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101.
Peter A. Shapiro Richard P. Sloan Emilia Bagiella J. Thomas Bigger JR. Jack M. Gorman 《Psychophysiology》1996,33(1):54-62
Heart rate reactivity to mental stress is substantially blunted early after heart transplantation, suggesting that the loss of neural modulation limits the cardiovascular response to mental stress. We tested whether reactivity to mental stress recovers during the first year after heart transplantation. Hemodynamic and respiratory responses to mental arithmetic challenge were studied in 20 heart transplant recipients 3, 6, and 12 months after surgery. A normal comparison group was studied at equivalent intervals. Heart rate reactivity to mental arithmetic was significantly reduced in the cardiac transplant group compared to the normal subjects. This effect persisted up to 1 year after transplantation. Heart period variability in the heart transplant recipients was minimal in all three-test sessions. The findings suggest that no functional reinnervation or other compensatory adaptation occurs up to 1 year after heart transplantation. 相似文献
102.
IgG antibody to gE, the Fc gamma-binding herpes simplex 1 (HSV-1) viral glycoprotein, was studied in 49 rheumatoid arthritis (RA) patients and 43 normal controls. Antibody to gD, another important HSV-1 antigen, was assayed in parallel. No difference between RA patients and normal controls was found in levels of anti-gE antibody measured by reactivity of IgG F(ab')2 fragments reacting with gE coated to ELISA plates. No difference in anti-gD antibody was recorded between normals and patients with RA. Levels of IgG anti-IgE antibody did not correlate with quantitative elevations of serum rheumatoid factor (RF) in RA patients. When IgG anti-gE and anti-gD were assayed in 20 patients with juvenile rheumatoid arthritis and 22 children controls, no significant differences were noted. However, when individual RFs from patients with RA were tested for reactivity against a panel of affinity-isolated F(ab')2 antibodies to gE, some evidence for individual autospecificity was obtained. Four of 20 monoclonal IgM RFs produced from RA patients' B cells showed marked elevations of reactivity with some RA patients' F(ab')2 antibodies to gE. All four of the monoclonal RFs showing this specificity were derived from RA synovial tissue B cells. These findings may provide support for the concept that some RFs in patients with RA show individual specificity for internal image determinants of IgG antibodies to viral Fc gamma-binding proteins. 相似文献
103.
104.
105.
Maxwell DJ Kerr R Rashid S Anderson E 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》2003,149(1):114-124
Serotonin 5-HT3 receptors are abundant in the superficial dorsal horn and are likely to have an involvement in processing of nociceptive
information. It has been shown previously that 5-HT3 receptors are present on primary afferent terminals and some dorsal horn cells. The primary aim of the present study was
to determine what classes of primary afferent possess 5-HT3A receptor subunits. We performed a series of double- and triple-labelling immunofluorescence experiments. Subunits were labelled
with an anti-peptide antibody and primary afferent axons were identified by the presence of calcitonin gene-related peptide
(CGRP) and binding of the lectin IB4. Quantitative confocal microscopic analysis revealed that approximately 10% of axons
displaying 5-HT3A immunoreactivity were also labelled for CGRP but that only 3% of these fibres bind IB4. We also investigated the relationship
between immunoreactivity for the subunit and descending serotoninergic systems, axons originating from inhibitory neurons
that contain glutamic acid decarboxylase, and axons of a subpopulation of excitatory neurons that contain neurotensin. None
of these types of axon was associated with immunoreactivity for receptor subunits. Ultrastructural studies confirmed that
punctate immunoreactive structures observed with the light microscope were axon terminals. These terminals invariably formed
asymmetric synaptic junctions with dendritic profiles and often contained a mixture of granular and agranular vesicles. Some
terminals formed glomerular-like arrangements. Immunoreactive cells were also examined and were found to contain intense patches
of reaction product within the cytoplasm. We conclude that the majority (about 87%) of dorsal horn axons that are immunoreactive
for 5-HT3A receptor subunits do not originate from the subtypes of primary afferent fibres that bind IB4 or contain CGRP. It is likely
that most of these axons have an excitatory action and they may originate from dorsal horn interneurons and/or fine myelinated
primary afferent fibres.
Electronic Publication 相似文献
106.
Catt SL; Sakkas D; Bizzaro D; Bianchi PG; Maxwell WM; Evans G 《Molecular human reproduction》1997,3(9):821-825
Controlling the sex of offspring by the separation of X and Y
chromosome-bearing spermatozoa using flow cytometry has been reported as a
clinical technique aiding prevention of X-linked diseases. Although this
technique has resulted in several hundred normal births in animals and at
least one human birth, there is still concern over its genetic safety due
to the involvement of two potentially mutagenic agents: UV light and the
fluorochrome dye, Hoechst 33342 (H33342). Human spermatozoa, particularly
those considered abnormal, may be more likely to suffer DNA damage
following exposure to mutagenic agents, compared with other mammalian
species. The stability of normal fresh and decondensed human spermatozoa
were examined after exposure to a range of levels of UV and H33342
staining, using an assay that detects endogenous nicks in the DNA of
spermatozoa. The stability of abnormal and normal, fresh and frozen-thawed
human spermatozoa was examined following UV laser, H33342 staining and flow
cytometry treatments utilizing the same assay. There was an increase in the
presence of endogenous nicks when spermatozoa were decondensed compared
with fresh spermatozoa. There was no increase in the incidence of nicks in
any group of spermatozoa after UV and fluorochrome exposure compared with
controls without exposure.
