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41.
The aims of this study were to evaluate the weekly and annual cumulative radiofrequency-electromagnetic field (RF-EMF) exposure attributed to mobile phone (MP) use, and assess whether a novel app (Quanta Monitor?) could be employed in a small human sample to characterise the RF-EMF exposures associated with the use of MPs. Ten participants provided their two months’ daily objective data on their MP exposures (i.e. transmitted and received power densities) attributed to different modes of MP usage such as cellular calls, cellular data and Wi-Fi. The results demonstrated that total transmitted power density (cellular phone calls, data and Wi-Fi surfing) could be many orders of magnitude higher than that from the total received power density. Of the total transmitted power density, cellular data use contributed the largest portion. Our study showed that Quanta Monitor? could be employed in prospective assessment of exposures to MPs in epidemiological studies.  相似文献   
42.

Aim

To provide a systematic review of the existing theory, framework, systems and instruments for tracing and evaluating quality in rural health services.

Subjects and methods

We searched six electronic databases up to March 2016. Observational studies of quality assessment of rural health services using theoretical models were included. Ekman’s scale was used to evaluate the quality of the included studies.

Results

A total of 18 studies, published between 2001 and 2015, met the inclusion criteria. The corresponding authors for most of them (7, 44%) are from Chinese institutions and three (3, 17%) from Australian institutions. Five studies (28%) focused on township hospitals. Primary health care quality was reported in five studies (28%), followed by clinical service in four (22%). More than half of the studies (61%) were considered of high quality, and the remainder was of moderate quality. These studies applied 16 theoretical systems, including the model/pattern (4, 25%), method/tool (7, 44%) and framework of the theory (5, 31%). Most of the theoretical models (14, 88%) obtained positive observations. In addition, the conceptual model (6, 36%) and TOPSIS method (2, 13%) were more frequently reported.

Conclusion

Although most of the current studies were considered to have high-quality and positive results, there were limitations in the number of publications and research on theoretical systems. The lacks of unified standards and comprehensive evaluation are important issues that need to be pointed out and resolved.
  相似文献   
43.
44.

Purpose

The number of single households has increased worldwide with middle-aged people in such households indicating the highest increase. However, there is a lack of studies on the topic. This study estimated the quality of life (QOL) by household type for middle-aged Korean adults.

Methods

We used the Korea National Health and Nutrition Examination Survey data from 2007 to 2015. QOL was analyzed using EQ-5D 3-level, and demographic and health-related variables were included as confounders. The households were divided into single household, married couple without child, other one-generation, married couple with child, single parent with child, other two-generation, and three-generation. Logistic regression using level, strata, and sample weight of data was performed based on average QOL.

Results

This study included 18,147 responders aged 45–64 years, with single households constituting 5.7%. Single households having average or less QOL were 48.4%, with men and women constituting 40.1 and 53.3%, respectively. After adjusting socioeconomic factors and health-related factors, the odds ratio (OR) of single households was 1.375 (95% CI 1.122–1.684) compared to the three-generation group. According to the sex, the OR of single households with men was higher (OR 1.552, 95% CI 1.121–2.149). However, no significance was found in women.

Conclusions

The study results revealed that middle-aged people in single households had low QOL than those in multi-person households. The trend was significantly observable in men than in women. Because middle-aged adults might transform into elderly with low QOL, program development and social support for middle-aged adults in single households should be provided.
  相似文献   
45.

Background

Epidemiological studies consistently report a 90% prevalence of foot pain. Mechanical and other non-pharmacological interventions such as orthoses and footwear can play an important role in managing foot pathology in patients whose systemic disease is controlled. The effectiveness of treatment with insoles has been examined in various randomised controlled trials, which have reported immediate clinical improvements, with reduced foot pain and disability and enhanced functionality. The aim of this systematic review is to determine the effectiveness of foot orthoses in patients with rheumatoid arthritis (RA), in comparison with other treatments, in terms of enhanced disability and reduced pain.

Methods

A systematic review and meta-analysis was conducted of a number of randomised controlled trials focusing on patients with RA. The search was conducted in Cochrane, CINAHL, PubMed, EMBASE, SCOPUS and Cuiden, by means of an independent peer review. The Mesh terms and fields used were foot, ankle, joint, RA, foot, orthosis, insole and foot orthosis.

Results

Of the initial 118 studies considered, 5 were included in the final systematic review and meta-analysis. These five studies had enrolled a total of 301 participants, with follow-up periods ranging from 4 to 36 months. Although the use of orthoses seems to alleviate foot pain, our meta-analysis did not reveal statistically significant differences between control and intervention groups regarding long- and short-term pain relief and/or reduced disability.

Conclusions

Foot orthoses can relieve pain and disability and enhance patients, but no significant differences were found between control and intervention groups.
  相似文献   
46.
47.

