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61.
Spatial memory enhances an organism’s navigational ability. Memory typically resides within the brain, but what if an organism has no brain? We show that the brainless slime mold Physarum polycephalum constructs a form of spatial memory by avoiding areas it has previously explored. This mechanism allows the slime mold to solve the U-shaped trap problem—a classic test of autonomous navigational ability commonly used in robotics—requiring the slime mold to reach a chemoattractive goal behind a U-shaped barrier. Drawn into the trap, the organism must rely on other methods than gradient-following to escape and reach the goal. Our data show that spatial memory enhances the organism’s ability to navigate in complex environments. We provide a unique demonstration of a spatial memory system in a nonneuronal organism, supporting the theory that an externalized spatial memory may be the functional precursor to the internal memory of higher organisms.  相似文献   
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Despite the maternal and infant morbidity associated with gestational diabetes mellitus (GDM), few modifiable risk factors have been identified. We explored the relation between recreational physical activity performed during the year before and during the first 20 weeks of pregnancy and the risk of GDM. 155 GDM cases and 386 normotensive, non-diabetic pregnant controls provided information about the type, intensity, frequency, and duration of physical activity performed during these time periods. Women who participated in any recreational physical activity during the first 20 weeks of pregnancy, as compared with inactive women, experienced a 48% reduction in risk of GDM (odds ratio [OR] = 0.52; 95% confidence interval [CI] 0.33-0.80). The number of hours spent performing recreational activities and the energy expended were related to a decrease in GDM risk. No clear patterns related to distance walked and pace of walking emerged. Daily stair climbing, when compared with no stair climbing, was associated with a 49-78% reduction in GDM risk (P for trend <0.011). Recreational physical activity performed during the year before the index pregnancy was also associated with statistically significant reductions in GDM risk, but women who engaged in physical activity during both time periods experienced the greatest reduction in risk (OR = 0.40; 95% CI 0.23-0.68). These data suggest that recreational physical activity performed before and/or during pregnancy is associated with a reduced risk of GDM.  相似文献   
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65.
Introduction: Current treatment of Parkinson’s disease (PD) is limited to symptomatic dopaminergic therapy, while no interventions have been shown to slow down disease progression.

Areas covered: The following article highlights a group of PPAR-γ agonists called thiazolidinediones (TZDs), which are currently being tested for a putative disease-modifying benefit in PD, using pioglitazone as a prototypic compound. PPAR-γ is highly expressed in neurons of the substantia nigra and CNS immune cells. Preclinical data in rodent and primate support an effect of TZDs in preventing and/or arresting neurodegeneration and development of motor symptoms. Although no data on the neuroprotective effect of TZDs is currently available, a clinical trial is ongoing where the primary objective is to assess pioglitazone’s impact on the progression of PD. The trial is also evaluating the drug’s safety concerns.

Expert opinion: The efficacy data from clinical trials must be carefully weighed against the safety concerns. However, given the solid preclinical data, and since the safety data are not yet fully conclusive and limited to the diabetic population, PPAR-γ research in PD can continue with caution. Ideally, drug discovery and development efforts will lead to the identification of new compounds with reduced risk of peripheral side effects.  相似文献   

