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31.
OBJECTIVE: Aggregation (i.e., meta-ethnography or meta-synthesis) of qualitative studies remains relatively rare and controversial. We have attempted this procedure within an investigation of patient priorities and evaluations of primary care in order to triangulate an instrument development process as well as explore associated dilemmas. METHODS: The procedures included a literature search of qualitative research on patient priorities and evaluations and creation of a framework for quality assessment of retrieved papers. The tool for the evaluation of quality in qualitative studies was piloted, refined, and applied to the retrieved literature. The articles were equally distributed between two teams in random fashion, and inter-rater agreement calculated. Finally, we formulated and applied a strategy for aggregation of data from included papers that allowed comparison to a systematic review of quantitative studies on the topic. RESULTS: Thirty-seven articles met inclusion criteria. Twenty-four of these articles were of sufficient quality to be included in the qualitative aggregation. Inter-rater agreement ranged from 0.22 to 0.77 and 0.38 to 0.60 for pair and assessor comparisons, respectively. The aggregation strategy enabled synthesis within sub-categories of the heterogeneous papers. CONCLUSIONS: We have devised a modestly reliable instrument to assess the quality of qualitative work. The procedure for quality assessment and aggregation appears to be both feasible and potentially useful, though both theoretical and practical problems underline the need for further refinement prior to widespread utilization of this approach. PRACTICE IMPLICATIONS: An instrument to assess the quality of qualitative work within the context of aggregation efforts is described. Calculating inter-rater reliability in this framework can support future quality assessments. A method of breaking a heterogeneous collection of included papers into sub-categories to enable aggregation of qualitative studies is applied and demonstrates its feasibility and potential usefulness.  相似文献   
32.
CpG DNA stimulates autoreactive immature B cells in the bone marrow   总被引:2,自引:0,他引:2  
Polyclonal activation of developing B cells is an injurious process, because most of these cells are nontolerant and express autoreactive receptors. CpG DNA is a polyclonal activator of mature B cells, but its effect on developing B cells is unclear. We tested whether developing, nontolerant B cells are responsive to mitogenic stimulation by CpG DNA and whether such a stimulus can interfere with the establishment of central tolerance. We found that developing B cells express Toll-like receptor 9 and undergo a polyclonal response to CpG DNA stimulation, as revealed by proliferation and differentiation to antibody-producing cells. In vitro and ex vivo experiments revealed that stimulation with CpG DNA protects immature B cells from negative selection imposed by apoptosis and receptor editing and results in the production of autoantibodies. Finally, we found that in vivo administration of CpG DNA activates immature B cells in the bone marrow and suppresses the expression of recombination-activating genes in a mouse model of central tolerance and receptor editing. These results suggest that mitogenic signals provided by CpG DNA stimulate nontolerant immature B cells in the bone marrow and have the potential to interfere with central tolerance.  相似文献   
33.
Aims: Approximately 1.25 million people in the US have type 1 diabetes mellitus (T1DM), a chronic metabolic disease that develops from the body’s inability to produce insulin, and requires life-long insulin therapy. Poor insulin adherence may cause severe hypoglycemia (SHO), leading to hospitalization and long-term complications; these, in turn, drive up costs of SHO and T1DM overall. This study’s objective was to estimate the prevalence and costs of SHO-related hospitalizations and their additional longer-term impacts on patients with T1DM using basal-bolus insulin.

Methods: Using Truven MarketScan claims, we identified adult T1DM patients using basal-bolus insulin regimens who were hospitalized for SHO (inpatient SHO patients) during 2010–2015. Two comparison groups were defined: those with outpatient SHO-related encounters only, including emergency department (ED) visits without hospitalization (outpatient SHO patients), and those with no SHO- or acute hyperglycemia-related events (comparison patients). Lengths of stay and SHO-related hospitalization costs were estimated and propensity score and inverse probability weighting methods were used to adjust for baseline differences across the groups to evaluate longer-term impacts.

Results: We identified 8,734 patients, of which 4.2% experienced at least one SHO-related hospitalization. Among those who experienced SHO (i.e. of those in the inpatient and outpatient SHO groups), 31% experienced at least one SHO-related hospitalization, while 9% were treated in the ED without subsequent hospitalization. Approximately 79% of patients were admitted directly to the hospital; the remainder were first assessed or treated in the ED. The inpatient SHO patients stayed in the hospital, including time in the ED, for 1.7 days and incurred $3551 in costs. About one-third of patients were hospitalized again for SHO. Inpatient SHO patients incurred significantly higher monthly costs after their initial SHO-related hospitalization than patients in the two other groups ($2084 vs $1313 and $1372), corresponding to 59% or 52% higher monthly costs for inpatient SHO patients.

