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Recent evidence from structural priming studies suggests that children with specific language impairment (SLI) are more likely to produce verb morphemes such as auxiliary is when their previous sentence contained an auxiliary than when it did not. The same paradigm was employed in the present study to determine whether failures to include auxiliary is might be due to prior use of nonfinite sentences (e.g., The mouse eating the cheese). Preschoolers with SLI and a group of younger normally developing children were more likely to produce auxiliary is to describe target pictures when the preceding sentence contained auxiliary are than when it contained past tense. Use of is in the target sentence was least likely when the preceding sentence was nonfinite. The implications of these findings for current accounts of SLI and current models of sentence production are discussed.  相似文献   
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The association between gastroesophageal reflux (GER) and intestinal malrotation (IM) has been well described. Delayed or impaired gastric emptying in IM is thought to be a contributing factor in the development of gastroesophageal reflux disease (GERD). The current study assessed the role of malrotation in delayed gastric emptying in children with GERD. We also evaluated the interactions between GERD, malrotation, gastric pH abnormalities, and gastric dysmotility. Sixty-seven patients between 1 and 5 years of age (mean 3.08±1.2) and with symptoms of GER, such as emesis, reactive or recurrent lung disease, and/or growth retardation, were studied in 2001–2005. Upper and lower gastrointestinal contrast studies were performed for the diagnosis of malrotation. Gastric motility was evaluated with a liquid gastric emptying protocol. GER was documented by upper gastrointestinal studies, scintigraphy, and/or 24-h pH monitoring. In our series of 44 children with GERD, there was an unexpectedly high incidence of IM: 54.5% (24/44). IM has previously been known to occur in 25% of patients with GERD. GERD was found in 24 (82.7%) of 29 patients with IM. Mean nuclear gastric emptying (MNGE) was 51.6±8.04 min in patients with isolated GERD and 96.6±20.5 min in children with IM and GERD. There was a statistically significant difference in MNGE time (p<0.05) between children with primary GERD and in those with GERD and IM. Esophageal pH monitoring showed that mean fraction time below pH 4 was 7.06±1.1% in patients with isolated GERD and 14.7±4.1% in patients with IM and GERD. GERD is common in children between 1 and 5 years old. Using gastric emptying studies and esophageal pH monitoring, we have shown that gastric dysmotility and esophageal pH abnormalities are highly prevalent, especially in children with malrotation compared with children with isolated GERD. These findings suggest that malrotation is an important factor responsible for delayed gastric emptying in GERD. Hence, we recommend that all infants and children with GERD and delayed gastric emptying undergo careful evaluation for malrotation.  相似文献   
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A monoclonal thyroid-stimulating antibody   总被引:5,自引:0,他引:5       下载免费PDF全文
The thyrotropin receptor, also known as the thyroid-stimulating hormone receptor (TSHR), is the primary antigen of Graves disease. Stimulating TSHR antibodies are the cause of thyroid overstimulation and were originally called long-acting thyroid stimulators due to their prolonged action. Here we report the successful cloning and characterization of a monoclonal antibody (MS-1) with TSHR-stimulating activity. The thyroid-stimulating activity of MS-1 was evident at IgG concentrations as low as 20 ng/ml. MS-1 also competed for radiolabeled TSH binding to the native TSHR and was able to compete for TSH-induced stimulation. MS-1 recognized a conformational epitope within the TSHR alpha (or A) subunit but excluding the receptor cleavage region. Using an assay measuring loss of antibody recognition after cleavage we demonstrated that MS-1, in contrast to TSH, was unable to enhance TSHR posttranslational cleavage. Since receptor cleavage is followed by alpha subunit shedding and receptor degradation, the functional half-life of the receptor may be extended. The isolation and characterization of MS-1 provides a novel explanation for the prolonged thyroid stimulation in this disease which may be secondary to the lack of receptor cleavage in addition to the prolonged half-life of IgG itself.  相似文献   
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Popliteal artery injuries: the Kashmir experience   总被引:7,自引:0,他引:7  
BACKGROUND: Popliteal artery injuries pose a serious threat to limb survival. Blunt trauma appears to be associated with a higher amputation rate than penetrating trauma, probably because of the more extensive nature of the injuries. METHODS: Two hundred seventy-two cases of popliteal artery injury were studied retrospectively from 1989 to 2001, a warlike period in Kashmir. Preoperative angiography was not performed. Thirty-two percent of patients had associated venous injury and 24.6% of patients had associated bone fracture. RESULTS: Overall morbidity was 55%, with the most common complication being infection (24%). Secondary amputation had to be performed in 16 patients (5.5%). The amputation rate was not influenced by cause of injury and type of repair or the presence of venous injury, but associated bone fracture significantly increased the risk of amputation (p < 0.05). The patients who underwent repair more than 12 hours after sustaining injury had a significantly greater amputation rate (p < 0.05). CONCLUSION: Prompt resuscitation, vascularization, and proper technique appear to be the only correctable factors that improve limb salvage.  相似文献   
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Diabetes has been classified mainly into types 1 and 2. Some type 2 diabetes patients, when developing ketosis, have been labeled as having atypical diabetes. Lately, syndromes of ketosis-prone diabetes, primarily in patients who we previously classified as type 2 diabetics, have emerged, and calls are being made to even reclassify diabetes. This mini-review will extensively deal with the historical, molecular, phenotypical, and clinical basis of why ketosis-prone diabetes is different than the traditional principles of type 1 and 2 diabetes and should be classified as such. Clinicians, especially those who are not diabetologists or endocrinologists, as well as hospitalists, intensivists, and primary care providers, will greatly benefit from this review.  相似文献   
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Abstract

At present, malignant tumours have become one of the most serious diseases that endanger human health. According to a survey on causes of death in Chinese population in early 1990s, the malignant tumours were the second leading cause of death. In the treatment of tumours, the ideal situation is that drugs should target and accumulate at tumour sites and destroy tumour cells specifically, without affecting normal cells and stem cells with regenerative capacity. This requires drugs to be specifically transported to the target organs, tissues, cells, and even specific organelles, like mitochondria, nuclei, lysosomes, endoplasmic reticulum (ER), and Golgi apparatus (GA). The nano drug delivery system can not only protect drugs from degradation but also facilitate functional modification and targeted drug delivery to the tumour site. This article mainly reviews the targeting of nano drug delivery systems to tumour cytoplasmic matrix, nucleus, mitochondria, ER, and lysosomes. Organelle-specific drug delivery system will be a major mean of targeting drug delivery with lower toxicity, less dosage and higher drug concentration in tumour cells.  相似文献   
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