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In 2008, the Alberta government released the Alberta Nutrition Guidelines for Children and Youth (ANGCY) as a resource for child care facilities to translate nutrition recommendations into practical food choices. Using a multiple case study method, early adoption of the guidelines was examined in two child care centres in Alberta, Canada. Key constructs from the Diffusion of Innovations framework were used to develop an interview protocol based on the perceived characteristics of the guidelines (relative advantage, compatibility, complexity, trialability and observability) by child care providers. Analysis of the ANGCY was conducted by a trained qualitative researcher and validated by an external qualitative researcher. This entailed reviewing guideline content, layout, organisation, presentation, format, comprehensiveness and dissemination to understand whether characteristics of the guidelines affect the adoption process. Data were collected through direct observation, key informant interviews and documentation of field notes. Qualitative data were analysed using content analysis. Overall, the guidelines were perceived positively by child care providers. Child care providers found the guidelines to have a high relative advantage, be compatible with current practice, have a low level of complexity, easy to try and easy to observe changes. It is valuable to understand how child care providers perceive characteristics of guidelines as this is the first step in identifying the needs of child care providers with respect to early adoption and identifying potential educational strategies important for dissemination.  相似文献   
68.
Collagen 6‐related dystrophies and myopathies (COL6‐RD) are a group of disorders that form a wide phenotypic spectrum, ranging from severe Ullrich congenital muscular dystrophy, intermediate phenotypes, to the milder Bethlem myopathy. Both inter‐ and intrafamilial variable expressivity are commonly observed. We present clinical, immunohistochemical, and genetic data on four COL6‐RD families with marked intergenerational phenotypic heterogeneity. This variable expression seemingly masquerades as anticipation is due to parental mosaicism for a dominant mutation, with subsequent full inheritance and penetrance of the mutation in the heterozygous offspring. We also present an additional fifth simplex patient identified as a mosaic carrier. Parental mosaicism was confirmed in the four families through quantitative analysis of the ratio of mutant versus wild‐type allele (COL6A1, COL6A2, and COL6A3) in genomic DNA from various tissues, including blood, dermal fibroblasts, and saliva. Consistent with somatic mosaicism, parental samples had lower ratios of mutant versus wild‐type allele compared with the fully heterozygote offspring. However, there was notable variability of the mutant allele levels between tissues tested, ranging from 16% (saliva) to 43% (fibroblasts) in one mosaic father. This is the first report demonstrating mosaicism as a cause of intrafamilial/intergenerational variability of COL6‐RD, and suggests that sporadic and parental mosaicism may be more common than previously suspected.  相似文献   
69.

Context

Compromise to the acromiohumeral distance has been reported in participants with subacromial impingement syndrome compared with healthy participants. In clinical practice, patients with subacromial shoulder impingement are given strengthening programs targeting the lower trapezius (LT) and serratus anterior (SA) muscles to increase scapular posterior tilt and upward rotation. We are the first to use neuromuscular electrical stimulation to stimulate these muscle groups and evaluate how the muscle contraction affects the acromiohumeral distance.

Objective

To investigate if electrical muscle stimulation of the LT and SA muscles, both separately and simultaneously, increases the acromiohumeral distance and to identify which muscle-group contraction or combination most influences the acromiohumeral distance.

Design

Controlled laboratory study.

Setting

Human performance laboratory.

Patients or Other Participants

Twenty participants (10 men and 10 women, age = 26.9 ± 8.0 years, body mass index = 23.8) were screened.

Intervention(s)

Neuromuscular electrical stimulation of the LT and SA.

Main Outcome Measure(s)

Ultrasound measurement of the acromiohumeral distance.

Results

Acromiohumeral distance increased during contraction via neuromuscular electrical stimulation of the LT muscle (t19 = −3.89, P = .004), SA muscle (t19 = −7.67, P = .001), and combined LT and SA muscles (t19 = −5.09, P = .001). We observed no differences in the increased acromiohumeral distance among the 3 procedures (F2,57 = 3.109, P = .08).

Conclusions

Our results supported the hypothesis that the muscle force couple around the scapula is important in rehabilitation and scapular control and influences acromiohumeral distance.Key Words: subacromial impingement syndrome, real-time ultrasound, rehabilitation

