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31.
Martin Orrell Robert Howard Andrew Payne Klaus Bergmann Robert Woods Brian S. Everitt Raymond Levy 《International journal of geriatric psychiatry》1992,7(4):263-275
One hundred and sixty-four patients admitted to a psychogeriatric unit were given a combination of four different cognitive tests: the Mini Mental State Examination (MMSE), the Abbreviated Mental Test Score, The Felix Post Unit Score and the compilation of tests recommended by the MRC Alzheimer's Disease Workshop. The tests were compared with respect to their ability to sort accurately cases of dementia and depression, and the effects of age and education on test score and misclassification rate with diagnosis controlled for. The MMSE had a very high misclassification rate for the poorly educated and depressed group. The logistical discriminant functional analysis selected only eight items as the best discriminators between organic/ functional or dementia/depression groups. Only one of these eight was not either a memory or orientation test. The value of simply adding up tests of different aspects of cognitive function in dementia assessment or screening is questioned. 相似文献
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Helen E. Pearson Donna L. Smith-Harrison Nancy K. Rosenblatt Bertram R. Payne 《Experimental neurology》1993,119(2)
The short-term metabolic response of immature retinal ganglion cells to destruction of their target cells in the dorsal lateral geniculate nucleus (dLGN) was assessed in newborn cats. Retrograde degeneration of virtually all dLGN cells was induced by ablation of the 13 contiguous areas of visual cortex on the day of birth. The metabolic response of retinal ganglion cells to this loss of target cells in dLGN was determined by exposing the ganglion cell layer to tritiated uridine, a precursor of RNA. Control measurements were made from unoperated littermates. Following sectioning and processing of the retinae from both groups of kittens for autoradiography, silver grain densities overlying the cellular profiles in the ganglion cell layer were calculated. These calculations revealed levels of uridine incorporation at Postnatal Day 4 in both groups of kittens significantly higher than at either Postnatal Day 2 or 7, but no significant differences between the two groups on any day examined. These results show that the level of RNA synthesis in retinal ganglion cells increases temporarily during the first postnatal week and that this synthesis is unaffected by the death of target cells in the dLGN. The temporary increase may be related to the establishment of synaptic connections on retinal ganglion cells by their afferent bipolar and amacrine neurons in the inner nuclear layer. 相似文献
34.
Protein antigen-monoclonal antibody contact sites investigated by limited proteolysis of monoclonal antibody-bound antigen: protein "footprinting" 总被引:9,自引:3,他引:6 下载免费PDF全文
H Sheshberadaran L G Payne 《Proceedings of the National Academy of Sciences of the United States of America》1988,85(1):1-5
This study describes the use of limited proteolysis of monoclonal antibody (mAb)-bound antigens in the analysis of the two measles virus surface glycoproteins. This approach is dubbed protein "footprinting" in analogy with DNA "footprinting." Protein footprinting was superior to competitive-binding assays and as good as in vitro mAb-selected variant analysis in differentiating among mAbs with various specificities to a given protein. Proteolytic digestion of the antigen prior to mAb binding drastically reduced mAb binding resulting in poor differentiation among mAbs. In contrast, protein footprinting showed that some mAbs retained the ability to immunoprecipitate such fragments. Thus footprinting could be used for localization of mAb epitopes on a protein and proved also to be an effective means of distinguishing among mAb-selected variants differing in single epitopes. Conformational changes caused by heat-denaturation or the binding of anti-antibody to an antigen-antibody complex could also be detected by footprinting. 相似文献
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Primm BJ Perez L Dennis GC Benjamin L Clark W Keough K Leak WD Payne R Smith D Sullivan LW;National Medical Association 《Journal of the National Medical Association》2004,96(9):1152-1161
ISSUE: Inadequate pain management is a serious public health problem that affects a wide cross-section of Americans. Patients are often denied sufficient medication, because physicians lack training and fear scrutiny from federal and state regulatory agencies. In addition, even the state-financed system of care, Medicaid, has been increasingly denying payment for the best treatment for pain management. These factors are complicated by physician bias about various subgroups and poor physician-patient communication. Comprehensive patient assessment plays a crucial role in determining appropriate treatment and identifying potential abuse problems. Physicians must routinely document medications analgesic effects and screen for potential ill effects and drug abuse. OBJECTIVE: To examine the prevalence of the undertreatment of pain, particularly among African Americans, and to recommend relevant proactive policy and practice changes to aid in eliminating this health problem. CONSENSUS PROCESS: In July 2002, the NMA convened the "Managing Pain: The Challenge in Underserved Populations: Appropriate Use versus Abuse and Diversion" Consensus Meeting in Washington, DC. The country's most renowned experts in the area of pain management and substance abuse reviewed substantial information regarding pain management and substance abuse including the following: --A draft summary paper on pain management and substance abuse that served as briefing material for consensus members; --Annotated bibliographies; --Articles on pain management and substance abuse; and --Key presentations on pain management and substance abuse. 相似文献
38.
