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1.

Objective

The advantage of arteriovenous fistulas (AVFs) in older patients requiring dialysis is controversial. We reviewed our vascular access experience in patients ≥70 years of age (older group) compared with younger patients.

Methods

We analyzed consecutive patients who underwent access surgery between 2013 and 2016. Primary success (PS) and primary patency (PP) data were analyzed between the older and younger groups before and after propensity score matching of the patients' characteristics and access composition. PS was defined as the achievement of access function that was amenable to two sessions of successful cannulation without early occlusion or maturation failure requiring revision. PP was defined as the time with uninterrupted patency without intervention.

Results

A total of 594 consecutive accesses were created among 563 patients, of whom 119 were allocated into each group after propensity score matching. In the whole cohort, 193 accesses (32.5%) were performed in older patients. AVFs were performed in 130 (67.4%) older patients and 293 (73.1%) younger patients. Regarding AVFs, the PS rate (83.6% in the older group vs 94.3% in the younger group; P = .001) and the overall PP at 6 and 12 months (73.1% and 57.1%, respectively, in the older group vs 86.7% and 77.7%, respectively, in the younger group; P = .009) were lower in the older group than in the younger group. However, no differences were found in the PS and PP rates for arteriovenous grafts between groups. Regarding the AVF location, the PS rate for forearm AVFs was significantly lower in the older group than in the younger group (76% vs 93%; P < .001); however, the PS rate of the upper arm was not different between the groups (94% vs 97%; P = .425). In the patients with PS, the PP rate of AVFs was similar between the two groups. In the older group with forearm AVFs, the median diameter of the radial artery was larger in the patients with PS than in the patients without PS (2.20 mm with PS vs 2.00 mm without PS; P = .008). The propensity score matching results demonstrated similar trends for the whole cohort, with lower PS (P = .042) and PP rates (P = .023) for AVF in the older group.

Conclusions

The outcomes after AVF were poorer in the older group than in the younger group, which was primarily due to unsatisfactory outcomes in patients with forearm AVFs. Thus, stricter criteria, especially regarding the radial artery diameter, should be applied for forearm AVFs in older patients, and additional research is necessary to delineate the risk factors for primary failure.  相似文献   
2.
p-Carboxyphenoxy propane (CPP) prepolymer consisting of 4 units and sebacic acid (SA) prepolymer consisting of about 10 units were synthesized by reacting CPP and SA in the presence of excess acetic anhydride, respectively. Polyanhydride, poly(CPP-SA) copolymers were copolymerized by a melt polycondensation process with a mixture of CPP and SA prepolymer. Copolymers of average molecular weight up to 110,000 g/mol were achieved. The crystallinity of poly(CPP-SA) copolymers was decreased by the addition of the CPP homopolymer segment to SA homopolymer. Poly(CPP-SA) copolymers gradually degraded for period of 10 days. No large difference of weight loss observed according to molecular weight variation of poly(CPP-SA) copolymers. BCNU release from wafers fabricated by poly(CPP-SA) showed a sustained release pattern with no initial burst and delay of drug release.  相似文献   
3.
An investigation was carried out into how stimulation frequency and stimulation history affect the potentiation of muscle force during 20s of constant stimulation of the two knee extensors in isometric conditions. Stimulation frequency significantly affected the potentiation pattern: low-frequency (2.5–10 Hz) stimulation showed a reduction and subsequent enhancement of force, and high-frequency (14.3–25 Hz) stimulation showed only enhancement of force. The degree of enhancement in force and time-to-peak decreased with the stimulation frequency. Whereas conditioning stimulation (both 40 Hz and 14.3 Hz) significantly enhanced the muscle force above 85%, following main stimulation (14.3 Hz) after short rest (10 s and 50 s, respectively) induced little force enhancement (below 8%). In particular, when the frequency of the conditioning stimulation was 14.3 Hz, the initial force at the main stimulation showed a very similar value to the final force value of the conditioning stimulation (above 90% similarity). The potentiated twitch force slowly decayed during rest, with an average time constant of 2.4 min. These observations indicate that muscle potentiation depends on the stimulation frequency and stimulation history, and therefore a computer model of potentiation can play an important role in predicting muscle force and body movement induced by electrical stimulation.  相似文献   
4.
To provide financial protection against catastrophic illness, the Korean government expanded the National Health Insurance (NHI) benefit coverage for cancer patients in 2005. This paper examined whether the policy improved the income-related equality in health care utilization. This study analyzed the extent to which the policy improved income-related equality in outpatient visits, inpatient days, and inpatient and outpatient care expenditure based on triple difference estimator. Using nationwide claims data of the NHI from 2002 to 2004 and from 2006 to 2010, we compared cancer patients as a treatment group with liver disease as a control group and low-income group with the highest-income group. The results showed that the extension of NHI benefits coverage led to an increase in the utilization of outpatient services across all income groups, but with a greater increase for the low-income groups, among cancer patients. Moreover, the policy led to a less decrease in the utilization of inpatient services for the low-income group while it decreased across all income groups. Our finding suggests that the extension of NHI benefits coverage improved the income-related equality in health care utilization.  相似文献   
5.
6.
7.
Little data on cutaneous squamous cell carcinoma (SCC) epidemiology within the United States are currently available. Prior studies have focused on populations outside of the United States or been limited to regions within the US. In this study, prospective data were collected via biennial questionnaires from a total of 261,609 participants, which included women in the Nurses’ Health Study (NHS, 1976–2008) and Nurses’ Health Study II (NHS II, 1989–2009), and men in the Health Professionals Follow-Up Study (HPFS, 1986–2008). History of physician-diagnosed invasive SCC was confirmed by pathology record review. Over the entire follow-up period for each cohort, there were 1,265 invasive SCC cases per 100,000 persons in the NHS cohort, 389 cases per 100,000 persons in NHS II, and 2,154 cases per 100,000 persons in HPFS. An 18-year follow-up of participants in these cohorts revealed increasing invasive SCC incidence rates over time, with rates for men being consistently higher than those for women. In women, a larger proportion of invasive SCC lesions occurred on the lower extremities as compared to men (21 % in NHS vs. 6 % in HPFS, p < 0.0001; 14 % in NHS II vs. 6 % in HPFS, p < 0.0001), while in men, a larger proportion occurred on the head/neck (43 % in NHS vs. 60 % in HPFS, p < 0.0001; 48 % in NHS II vs. 60 % in HPFS, p < 0.0001). In summary, invasive SCC incidence rates among US men have been greater than those for women with distinct sites of common occurrence between men and women.  相似文献   
8.
Aberrant activation of cancer‐derived mutants of the epidermal growth factor receptor (EGFR) is closely associated with cancer pathogenesis and is thought to be mediated through multiple tyrosine phosphorylations within the C‐terminal domain. Here, we examined the consequences of the loss of these C‐terminal phosphorylation sites on cellular transformation in the context of lung‐cancer‐derived L858R, exon 19 deletion and exon 20 insertion mutant EGFR. Oncogenic EGFR mutants with substitution of the 10 potential C‐terminal tyrosine autophosphorylation sites for phenylalanine (CYF10) were still able to promote anchorage‐independent growth in soft agar at levels comparable to the parental L858R or exon19 deletion or exon 20 insertion mutants with intact autophosphorylation sites. Furthermore, these CYF10 mutants retained the ability to transform Ba/F3 cells in the absence of IL‐3. Bead‐based phosphorylation and immunoprecipitation analyses demonstrated that key EGFR‐associated proteins—including Grb2 and PLC‐γ—are neither phosphorylated nor bound to CYF10 mutants in transformed cells. Taken together, we conclude that tyrosine phosphorylation is not required for oncogenic activity of lung‐cancer‐derived mutant EGFR, suggesting these mutants can lead to cellular transformation by an alternative mechanism independent of EGFR phosphorylation.  相似文献   
9.

