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11.
Emergency Radiology - The COVID-19 pandemic has affected healthcare systems and patients alike across the USA. We seek to elucidate changes in abdominal imaging ordered from the emergency...  相似文献   
12.
Antibacterial drug resistance is considered one of the biggest threats to human health worldwide, and the overuse of antibiotics accelerates this problem. Multidrug-resistant (MDR) bacteria are becoming harder to treat as the antibiotics used to treat them become less effective. Therefore, it is necessary to evaluate novel methods to control MDR bacteria. In this study, 40 bacterial isolates were collected from diabetic patients. The sensitivity of 40 bacterial isolates to seven antibiotics was evaluated. Four bacterial isolates were resistant to all antibiotic groups. The MDR pathogenic bacteria were selected and identified morphologically and biochemically and confirmed by VITEK® 2 system as follows: Staphylococcus aureus W35, Pseudomonas aeruginosa D31, Klebsiella pneumoniae DF30, and K. pneumoniae B40. Identification of the most resistant P. aeruginosa D31 was confirmed by the sequencing of a 16S ribosomal RNA gene with an accession number (MW241596). The inhibitory activity of eight types of native grown plant extracts against MDR bacteria was studied. Clove alcoholic extract (CAE) showed the highest inhibitory activity against MDR bacteria. Gas chromatography–mass spectrometry analysis of partially purified CAE at 0.9 Rf detected by thin-layer chromatography showed an active compound named hexadecenoic acid methyl ester with the highest antimicrobial effect against clinical pathogenic bacteria. The formation of silver nanoparticles (AgNPs) by CAE was studied. Evaluation of AgNPs was investigated by X-ray diffraction, UV–Vis, and transmission electron microscopy. The antibacterial effect of AgNPs after 2, 4, and 6 days in light and dark conditions was evaluated. Finally, the AgNPs synthesized using CAE possess good inhibition activity against the tested pathogenic bacteria. As a result, the bactericidal components listed above were promising in reducing MDR bacteria and can be used for treatments of bacterial infection and in the development of safe products with a natural base.  相似文献   
13.
14.
Using a combination of homozygosity mapping and whole‐exome sequencing (WES), we identified a novel missense c.1819G>A mutation (G607S) in the endothelin‐converting enzyme‐like 1 (ECEL1) gene in a consanguineous pedigree of Turkish origin presenting with a syndrome of camptodactyly, scoliosis, limited knee flexion, significant refractive errors and ophthalmoplegia. ECEL1 mutations were recently reported to cause recessive forms of distal arthrogryposis. This report expands on the molecular basis and the phenotypic spectrum of ECEL1‐associated congenital contracture syndromes.  相似文献   
15.

Background

The current research environment for academic surgeons demands that extramural funding be obtained. Financial support from the National Institutes of Health (NIH) is historically the gold standard for funding in the biomedical research community, with the R01 funding mechanism viewed as indicator of research independence. The NIH also supports a mentor-based career development mechanism (K-series awards) in order to support early-stage investigators. The goal of this study was to investigate the grants successfully awarded to pediatric surgeon-scientists and then determine the success of the K-series award recipients at achieving research independence.

Methods

In July 2012, all current members of the American Pediatric Surgery Association (APSA) were queried in the NIH database from 1988–2012 through the NIH Research Portfolio Online Reporting Tools. The following factors were analyzed: type of grant, institution, amount of funding, and funding institute or center.

Results

Among current APSA members, there have been 83 independent investigators receiving grants, representing 13% of the current APSA membership, with 171 independent grants funded through various mechanisms. Six percent currently have active NIH funding, with $7.2 million distributed in 2012. There have been 28 K-series grants awarded. Of the recipients of expired K08 awards, 39% recipients were subsequently awarded an R01 grant. A total of 63% of these K-awarded investigators transitioned to an independent NIH award mechanism.

Conclusions

Pediatric surgeon-scientists successfully compete for NIH funding. Our data suggest that although the K-series funding mechanism is not the only path to research independence, over half of the pediatric surgeons who receive a K-award are successful in the transition to independent investigator.  相似文献   
16.

Purpose

To compare the clinical, pathological and oncological outcome of EAML with classic angiomyolipoma (AML).

Methods

A retrospective review of patients’ files with a diagnosis of AML was conducted. Both classic and epithelioid AML were compared as regard the patients’ demographics, mode of presentation, tumor features and follow-up data. The accuracy of preoperative radiological diagnosis of EAML and the postoperative pathological data were evaluated.

