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141.
Prevalence and distribution of carcinoma in patients with solitary and multiple thyroid nodules on sonography 总被引:9,自引:0,他引:9
Frates MC Benson CB Doubilet PM Kunreuther E Contreras M Cibas ES Orcutt J Moore FD Larsen PR Marqusee E Alexander EK 《The Journal of clinical endocrinology and metabolism》2006,91(9):3411-3417
CONTEXT: Controversy remains as to the optimal management of patients with multiple thyroid nodules. OBJECTIVE: The objective of this study was to determine the prevalence, distribution, and sonographic features of thyroid cancer in patients with solitary and multiple thyroid nodules. DESIGN: We describe a retrospective observational cohort study that was carried out from 1995 to 2003. SETTING: The study was conducted in a tertiary care hospital. PATIENTS: Patients with one or more thyroid nodules larger than 10 mm in diameter who had ultrasound-guided fine needle aspiration (FNA) were included in the study. MAIN OUTCOME MEASURES: The main outcome measures were prevalence and distribution of thyroid cancer and the predictive value of demographic and sonographic features. RESULTS: A total of 1985 patients underwent FNA of 3483 nodules. The prevalence of thyroid cancer was similar between patients with a solitary nodule (175 of 1181 patients, 14.8%) and patients with multiple nodules (120 of 804, 14.9%) (P = 0.95, chi(2)). A solitary nodule had a higher likelihood of malignancy than a nonsolitary nodule (P < 0.01). In patients with multiple nodules larger than 10 mm, cancer was multifocal in 46%, and 72% of cancers occurred in the largest nodule. Multiple logistic regression analysis of statistically significant features demonstrates that the combination of patient gender (P < 0.02), whether a nodule is solitary vs. one of multiple (P < 0.002), nodule composition (P < 0.01), and presence of calcifications (P < 0.001) can be used to assign risk of cancer to each individual nodule. Risk ranges from a 48% likelihood of malignancy in a solitary solid nodule with punctate calcifications in a man to less than 3% in a noncalcified predominantly cystic nodule in a woman. CONCLUSIONS: In a patient with one or more thyroid nodules larger than 10 mm in diameter, the likelihood of thyroid cancer per patient is independent of the number of nodules, whereas the likelihood per nodule decreases as the number of nodules increases. For exclusion of cancer in a thyroid with multiple nodules larger than 10 mm, up to four nodules should be considered for FNA. Sonographic characteristics can be used to prioritize nodules for FNA based on their individual risk of cancer. 相似文献
142.
Long KZ Santos JI Rosado JL Lopez-Saucedo C Thompson-Bonilla R Abonce M DuPont HL Hertzmark E Estrada-Garcia T 《The Journal of infectious diseases》2006,194(9):1217-1225
BACKGROUND: The overall effect of vitamin A supplementation on diarrheal disease in community trials may result from its effect on specific diarrheal pathogens. METHODS: We conducted a placebo-controlled, double-blind trial of the prophylactic effect of vitamin A on gastrointestinal pathogen infections and clinical symptoms among 188 children in Mexico City, Mexico, from January 1998 to May 1999. Children 6-15 months of age were randomly assigned to receive either a vitamin A supplement (for children <12 months of age, 20,000 international units [IU] of retinol; for children > or =12 months of age, 45,000 IU of retinol) every 2 months or a placebo and were followed for up to 15 months. Stool samples, collected semimonthly, were screened for enteropathogenic Escherichia coli (EPEC), enterotoxigenic E. coli (ETEC), Shiga toxin-producing E. coli (STEC), enteroinvasive E. coli (EIEC), and Giardia lamblia. RESULTS: Vitamin A supplementation reduced the prevalence of EPEC infections (rate ratio [RR], 0.52 [95% confidence interval {CI}, 0.23-0.86]) and led to shorter durations of both EPEC and ETEC infections. Supplementation also reduced the prevalence of EPEC-associated diarrhea (RR, 0.41 [95% CI, 0.16-1.00]), EPEC-associated fever (RR, 0.15 [95% CI, 0.02-0.98]), and G. lamblia-associated fever (RR, 0.27 [95% CI, 0.13-0.80]). Finally, children who received vitamin A supplementation had shorter durations of EPEC-associated diarrhea than did children who did not receive supplementation but had longer durations of G. lamblia-associated diarrhea. CONCLUSIONS: These results suggest that the effect of vitamin A supplementation on clinical outcomes may be pathogen dependent. 相似文献
143.
