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61.
Activation of the medial olivocochlear reflex (MOCR) can be assessed indirectly using transient-evoked otoacoustic emissions (TEOAEs). The change in TEOAE amplitudes when the MOCR is activated (medial olivocochlear (MOC) shift) has most often been quantified as the mean value in groups of subjects. The usefulness of MOC shift measurements may be increased by the ability to quantify significant shifts in individuals. This study used statistical resampling to quantify significant MOC shifts in 16 subjects. TEOAEs were obtained using transient stimuli containing energy from 1 to 10 kHz. A nonlinear paradigm was used to extract TEOAEs. Transient stimuli were presented at 30 dB sensation level (SL) with suppressor stimuli presented 12 dB higher. Contralateral white noise, used to activate the MOCR, was presented at 30 dB SL and was interleaved on and off in 30-s intervals during a 7-min recording period. Confounding factors of middle ear muscle reflex and slow amplitude drifts were accounted for. TEOAEs were analyzed in 11 1/3-octave frequency bands. The statistical significance of each individual MOC shift was determined using a bootstrap procedure. The minimum detectable MOC shifts ranged from 0.10 to 3.25 dB and were highly dependent on signal-to-noise ratio at each frequency. Subjects exhibited a wide range of magnitudes of significant MOC shifts in the 1.0–3.2-kHz region (median?=?1.94 dB, range?=?0.34–6.51 dB). There was considerable overlap between the magnitudes of significant and nonsignificant shifts. While most subjects had significant MOC shifts in one or more frequency bands below 4 kHz, few had significant shifts in all of these bands. Above 4 kHz, few significant shifts were seen, but this may have been due to lower signal-to-noise ratios. The specific frequency bands containing significant shifts were variable across individuals. Further work is needed to determine the clinical usefulness of examining MOC shifts in individuals.  相似文献   
62.
Objective. To evaluate the psychometric properties (criterion validity, construct validity, sensitivity, and specificity) of a single-item question screening for dental anxiety in a Finnish adult population. Material and methods. A total of 823 subjects, ranging in age from 18 to 87 years, answered a questionnaire comprising sections assessing the respondents’ demographic profile and dental attendance patterns. A single dental anxiety question and the Modified Dental Anxiety Scale (MDAS) were included. The final response rate was 85%. Results. Eight percent of the sample was highly dentally anxious using the MDAS cut-off point of 19 or above. Twelve percent of the respondents rated themselves as “very scared” on the single-item question. The percentage agreement between the single-item question and the MDAS was 93; the Kappa coefficient was 0.63. Specificity of the single question was 0.95 while sensitivity was 0.80 using the MDAS dichotomous classification. The single-item question related to age (p<0.001), gender (p<0.001), and dental attendance (p<0.001), as predicted. Conclusions. The single question has good validity, specificity, and sensitivity and may be used with confidence to assess dental fear in such situations as national health surveys or in routine dental practice where a multi-item dental anxiety questionnaire is not feasible.  相似文献   
63.
Abstract

Aim: This study aimed to investigate the cultural adaptation and psychometric properties of the Persian version of self-efficacy and coping skill scales (CSE) which are relevant to substance use in Iranian adolescents. Method: The method included a forward–backward translation with face and content validity in the first step and the psychometric properties were evaluated in the second step. The study used reliability and construct validity in a cross-sectional survey, in three steps, including: item analysis, explanatory and confirmatory factor analyses in 720 adolescents, aged from 14 to 18 years old in Isfahan. Findings: In the first step, three items were excluded because of low CVI and one item was deleted due to low CITC. EFA in the cross-sectional study showed appropriate loading items and revealed an 18-item scale with four factors including: refusal self-efficacy, decision making, assertiveness and communication skills. Results of the confirmatory factor analysis represented an acceptable fitness (CMIN/DF?=?3.6, NFI?=?0.90, TLI?=?0.92, CFI?=?0.93, PNFI?=?0.76, RMSEA?=?0.06). Internal consistency was found from 0.68 to 0.89 for the four subscales. Conclusion: Overall, the results of these studies indicate that the Persian version of coping and self-efficacy appears to be a psychometrically robust instrument and could significantly predict substance use behaviour in Iranian adolescents.  相似文献   
64.
