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1.
Abstract: The evaluation of the Healthy Aboriginal Life Team's (HALT) petrol-sniffing prevention programs at Yuendumu, Kintore and the Pitjantjatjara Lands first required a specification of program outcome—which was not changes in the enumerated prevalence of petrol sniffing, but alteration in parental perceptions of the relevance and effectiveness of families' nurturant authority over recalcitrant youngsters. The evaluation then proceeded by a series of interviews with resident or ex-resident adults (Aboriginal and non-Aboriginal) of Yuendumu, Kintore, Kiwirrkurra, Ernabella, Indulkana and Fregon. Adults articulated their efficacy in different ways in each place. Some favoured the conclusion that HALT had helped them, others clearly identified HALT as an obstacle to or a distraction from the implementation of other preventive and curative community-based action. We discerned a ferment of cultural adjustment in the distribution of authority over children among parents and welfare agencies. We caution against finding in HALT'S successes a model procedure for benign interventions into such cultural adjustment.  相似文献   
2.
The induction by adenovirus-12 of a site-specific gap and assignment of the chimpanzee genes for thymidine kinase and galactokinase were studied by utilizing chimpanzee-mouse hybrid cells. It has been shown that adenovirus-12 induces a specific gap in the long arm of human chromosome 17 (HS 17); with chimpanzee-mouse hybrid cells the specific gap appears on the short arm of the chimpanzee homolog [PTR 19 (HS 17)] of HS 17. This result supports the proposed relationship of HS 17 to PTR 19 (HS 17) by means of a pericentric inversion. The chimpanzee thymidine kinase and galactokinase genes were assigned to PTR 19 (HS 17), further confirming the homology to HS 17. Other syntenic relationships and gene assignments were consistent with proposed homologies between chimpanzee and human chromosomes.  相似文献   
3.
4.
The testing of dried blood spots (DBSs) for human immunodeficiency type 1 (HIV-1) proviral DNA by PCR is a technology that has proven to be particularly valuable in diagnosing exposed infants. We implemented this technology for HIV-1 early infant diagnosis (EID) and HIV-1 RNA viral load determination in infants born of HIV-1-seropositive mothers from remote areas in Cameroon. The samples were collected between December 2007 and September 2010. Fourteen thousand seven hundred and sixty-three (14,763) DBS samples from infants born of HIV-positive mothers in 108 sites nationwide were tested for HIV. Of these, 1452 were positive on first PCR analyses (PCR1), giving an overall infection rate of 12.30%. We received only 475 DBS specimen for a second PCR testing (PCR2); out of these, 145 were positive. The median HIV-1 RNA viral load for 169 infant DBS samples tested was 6.85 log copies/ml, with values ranging from 3.37 to 8 log copies/ml. The determination of the viral load on the same DBS as that used for PCR1 allowed us to bypass the PCR2. The viral load values were high and tend to decrease with age but with a weak slope. The high values of viral load among these infants call for early and effective administration of antiretroviral therapy (ART). The findings from this study indicate that the use of DBS provides a powerful tool for perinatal screening programs, improvement on the testing algorithm, and follow-up during treatment, and thus should be scaled up to the entire nation.  相似文献   
5.

Background

The burden of traumatic and elective hip surgery is set to grow. With an increasing number of techniques and implants against the background of an aging population, the emphasis on evidence-based treatment has never been greater. The purpose of this study was to assess changes in the levels of evidence in the hip literature over a decade.

Materials and methods

Articles pertaining to hip surgery from the years 2000 and 2010 in Hip International, Journal of Arthroplasty, Journal of Bone and Joint Surgery and The Bone and Joint Journal were analysed. Articles were ranked by a five-point level of evidence scale and by type of study, according to guidelines from the Centre for Evidence-based Medicine.

Results

531 articles were analysed from 48 countries. The kappa value for the inter-observer reliability showed excellent agreement between the reviewers for study type (κ = 0.956, P < 0.01) and for levels of evidence (κ = 0.772, P < 0.01). Between 2000 and 2010, the overall percentage of high-level evidence (levels I and II) studies more than doubled (12 to 31 %, P < 0.001). The most frequent study type was therapeutic; the USA and UK were the largest producers of published work in these journals, with contributions from other countries increasing markedly over the decade.

Conclusions

There has been a significant increase in high levels of evidence in hip surgery over a decade (P < 0.001). We recommend that all orthopaedic journals consider implementing compulsory declaration by authors of the level of evidence to help enhance quality of evidence.