Ledesma-Montes C Vega-Memije E Garcés-Ortíz M Cardiel-Nieves M Juárez-Luna C 《Medicina oral, patología oral y cirugía bucal》2005,10(5):394-401
Multifocal epithelial hyperplasia (MEH) is also known as focal epithelial hyperplasia, Heck's disease or multifocal papillomavirus-induced epithelial hyperplasia. It is characterised by the presence of multiple lesions in the oral mucosa of children and it has been associated with the presence of the human papillomavirus. The aim of this study was to determine the clinico-pathological features of the cases diagnosed as MEH in the Service of Dermatology of the Hospital Manuel Gea González (SDHMGG). The files of the SDHMGG were reviewed and all cases diagnosed as MEH were retrieved. Nine MEH cases were found. Most of the patients were 20 year-old or younger (67%) and females were more commonly affected (78%). All patients presented multiple lesions and always, close relatives with similar lesions were found. Lesions were located most commonly in the buccal mucosa, lower lip and commissures. MEH is a soft tissue intraoral condition that needs treatment solely of the traumatised lesions or those with cosmetic problems. Remaining lesions will disappear with the age of the patients. It is suggested that this entity should be named multifocal epithelial hyperplasia since this name describes better the clinico-pathological and microscopic features of the disease. 相似文献
144.
145.
Association of the serotonin transporter and receptor gene polymorphisms in neuropsychiatric symptoms in Alzheimer disease 总被引:2,自引:0,他引:2
Assal F Alarcón M Solomon EC Masterman D Geschwind DH Cummings JL 《Archives of neurology》2004,61(8):1249-1253
BACKGROUND: Serotonin has been linked to neuropsychiatric symptoms in Alzheimer disease, mainly agitation/aggression, depression, and psychosis. Neuropsychiatric symptoms have been associated with polymorphisms of the promoter region (5-HTTPR ) and intron 2 of the serotonin transporter gene (5-HTTVNTR) or the 5-HT2A and 5-HT2C receptor genes in some but not all studies. OBJECTIVE: To examine the association of the serotonin promoter, transporter, and receptor genes with neuropsychiatric symptoms in patients with Alzheimer disease. METHODS: The sample included 96 patients with Alzheimer disease from the outpatient clinic of the University of California Los Angeles Alzheimer's Disease Research Center, Los Angeles. The Neuropsychiatric Inventory was used to measure neuropsychiatric symptoms, and blood samples were available for genetic analysis. Based on the literature, we hypothesized that the 5-HT2A and 5-HT2C receptor polymorphisms would be associated with agitation/aggression and psychosis and the 5-HTTPR or 5-HTTVNTR polymorphisms, with agitation/aggression or depression and anxiety. One-way analyses of variance were performed with age, ethnicity, sex, or education as covariates. RESULTS: The 102T genotype of the 5-HT2A receptor was significantly associated with delusions (P =.045) and agitation/aggression (P =.002). We did not replicate previous associations of the 5-HT2C receptor polymorphism with psychosis or of the 5-HTTPR polymorphism with agitation/aggression, psychosis, or depression. We did not find any associations with the 5-HTTVNTR polymorphism and agitation/aggression, depression, or anxiety. CONCLUSIONS: The 5-HT2A receptor polymorphism may contribute to the expression of psychosis and agitation/aggression in patients with Alzheimer disease. Absence of other positive associations may be due to the relatively small sample size and/or potentially small effect size of the polymorphisms and requires further study. 相似文献
146.
147.
