首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   165篇
  免费   11篇
  国内免费   2篇
基础医学   33篇
口腔科学   1篇
临床医学   15篇
内科学   38篇
皮肤病学   1篇
神经病学   1篇
特种医学   12篇
外科学   32篇
综合类   2篇
预防医学   6篇
眼科学   5篇
药学   30篇
肿瘤学   2篇
  2023年   5篇
  2022年   2篇
  2021年   15篇
  2020年   3篇
  2019年   3篇
  2018年   2篇
  2017年   2篇
  2016年   4篇
  2015年   4篇
  2014年   9篇
  2013年   8篇
  2012年   9篇
  2011年   12篇
  2010年   12篇
  2009年   11篇
  2008年   4篇
  2007年   14篇
  2006年   9篇
  2005年   14篇
  2004年   18篇
  2003年   2篇
  2002年   1篇
  2001年   1篇
  2000年   1篇
  1999年   1篇
  1995年   2篇
  1992年   1篇
  1989年   1篇
  1988年   2篇
  1974年   1篇
  1971年   2篇
  1969年   2篇
  1965年   1篇
排序方式: 共有178条查询结果,搜索用时 15 毫秒
1.
Although mucoepidermoid carcinoma is the most common primary malignancy of the salivary glands, the sclerosing morphologic variant of this tumor is extremely rare, with only 6 reported cases. As its name suggests, sclerosing mucoepidermoid carcinoma is characterized by an intense central sclerosis that occupies the entirety of an otherwise typical tumor, frequently with an inflammatory infiltrate of plasma cells, eosinophils, and/or lymphocytes at its peripheral regions. The sclerosis associated with these tumors may obscure their typical morphologic features and result in diagnostic difficulties. Tumor infarction and extravasation of mucin eventuating in reactive fibrosis are 2 mechanisms of formation that have been suggested as underlying this morphologic variant. We describe herein another case of sclerosing mucoepidermoid carcinoma that was diagnosed in a 44-year-old woman and review the relevant literature. Morphologic evidence in support of the mucin extravasation hypothesis was identified, as small pools of mucin were present throughout the tumor. However, there was no concentration of the mucin pools near the areas with the most viable tumor cells, which would have provided evidence for a temporal sequence that eventuates in lack of mucin in the most sclerotic regions.  相似文献   
2.
Specimen misidentification is a common cause of errors in surgical pathology. We report a case where bone-marrow biopsies from patients of different genders were mislabeled and molecular methods were applied to resolve the identity. A short tandem repeat (STR)-polymerase chain reaction-based assay, commonly used in paternity testing, was employed in an attempt to assign the correct identity to the specimens. However, the specimens had been processed by decalcification and the DNA yield was poor. One of the markers in the assay is the non-STR amelogenin locus that distinguishes the X and Y chromosomes. This amelogenin marker results in a product of low molecular weight, enabling unequivocal resolution of identity despite a poor DNA yield. The prevalence of errors in pathology due to specimen misidentifications is reviewed.  相似文献   
3.
Dissipation kinetics of chlorantraniliprole was studied in sandy loam soils of sugarcane ecosystem by adopting a rapid analytical method. The recovery of chlorantraniliprole was 91.67 % when extracted with ethyl acetate as against only 65.58 % in acetonitrile-based extraction. An additional cleanup step with primary secondary amine did not enhance the recovery significantly over the no-cleanup method. The ethyl acetate-based extraction followed by direct quantification in HPLC (High-performance liquid chromatography) without any cleanup facilitated rapid quantification of chlorantraniliprole residues. The LOQ (limit of quantification) of the method was 0.01 μg/g. The half-life of chlorantraniliprole was 6.50 and 6.81 days for the recommended and double the recommended doses, respectively.  相似文献   
4.
5.

Context

Non–muscle-invasive bladder cancer (NMIBC) is associated with a high recurrence risk, partly because of the persistence of lesions following transurethral resection of bladder tumour (TURBT) due to the presence of multiple lesions and the difficulty in identifying the exact extent and location of tumours using standard white-light cystoscopy (WLC). Hexaminolevulinate (HAL) is an optical-imaging agent used with blue-light cystoscopy (BLC) in NMIBC diagnosis. Increasing evidence from long-term follow-up confirms the benefits of BLC over WLC in terms of increased detection and reduced recurrence rates.

Objective

To provide updated expert guidance on the optimal use of HAL-guided cystoscopy in clinical practice to improve management of patients with NMIBC, based on a review of the most recent data on clinical and cost effectiveness and expert input.

Evidence acquisition

PubMed and conference searches, supplemented by personal experience.

Evidence synthesis

Based on published data, it is recommended that BLC be used for all patients at initial TURBT to increase lesion detection and improve resection quality, thereby reducing recurrence and improving outcomes for patients. BLC is particularly useful in patients with abnormal urine cytology but no evidence of lesions on WLC, as it can detect carcinoma in situ that is difficult to visualise on WLC. In addition, personal experience of the authors indicates that HAL-guided BLC can be used as part of routine inpatient cystoscopic assessment following initial TURBT to confirm the efficacy of treatment and to identify any previously missed or recurrent tumours. Health economic modelling indicates that the use of HAL to assist primary TURBT is no more expensive than WLC alone and will result in improved quality-adjusted life-years and reduced costs over time.