Margaret A. MacNeil Stephen G. Lomber Bertram R. Payne 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》1997,113(1):24-32
We investigated the constancy and variability in the numbers of thalamic and cortical neurons projecting to cat middle suprasylvian
(MS) visual cortex. Retrograde pathway tracers were injected at a single anatomically and physiologically defined locus in
MS cortex. Counts of labeled neurons showed that the visual thalamic projections to MS cortex consistently arose from a fixed
set of nuclei in relatively constant proportions. In contrast, counts of cortical neurons revealed that transcortical inputs
to MS cortex were much more variable. This differential variability may be linked to the developmental program, which affords
greater influence of experiential factors on cortical pathway development than on thalamocortical pathway development. These
results have implications for the development of models of cerebral connectivity that include measures of pathway variability.
Received: 29 March 1996 / Accepted: 3 September 1996 相似文献
39.
Claire M. Payne Raymond B. Nagle Samuel H. Paplanus Anna R. Graham Martin M. Berman 《Ultrastructural pathology》1986,10(6):539-552
Immunohistochemical and ultrastructural findings in two cases of fibrolamellar carcinoma of the liver and two cases of hepatocellular carcinoma of the common histologic type are described. Ultrastructural examination of both cases of fibrolamellar carcinoma revealed the presence of neurosecretory (NS) granules which were sparse in some cells and abundant in others. Many of the tumor cells had a distinct oncocytic appearance with abundant mitochondria. A portion of the glutaraldehyde-fixed neoplasm was processed for the uranaffin reaction (an ultrastructural cytochemical stain specific for the NS granules of neuroendocrine tissue). Abundant uranaffin-positive granules were found in the neoplastic cells of both cases of fibrolamellar carcinoma, whereas no uranaffin-positive granules were found in hepatocellular carcinoma of the common histologic type. There was no statistical difference in the mean diameter of the uranaffin-positive granules measured from both cases. Immunohisto-chemistry revealed the presence of neuron-specific enolase (NSE) and serotonin in one of the two cases of fibrolamellar carcinoma and no NSE staining in two cases of hepatocellular carcinoma of the common histologic type. These findings suggest that some liver tumors presenting histologically as fibrolamellar carcinoma may be neuroendocrine in nature. 相似文献
40.
Mnemonic coding system for clinical data entry into laboratory computers: its effect on quality and efficiency. 下载免费PDF全文
I R Bailey K B Page R G Jones R B Payne A J Little 《Journal of clinical pathology》1991,44(12):1018-1021
A simplified coding method for entering the clinical details found on pathology request cards was developed. The method uses a basic four letter code, derived from the initial character of the first four words in a clinical detail, being expanded to four characters with letters from the final word if the number of words is less than four. Rules were devised to cope with common medical terminology. In excess of 90% of clinical details on request cards are readily input by clerical staff using our coding system, and 8% of clinical details are used intelligently by the computer in scheduling further tests or automatically commenting on results. A carefully designed coding system such as the one outlined above could greatly facilitate input of clinical detail without the penalty of reduced throughput. 相似文献