Scott C. Williams MD Maricela Contreras Mike McBiles Michael A. Cawthon Rashmikant B. Shah 《Journal of digital imaging》1997,10(2):51-56
Radiographic correlation is essential for many of the examinations performed in nuclear medicine. The purpose of this study was to evaluate the impact of a picture archiving and communications system (PACS) on the function and efficiency of a nuclear medicine department at a tertiary care institution. We evaluated 250 consecutive noncardiac nuclear medicine imaging examinations and asked the interpreting physician the following questions: (1) Was PACS used in the interpretation of the study? (2) Did the use of PACS expedite examination completion or aid in study interpretation? And (3) Did the use of PACS permit a definitive diagnosis to be made? PACS was accessed for correlative radiographic images in 155 of the 250 (62%) nuclear medicine examinations. Images available on PACS for review aided in study interpretation in 74% (115 of 155) of cases The use of PACS was thought to expedite examination completion in 55% (86 of 155) of cases. The system was accessed but not operational in only 1% of cases (2 of 155). PACS provides reliable, rapid access to multimodality correlative radiographic images that aid in the interpretation of nuclear medicine examinations. Such systems also increase the efficiency of a nuclear medicine service by allowing timely and conclusive interpretations to be made.Key words: picture archive and communication systems, computers, nuclear medicine 相似文献
148.
Magnitude‐dependent and inversely‐related osteogenic/chondrogenic differentiation of human mesenchymal stem cells under dynamic compressive strain 下载免费PDF全文
Christopher B. Horner Koji Hirota Junze Liu Maricela Maldonado B. Hyle Park Jin Nam 《Journal of tissue engineering and regenerative medicine》2018,12(2):e637-e647
Biomechanical forces have been shown to significantly affect tissue development, morphogenesis, pathogenesis and healing, especially in orthopaedic tissues. Such biological processes are critically related to the differentiation of human mesenchymal stem cells (hMSCs). However, the mechanistic details regarding how mechanical forces direct MSC differentiation and subsequent tissue formation are still elusive. Electrospun three‐dimensional scaffolds were used to culture and subject hMSCs to various magnitudes of dynamic compressive strains at 5, 10, 15 or 20% (ε = 0.05, 0.10, 0.15, 0.20) at a frequency of 1 Hz for 2 h daily for up to 28 days in osteogenic media. Gene expression of chondrogenic markers (ACAN, COL2A1, SOX9) and glycosaminoglycan (GAG) synthesis were upregulated in response to the increased magnitudes of compressive strain, whereas osteogenic markers (COL1A1, SPARC, RUNX2) and calcium deposition had noticeable decreases by compressive loading in a magnitude‐dependent manner. Dynamic mechanical analysis showed enhanced viscoelastic modulus with respect to the increased dynamic strain peaking at 15%, which coincides with the maximal GAG synthesis. Furthermore, polarization‐sensitive optical coherence tomography revealed that mechanical loading enhanced the alignment of extracellular matrix to the greatest level by 15% strain as well. Overall, we show that the degree of differentiation of hMSCs towards osteogenic or chondrogenic lineage is inversely related, and it depends on the magnitude of dynamic compressive strain. These results demonstrate that multiphenotypic differentiation of hMSCs can be controlled by varying the strain regimens, providing a novel strategy to modulate differentiation specification and tissue morphogenesis. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献
149.
Muñoz P Rojas L Cervera C Garrido G Fariñas MC Valerio M Giannella M Bouza E;COMIT Study Group 《Clinical transplantation》2012,26(1):87-96
The rate of compliance with antifungal drug use guidelines by transplant physicians is mostly unknown. We performed a nationwide electronic survey to assess antifungal use by different types of transplant physicians. Sixty-one percent (53/87) of the transplant programs responded (accounting for 85% of heart transplant procedures, 65% of kidney transplantations, and 71.5% of liver transplantations). Antifungal prophylaxis was used in 41.5% programs (liver 93.3%, heart 30.8%, and kidney 16%). Prophylaxis was universal in 32% of the programs and targeted only to selected patients in 68%, mainly indicated after re-transplantation (73.3%), re-intervention (66.7%) and hemodialysis (60%). Main drugs for universal prophylaxis were fluconazole and itraconazole (42.9% each), while fluconazole (60%), L-amphotericin B (AMB), and caspofungin (13.4% each) were preferred for targeted prophylaxis. Overall, 84.9% of the programs used galactomannan for the diagnosis of invasive aspergillosis (only 34% in BAL) and 66.6% used voriconazole as first-line monotherapy. Combination first-line therapy for invasive aspergillosis was used by 31.3%, mainly with voriconazole with caspofungin (40%) or anidulafungin (26.7%) or L-AMB-caspofungin (26.7%). Adherence of transplant physicians to current recommendations on antifungal treatment and prophylaxis is poor. An international consensus that responds to differences in patients and centers and emphasizes patient safety is clearly needed. 相似文献
150.