全文获取类型
收费全文 | 28272篇 |
免费 | 2314篇 |
国内免费 | 1108篇 |
专业分类
耳鼻咽喉 | 279篇 |
儿科学 | 328篇 |
妇产科学 | 580篇 |
基础医学 | 4637篇 |
口腔科学 | 1301篇 |
临床医学 | 2270篇 |
内科学 | 4208篇 |
皮肤病学 | 416篇 |
神经病学 | 1691篇 |
特种医学 | 1700篇 |
外国民族医学 | 4篇 |
外科学 | 2986篇 |
综合类 | 2750篇 |
现状与发展 | 10篇 |
预防医学 | 933篇 |
眼科学 | 224篇 |
药学 | 1405篇 |
5篇 | |
中国医学 | 120篇 |
肿瘤学 | 5847篇 |
出版年
2024年 | 16篇 |
2023年 | 1649篇 |
2022年 | 2313篇 |
2021年 | 2020篇 |
2020年 | 2430篇 |
2019年 | 1513篇 |
2018年 | 1166篇 |
2017年 | 1384篇 |
2016年 | 1461篇 |
2015年 | 1524篇 |
2014年 | 3263篇 |
2013年 | 2102篇 |
2012年 | 1523篇 |
2011年 | 1112篇 |
2010年 | 1823篇 |
2009年 | 1606篇 |
2008年 | 574篇 |
2007年 | 906篇 |
2006年 | 650篇 |
2005年 | 522篇 |
2004年 | 304篇 |
2003年 | 251篇 |
2002年 | 207篇 |
2001年 | 254篇 |
2000年 | 150篇 |
1999年 | 222篇 |
1998年 | 268篇 |
1997年 | 195篇 |
1996年 | 261篇 |
1995年 | 7篇 |
1994年 | 1篇 |
1993年 | 1篇 |
1990年 | 1篇 |
1989年 | 4篇 |
1985年 | 1篇 |
1984年 | 4篇 |
1983年 | 3篇 |
1980年 | 1篇 |
1971年 | 1篇 |
1941年 | 1篇 |
排序方式: 共有10000条查询结果,搜索用时 328 毫秒
1.
《Journal of diabetes and its complications》2022,36(8):108260
AimTo verify whether arterial stiffness and endothelial dysfunction influence lower limb muscle strength and gait speed in older adults with type 2 diabetes mellitus (T2DM).MethodsCross-sectional study including seventy-eight older adults with T2DM (aged 67 ± 6 years and 42 % male). Arterial stiffness was assessed using pulse wave velocity (PWV), while endothelial function was measured by flow-mediated dilation (FMD). Lower limb muscle strength and gait speed were assessed using the 30-second chair stand test (30s-CST) and 10-Meter Walk Test, respectively.ResultsBoth PWV (m/s) and FMD (%) were univariately associated with number of repetitions in 30s-CST and gait speed (P < 0.05). After control for age, sex and body mass index, PWV remained associated with repetitions in 30s-CST (95 % CI: ?0.494 to ?0.054; P = 0.015) and gait speed (95 % CI: ?0.039 to ?0.002; P = 0.031). After adjustments for control variables, T2DM duration and glycemic control, FMD was associated with repetitions in 30s-CST (95 % CI: 0.008 to 0.324; P = 0.039) and gait speed (95 % CI: 0.011 to 0.038; P = 0.001).ConclusionIn older adults with T2DM, both arterial stiffness and endothelial dysfunction are associated with decreased leg muscle strength and slower gait speed. 相似文献
2.
3.
A 25-year-old, emaciated man without medical treatment was found to have died suddenly at home by his mother. At autopsy, there were no injuries to his body, but significant circulatory insufficiency was observed. Electron microscopy revealed abnormal mitochondria in cells of the cardiac conduction system. The conduction system was filled with mitochondrial size abnormalities and mitochondrial cristae abnormalities. No notable abnormal findings were observed in other organs. Genetic examination of the blood revealed the mitochondrial pathogenetic variant m.3243A>G. Epileptic seizures, diabetic ketoacidosis, and hyperosmolar hyperglycemic state were unlikely to be the cause of sudden death. The cause of death was diagnosed as arrhythmia possibly induced by the failure of the cardiac conduction system due to mitochondrial disease. This is a rare case of sudden death caused by an accumulation of abnormal mitochondria in the cardiac conduction system. 相似文献
4.
In forensic medicine, although various alcohols have been reported as indicators of decomposition in collected blood, no studies have examined short-chain fatty acids as indicators. In this study, the blood n-butyric acid concentration was quantified, and the association between n-butyric acid and decomposition was investigated to determine whether the detection of n-butyric acid could be a new indicator of decomposition. Among the forensic autopsies performed from 2016 to 2018 in our laboratory, the cases were divided into decomposed (n = 20) and non-decomposed (n = 20) groups based on macroscopic findings. Blood samples collected at the time of autopsy were derivatized with 3-nitrophenylhydrazine hydrochloride after solid-phase extraction. The n-butyric acid concentration was measured using liquid chromatography–tandem mass spectrometry. In addition, ethanol and n-propanol were measured using a gas chromatography-flame ionization detector. There was a significant difference (p < 0.01) in the concentrations of n-butyric acid between the decomposed and non-decomposed groups (0.343 ± 0.259 [0.030–0.973] and 0.003 ± 0.002 [0.001–0.007] mg/mL, respectively). In the decomposed group, n-butyric acid was detected at high concentrations, even in cases where n-propanol was low. These results suggest that n-butyric acid is more likely to be an indicator of blood decomposition than n-propanol. 相似文献
5.
