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1.
Fate of micelles and quantum dots in cells.   总被引:2,自引:0,他引:2  
Micelles and quantum dots have been used as experimental drug delivery systems and imaging tools both in vitro and in vivo. Investigations of their fate at the subcellular level require different surface-core modifications. Among the most common modifications are those with fluorescent probes, dense-core metals or radionucleids. Cellular fate of several fluorescent probes incorporated into poly(caprolactone)-b-copolymer micelles (PCL-b-PEO) was followed by confocal microscopy, and colloidal gold incorporated in poly 4-vinyl pyridine-PEO micelles were developed to explore micelle fate by electron microscopy. More recently, we have examined quantum dots (QDs) as the next-generation-labels for cells and nanoparticulate drug carriers amenable both to confocal and electron microscopic analyses. Effects of QDs at the cellular and subcellular levels and their integrity were studied. Results from different studies suggest that size, charge and surface manipulations of QDs may play a role in their subcellular distribution. Examples of pharmacological agents incorporated into block copolymer micelles, administered or attached to QD surfaces show how the final biological outcome (e.g. cell death, proliferation or differentiation) depends on physical properties of these nanoparticles.  相似文献   
2.
A case of an unusual lesion from the maxilla is presented. Macroscopically, the lesion was solid and histologically consisted of 'multiple separate keratocysts' of varying size that infiltrated into the surrounding bone and soft tissues. Panoramic image and CT scans showed a multilocular honeycomb ill-defined radiolucency with infiltration into the maxillary sinus and floor of orbit. This lesion should be differentiated from similar odontogenic lesions, such as keratoameloblastoma and papilliferous keratoameloblastoma. As there was no evidence of follicles, islands of ameloblastoma, or papilliferous structures in the entire specimen, the lesion could not be diagnosed as either a keratoameloblastoma or a papilliferous keratoameloblastoma. The invasive and destructive growth behavior, the histopathological features, and the histochemical pattern of the collagen stroma imply that this solid lesion is a neoplasia. It is suggested that the proper term for this lesion is solid variant of odontogenic keratocyst.  相似文献   
3.
There has been a large amount of work done recently on small peripheral stage I adenocarcinomas that come to resection. Radiological (including proportion of ground glass opacity) and pathological features of these lesions (predominant bronchioloalveolar component, central scar with or without invasion <0.5 cm) have been shown to be prognostically favorable with cure rate approaching 100% in some series. Most of these studies emanate from Japan. The relevance of these studies to other parts of the world, particularly North America, is discussed in light of the fact that some recent chemotherapeutic studies with gefitinib have shown increased response in individuals of Asian origin, suggesting that some genetic differences may be significant. The relevance of these findings to pathologists and the pathological study of small peripheral adenocarcinomas from elsewhere in the world are discussed.  相似文献   
4.
Genetic alterations leading to overactivation of mammalian target of rapamycin (mTOR) signaling result in brain overgrowth syndromes such as focal cortical dysplasia (FCD) and megalencephaly. Megalencephaly with cutis tri‐color of the Blaschko‐linear type pigmentary mosaicism and intellectual disability is a rare neurodevelopmental disorder attributed to the recurrent mosaic c.5930C > T (p.Thr1977Ile) MTOR variant. This variant was previously reported at low to intermediate levels of mosaicism in the peripheral blood of three unrelated individuals with consistent clinical findings. We report a fourth case of a 3‐year‐old female presenting with megalencephaly, obstructive hydrocephalus due to cerebral aqueductal stenosis, asymmetric polymicrogyria, dysgenesis of the corpus callosum, hypotonia, developmental delay, and cutaneous pigmentary mosaicism. Oligonucleotide and SNP chromosomal microarray (CMA), karyotype, and trio whole exome sequencing (WES) in the peripheral blood, as well as a targeted gene variant panel from fibroblasts derived from hyperpigmented and non‐hyperpigmented skin did not detect any abnormalities in MTOR or other genes associated with brain overgrowth syndromes. Unlike the previously reported cases, the de novo c.5930C > T (p.Thr1977Ile) MTOR variant was detected at 32% mosaicism in our patient only after WES was performed on fibroblast‐derived DNA from the hyperpigmented skin. This case demonstrates the tissue variability in mosaic expression of the recurrent p.Thr1977Ile MTOR variant, emphasizes the need for skin biopsies in the genetic evaluation of patients with skin pigmentary mosaicism, and expands the clinical phenotype associated with this pathogenic MTOR variant.  相似文献   
5.
Purpose: There is a common opinion that spinal fractures usually reflect the substantial impact of injuries and therefore may be used as a marker of significant associated injuries, specifically for intraabdominal injury (IAI). The impact of concomitant spinal cord injury (SCI) with the risk of associated IAI has not been well clarified. The aim of this study was to evaluate the incidence and severity of IAIs in patients suffering from spinal fractures with or without SCI. Methods: A retrospective cohort study using the Israeli National Trauma Registry was conducted. Patients with thoracic, lumbar and thoracolumbar fractures resulting from blunt mechanisms of injury from January 1, 1997 to December 31, 2018 were examined, comparing the incidence, severity and mortality of IAIs in patients with or without SCI. The collected variables included age, gender, mechanism of injury, incidence and severity of the concomitant IAIs and pelvic fractures, abbreviated injury scale, injury severity score, and mortality. Statistical analysis was performed using GraphPad InStat ® Version 3.10, with Chi-square test for independence and two sided Fisher’s exact probability test. Results: Review of the Israeli National Trauma Database revealed a total of 16,878 patients with spinal fractures. Combined thoracic and lumbar fractures were observed in 1272 patients (7.5%), isolated thoracic fractures in 4967 patients (29.4%) and isolated lumbar fractures in 10,639 patients (63.0%). The incidence of concomitant SCI was found in 4.95% (63/1272), 7.65% (380/4967) and 2.50% (266/10639) of these patients, respectively. The overall mortality was 2.5%, proving higher among isolated thoracic fracture patient than among isolated lumbar fracture counterparts (11.3% vs. 4.6%, p < 0.001). Isolated thoracic fractures with SCI were significantly more likely to die than non-SCI counterparts (8.2% vs. 3.1%, p < 0.001). There were no differences in the incidence of IAIs between patients with or without SCI following thoracolumbar fractures overall or in isolated thoracic fractures; although isolated lumbar fractures patients with SCI were more likely to have renal (3.4% vs. 1.6%, p = 0.02) or bowel injuries (2.3% vs. 1.0%, p = 0.04) than the non-SCI counterparts. Conclusion: SCI in the setting of thoracolumbar fracture does not appear to be a marker for associated IAI. However, in a subset of isolated lumbar fractures, SCI patient is associated with increased risks for renal and bowel injury.  相似文献   
6.
