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981.

INTRODUCTION

Introducing laparoscopic colorectal surgery is a challenge to the whole surgical team. It is usual for an assistant to hold the laparoscope and be responsible for the surgeon''s view of the operative field and a lack of expertise in the assistant can add significant difficulties. The EndoAssist™ is a robotic device that replaces the human assistant and ensures steady visualisation of the operative field and a view which can be controlled by the surgeon. This study describes its use in the introduction of laparoscopic colorectal surgery to a unit.

PATIENTS AND METHODS

The EndoAssist was employed for the introduction of laparoscopic colorectal surgery in a unit with previous experience of this device for laparoscopic cholecystectomy. It was used in a consecutive series of 77 laparoscopic colectomy operations.

RESULTS

The robotic device proved successful in the whole range of colorectal operations and a reliable assistant. No problems specific to the device were encountered.

CONCLUSIONS

The EndoAssist robot is a useful laparoscopic assistant and aided in the introduction of laparoscopic colorectal surgery.  相似文献   
982.
983.

Objectives

The aim of the study was to explore the awareness of rectal microbicides, the use of pre‐exposure prophylaxis (PREP) and the willingness to participate in biomedical HIV prevention trials in a cohort of HIV‐negative gay men.

Methods

In a community‐based cohort study, HIV‐negative homosexually active men in Sydney, Australia were questioned about awareness of rectal microbicides, use of PREP, and willingness to participate in trials of such products. Predictors of awareness and willingness to participate were analysed by logistic regression. Use of PREP was examined prospectively.

Results

Overall, 14% had heard of rectal microbicides. Older (P=0.05) and university‐educated men (P=0.001) were more likely to have knowledge of rectal microbicides. Almost one‐quarter (24%) of men reported that they were likely/very likely to participate in rectal microbicide trials. Among those men with definite opinions on participation, awareness of rectal microbicides was significantly associated with unwillingness to participate [odds ratio (OR) 0.78, 95% confidence interval (CI) 0.65–0.93, P=0.007]. Willingness to participate in trials using antiretroviral drugs (ARVs) to prevent HIV infection was reported by 43% of men, and was higher among those who reported unprotected anal intercourse (UAI) with HIV‐positive partners (OR 1.88, 95% CI 0.99–3.56). There was no evidence of current PREP use.

Conclusions

This study demonstrates that Australian gay men have had little experience with PREP use and rectal microbicides. About half would be willing to consider participation in trials using ARVs to prevent HIV infection. Extensive community education and consultation would be required before PREP or rectal microbicides could be trialled in populations of gay Australian men.
  相似文献   
984.

Objectives

Efavirenz‐based HIV therapy is associated with breast hypertrophy and gynaecomastia. Here, we tested the hypothesis that efavirenz induces gynaecomastia through direct binding and modulation of the oestrogen receptor (ER).

Methods

To determine the effect of efavirenz on growth, the oestrogen‐dependent, ER‐positive breast cancer cell lines MCF‐7, T47D and ZR‐75‐1 were treated with efavirenz under oestrogen‐free conditions in the presence or absence of the anti‐oestrogen ICI 182,780. Cells treated with 17β‐oestradiol in the absence or presence of ICI 182,780 served as positive and negative controls, respectively. Cellular growth was assayed using the crystal violet staining method and an in vitro receptor binding assay was used to measure the ER binding affinity of efavirenz.

Results

Efavirenz induced growth in MCF‐7 cells with an estimated effective concentration for half‐maximal growth (EC50) of 15.7 μM. This growth was reversed by ICI 182,780. Further, efavirenz binds directly to the ER [inhibitory concentration for half maximal binding (IC50) of ~52 μM] at a roughly 1000‐fold higher concentration than observed with 17β‐oestradiol.

Conclusions

Our data suggest that efavirenz‐induced gynaecomastia may be caused, at least in part, by drug‐induced ER activation in breast tissues.  相似文献   
985.
986.

Background

In rehabilitation, training intensity is usually adapted to optimize the trained system to attain better performance (overload principle). However, in balance rehabilitation, the level of intensity required during training exercises to optimize improvement in balance has rarely been studied, probably due to the difficulty in quantifying the stability level during these exercises. The goal of the present study was to test whether the stabilizing/destabilizing forces model could be used to analyze how stability is challenged during several exergames, that are more and more used in balance rehabilitation, and a dynamic functional task, such as gait.

Methods

Seven healthy older adults were evaluated with three-dimensional motion analysis during gait at natural and fast speed, and during three balance exergames (50/50 Challenge, Ski Slalom and Soccer). Mean and extreme values for stabilizing force, destabilizing force and the ratio of the two forces (stability index) were computed from kinematic and kinetic data to determine the mean and least level of dynamic, postural and overall balance stability, respectively.

