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81.
Nancy L. Keating MD MPH Mary Beth Landrum PhD Selwyn O. Rogers Jr MD MPH Susan K. Baum MSW Beth A. Virnig PhD MPH Haiden A. Huskamp PhD Craig C. Earle MD MSc Katherine L. Kahn MD 《Cancer》2010,116(4):998-1006
BACKGROUND:
Guidelines recommend advanced care planning for terminally ill patients with <1 year to live. Few data are available regarding when physicians and their terminally ill patients typically discuss end‐of‐life issues.METHODS:
A national survey was conducted of physicians caring for cancer patients about timing of discussions regarding prognosis, do not resuscitate (DNR) status, hospice, and preferred site of death with their terminally ill patients. Logistic regression was used to identify physician and practice characteristics associated with earlier discussions.RESULTS:
Among 4074 respondents, 65% would discuss prognosis “now” (defined as patient has 4 months to 6 months to live, asymptomatic). Fewer would discuss DNR status (44%), hospice (26%), or preferred site of death (21%) immediately, with most physicians waiting for patient symptoms or until there are no more treatments to offer. In multivariate analyses, younger physicians more often discussed prognosis, DNR status, hospice, and site of death “now” (all P < .05). Surgeons and oncologists were more likely than noncancer specialists to discuss prognosis “now” (P = .008), but noncancer specialists were more likely than cancer specialists to discuss DNR status, hospice, and preferred site of death “now” (all P < .001).CONCLUSIONS:
Most physicians report they would not discuss end‐of‐life options with terminally ill patients who are feeling well, instead waiting for symptoms or until there are no more treatments to offer. More research is needed to understand physicians' reasons for timing of discussions and how their propensity to aggressively treat metastatic disease influences timing, as well as how the timing of discussions influences patient and family experiences at the end of life. Cancer 2010. © 2010 American Cancer Society. 相似文献82.
The mammalian superior cervical ganglion (SCG) contains a complex mixture of neuronal phenotypes that selectively innervate different peripheral targets. The present study examined the rostro-caudal topography of sympathetic phenotypes in the rat SCG by analyzing the relation between cell position, size, and the expression of immunoreactivity for neuropeptide Y (NPY), calretinin, and calcitonin gene-related peptide (CGRP). We observed that 64% of SCG neurons expressed NPY and had an average diameter of approximately 24 microm throughout the ganglion. Previous studies indicate that most of these cells are vasoconstrictor in function. By contrast, the size of NPY-negative neurons varied from approximately 25 microm in the rostral ganglion near the internal carotid nerve to approximately 30 microm in the caudal ganglion between the external carotid nerve and cervical sympathetic trunk. Many of the large NPY-negative neurons in the caudal ganglion were surrounded by dense axonal baskets that were immunoreactive for calretinin and therefore are likely to be secretomotor neurons projecting to salivary glands. Consistent with earlier reports, the rostral ganglion contained low numbers of presumptive pupillomotor neurons, based on their expression of NPY and contact with fibers containing CGRP. The present results indicate that neuronal size may provide a useful aid to cellular identification, especially in the caudal ganglion, and they provide further evidence of a topographic organization within the mammalian SCG. 相似文献
83.
Enkephalins and dorsal horn neurones of the cat: effects on responses to noxious and innocuous skin stimuli. 总被引:2,自引:6,他引:2
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1. In spinal cats anaesthetized with alpha-chloralose, a study was made of the effects of methionine enkephalin and methionine enkephalin amide on the responses of neurones of spinal laminae IV and V to noxious and innocuous skin stimuli. The enkephalins were ejected from micropipettes either in the region of cell bodies or in the substantia gelatinosa. 2. Administered near cell bodies the enkephalins reduced spontaneous firing and cell responses to both types of skin stimuli. These effects were antagonized by naloxone when administered near cell bodies but not when given intravenously in doses (0.3-0.6 mg/kg) more than adequate to antagonize analgesic doses of morphine. 3. Administered in the substantia gelatinosa the enkephalins were more selective in their action. The predominant effect was a reduction in nociceptive responses with little effect on non-nociceptive responses although spontaneous firing was commonly reduced. Naloxone administered either in the substantia gelatinosa or intravenously (0.1-0.3 mg/kg) reversed these effects of the enkephalins. 相似文献
84.
Experimental have been performed on Renshaw cells of rats to investigate the receptors mediating both the responses to electrophoretically applied cholinergic excitants and the synaptic excitation following stimulation of the ventral roots. The effects of atropine and dihydro-β-erythroidine, muscarinic and nicotinic antagonist respectively, have been tested on both types of excitation. Most important we found that in the rat the ventral root evoked response can be blocked by atropine as well as by DHβE. It was not possible to categorise the responses to the cholinergic agents in terms of muscarinic and nicotine receptors. In addition we have failed to find the late (muscarinic) excitation seen in the cat. 相似文献
85.
The antibacterial activity of cefpirome (HR810), a new cephalosporin, was compared with that of other "third-generation" cephalosporins, as well as cefuroxime, piperacillin and gentamicin. Cefpirome was the most active beta-lactam antibiotic against Gram-negative bacteria. The MIC90 for Enterobacteriaceae was always less than 0.5 ml/l except for Enterobacter species. The MIC90 against Pseudomonas species was 2 mg/l, which was equal to that of ceftazidime and gentamicin. Cefpirome was also more active than the other beta-lactam antibiotics against Staphylococcus aureus. A relatively high frequency of synergy was observed when cefpirome was combined with aminoglycosides against both Gram-positive and Gram-negative bacteria. No antagonism was detected. This antibiotic was very stable to both plasmid- and chromosomally-mediated beta-lactamases. It was more resistant to Enterobacter cloacae P99 enzyme than ceftazidime, cefotaxime and cefotetan. Its stability to the Klebsiella K1 beta-lactamase was more than that of cefotaxime and ceftriaxone but slightly less than that of ceftazidime and latamoxef. MBC90 values for cefpirome were generally less than twice the corresponding MIC values. 相似文献
86.
The effect of morphine and naloxone on basal and forskolin-stimulated efflux of cyclic AMP from rat striatal slices was examined. Neither morphine nor naloxone had any consistent effect on the basal efflux of cyclic AMP. Forskolin produced a time and dose-dependent enhancement of cyclic AMP efflux. Neither morphine nor naloxone affected this forskolin-enhanced release. These results suggest that measurements of cyclic AMP released from brain slices do not accurately reflect effects on adenylate cyclase inhibition by opiates. 相似文献
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90.
The pathological findings in a 13-year-old dog with cutaneous myxosarcoma with pulmonary metastases are described. Grossly, there was a large subcutaneous mass in the right scapular region, a smaller nodule in the caudal abdominal region and a fibrotic mass at a fracture site in the right hindlimb. Radiographic examination revealed several pulmonary nodules. Microscopical evaluation revealed a myxosarcoma characterized by the proliferation of spindle to stellate cells with multiple prominent nucleoli and vascular invasion. The neoplastic cells were haphazardly arranged in a mucopolysaccharide matrix. Immunohistochemically, the neoplastic cells expressed vimentin, but not cytokeratin or glial fibrillary acidic protein. There was restricted expression of desmin, smooth muscle actin and S-100 protein. 相似文献