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11.
fMRI has been used to characterize the abnormal brain activity after stroke during attempted motor tasks, the change in brain activity accompanying spontaneous motor recovery, and response to interventions. However, many patients after stroke exhibit abnormally high effort during attempted movements, including undesired movements of the supposed quiescent, uninvolved limb, which could confound fMRI measures. We developed a method of identifying the potentially confounded scans, using EMG measures of muscle activity in the supposed quiescent limb. We found that there was no interference in the MRI signal from the EMG data acquisition system, during simultaneous use of both MRI and EMG. For EMG signal acquisition, as expected, we were able to identify EMG signal free of MRI noise contamination during the inter-scan interval between any given scan and its subsequent scan. We tested movement of the involved limb. We determined that when undesired muscle activation was present in the uninvolved, supposed quiescent limb, there was an over-estimation of the number of active voxels ranging from 10 to 11, depending upon the ROI. 相似文献
12.
Naturally occurring antibodies against the negatively charged phospholipids cardiolipin (CL) and phosphatidylserine (PS) have been associated with recurrent pregnancy loss. One prevalent hypothesis proposes that antiphospholipid antibody (aPL) mediated pathophysiology is through increased placental thrombosis. In this study we investigated the reactivity of three mouse monoclonal aPLs with term and 26 week human placental preparations. Each monoclonal antibody reacted differently with CL and PS; 3SB9b reacted with PS (CL-/PS+), D11A4 reacted with CL (CL+/PS-) and BA3B5C4 reacted with both CL and PS (CL+/PS+). 3SB9b reacted strongly with the syncytiotrophoblastic layer of both formalin fixed and frozen placental tissue. Sporadic reactivity was observed against the cytotrophoblastic layer. BA3B5C4 reacted strongly and specifically with cytotrophoblastic cells. D11A4 had only weak reactivity in the subtrophoblastic stromal region of the placenta in frozen sections. aPL staining was also observed against extravillous cytotrophoblast. BA3B5C4 stained cytoplasmic structures, whereas 3SB9b stained the plasma membrane region with little cytoplasmic staining. These data suggest that the trophoblastic layer is reactive with aPLs and may potentially be directly damaged through mechanisms unrelated to thrombosis. In addition, the trophoblastic layer directly in contact with the maternal circulation is most reactive with aPLs that are PS+ rather than CL+. The differential reactivity of 3SB9b and BA3B5C4 suggests that the antigenic conformation involving PS on the cytotrophoblast is altered concurrent with fusion into the syncytium. 相似文献
13.
W E Benitz N Malachowski R S Cohen D K Stevenson R L Ariagno P Sunshine 《The Journal of pediatrics》1985,106(1):102-110
Sodium nitroprusside was administered to 58 neonates, including 11 with severe respiratory distress syndrome, 15 with persistent pulmonary hypertension of the newborn, 28 with clinical shock, three with systemic hypertension, and two with pulmonary hypoplasia, all refractory to conventional intensive therapy. Nitroprusside was infused at 0.2 to 6.0 micrograms/kg/min for periods of 10 minutes to 126 hours. Infants with severe respiratory distress syndrome had increased PaO2 and decreased PaCO2 or peak inspiratory pressure, and nearly all (82%) survived. Infants with persistent pulmonary hypertension of the newborn had variable responses; improvement did not correlate with survival, but survival (47%) was identical to that in an earlier series of infants given tolazoline. Infants in shock had improved perfusion, urine output, and serum bicarbonate levels, and these responses were significantly related to survival. Hypertension was controlled in all three hypertensive infants. Adverse effects were very uncommon. Toxic effects were not observed. Sodium nitroprusside is effective and can be used safely in circulatory disorders in the neonate. 相似文献
14.
IgG and IgM have been identified on the surface of maternal platelets in both autoimmune thrombocytopenia (ATP) and pregnancy-induced hypertension (PIH). IgG is also found on the umbilical cord platelets of patients with ATP and PIH, whereas IgM is only found on the umbilical cord platelets of patients with PIH. The possible maternal or fetal origins of these umbilical cord blood immunoglobulins were investigated by immunoblot analysis of antibodies in paired maternal and umbilical cord blood sera of ATP and PIH patients. Maternal sera contained IgG and IgM antibodies which reacted with several platelet proteins, however, a large amount of patient-to-patient variation was observed in the specific antigens that were identified. Analysis of paired maternal and umbilical cord sera from patients with ATP or PIH showed identical patterns of antigen specificity, which suggested that the IgG antibodies in the fetal circulation were of maternal origin. Circulating IgM antibodies were not observed in the umbilical cord sera of ATP patients. The umbilical cord sera of PIH patients, however, contained IgM antibodies that reacted against a variety of platelet antigens. In addition, most umbilical cord sera from PIH patients had identical patterns and relative intensities of reactivity, which differed from the patterns observed in the paired maternal sera. Antiplatelet IgM in the umbilical cord blood of PIH patients, therefore, appears to be a product of the fetal immune system. 相似文献
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Radiology at the turn of the millennium 总被引:4,自引:0,他引:4
Herein, the authors (a) review the status of the specialty; (b) report and analyze the various areas in which progress has occurred, namely, conventional radiology and picture archiving and communication systems (or PACS), ultrasonography, computed tomography, magnetic resonance imaging, interventional radiology, and nuclear medicine; and (c) discuss the problems radiology faces as it enters the new millennium. The problems are those facing medicine as a whole, as well as those threatening the future of radiology. These include the following: Will there be a need for radiologists in the future? Will radiology be too costly to be affordable? How can turf wars and fragmentation be solved? Possible remedies are suggested. Positive aspects are discussed in the light of the challenge to demonstrate value. Medical imaging is entering the new millennium with a solid record of recent advances in digital, cross-sectional, and interventional radiology. These advances have made the specialty indispensable in the treatment of patients. Careful statesmanship will be needed to solve the many problems that face medicine as a whole and radiology in particular. 相似文献
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R L Brunelle R E George A Sunshine W D Hammonds 《Clinical pharmacology and therapeutics》1988,43(6):663-667
A double-blind, parallel study was conducted to evaluate the analgesic effect and safety of a single 25 mg oral dose of picenadol, a centrally acting analgesic, and to compare it with a 60 mg dose of codeine and a placebo in patients with postoperative pain. Two sites using similar protocols enrolled a total of 178 inpatients with postoperative pain. Pain intensity, relief, and adverse experiences were then measured for up to 6 hours after administration of the test medications. Both picenadol and codeine were significantly more effective than placebo in reducing pain intensity (mean sum of pain intensity difference scores: picenadol 5.21, codeine 5.19, and placebo 2.82) and increasing total relief (mean total pain relief: picenadol 10.21, codeine 11.07, and placebo 6.96). Adverse experience profiles were similar among the three treatment groups. 相似文献
20.
P2 phage amber mutants: characterization by use of a polarity suppressor 总被引:35,自引:0,他引:35