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ERP evidence of impaired central nervous system function in virally suppressed HIV patients on antiretroviral therapy. 总被引:2,自引:0,他引:2
Linda L Chao Joselyn A Lindgren Derek L Flenniken Michael W Weiner 《Clinical neurophysiology》2004,115(7):1583-1591
OBJECTIVE: To examine the effects of human immunodeficiency virus (HIV) on central nervous system (CNS) function in patients receiving antiretroviral therapy (ART) who have suppressed viral loads. METHODS: Event-related brain potentials (ERPs) were recorded from 15 virally suppressed HIV patients and 15 age-, sex-, and education-matched controls while they performed a 3-stimulus auditory oddball task. The amplitude and latency of the P3a, P3b, and early auditory components were examined in HIV patients and controls. RESULTS: Virally suppressed HIV patients on ART were more depressed than controls, as determined by the Beck Depression Inventory (BDI). After controlling for the effects of depression, HIV patients had smaller P2, P3a, and P3b amplitudes and longer P3a and P3b latency than control subjects. BDI scores correlated positively with N1 latency in HIV patients and negatively with P3b amplitude in all subjects. CONCLUSIONS: These electrophysiological results suggest that, even in the absence of detectable levels of HIV in the peripheral blood, viral replication persists in the CNS and continues to cause disease in HIV patients on ART. 相似文献
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The concave and convex rib-vertebral angle (RVA) at levels T2–T12 was measured on AP radiographs of 19 patients with right convex idiopathic thoracic scoliosis and 10 patients with major thoracic right convex neuromuscular scoliosis. The difference between the angles on the concave and the convex sides, the RVAD, was calculated. The RVAs were also measured on radiographs from three animal groups in which spinal curves had been induced experimentally in a variety of ways. Group 1 comprised 16 rabbits that had been subjected to selective electrostimulation of the latissimus dorsi, the erector spinae and the intercostal muscles. Group 2 comprised four dead rabbits whose spines had been subjected to manual bending. Group 3 comprised eight rabbits that had undergone mechanical elongation of one rib. In both the idiopathic and the neuromuscular group, the convex RVA was smaller than the concave RVA between levels T2 and T8, with a maximal difference between T4 to T5. From T9 to T12 the concave RVA was smaller than the convex. The RVA in relation to the scoliotic segment, i.e. the apex level of the curve and the two neighbouring vertebrae above and below this level, showed similar results. With increasing Cobb angle the RVADs increased linearly with the greatest difference at the second vertebra above the apex. In the three experimental groups the pattern of the RVADs between T6 to T12 was basically similar to the findings of the clinical study. From the results of these clinical and experimental studies, it is concluded that the typical pattern of the RVAs on the concave and convex sides seems to be independent of the underlying cause of the spinal curvature. It is likely that the RVADs result from a passive mechanical adaptation of the ribs to the lateral curvature of the spine. 相似文献
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K Daly G S Giebink P B Batalden R S Anderson C T Le B Lindgren 《The Pediatric infectious disease journal》1991,10(7):500-506
This double blind, placebo-controlled trial was designed to determine whether intervention with a stepped regimen of trimethoprim-sulfamethoxazole (TMP-SMX) and prednisone would prevent high risk children from developing chronic otitis media with effusion (OME) and recurrent acute otitis media. Forty-two children were enrolled, assigned to treatment with active drug or placebo and then examined at 2-week intervals. They received TMP-SMX (or placebo) during the first 2 weeks, TMP-SMX and prednisone (or placebo) during Weeks 3 and 4 for persistent OME and TMP-SMX (or placebo) for Weeks 5 and 6 if OME was still unresolved. After treatment 48% of active drug and 14% of placebo subjects resolved OME bilaterally (P less than 0.05). Active drug subjects also had fewer acute otitis media episodes than placebo subjects while receiving study treatment (P less than 0.01). Although this treatment regimen produced short term OME resolution, long term benefits were not demonstrated. 相似文献
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S. Lindgren S. Larsson M. Holgerssonr B. Bake 《Clinical physiology and functional imaging》1994,14(2):169-179