Key Points

  • Acromiohumeral distance increased during neuromuscular electrical stimulation of the lower trapezius muscle, serratus anterior muscle, and combined lower trapezius and serratus anterior muscles.
  • The increase in acromiohumeral distance was not different among the 3 neuromuscular electrical-stimulation procedures.
  • The muscle force couple around the scapula is important in rehabilitation and scapular control and influences acromiohumeral distance.
Optimal upper limb function depends on the ability to statically and dynamically position the shoulder girdle in an optimal coordinated fashion.1,2 Suboptimal motor control is considered a risk factor for developing shoulder subacromial impingement syndrome.314 Alterations in scapular motion have been linked to a decrease in serratus anterior (SA) muscle activity, an increase in upper trapezius muscle activity, and an imbalance of forces between the upper and lower parts of the trapezius muscle.15 This may adversely affect scapular positioning, resulting in reduced scapular upward rotation, increased anterior scapular tilt, and scapular winging.4,9,16 In turn, scapular upward rotation and posterior tilt are considered vital for elevating the acromion and, hence, widening the subacromial space, thereby preventing impingement of the subacromial tissues.17,18 Atalar et al19 suggested that reduced scapular mobility led to a decrease in acromiohumeral distance (AHD) during upper extremity abduction. Therefore, when developing rehabilitation strategies for patients with subacromial impingement syndrome, correcting neuromuscular control of the SA and trapezius muscles is important.20,21Overall, researchers22,23 have supported the theory that altered activity in the scapular rotator muscles is present in patients with subacromial impingement syndrome and have highlighted the role of scapular rotator muscle training as an essential component of shoulder rehabilitation. A clinical practice strategy, supported by research data, recommends that patients who have subacromial shoulder impingement and present with primary movement dysfunction of the scapula should be given strengthening programs targeting the lower trapezius (LT) and SA muscles.24,25 The LT muscle is reported to increase posterior scapular tilt, and the SA muscle is believed to increase upward rotation of the scapula.2 In turn, posterior scapular tilt and upward scapular rotation are associated with increased AHD.17,18Authors9,23,2629 of electromyographic (EMG) studies have tested muscle activity in participants with subacromial impingement syndrome and in healthy persons. In patients with subacromial impingement syndrome, when the upper extremity was at rest and during flexion and abduction, the EMG signal amplitude of the upper trapezius muscle increased, whereas the EMG signal amplitude of the LT and SA muscles decreased.30,31 These researchers have considered the immediate changes in the surface EMG activity of the scapular rotator muscles. However, to our knowledge, we are the first to use neuromuscular electrical stimulation (NMES) to stimulate the muscle groups of the LT and SA and evaluate the effect of muscle contraction in these muscles on the AHD. Neuromuscular electrical stimulation is used for various medical applications and is a common intervention during rehabilitation to improve function and motor control,32 prevent and treat shoulder pain,33 increase range of motion,34 and facilitate changes in muscle action and performance.35 Therefore, the purpose of our study was to investigate whether stimulation of the LT and the SA muscles (separately and simultaneously) with NMES would increase the AHD and to investigate which muscle-group contraction or combination most influenced the AHD.  相似文献   
70.

Background

Mental health problems are common after pediatric traumatic brain injury (TBI). Many patients in need of mental health services do not receive them, but studies have not consistently used prospective and objective methods or followed samples for more than 1 year.

Objective

To examine adolescents’ use of mental health services after TBI.

Design

Secondary analysis from multicenter prospective randomized controlled trial.

Setting

Five level 1 U.S. trauma centers.

Participants

Adolescents aged 12-17 years with moderate-to-severe TBI were recruited for a randomized clinical trial (n = 132 at baseline, 124 at 6 months, 113 at 12 months, and 101 at 18 months).

Methods

Participants were randomly assigned to counselor-assisted problem-solving or Internet resource comparison. Follow-up assessments were completed at 6, 12, and 18 months after baseline. Generalized estimating equations with a logit link were used to examine use of mental health services. Treatment group and participant impairment were examined as predictors of use.

Main Outcome Measurements

Mental health care use was measured with the Service Assessment for Children and Adolescents; daily functioning and clinical outcome with the Child and Adolescent Functional Assessment Scale; behavioral and emotional functioning with the Child Behavior Checklist; and executive dysfunction with the Behavior Rating Inventory of Executive Function.

Results

Use of mental health services ranged from 22% to 31% in the 2 years post-TBI. Participants with impairments were about 3 times more likely than those without impairments to receive services (odds ratio 4.61; 95% confidence interval 2.61-8.14; P < .001). However, 50%-68% of patients identified as impaired had unmet mental health care needs.

Conclusions

Less than one half of adolescents with behavioral health needs after TBI received mental health services. Future studies are needed to examine barriers associated with seeking services after TBI and psychoeducation as preventive care for this population.

Level of Evidence

II  相似文献   
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