Limitations: These analyses excluded patients who did not seek ED or hospital care when faced with SHO; events may have been miscoded; and we were not able to account for clinical characteristics associated with SHO, such as insulin dose and duration of diabetes, or unmeasured confounders.

Conclusions: The burden associated with SHO is not negligible. About 4% of T1DM patients using basal-bolus insulin regimens are hospitalized at least once due to SHO. Not only did those patients incur the costs of their SHO hospitalization, but they also incur red at least $712 (52%) more in costs per month after their hospitalization than outpatient SHO or comparison patients. Reducing SHO events can help decrease the burden associated with SHO among patients with T1DM.  相似文献   

34.

Background

Higher-level gait disorder (HLGD) in older adults is characterized by postural instability, stepping dysrhythmicity, recurrent falls and progressive immobility. Cognitive impairments are frequently associated with HLGD.

Objectives

The aim of this study was to compare gait and cognitive performance before and after the use of rivastigmine in patients with HLGD, free from cognitive impairment or Parkinsonism.

Methods

Fifteen non-demented patients with HLGD (age 79.2 ± 5.9 years; 11 women; Mini-Mental State Examination [MMSE] 28.3 ± 1.4) received escalating doses of rivastigmine for 12 weeks in an open-label, pilot study. They were assessed before and after treatment (week 0 and week 12), and after a 4-week washout period (week 16). Assessments included the Mindstreams computerized neuropsychological battery, Activities-specific Balance Confidence Scale, State-Trait Anxiety Inventory, Geriatric Depression Scale, Timed Up and Go (TUG) test, gait speed and stride time variability. One-way multiple analysis of variance tests for repeated measures were used, and Pillai’s trace test was considered as robust to investigate significant differences.

Results

The mean dose of rivastigmine during the 8–12 week period was 5.1 ± 2.3 mg/day. A positive effect was observed on the Mindstreams memory subscale and anxiety scores [Pillai’s trace: F(6,724) = 0.508, p = 0.010; and F(7,792) = 0.545, p = 0.006, respectively, over the course of the study] as well as on mobility (TUG test) [Pillai’s trace: F(4,863) = 0.448; p = 0.028], whereas gait speed and stride time variability did not change.

Conclusions

The use of relatively low-dose rivastigmine did not affect gait speed and stride time variability; however, the general mobility and anxiety were improved. These preliminary results warrant a larger, randomized, placebo-controlled study.  相似文献   
35.
36.
37.
ObjectiveDespite increased risks of nasolacrimal duct obstruction (NLDO) with age, and the continuous growth of the old population proportion, data on endoscopic dacryocystorhinostomy (eDCR) among the old is lacking. This study aims to evaluate long-term eDCR efficacy and safety in the old and oldest-old population.MethodsA retrospective case-control study of patients aged 80 ≤ (oldest-old) and 65–79 (old) compared with younger controls who underwent eDCR, between 2002 and 2017. Pre-, intra- and postoperative factors were collected using an integrated hospital-community system. Success rates were analyzed and measured at the first visit following surgery (immediate success), and after five years. Demographics, comorbidities, complications rates, and outcomes were compared between the groups.ResultsThe study groups included 52 oldest-old patients (mean age 83.4 ± 3.6), 127 old patients (72.3 ± 4.14) and 142 control patients (57.8 ± 18.0). The immediate and success rates were 94.2%, 93.7% and 90.8% and five-year success rates were 80.0%, 76.6% and 80% among oldest-old, old and controls, respectively. No significant differences in success rates were found, even despite higher comorbidity rates among the study's group (96 and 92.8% vs. 63.2%, among oldest-old, old and controls respectively, p <0.001). Intra- and postoperative complications rates were low in all groups.ConclusionsAmong older population, including oldest-old and old, eDCR safety and long-term outcomes are comparable with younger patients, suggesting that eDCR should be offered to NLDO patients, regardless of age.  相似文献   
38.

Objectives

The aim of the present study was to investigate the distribution of oral cariogenic bacteria among 12-year-old Palestinian children attending schools in East Jerusalem.

Materials and methods

Salivary levels of mutans streptococci (MS) and Lactobacilli (LB) were examined by semi-quantitative commercial kits and then correlated to social–demographic parameters.

Results

Overall, 52.1 % of the examined children presented the highest possible ranking score categories for MS bacteria, with only 5.4 % in the lowest category. Only 12.6 % of the school children presented the highest LB score, while 25 % had the lowest ranking score. Salivary MS levels in children attending private schools were lower than those of children in government schools and United Nations Relief and Works Agency (UNRWA) schools. Conversely, levels of LB were lowest in children attending UNRWA schools compared to government and private schools. Girls had significantly higher amounts of MS and LB than boys (p?=?0.001). Lower MS levels were significantly related to the following socioeconomic variables: higher father’s education level (p?=?0.037), higher mother’s education level (p?=?0.063), mother’s employment status (p?=?0.012), and lower home density (p?=?0.001). For LB, the only significant socioeconomic variable was higher father’s employment level, which was related to lower LB level (p?=?0.025).