相似文献
107.
108.
Brass DM Savov JD Whitehead GS Maxwell AB Schwartz DA 《The Journal of allergy and clinical immunology》2004,114(3):586-592
BACKGROUND: Inhaled endotoxin is a risk factor for asthma exacerbation, and endotoxin inhalation by itself recapitulates many of the classical features of asthma in mice, including reversible airflow obstruction and inflammation, airways hyperresponsiveness, and airway remodeling. OBJECTIVE: Our objective was to determine the importance of LPS binding protein (LBP) in the response to inhaled LPS. METHODS: We challenged LBP-deficient mice (C57BL/6(LBP-/-)) and C57BL/6 mice with inhaled endotoxin for 4 hours, 5 days, or 4 weeks, followed by 3 days of recovery. RESULTS: LBP in the lung was significantly increased in LPS-exposed C57BL/6 mice from all 3 groups. Only LPS-exposed C57BL/6 mice had significantly enhanced airway responsiveness to inhaled methacholine. Total lavage cells in LPS-exposed C57BL/6(LBP-/-) mice were significantly reduced compared with those seen in LPS-exposed C57BL/6 mice; however, the percentage of PMNs was similarly increased in both the C57BL/6 and C57BL/6(LBP-/-) mice. TNF-alpha, IL-1 beta, and IL-6 protein concentrations in whole-lung lavage fluid from C57BL/6(LBP-/-) mice were also significantly reduced when compared with those seen in C57BL/6 mice. In C57BL/6(LBP-/-) mice submucosal cell proliferation was significantly reduced in the 1-week group when compared with that seen in similarly exposed C57BL/6 mice. The 4-week exposed C57BL/6 mice had significantly thickened airway submucosa and significantly increased lavaged TGF-beta(1) protein compared with that seen in C57BL/6(LBP-/-) mice. CONCLUSIONS: These findings indicate that LBP is one of the critical molecules regulating the acute and chronic airway response to inhaled LPS. 相似文献
109.
SPARGO P. M.; TAIT A. R.; KNIGNT P.R.; KLING T. F. JR 《British journal of anaesthesia》1987,59(5):640-647
Twenty-four mongrel dogs were anaesthetized with pentobarbitoneand morphine sulphate. Neuromuscular blockade was achieved usingpancuronium. Spinal cord blood flow was measured using the radionuclidemicrosphere and hydrogen washout methods before, during, andfollowing nitroglycerine-induced hypotension. Heart rate, meanarterial pressure, cardiac output, pulmonary capillary wedgepressure, and acid-base balance were determined with each measurement.Mean arterial pressure was reduced by 50%. Spinal cord bloodflow, as measured by the microsphere method, increased duringthe period of hypotension, whereas values obtained using thehydrogen washout method were not significantly different fromthose at normotension. No significant change in spinal cordblood flow was detected by either method after the applicationof spinal distraction. Nitroglycerine acts predominantly onvenous capacitance vessels and it is postulated that perfusionpressure, and therefore flow, is maintained despite a reductionin arterial pressure.
Presented in part at the Anual Meeting of the American Societyof Anesthesiologists, October 1985, San Francisco, California.
*Shackleton Department of Anaesthetics, Southampton GeneralHospital, Shirley, Southampton, Hants SO9 4XY.
Section of Orthopedic Surgery, Madison, Wisconsin. 相似文献
110.
DAVID R. HOLMES JR. DAVID L. HAYES JOEL E. GRAY JOHN MERIDETH 《Pacing and clinical electrophysiology : PACE》1986,9(3):360-370
The effects of magnetic resonance imaging were assessed on four dual chamber and two single chamber pulse generators. The tests were performed with a resistive, water-cooled magnet operating at 0.15 T. The 6.4-MHz radiofrequency (RF) field was operated at a maximum power of 1,000 watts with a period adjusted from 130 to 500 ms. Reed switch closure occurred in all six pulse generators tested when placed near the entrance of the magnetic resonance imaging scanner, and the generators reverted to asynchronous operation unless programmed to the "magnet off" mode. None of the pulse generators exhibited any alterations in programmed parameters or in the ability to be reprogrammed after RF pulsing. When the RF field was turned on, there was no change in the asynchronous paced cycle length in four pulse generators; however, during RF scanning there was rapid cardiac stimulation at the RF pulse period in one single chamber and one dual chamber pulse generator. 相似文献