6.
7.
BackgroundFocal liver lesions with spindle cell morphology are rare in the daily practice of pathology. The differential diagnosis is broad, including both tumors and tumor-like lesions. Initial radiologic assessment is sometimes inaccurate. Histopathology is needed to arrive at the correct diagnosis. This study analyzed discrepancies between histopathology and radiologic findings of focal liver lesions with spindle cell morphology.MethodsA six-year retrospective analysis was conducted at a tertiary hospital in Thailand. All focal liver lesions with spindle cell morphology were retrieved. Clinicopathologic features of these cases were analyzed. The pathological diagnosis was rendered primarily based on routine histopathology, using other ancillary studies as an adjunct.Results287 biopsies and 151 resection specimens with focal liver lesions were identified. In 12 (2.7%) cases, tumors or tumor-like lesions with spindle cell morphology were retrieved. A total of five cases had discrepancies between histopathology and radiologic findings. These lesions encompassed primary liver tumors (EBV-associated smooth muscle tumor and leiomyosarcoma); metastatic tumors (gastrointestinal stromal tumor, small cell neuroendocrine carcinoma); and a tumor-like lesion (endometriosis). Several morphologic findings (i.e., cytologic grades, dense and loose areas, intratumoral lymphocytes, distinct perinuclear vacuoles, and hemosiderin) are important clues to diagnose these spindle cell lesions.ConclusionsPathologists play a critical role in diagnosing focal liver lesions with spindle cell morphology, particularly those with limited clinical data at the initial presentation. A thorough evaluation of histomorphology on routine hematoxylin and eosin-stained slides is essential for correct diagnosis. 相似文献
8.
AimGenomic-based ancillary assays including immunohistochemistry (IHC) for BRCA-1 associated protein-1 (BAP1) and methylthioadenosine phosphorylase (MTAP), and fluorescence in situ hybridization (FISH) for CDKN2A are effective for differentiating pleural mesothelioma (PM) from reactive mesothelial proliferations. We previously reported a combination of MTAP and BAP1 IHC effectively distinguishes sarcomatoid PM from fibrous pleuritis (FP). Nevertheless, cases of sarcomatoid PM with desmoplastic features (desmoPM) are encountered where the IHC assessment is unclear.Methods and resultsWe evaluated assessment of MTAP IHC, BAP1 IHC, and CDKN2A FISH in 20 desmoPM compared to 24 FP. MTAP and BAP1 IHC could not be assessed in 11 (55 %) and 10 (50 %) cases, respectively, due to loss or faint immunoreactivity of internal positive control cells, while CDKN2A FISH could be evaluated in all cases. The sensitivities for MTAP loss, BAP1 loss, and CDKN2A homozygous deletion in desmoPM were 40 %, 10 %, and 100 %. A combination of MTAP loss and BAP1 loss yielded 45 % of sensitivity.ConclusionsMTAP IHC is a useful surrogate diagnostic marker in differentiating ordinary sarcomatoid PM from FP, but its effectiveness is limited in desmoPM. CDKN2A FISH is the most effective diagnostic assays with 100 % sensitivity and specificity in discriminating desmoPM from FP in the facilities where the FISH assay is available. 相似文献
9.
《Survey of ophthalmology》2023,68(4):815-820
An 8-year-old boy presented with acute visual loss in the right eye and nausea, vomiting, and diplopia. Imaging revealed a right orbital apex mass. Biopsy showed Langerhans cell histiocytosis (LCH), and the patient was diagnosed with isolated orbital LCH causing an orbital apex syndrome. A 12-month cytarabine chemotherapy course was begun, during which the patient developed bilateral optic disc edema. He was diagnosed with cytarabine-induced intracranial hypertension, which was successfully treated with acetazolamide. The cytarabine course was completed with complete resolution of the LCH lesion. The ophthalmologic relevance of this rare disorder is discussed. 相似文献
10.
《Clinics and research in hepatology and gastroenterology》2022,46(9):102020
Background and aimsWe intended to investigate the predictors for bowel resection in infants with necrotizing enterocolitis (NEC). We further developed a scoring system for better predicting bowel resection.MethodsA total of 207 infants who underwent surgical management at Children's Hospital, Chongqing Medical University between April 2008 and December 2020 were identified for the following investigation. Bowel resection was reviewed among the infants who underwent the procedure. Potential parameters related to bowel resection were explored using a multiple logistic regression method, and then a scoring system was developed.ResultsAmong the 207 patients who underwent operative intervention that were reviewed, 109 infants underwent bowel resection. Multivariate logistic regression analysis showed that birth weight, hypotension, neutropenia, pneumoperitoneum, acidosis, and intestinal wall thickness were predictors related to the occurrence of bowel resection. A 6-point scoring system was further developed based on the obtained total coefficient, and the infants could be divided into low-, moderate- and high-risk groups according to cut values of 7 and 13.ConclusionThe results of this study demonstrated that severe NEC features and low birth weight were associated with bowel resection. The risk scoring system could accurately separate infants that were suspected to have bowel loss during surgery. 相似文献