Background

A great number of studies have been conducted to examine the relationship between nurse staffing and patient outcomes. However, none of the reviews have rigorously assessed the evidence about the effect of nurse staffing on nurse outcomes through meta-analysis.

Purpose

The purpose of this review was to systematically assess empirical studies on the relationship between nurse staffing and nurse outcomes through meta-analysis.

Methods

Published peer-reviewed articles published between January 2000 and November 2016 were identified in CINAHL, PubMed, PsycINFO, Cochrane Library, EBSCO, RISS, and DBpia databases.

Findings

This meta-analysis showed that greater nurse-to-patient ratio was consistently associated with higher degree of burnout among nurses (odds ratio: 1.07; 95% confidence interval [CI]: 1.04–1.11), increased job dissatisfaction (odds ratio: 1.08; 95% CI: 1.04–1.11), and higher intent to leave (odds ratio: 1.05; 95% CI: 1.02–1.07). With respect to needlestick injury, the overall effect size was 1.33 without statistical significance.

Discussion

The study findings demonstrate that higher nurse-to-patient ratio is related to negative nurse outcomes. Future studies assessing the optimal nurse-to-patient ratio level in relation to nurse outcomes are needed to reduce adverse nurse outcomes and to help retain nursing staff in hospital settings.  相似文献   
10.
BackgroundThis study examined the effects of ankle and knee joint immobilization on postural control in healthy young adults while standing.MethodsThe 24 participants included in this study participated in postural standing tests under four different constraint conditions: free joints, ankle immobilization only, knee immobilization only, and ankle‐knee immobilization. Tests were performed using a commercial balancing equipment (BiodexTM, Inc., NY, USA) and software.ResultsThe overall limit-of-stability score and duration to completion of task were obtained at 75% limit‐of‐stability (moderate level of difficulty). The overall limit‐of‐stability score of free joints (34.5 ± 9.1) were significantly different with the ankle immobilization only (26.0 ± 11.6), and ankle-knee immobilization (26.4 ± 7.4) conditions. The test duration increased in the following order: free joints (57.8 ± 10.9), knee immobilization only (62.5 ± 14.0), ankle immobilization only (68.0 ± 14.9), and ankle-knee immobilization (69.4 ± 17.7). The duration of the free joint condition greatly decreased than ankle immobilization only and ankle-knee immobilization conditions.ConclusionsThe ankle and knee joints have sufficient range of motion to prevent falls related to decrease postural stability due to insufficient range of motion or to improve postural stability.  相似文献   
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