The aim of this study was to determine the effects of main factors and interactions on the color removal performance from dye solutions using the electrocoagulation process enhanced by adsorption on Granular Activated Carbon (GAC). In this study, a mathematical approach was conducted using a two-level fractional factorial design (FFD) for a given dye solution. Three textile dyes: Acid Blue 74, Basic Red 1, and Reactive Black 5 were used. Experimental factors used and their respective levels were: current density (2.73 or 27.32 A/m2), initial pH of aqueous dye solution (3 or 9), electrocoagulation time (20 or 180 min), GAC dose (0.1 or 0.5 g/L), support electrolyte (2 or 50 mM), initial dye concentration (0.05 or 0.25 g/L) and current type (Direct Current—DC or Alternative Pulsed Current—APC). GAC-enhanced electrocoagulation performance was analyzed statistically in terms of removal efficiency, electrical energy, and electrode material consumptions, using modeling polynomial equations. The statistical significance of GAC dose level on the performance of GAC enhanced electrocoagulation and the experimental conditions that favor the process operation of electrocoagulation in APC regime were determined. The local optimal experimental conditions were established using a multi-objective desirability function method.  相似文献   
65.
Abstract

Clients with cognitive impairment following acquired brain injury (CIABI) are a common group to receive occupational therapy services. Research has shown that occupational therapy has a positive effect on occupational performance for these clients, but the exact nature of the interventions is not clearly described and needs to be better understood and defined. The aim of this study was to develop and evaluate an empirically derived questionnaire for the purpose of surveying occupational therapists' (OTs') practice patterns in relation to CIABI. The questionnaire was developed from the results of a former qualitative study. It was evaluated for content validity by a group of six OT researchers with experience in CIABI, using the content validity index (CVI). Reliability was evaluated by a test–retest design with a group of 51 OTs. Data were analysed by non-parametric statistical methods. Initially the questionnaire consisted of 90 items dealing with OT practice and nine demographic questions. After the reliability and content validity process the OT practice items were reduced to 44. The revised questionnaire will be used to survey and explicitly describe occupational therapy practice for clients with CIABI.  相似文献   
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68.
Aim: To examine the utility of the Cornell scale for depression in dementia (CSDD), following its introduction as a routine measure in nursing homes. Methods: The CSDD is administered in Australian nursing homes as section 10 of the Aged Care Funding Instrument. CSDD, cognitive and behavioural ratings, and medication use, recorded in three Sydney nursing homes in 2008–2009 were reviewed. Staff discussed what actions were taken if CSDD scores indicated depression. Results: Of 223 residents, 23% scored >12 on the CSDD, indicating probable depression. Another 21% were possibly depressed and 29% not depressed. The CSDD had not been completed for 27%, commonly because preliminary screening indicated no depression, but sometimes because severe cognitive impairment made various CSDD items impossible to rate. Second CSDD assessments had usually not been made. Conclusion: Nursing homes need to document policies that will ensure best use is made of CSDD findings.  相似文献   
69.
Spence Children's Anxiety Scale (SCAS) is one of the most commonly used self-report questionnaires to measure symptoms of anxiety disorders in adolescents. Despite its common use, studies that examine the psychometric properties of SCAS in Pakistan is lacking. Therefore, the purpose of this study was to examine the psychometric properties of the Urdu translated version of the SCAS among adolescents in Pakistan. A total of 1277 students (708 boys and 569 girls), aged 13 to17 years, who had been recruited from 13 schools in Rawalpindi, Pakistan participated in the study. The mean overall anxiety score was significantly higher in girls than males on all the SCAS subscales except for obsessive compulsive disorder. The internal consistency of the Urdu SCAS was good. Confirmatory factor analyses supported six separate factor structures. Results of the study are discussed with reference to the sociocultural milieu of Pakistan and culture sensitive conceptualization of anxiety and its subtypes.  相似文献   
70.
The present study examined the construct validity and reliability of a new dribbling agility test (DAT) that incorporates reactive agility and multiple change of direction. To check its’ validity, (a) DAT was performed by four groups (under 10, under 12, under 14 and under 16 yrs) of young soccer players (n = 125 in each group) and (b) a regression analysis was conducted to define the best DAT predictors. The reliability of DAT was assessed with repeated measurements. This test can differentiate the dribbling skill between groups (p < 0.01). Furthermore, 68% of the observed variance in DAT was explained by zigzag dribbling test, Illinois agility test, reaction time and running speed. The test-retest reliability was high in all groups (ICC = 0.77 – 0.90, p < 0.01). It was concluded that DAT can be a potential tool to evaluate the dribbling performance in young soccer players.  相似文献   
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