Conclusions

Levels of MS and LB were found to be strongly related with socioeconomic status among Palestinian children in East Jerusalem. The relatively high prevalence of cariogenic bacteria suggests that oral care prevention and treatment demands special attention from the health care institutions and authorities.  相似文献   
39.

Background

Most personalized cancer care strategies involving DNA sequencing are highly reliant on acquiring sufficient fresh or frozen tissue. It has been challenging to comprehensively evaluate the genome of advanced prostate cancer (PCa) because of limited access to metastatic tissue.

Objective

To demonstrate the feasibility of a novel next-generation sequencing (NGS)–based platform that can be used with archival formalin-fixed paraffin-embedded (FFPE) biopsy tissue to evaluate the spectrum of DNA alterations seen in advanced PCa.

Design, setting, and participants

FFPE samples (including archival prostatectomies and prostate needle biopsies) were obtained from 45 patients representing the spectrum of disease: localized PCa, metastatic hormone-naive PCa, and metastatic castration-resistant PCa (CRPC). We also assessed paired primaries and metastases to understand disease heterogeneity and disease progression.

Intervention

At least 50 ng of tumor DNA was extracted from FFPE samples and used for hybridization capture and NGS using the Illumina HiSeq 2000 platform.

Outcome measurements and statistical analysis

A total of 3320 exons of 182 cancer-associated genes and 37 introns of 14 commonly rearranged genes were evaluated for genomic alterations.

Results and limitations

We obtained an average sequencing depth of >900X. Overall, 44% of CRPCs harbored genomic alterations involving the androgen receptor gene (AR), including AR copy number gain (24% of CRPCs) or AR point mutation (20% of CRPCs). Other recurrent mutations included transmembrane protease, serine 2 gene (TMPRSS2):v-ets erythroblastosis virus E26 oncogene homolog (avian) gene (ERG) fusion (44%); phosphatase and tensin homolog gene (PTEN) loss (44%); tumor protein p53 gene (TP53) mutation (40%); retinoblastoma gene (RB) loss (28%); v-myc myelocytomatosis viral oncogene homolog (avian) gene (MYC) gain (12%); and phosphatidylinositol-4,5-bisphosphate 3-kinase, catalytic subunit α gene (PIK3CA) mutation (4%). There was a high incidence of genomic alterations involving key genes important for DNA repair, including breast cancer 2, early onset gene (BRCA2) loss (12%) and ataxia telangiectasia mutated gene (ATM) mutations (8%); these alterations are potentially targetable with poly(adenosine diphosphate-ribose)polymerase inhibitors. A novel and actionable rearrangement involving the v-raf murine sarcoma viral oncogene homolog B1 gene (BRAF) was also detected.

Conclusions

This first-in-principle study demonstrates the feasibility of performing in-depth DNA analyses using FFPE tissue and brings new insight toward understanding the genomic landscape within advanced PCa.  相似文献   
40.
Older age is an independent predictor of mortality after percutaneous coronary intervention (PCI) in patients with Non-ST elevation Acute Coronary Syndrome (ACS). GPIIb/IIIa inhibitors are proved to improve outcome in high risk patients, but conflicting data are available about the effects of these inhibitors in elderly. Accordingly, we studied a consecutive population of elderly patients undergoing PCI for Non-ST elevation ACS. A total of 500 patients were divided in: GPI group (247 pts; mean age 77 ± 1.9 years) treated by stenting plus abciximab and, no GPI group (253 pts; mean age 77 ± 2.4 years) treated by stenting alone. Propensity analysis was used to account for the nonrandomized use of GPIIb/IIIa inhibitors. During hospitalization, incidence of death was similar among groups (3.2% vs 4.6%) without difference regarding incidence of major (1.6% vs 1.1%) and minor bleedings (4% vs 3%). At long-term follow-up the rate of death was significantly lower in GPI group (4.5% vs 12.3%; p = 0.002) as well as the rate of acute myocardial infarction (2.8% vs 11.1%; p = 0.0001), and pre-PCI (5.7% vs 13.4%; p = 0.003). Cox regression analysis identified abciximab use as an independent predictor of lower long-term major adverse cardiac event (MACE) after adjustment for propensity score (Exp (B) 0.620, 95%CI 0.394–0.976, p = 0.039). Our results suggest that addition of abciximab to stenting improves outcome in elderly patients with Non-ST elevation ACS, leading to an absolute benefit for reduction of death and MACE, with an acceptable rate of major and minor bleedings.  相似文献   
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