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61.
Background contextChronic back pain is a condition characterized by high rates of disability, health-care service use, and costs.PurposeThe purpose of this study was to identify factors associated with patients' satisfaction with their last health-care provider visit for chronic low back pain (LBP).Study design/settingA cross-sectional, state-level, telephone survey was administered to patients with chronic LBP.Patient sampleThe sample consisted of 624 individuals with chronic LBP who reported seeing a health-care provider in the previous year.Outcome measuresDependent variables included satisfaction with last visit for LBP and intent to seek care from additional providers. Independent variables included the Roland-Morris Disability Questionnaire, 3-month pain ratings using a 0 to 10 Likert scale, the Medical Outcomes Survey Short Form 12, and self-reported health service utilization (provider type, number of visits to health-care providers, medication use during the previous month, and treatments and diagnostic tests during the previous year).MethodsBivariate and multivariate analyses were used to explore how demographic, insurance-related, and health-related characteristics were associated with patient satisfaction.ResultsParticipants who were not satisfied with one or more aspects of their last clinic visit were younger (51.0 vs. 54.21 years), reported higher 3-month pain ratings (7.23 vs. 6.53), and were more commonly Hispanic (53.2% vs. 46.8% for other ethnicities) and uninsured (43.1% vs. 29.3% for other insurance groups). Those who intended to seek care from additional providers were younger (50.05 vs. 55.49 years), had higher 3-month pain ratings (7.20 vs. 6.46), had lower Short Form 12 mental health component scores (44.75 vs. 49.55) and physical component scores (30.07 vs. 31.55), and were more commonly black (54.6% vs. 45.4% for other racial groups) and uninsured (56.9% vs. 43.1% for other insurance groups). Narcotic use was associated with satisfaction (odds ratio=2.12, p=.01), whereas lack of insurance was associated with respondents' intent to seek care from additional providers (odds ratio=2.97, p<.01).ConclusionsFactors other than disability were associated with satisfaction with chronic LBP visits. Understanding the role of medication in satisfaction and its implications for the health behaviors of this highly disabled population may be particularly important.  相似文献   
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Introduction . The mechanism(s) whereby atrial ectopy induces atrial fibrillation (AF) is still poorly understood.
Methods and Results . In 12 dogs, we determined the refractory period (RP) along the right atrium (RA) and right superior pulmonary vein (RSPV), and AF inducibility with and without concurrent stimulation of the anterior right ganglionated plexi (ARGP) at the base of the RSPV. Multielectrode catheters were attached to the RSPV and RA with the distal electrodes close to ARGP. The RP and window of vulnerability (WOV), i.e., the longest S1–S2 minus the shortest S1–S2 at which AF was induced, were measured before and during incremental levels of ARGP stimulation. Mapping of the onset of AF was performed using the EnSite® mapping system (St. Jude Medical, St. Paul, MN, USA) positioned in the RA.
A single premature depolarization (PD) from the RSPV that did not induce AF without ARGP stimulation could do so with ARGP stimulation. The onset of AF consistently arose at the myocardium subtending the ARGP. With GP stimulation, the average WOV at the RSPV-atrial junction was significantly wider than at the RA appendage (65 ± 27 vs. 8 ± 17 msec, P < 0.05) or further along the RSPV sleeve (48 ± 39 vs. 10 ± 20 msec, P < 0.05). Even without GP stimulation, high intensity (10–20 mA) premature stimuli delivered at the RA appendage induced AF, originating from atrial tissue subtending the ARGP, presumably due to axonal conduction that activated the ARGP.