Wound‐dressing performances are affected by exudate viscosity, resistance to flow because of gravity, and bodyweight loads, the level of which is related to the body position. Here, we focussed on two dressing properties: (a) Sorptivity—the ability of dressings to transfer exudate away from the wound bed by capillary action—and (b) Durability—the capacity of dressings to maintain their integrity over time and during their removal. Both properties are critically important for avoiding further tissue damage but require the development of new laboratory tests for their measurement. A computer‐controlled phantom of an exuding sacral pressure ulcer has therefore been developed and used to compare the performances of Exufiber (Mölnlycke Health Care) vs an alternative market‐leading dressing. Sorptivity was determined using weight tests, and durability was measured through tensile tests of the used dressings. For a supine configuration, the Exufiber dressing demonstrated ~three times higher sorptivity and better durability, withstanding ~five times greater strain energy than the other product before failure occurred. This work paves the way for quantitative, standardised testing of dressings in all aspects of exudate management. The reported tests are further suitable for testing dressing combinations or how dressings interact with negative pressure wound therapy.  相似文献   
7.
8.
血糖浓度增高对急性心肌梗塞预后的影响   总被引:1,自引:0,他引:1  
目的:回顾性地了解无论是否伴有糖尿病,血糖浓度增高对急性心肌梗塞住院病死率及心梗后心衰、心源性休克的影响。方法:1990年1月~2000年10月我院心肌梗塞住院病人100例,将入院时血糖浓度<6.6mmol/L作为A组。入院时血糖浓度增高在6.6~11.1mmol/L为B组。入院时血糖浓度>11.1mmol/L为C组,分别计算各组发生心衰、心源性休克的百分率及住院病死率。结果:A组心衰发生率10.71%,心源性休克发生率3.57%,住院病死率3.57%;B组心衰发生率41.18%,心源性休克发生率29.41%,住院病死率26.47%;C组心衰发生率52.63%,心源性休克发生率31.58%,住院病死率26.32%。B组、C组心衰发生率、心源性休克发生率及住院病死率比A组明显增加,差异有显著性。而B组与C组心衰发生率、心源性休克发生率及住院病死率无显著性差异。结论:血糖浓度增高,心衰、心源性休克发生率及住院病死率明显增高。  相似文献   
9.
10.
PURPOSE: Loss or abnormal expression of Cyclin D2, a crucial cell cycle-regulatory gene, has been described in human cancers; however, data for prostate tumors are lacking. We investigated the epigenetic silencing of Cyclin D2 gene in prostate cancers and correlated the data with clinicopathological features. EXPERIMENTAL DESIGN: Cyclin D2 promoter methylation was analyzed in 101 prostate cancer samples by methylation-specific PCR. In addition, we analyzed 32 nonmalignant prostate tissue samples, which included 24 samples of benign disease, benign prostatic hypertrophy, or prostatitis and 7 normal tissues adjacent to cancer. The methylation status of Cyclin D2 was correlated with the methylation of nine other tumor suppressor genes published previously from our laboratory on the same set of samples (R. Maruyama et al., Clin. Cancer Res., 8: 514-519, 2002). The methylation index was determined as a reflection of the methylated fraction of the genes examined. RESULTS: The frequency of methylation of Cyclin D2 promoter was significantly higher in prostate cancers (32%) than in nonmalignant prostate tissues (6%; P = 0.004), and it was not age related. Aberrant methylation was present at insignificant levels in peripheral blood lymphocytes (8%). We also compared methylation of cyclin D2 with methylation of nine tumor suppressor genes [published previously from our laboratory (R. Maruyama et al., Clin. Cancer Res., 8: 514-519, 2002)] studied in the same set of samples. The concordances between methylation of Cyclin D2 and the methylation of RARbeta, GSTP1, CDH13, RASSF1A, and APC were statistically significant, whereas methylation of P16, DAPK, FHIT, and CDH1 were not significant. The differences in methylation index between malignant and nonmalignant tissues for all 10 genes were statistically significant (P < 0.0001). Among clinicopathological correlations, the high Gleason score group had significantly greater methylation frequency of Cyclin D2 (42%; P = 0.004). Although the high preoperative serum prostate-specific antigen (PSA) group did not have significantly greater methylation frequency, methylation of Cyclin D2 had higher mean PSA value. Also, the prostate cancers in the high Gleason score group had high mean values of PSA. CONCLUSIONS: Our results indicate that methylation of Cyclin D2 in prostate cancers correlates with clinicopathological features of poor prognosis. These findings are of biological and potential clinical importance.  相似文献   
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