Level of evidence

Level 2: economic and decision analysis.
  相似文献   
6.

Objectives

The recovery of independent walking is an important goal in stroke rehabilitation. The objective of this systematic review was to identify all outcome measures used in the stroke research literature that included an evaluation of walking ability and evaluate the concepts contained in these measures with reference to the International Classification of Functioning, Disability and Health (ICF) framework.

Data sources

Searches were conducted of MEDLINE, CINAHL, EMBASE and PsycINFO databases for the time period January 1990-December 2005 using appropriate keywords.

Review methods

Studies were selected for further analysis if they used one or more standardized outcome measure incorporating an aspect of walking defined by the ICF. The outcome measure had to have published psychometric properties and specifically measure walking rather than mobility. The content of each outcome measure was classified with reference to the ICF subcategories for walking. The number of times each outcome measure was used was calculated.

Results

Three hundred and fifty-seven studies met the selection criteria. Sixty-one different outcome measures were used a total of 848 times to measure walking ability. Six of the outcome measures reflected impairment and 52 reflected limitations of activity and participation. The other three outcome measures showed overlap between domains, reflecting aspects of both impairment and limitations in activity and participation. The three most frequently used measures (self-paced gait speed measured over a short distance, spatiotemporal parameters and fast gait speed) were used 350 times but only assessed one ICF subcategory. The Rivermead Mobility Index and the Adapted Patient Evaluation Conference System assessed the greatest number of ICF subcategories but were used only 19 times and once respectively.

Conclusions

The most frequently used outcome measures reflect only one aspect of walking ability: walking short distances. Mobility tasks related to function in the community, like walking long distances, around obstacles and over uneven ground, and moving around outside or in buildings other then the home are not well represented by outcome measures used in most studies.  相似文献   
7.
8.
9.

Purpose

Design and synthesis of a tumor responsive nanoparticle-based system for imaging and treatment of various cancers.

Methods

Manganese oxide nanoparticles (Mn3O4 NPs) were synthesized and modified with LHRH targeting peptide or anti-melanoma antibodies (cancer targeting moieties) and a MMP2 cleavable peptide (a possible chemotactic factor). Nanostructured lipid carriers (NLCs) were used to entrap the BRAF inhibitor, vemurafenib, and enhance cytotoxicity of the drug. Size distribution, stability, drug entrapment, cytotoxicity and genotoxicity of synthesized nanoparticles were studied in vitro. Enhancement of MRI signal by nanoparticles and their body distribution were examined in vivo on mouse models of melanoma, ovarian and lung cancers.

Results

Uniform, stable cancer-targeted nanoparticles (PEGylated water-soluble Mn3O4 NPs and NLCs) were synthesized. No signs of cyto-,genotoxicity and DNA damage were detected for nanoparticles that do not contain an anticancer drug. Entrapment of vemurafenib into nanoparticles significantly enhanced drug toxicity in cancer cells with targeted V600E mutation. The developed nanoparticles containing LHRH and MMP2 peptides showed preferential accumulation in primary and metastatic tumors increasing the MRI signal in mice with melanoma, lung and ovarian cancers.

Conclusions

The proposed nanoparticle-based systems provide the foundation for building an integrated MRI diagnostic and therapeutic approach for various types of cancer.  相似文献   
10.

Background and purpose

Metal artifact reduction sequence (MARS) MRI and ultrasound scanning (USS) can both be used to detect pseudotumors, abductor muscle atrophy, and tendinous pathology in patients with painful metal-on-metal (MOM) hip arthroplasty. We wanted to determine the diagnostic test characteristics of USS using MARS MRI as a reference for detection of pseudotumors and muscle atrophy.

Patients and methods

We performed a prospective cohort study to compare MARS MRI and USS findings in 19 consecutive patients with unilateral MOM hips. Protocolized USS was performed by consultant musculoskeletal radiologists who were blinded regarding clinical details. Reports were independently compared with MARS MRI, the imaging gold standard, to calculate predictive values.

Results

The prevalence of pseudotumors on MARS MRI was 68% (95% CI: 43–87) and on USS it was 53% (CI: 29–76). The sensitivity of USS in detecting pseudotumors was 69% (CI 39–91) and the specificity was 83% (CI: 36–97). The sensitivity of detection of abductor muscle atrophy was 47% (CI: 24–71). In addition, joint effusion was detected in 10 cases by USS and none were seen by MARS MRI.