Summary. To investigate the ability of various lung-function tests to demonstrate dilatation of peripheral airways, ten asthmatics inhaled increasing doses of a f2-agonist by two different and controlled techniques. Low inspiratory flow with a long post-inspi-ratory pause favoured peripheral deposition, and a high inspiratory flow with a short post-inspiratory pause favoured central deposition of drug in the airways. Ordinary spirometry, maximum expiratory flow rates after breathing air as well as a helium-oxygen mixture, a single breath N2-test and resistance of the respiratory system were obtained before and after each of five terbutaline doses with both inhalation techniques. By using a double-dummy technique, the study could be performed double blinded. Effects were compared at doses giving equal effects on PEF, assumed to represent equal deposition of bronchodilator and effects on central airways. At such ‘iso A PEF doses’, particularly FVC and the slope of phase III of the N2-test improved more following the slow inhalation technique. It is concluded that changes in those tests reflect dilatation in peripheral airways in asthmatics., 相似文献
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E Reissell L Lindgren I Tikkanen J Ahonen 《Scandinavian journal of urology and nephrology》1992,26(4):403-408
Diabetic (DM) nephropathy is an indication of renal transplantation in 30% of all cases in our hospital. We assessed retrospectively the outcome of these diabetics (DM) in comparison with their non-diabetic (NDM) controls. Each diabetic (n = 24) had a control (n = 24) receiving a kidney from the same donor. There was no difference in the stage of uraemia preoperatively. Anaesthesia and fluid therapy were standardized. Peroperative hypotension occurred more often in diabetics (NS). All operating parameters including cold ischaemia were comparable. Kidney function started immediately in 14/24 in the DM group and 13/24 in the NDM group and was delayed in 10/24 and 11/24, respectively. One diabetic patient rejected the transplant as did two non-diabetic patients. Postoperatively diuretics could be discontinued more often in the DM than in the NDM group (p < 0.05). Antihypertensives had to be started in the NDM more often (NS) than in the DM group. In conclusion, the outcome of diabetic patients after renal transplantation was comparable to their NDM controls. 相似文献
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Summary The influence of mediolateral deformity, tibial torsion, and different centers of foot support was studied with a three-dimensional computer model that incorporates the significant muscles of the lower extremities needed for quasi-static walking. This theoretical method avoids the variability in gait pattern from the pain and discomfort associated with deformity in patients. The study illustrates the possible importance of the muscle force on the load across the knee and ankle. High strains in the medial gastrocnemius and the medial hamstring created particularly high loads in the medial compartment of the knee. Internal torsion and varus deformity were associated with the highest loads in the medial compartment of the knee, although the peak load for each deformity occurred in different phases of the gait cycle. Both external torsion and valgus deformity generally decreased the load in the medial compartment, but early in the gait cycle external torsion increased the loads on the medial side. In addition, when the center of support of the body was in the forefoot, the loads through the knee were lower than when foot support was at the heel. As expected, if the center of support was on the lateral foot line, the lateral compartment was subjected to more load and, conversely, when the center of support was on the medial part of the foot the medial compartment of the knee was more loaded. Although the predicted forces agree well with those found with other methods, we think that the model is best used to measure the direction of influence of specific factors. 相似文献
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Forty male New Zealand white rabbits were treated with immobilization and forcible manipulation of the right knee known to cause ectopic bone formation in the quadriceps muscle. The animals were also treated with either: A) A total radiation dose of 1840 rad (18.4 Gy); B) A 0.5 mg/kg/day oral dose of prednisolone; C) 10 mg/kg/day of indomethacin, given in two oral doses; D) Ethane-1-hydroxy-1,1-diphosphonate (EHDP) given in a 20-mg/kg/day oral dose; or E) with the vehicle given alone as a control. The experimental period was four weeks, and the amount of ectopic bone was determined by planimetry of serial transverse sections of the femur. The degree of knee stiffness was recorded during the experiment. The amount (mean +/- SEM) of ectopic bone was 1.412 +/- 0.264 cm3 in controls; it was insignificantly higher in the EHDP-treated group, but significantly lower (p less than 0.01) in rabbits treated with radiation (0.390 +/- 0.094 cm3), prednisolone (0.181 +/- 0.076 cm3), and indomethacin (0.314 +/- 0.112 cm3). In control animals and those given EHDP, the treatment invariably led to almost complete stiffness of the right knee. The rabbits treated with prednisolone and indomethacin offered the least resistance to the manipulations, and the group treated with radiation showed intermediate stiffness. Semiquantitative histologic evaluation demonstrated less inflammation in the group treated with prednisolone than in the control group. 相似文献