Results

Mean postural stability was lower (lower mean destabilizing force) during the 50/50 Challenge game than during all the other tasks, but peak postural instability moments were less challenging during this game than during any of the other tasks, as shown by the minimum destabilizing force values. Dynamic stability was progressively more challenged (higher mean and maximum stabilizing force) from the 50/50 Challenge to the Soccer and Slalom games, to the natural gait speed task and to the fast gait speed task, increasing the overall stability difficulty (mean and minimum stability index) in the same manner.

Conclusions

The stabilizing/destabilizing forces model can be used to rate the level of balance requirements during different tasks such as gait or exergames. The results of our study showed that postural stability did not differ much between the evaluated tasks (except for the 50/50 Challenge), compared to dynamic stability, which was significantly less challenged during the games than during the functional tasks. Games with greater centre of mass displacements and changes in the base of support are likely to stimulate balance control enough to see improvements in balance during dynamic functional tasks, and could be tested in pathological populations with the approach used here.  相似文献   
987.
Cytokines are major immune system regulators. Previously, innate cytokine profiles determined by lipopolysaccharide stimulation were shown to be highly heritable. To identify regulating genes in innate immunity, we analyzed data from a genome-wide linkage scan using microsatellites in osteoarthritis (OA) patients (The GARP study) and their innate cytokine data on interleukin (IL)-1β, IL-1Ra, IL-10 and tumor necrosis factor (TNF)α. A confirmation cohort consisted of the Leiden 85-Plus study. In this study, a linkage analysis was followed by manual selection of candidate genes in linkage regions showing LOD scores over 2.5. An single-nucleotide polymorphism (SNP) gene tagging method was applied to select SNPs on the basis of the highest level of gene tagging and possible functional effects. QTDT was used to identify the SNPs associated with innate cytokine production. Initial association signals were modeled by a linear mixed model. Through these analyses, we identified 10 putative genes involved in the regulation of TNFα. SNP rs6679497 in gene CD53 showed significant association with TNFα levels (P=0.001). No association of this SNP was observed with OA. A novel gene involved in the innate immune response of TNFα is identified. Genetic variation in this gene may have a role in diseases and disorders in which TNFα is closely involved.  相似文献   
988.
Acute hyperglycaemia has been associated with complications, prolonged intensive care unit and hospital stay, and increased mortality. We made an inventory of the prevalence and prognostic value of hyperglycaemia, and of the effects of glucose control in different groups of critically ill patients. The prevalence of hyperglycaemia in critically ill patients, using stringent criteria, approaches 100%. An unambiguous negative correlation between hyperglycaemia and mortality has been described in various groups of critically ill patients. Although the available evidence remains inconsistent, there appears to be a favourable effect of glucose regulation. This effect on morbidity and mortality depends on patient characteristics. To be able to compare results of future studies involving glucose regulation, better definitions of hyperglycaemia (and consequently of normoglycaemia) and patient populations are needed.  相似文献   
989.

Background  

The purpose of this study was to compare the expression and the prognostic effect of the breast cancer stem cell marker aldehyde dehydrogenase-1 (ALDH1) in young and elderly breast cancer patients.  相似文献   
990.
Background: Inhaled nitric oxide (iNO), commonly used for hypoxic neonates, may react with haemoglobin to form methaemoglobin (MetHb). MetHb monitoring during iNO therapy has been questioned since low doses of iNO are used. Aim: To evaluate the incidence of and identify risk factors associated with elevated MetHb in neonates treated with iNO. Methods: Neonates who were treated with iNO and had at least one MetHb measurement were included. Demographic characteristics and methods of iNO administration (dosage, duration) at the time of each MetHb measurement were analysed. Results: Four hundred and fifty‐two MetHb measurements from 81 premature and 82 term and near‐term infants were analysed. MetHb was above 5% in one‐term infant, and between 2.5–5% in 16 infants. A higher maximum dose of iNO (22.7 vs 17.7 p.p.m.), but not gestational age, was a significant risk factor for elevated MetHb. Significantly higher oxygen levels (75.5% vs 51.7%) were associated with higher MetHb in term infants. Preterm infants had no risk for high MetHb when iNO was kept below 8 p.p.m. These data suggest the possibility of limiting blood withdrawal when low doses iNO are used. Conclusion: High MetHb is exceptional in neonates treated with low dose iNO. Associated risk factors are related to high iNO dose and the simultaneous use of high concentrations of oxygen.  相似文献   
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