Conclusions

HAL-guided BLC is a clinically effective and cost-effective tool for improving NMIBC detection and management, thereby reducing the burden of disease for patients and the health care system.

Patient summary

Blue-light cystoscopy (BLC) helps the urologist identify bladder tumours that may be difficult to see using standard white-light cystoscopy (WLC). As a result, the amount of tumour that is surgically removed is increased, and the risk of tumour recurrence is reduced. Although use of BLC means that the initial operation costs more than it would if only WLC were used, over time the total costs of managing bladder cancer are reduced because patients do not need as many additional operations for recurrent tumours.  相似文献   
6.
Although tremendous progress has been made in conventional treatment for ischemic heart disease, it still remains a major cause of death and disability. Cell-based therapeutics holds an exciting frontier of research for complete cardiac recuperation. The capacity of diverse stem and progenitor cells to stimulate cardiac renewal has been analysed, with promising results in both pre-clinical and clinical trials. Mesenchymal stem cells have been ascertained to have regenerative ability via a variety of mechanisms, including differentiation from the mesoderm lineage, immunomodulatory properties, and paracrine effects. Also, their availability, maintenance, and ability to replenish endogenous stem cell niches have rendered them suitable for front-line research. This review schemes to outline the use of mesenchymal stem cell therapeutics for ischemic heart disease, their characteristics, the potent mechanisms of mesenchymal stem cell-based heart regeneration, and highlight preclinical data. Additionally, we discuss the results of the clinical trials to date as well as ongoing clinical trials on ischemic heart disease.  相似文献   
7.
In a simple, one-step reaction, we have synthesized a pyridoxal-based chemosensor by reacting tris(hydroxymethyl)aminomethane (TRIS) together with pyridoxal hydrochloride to yield a Schiff-base ligand that is highly selective for the detection of Zn(ii) ion. Both the ligand and the Zn(ii) complex have been characterized by 1H & 13C NMR, ESI-MS, CHN analyses, and X-ray crystallography. The optical properties of the synthesized ligand were investigated in an aqueous buffer solution and found to be highly selective and sensitive toward Zn(ii) ion through a fluorescence turn-on response. The competition studies reveal the response for zinc ion is unaffected by all alkali and alkaline earth metals; and suppressed by Cu(ii) ion. The ligand itself shows a weak fluorescence intensity (quantum yield, Φ = 0.04), and the addition of zinc ion enhanced the fluorescence intensity 12-fold (quantum yield, Φ = 0.48). The detection limit for zinc ion was 2.77 × 10−8 M, which is significantly lower than the WHO''s guideline (76.5 μM). Addition of EDTA to a solution containing the ligand–Zn(ii) complex quenched the fluorescence, indicating the reversibility of Zn(ii) binding. Stoichiometric studies indicated the formation of a 2 : 1 L2Zn complex with a binding constant of 1.2 × 109 M−2 (±25%). The crystal structure of the zinc complex shows the same hydrated L2Zn complex, with Zn(ii) ion binding with an octahedral coordination geometry. We also synthesized the copper(ii) complex of the ligand, and the crystal structure showed the formation of a 1 : 1 adduct, revealing 1-dimensional polymeric networks with octahedral coordinated Cu(ii). The ligand was employed as a sensor to detect zinc ion in HEK293 cell lines derived from human embryonic kidney cells grown in tissue culture which showed strong luminescence in the presence of Zn(ii). We believe that the outstanding turn-on response, sensitivity, selectivity, lower detection limit, and reversibility toward zinc ion will find further application in chemical and biological science.

The synthesis, characterization, X-ray crystallography, and live-cell imaging of pyridoxal-TRIS Schiff-base ligand which is selective as a luminescence sensor to detect Zn(ii) ion, and the corresponding Zn(ii) and Cu(ii) complexes are described.  相似文献   
8.
Indoleamine 2,3-dioxygenase 1 (IDO1) has been identified as a target for small-molecule immunotherapy for the treatment of a variety of cancers including renal cell carcinoma and metastatic melanoma. This work focuses on the identification of IDO1 inhibitors containing replacements or isosteres for the amide found in BMS-986205, an amide-containing, IDO1-selective inhibitor currently in phase III clinical trials. Detailed subsequently are efforts to identify a structurally differentiated IDO1 inhibitor via the pursuit of a variety of heterocyclic isosteres, leading to the discovery of highly potent, imidazopyridine-containing IDO1 inhibitors.  相似文献   
9.
The plant Kaempferia rotunda Linn. has been explored for its anti oxidant potential in the present study. The antioxidant property was assessed by lipid peroxidation markers such as malonaldehyde (MDA) and 4-hydroxyl-2-nonenal (4-HNE). The lipid peroxidation byproducts are highly toxic and responsible for various diseases like myocardial infarction, diabetes mellitus, hepatic injury, atherosclerosis, rheumatoid arthritis and cancer. The chemical constituents of the plant were critically and qualitatively analyzed to confirm the presence of flavonoids and phenolic derivatives. Hence our objective has been designed to evaluate the antioxidant effect of Kaempferia rotunda linn. and its contribution to control the lipid peroxidation.  相似文献   
10.
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号