diagnosis and management of adherence problems. 相似文献
85.
Claudia Schwab John C. Steele Haruhiko Akiyama Edith G. McGeer Patrick L. McGeer 《Acta neuropathologica》1995,90(3):287-298
The Chamorro population of the island of Guam is highly susceptible to a disease called lytico-bodig (LB), wich clinically resembles a mixture of amyotrophic lateral sclerosis (ALS), Parkinson's disease (PD) and Alzheimer disease (AD). The disease is characterized by the widespread development of neurofibrillary tangles in the central nervous system. These tangles have an immuno-histochemical profile indistinguishable from that seen in AD. We studied by immunohistochemistry the occurrence of intracellular and extracellular neurofibrillary tangles in LB in the entorhinal cortex, hippocampus and substantia nigra using antibodies to tau protein and ubiquitin. We also studied the relationship of these tangles to amyloid precursor protein (APP) and its -amyloid fragment (BAP), using multiple antibodies to BAP and other APP sequences. In advanced cases of LB, the development of neurofibrillary tangles was far more severe than in advanced cases of AD. Virtually all neurons of CA-1 and the subiculum were lost and only ghost tangles remained. In areas dominated by such extracellular tangles, BAP deposits were frequently observed developing around the fibers of ghost tangles. In some cases, the deposits covered only a few of the fibers, but in others, they seemed to envelope the complete tangle. The deposits were thiolavin S and Congo red positive, indicating that the BAP was in a consolidated form. We describe these entities as tangle-associated amyloid deposits. Such BAP deposits have previously eeen described in some cases of AD, dementia pugilistica and LB. However, we found them in all cases of LB with dementia in the hippocampal-entorhinal areas and in most cases in the substantia nigra. They do not evolve from diffuse BAP deposits since they are remote from them, and they do not trap dystrophic neurites. The fact that extracellular tangle material can act as a nidus for BAP build-up in LB suggests that further consideration needs to be given to the ways in which extracellular BAP deposits are formed. 相似文献
86.
87.
This article uses linked data from the 1995 Morocco DHS calendar and the 1992 Morocco DHS service-availability module to study the effect of service environment on contraceptive discontinuation, switching, and adoption of a modern method following a birth. The 1995 Morocco DHS also collected information on the source of supply for each episode of use of a modern method recorded in the calendar, allowing study of the association between the source of supply and discontinuation and switching rates. Multilevel event-history models are used to evaluate the impact of individual-level sociodemographic characteristics and community-level indicators of family planning service provision. The findings show that the presence of a nearby public health center is associated with higher modern-method adoption after a birth and lower method-failure rates; the presence of a pharmacy is associated with lower discontinuation due to side effects or health concerns. The degree of method-choice potential has a positive impact on both the rate of switching from the pill to another modern method and on modern-method adoption after a birth. 相似文献
88.
Stewart MG Cristol D Philips R Steele RJ Stamatakis A Harrison E Clayton N 《Behavioural brain research》1999,98(1):89-94
In two species of birds, food-storing marsh tits, P. palustris, and non-storing blue tits, P. caeruleus, quantitative receptor autoradiography was used to localize NMDA (N-methyl-D-aspartate)-sensitive [3H]glutamate, [3H]MK801, and [3H]AMPA binding sites, in six regions of the forebrain: hippocampus and parahippocampus, hyperstriatum accessorium (vision) and ventrale (sensory integration), neostriatum (auditory), and lobus parolfactorius (basal ganglia). In both species high levels of labelling to both NMDA and AMPA receptors were observed throughout the forebrain. However, a marked difference in receptor labelling was apparent between the two species, with levels of binding to NMDA ion channel sites being significantly lower (20%) in both the hippocampus and parahippocampus, in food storers compared to non-food storers. The levels of binding to other forebrain regions were remarkably similar in the two species. No differences were seen in the binding to AMPA receptors in forebrain regions of either species. 相似文献
89.
90.
Ultrasound densitometry has been measured in the os calcis of 31 stroke patients (14 women, 17 men), ages 46–87 years, to
determine whether bone density is lower than expected for normal subjects at this site, and to investigate whether or not
the stroke side has lower values than the nonstroke side. We have also measured a large control group of 268(39 men, 228 women)
subjects who showed similar values to other published data. Immobility is a known precursor to bone loss and so we also compared
ultrasound Stiffness Index with an index of mobility in 22 of the stroke patients. In healthy subjects, ultrasound densitometry
(measured as Stiffness) fell by 25% in females from 48–52 to 68–72 years. Stiffness (expressed as z-score) in patients with
stroke was low in females (P < 0.02) but not in males, but both stroke side and nonstroke side were equally low. Stiffness did not decline with time since
stroke, but did correlate with mobility after stroke, on the stroke (r = 0.73) and nonstroke (r = 0.62) side. The data suggest
that stroke patients, particularly females, have low bone density before the stroke event. The greater ultrasound Stiffness
with increasing mobility after stroke may suggest that active rehabilitation after stroke may produce denser bone.
Received: 30 July 1997 / Accepted: 10 June 1999 相似文献