Interpretation

We found a poor agreement between USS and MARS MRI. USS was inferior to MARS MRI for detection of pseudotumors and muscle atrophy, but it was superior for detection of joint effusion and tendinous pathologies. MARS MRI is more advantageous than USS for practical reasons, including preoperative planning and longitudinal comparison.Approximately 1.5 million metal-on-metal (MOM) hip arthroplasties have been implanted worldwide since 1996 (FDA 2012). A high early failure rate for these prostheses has recently been demonstrated (Smith et al. 2012). The pattern of failure appears to differ from other hip arthroplasty types, with adverse reactions to wear-related metal debris being a prominent feature (Pandit et al. 2008, Kwon et al. 2011). These solid or cystic lesions have been termed pseudotumors (Pandit et al. 2008). A wide spectrum of adverse tissue reactions have been described. Histologically, using their pseudocapsules, these have been termed aseptic lymphocytic vasculitis-associated lesions (ALVALs) (Willert et al. 2005).Health regulatory guidelines recommend investigation with cross-sectional imaging, using either metal artifact reduction sequence (MARS) MRI or ultrasound scanning (USS), to evaluate the periprosthetic soft tissues. A number of advantages and disadvantages have been reported (Sabah et al. 2011, Liddle et al. 2013). The high-resolution capability of USS allows detailed imaging of solid or cystic extra-articular lesions and also detection of muscle atrophy (Sofka et al. 2004), joint effusions, gluteal tendon avulsion, and iliopsoas or trochanteric bursitis (Long et al. 2012). USS is also commonly used during guided anesthetic injection or fluid aspiration.

Table 1.

A comparison of the advantages and disadvantages of MARS MRI and ultrasound imaging of metal-on-metal hips
UltrasoundMARS MRI
1) Clinical evaluationNo metal artifact produced.
Operator-dependent; requires an experienced musculoskeletal sonographer.
Must be reported at the time of scanning.
Not operator dependant.
Can be reported later.
Images can be sent off-site for specialist opinion.
Useful during preoperative planning for revision arthroplasty (Hart et al. 2012).
 a) PseudotumorsExcellent at visualizing extra-articular fluid collections (including within the iliopsoas and trochanteric bursa).
Can differentiate easily between solid and fluid composition.
Deep posterior lesions and small lesions can often be missed (Nishii et al. 2012).
High sensitivity for the detection of solid and cystic soft tissue lesions including both small lesions and posterior lesions (Hart et al. 2012, Liddle et al. 2013).
 b) MusclesDual-view function can be used to simultaneously compare muscles on contralateral sides.
Currently not validated to assess muscle atrophy of the hip rotator cuff.
T1-weighted images excellent for assessment of the degree of muscle atrophy (Bal and Lowe 2008, Sabah et al. 2011).
Complete cross-sectional imaging allows easy comparison with the contralateral side.
Images can be accurately compared over time.
 c) Other pathologySensitive for joint effusion diagnosis (Foldes et al. 1992).
Can visualize the iliopsoas and gluteal tendons in detail.
Can be used to detect tendon avulsion of hip abductor muscles (Garcia et al. 2010).
Dynamic imaging is possible.
Hands-on examination can help localize pathology.
Sensitive modality for the assessment of gluteal tendon avulsion.
Other pathology can be identified, including metastatic disease, fractures, and muscle and bone marrow edema.
Metal artifact may obscure effusions and tendons directly adjacent to the implant.
2) Patient acceptabilitySafe, with no major contraindications (can be used on patients with cardiac pacemaker implants).
No problems with claustrophobia.
Non-invasive.
Invasive when used for guided fluid aspiration or injection.
Enclosed space often unacceptable to patients with claustrophobia.
Contraindicated in patients with incompatible metallic implants (e.g. a cardiac pacemaker).
3) GeneralRelatively low costs.
Compact equipment requires minimal space.
Often readily accessible in smaller healthcare trusts.
Relatively expensive.
The bulky equipment requires a relatively large space.
May not be accessible in smaller healthcare trusts.
Open in a separate windowThere is debate as to whether USS or MARS MRI should be used as the initial imaging modality for detection of pseudotumors around MOM hips. There have not been any published studies directly comparing the diagnostic performance of the 2 modalities, and guidelines leave the use of either investigation at the discretion of the surgeon.We determined the sensitivity, specificity, and predictive values of USS using MARS MRI as a reference for the detection of pseudotumors and muscle atrophy.  相似文献   
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