Purpose

To conduct a systematic literature review of the reliability, construct validity, and responsiveness of the SF-36® Health Survey (SF-36) in patients with ulcerative colitis (UC).

Methods

We performed a systematic search of electronic medical databases to identify published peer-reviewed studies which reported scores from the eight scales and/or two summary measures of the SF-36 collected from adult patients with UC. Study findings relevant to reliability, construct validity, and responsiveness were reviewed.

Results

Data were extracted and summarized from 43 articles meeting inclusion criteria. Convergent validity was supported by findings that 83% (197/236) of correlations between SF-36 scales and measures of disease symptoms, disease activity, and functioning exceeded the prespecified threshold (r ≥ |0.40|). Known-groups validity was supported by findings of clinically meaningful differences in SF-36 scores between subgroups of patients when classified by disease activity (i.e., active versus inactive), symptom status, and comorbidity status. Responsiveness was supported by findings of clinically meaningful changes in SF-36 scores following treatment in non-comparative trials, and by meaningfully larger improvements in SF-36 scores in treatment arms relative to controls in randomized controlled trials. The sole study of SF-36 reliability found evidence supporting internal consistency (Cronbach’s α ≥ 0.70) for all SF-36 scales and test–retest reliability (intraclass correlation coefficient ≥0.70) for six of eight scales.

Conclusions

Evidence from this systematic literature review indicates that the SF-36 is reliable, valid, and responsive when used with UC patients, supporting the inclusion of the SF-36 as an endpoint in clinical trials for this patient population.
  相似文献   
48.

Purpose

Most computerized adaptive testing (CAT) applications in patient-reported outcomes (PRO) measurement to date are reliability-centric, with a primary objective of maximizing measurement efficiency. A key concern and a potential threat to validity is that, when left unconstrained, individual CAT administrations could have items with systematically different attributes, e.g., sub-domain coverage. This paper aims to provide a solution to the problem from an optimal test design framework using the shadow-test approach to CAT.

Methods

Following the approach, a case study was conducted using the PROMIS® (Patient-Reported Outcomes Measurement Information System) fatigue item bank both with empirical and simulated response data. Comparisons between CAT administrations without and with the enforcement of content and item pool usage constraints were examined.

Results

The unconstrained CAT exhibited a high degree of variation in items selected from different substrata of the item bank. Contrastingly, the shadow-test approach delivered CAT administrations conforming to all specifications with a minimal loss in measurement efficiency.

Conclusions

The optimal test design and shadow-test approach to CAT provide a flexible framework for solving complex test-assembly problems with better control of their domain coverage than for the conventional use of CAT in PRO measurement. Applications in a wide array of PRO domains are expected to lead to more controlled and balanced use of CAT in the field.
  相似文献   
49.

Purpose

Measurement invariance issues should be considered during test construction. In this paper, we provide a conceptual overview of measurement invariance and describe how the concept is implemented in several different statistical approaches. Typical applications look for invariance over things such as mode of administration (paper and pencil vs. computer based), language/translation, age, time, and gender, to cite just a few examples. To the extent that the relationships between items and constructs are stable/invariant, we can be more confident in score interpretations.

Methods

A series of simulated examples are reported which highlight different kinds of non-invariance, the impact it can have, and the effect of appropriately modeling a lack of invariance. One example focuses on the longitudinal context, where measurement invariance is critical to understanding trends over time. Software syntax is provided to help researchers apply these models with their own data.

Results

The simulation studies demonstrate the negative impact an erroneous assumption of invariance may have on scores and substantive conclusions drawn from naively analyzing those scores.

Conclusions

Measurement invariance implies that the links between the items and the construct of interest are invariant over some domain, grouping, or classification. Examining a new or existing test for measurement invariance should be part of any test construction/implementation plan. In addition to reviewing implications of the simulation study results, we also provide a discussion of the limitations of current approaches and areas in need of additional research.
  相似文献   
50.
In this study, we aimed to find out the biodegradation efficiency of some soil fungi types on herbicide acetochlor with acetochlor active material, chemical oxygen demand (COD), biochemical oxygen demand (BOD5) and total organic carbon (TOC) parameters. We also try to determine the population dynamics of these fungi via turbidity. The fungi cultures were isolated from agricultural field in in Thrace region of Turkey. Each fungi enriched in malt extract broth media and 1 mL of these enriched media was inoculated into 100 mL of acetochlor solutions that suggested for using application concantrations in agricultural field for farmers (11000 mg L?1) for sunflower and corn agriculture. Bioremediation results of acetochlor have shown different results according to the types of fungi. Our results indicate that Tolypocladium geodes and Cordyceps cicadae might be used in acetochlor bioremediation with a significant acetochlor, COD, TOC and BOD5 reduction and can be used for rehabilitation of agricultural fields or receiving environments for removal the opposite effects of acetochlor or other herbicides.  相似文献   
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