Results

Between November 1988 and July 2012, 1,502 renal masses were treated. Forty-two patients (2.8 %) had renal AML of whom 12 patients (28.6 %) had epithelioid morphology. All the patients with EAML were symptomatic on presentation compared to 16.7 % asymptomatic patients with classic AML. Specific diagnosis of EAML was not suggested based on preoperative radiological evaluation. In one patient, there was a venous tumor extension into the right renal vein; another patient had a solitary pulmonary nodule. Pathological data of EAML patients showed wide areas of necrosis (4 patients), atypia (6 patients), increased mitotic figures (2 patients), nuclear anaplasia, enlarged nuclei and prominent nucleoli (3 patients), and multilobulated multinucleated giant cells (5 patients). At a median follow-up period of 12 and 9 months for EAML and classic AML groups, respectively, one patient with EAML had evidence of both local recurrence and distant metastasis 3 months following open radical nephrectomy.

Conclusion

Epithelioid AML is potentially aggressive and usually present as a symptomatic renal mass. It may be misdiagnosed as malignant renal mass on preoperative radiological evaluation.  相似文献   
17.
This study investigated the impact of catalase (Cat) overexpression in renal proximal tubule cells (RPTCs) on nuclear factor erythroid 2–related factor 2 (Nrf2) stimulation of angiotensinogen (Agt) gene expression and the development of hypertension and renal injury in diabetic Akita transgenic mice. Additionally, adult male mice were treated with the Nrf2 activator oltipraz with or without the inhibitor trigonelline. Rat RPTCs, stably transfected with plasmid containing either rat Agt or Nrf2 gene promoter, were also studied. Cat overexpression normalized systolic BP, attenuated renal injury, and inhibited RPTC Nrf2, Agt, and heme oxygenase-1 (HO-1) gene expression in Akita Cat transgenic mice compared with Akita mice. In vitro, high glucose level, hydrogen peroxide, and oltipraz stimulated Nrf2 and Agt gene expression; these changes were blocked by trigonelline, small interfering RNAs of Nrf2, antioxidants, or pharmacological inhibitors of nuclear factor-κB and p38 mitogen-activated protein kinase. The deletion of Nrf2-responsive elements in the rat Agt gene promoter abolished the stimulatory effect of oltipraz. Oltipraz administration also augmented Agt, HO-1, and Nrf2 gene expression in mouse RPTCs and was reversed by trigonelline. These data identify a novel mechanism, Nrf2-mediated stimulation of intrarenal Agt gene expression and activation of the renin-angiotensin system, by which hyperglycemia induces hypertension and renal injury in diabetic mice.  相似文献   
18.

Purpose

The purpose of this study was to characterize the growth rate of sacrococcygeal teratomas (SCTs) and determine its relationship to adverse outcomes.

Methods

A retrospective review of all pathology-confirmed isolated SCT patients evaluated with at least two documented ultrasounds and followed through hospital discharge between 2005 and 2012 was conducted. SCT growth rate was calculated as the difference between tumor volumes on a late- and early-gestation ultrasound divided by the difference in time. Outcomes were death, high-output cardiac failure (HOCF), hydrops, and preterm delivery. Student's t-test, receiver operator characteristics, Fisher's Exact test, and Pearson's correlation were performed.

Results

Of the 28 study subjects, there were 3 in utero demises and 2 neonatal deaths. Significantly faster SCT growth rates were seen in all adverse outcomes, including death (p < 0.0001), HOCF (p = 0.005), and preterm delivery (p = 0.009). There was a significant association with adverse outcomes at > 61 cm3/week (AUC = 0.87, p = 0.001, LR = 4.52). Furthermore, there was an even greater association with death at > 165 cm3/week (AUC = 0.93, p = 0.003, LR = 18.42). Growth rate was directly correlated with the percent of solid tumor (r = 0.60, p = 0.0008).

Conclusion

Faster SCT growth is associated with adverse outcomes. SCT growth rate determined by ultrasound is an effective prognostic indicator for adverse outcomes and easily applied to patient management.  相似文献   
19.
Portal vein thrombosis (PVT) was first reported in 1868 by Balfour and Stewart and is a medical condition in which the lumen of the portal vein is completely or partially obstructed due to the presence of a thrombus [1]. Inherited (Factor V Leiden and Prothrombin gene mutation G201210A, Protein C, S and Anti thrombin III deficiency) and acquired thrombophilias (Lupus Anticoagulant, myeloproliferative diseases, malignancy, surgery and trauma) account for majority of the cases of PVT.  相似文献   
20.
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