Conclusion . GP stimulation, subthreshold for atrial excitation, converts isolated PDs into AF-inducing PDs, suggesting that autonomic tone may play a critical role in the initiation of paroxysmal AF.  相似文献   
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Expression of the E6 oncoprotein of human papillomavirus (HPV) 16 in primary human keratinocytes (PHKs) was previously shown to significantly reduce apoptosis. This could be due to increased cell adhesion. Adhesion ability was tested by seeding cells on tissue culture dishes coated with different concentrations of poly(HEME) and determination of the proportion of attached cells. Assays were carried out with PHKs, immortalized human keratinocytes (HaCaT) and human 293T cells. The E6 gene was transduced via retroviral infection or DNA transfection. Results of these assays showed that expression of E6 increased the proportion of cells that attached to poly(HEME). Several HPV16 E6 mutants were also tested in the above assay in 293T cells. These assays showed that the p53 targeting region of E6 is dispensable for this activity. Assays of inhibition of tyrosine kinases by bombesin showed that E6 probably utilizes other pathways to increase cell adhesion.  相似文献   
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Sandwich ELISAs have been produced to detect ruminant and porcine heat stable proteins which have been heated to 130°C, 2.7 bar (absolute pressure), for 30 mins and incorporated into compound animal feedstuffs (CAFs). Sample preparation involves heat treatment, removal of CAF proteins and analyte concentration. The test system incorporates a separate ELISA to detect non-specific binding of certain plant derived CAF components, each of which are identified. Both ruminant and porcine heat stable antigens are detected at a concentration of 1250 ppm. %CVs obtained within assay were 6.97% and between assay 9.07%. The maximum calculated false negative rate over 3 years of routine operation of the ELISAs was <1%. Each assay plate incorporates 12 negative controls permitting an additional 3SD calculation to overcome any in-plate variation.  相似文献   
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Catheter recordings of accessory pathway (AP) activation were used to identify the site of antegrade and retrograde AP conduction block in 126 consecutive patients undergoing electrophysiological testing. Activation was recorded from 89 of 121 left free-wall and posteroseptal pathways (left APs) and from 12 of 24 right free-wall, midseptal, and anteroseptal pathways (right APs). The recorded APs were further subdivided into those exhibiting consistent antegrade conduction during sinus rhythm (overt APs: 50 left APs, eight right APs), those exhibiting intermittent antegrade conduction (intermittent APs: six left APs, two right APs), and those exhibiting only retrograde conduction (concealed APs: 33 left APs, two right APs). The sites of block were recorded during decremental atrial and ventricular stimulation. The sites of both antegrade and retrograde block were determined in 40 of 50 overt left APs and six of eight overt right APs. Antegrade and retrograde block occurred at or near the AP-ventricular (AP-V) interface in 37 of 40 overt left APs and two of six overt right APs and at the atrial-AP (A-AP) interface in one of 40 overt left APs and four of six overt right APs. In three of three overt left APs with no retrograde conduction, retrograde block occurred at or near the AP-V interface. The site of antegrade and retrograde block differed in only two of 58 overt pathways. There was no difference between overt APs limited at the A-AP or the AP-V interface in the shortest atrial or ventricular pacing cycle length maintaining 1:1 antegrade or retrograde AP conduction, respectively. Both antegrade and retrograde block occurred near the AP-V interface in four of six intermittent left APs and zero of two intermittent right APs and near the A-AP interface in two of six intermittent left APs and one of two intermittent right APs. The sites of both antegrade and retrograde block were determined in 28 of 33 concealed left APs, and both occurred at or near the AP-V interface in 26 and A-AP interface in two APs. In two of two concealed right APs, antegrade block occurred at the AP-V interface. These findings suggest that both antegrade and retrograde conduction are limited by factors operating near the AP-V interface in overt left APs and at the A-AP or AP-V interface in overt right APs. Factors limiting antegrade conduction in concealed APs appear to be located almost always near the AP-V interface.  相似文献   
70.
Results of surgical treatment of neonatal necrotizing enterocolitis.   总被引:1,自引:0,他引:1  
In 6 years, 74 neonates were treated for necrotizing enterocolitis, 40 (54 per cent) of whom underwent operation. The early postoperative mortality rate was 23 per cent and there was one late death. Of the 30 postoperative survivors, two have short bowel syndrome, two have chronic respiratory disease, two are partially sighted, and five (17 per cent) have severe developmental delay. Only 15 (50 per cent) survivors enjoy good health.  相似文献   
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