全文获取类型
收费全文 | 10598篇 |
免费 | 657篇 |
国内免费 | 42篇 |
专业分类
耳鼻咽喉 | 97篇 |
儿科学 | 253篇 |
妇产科学 | 274篇 |
基础医学 | 1526篇 |
口腔科学 | 213篇 |
临床医学 | 1046篇 |
内科学 | 2529篇 |
皮肤病学 | 126篇 |
神经病学 | 891篇 |
特种医学 | 339篇 |
外科学 | 1347篇 |
综合类 | 114篇 |
一般理论 | 13篇 |
预防医学 | 824篇 |
眼科学 | 200篇 |
药学 | 777篇 |
中国医学 | 7篇 |
肿瘤学 | 721篇 |
出版年
2023年 | 63篇 |
2022年 | 86篇 |
2021年 | 204篇 |
2020年 | 157篇 |
2019年 | 190篇 |
2018年 | 235篇 |
2017年 | 177篇 |
2016年 | 158篇 |
2015年 | 254篇 |
2014年 | 313篇 |
2013年 | 488篇 |
2012年 | 762篇 |
2011年 | 773篇 |
2010年 | 406篇 |
2009年 | 366篇 |
2008年 | 680篇 |
2007年 | 727篇 |
2006年 | 697篇 |
2005年 | 663篇 |
2004年 | 637篇 |
2003年 | 582篇 |
2002年 | 621篇 |
2001年 | 134篇 |
2000年 | 141篇 |
1999年 | 149篇 |
1998年 | 125篇 |
1997年 | 113篇 |
1996年 | 96篇 |
1995年 | 97篇 |
1994年 | 76篇 |
1993年 | 84篇 |
1992年 | 92篇 |
1991年 | 96篇 |
1990年 | 68篇 |
1989年 | 59篇 |
1988年 | 60篇 |
1987年 | 50篇 |
1986年 | 60篇 |
1985年 | 48篇 |
1984年 | 48篇 |
1983年 | 36篇 |
1982年 | 57篇 |
1981年 | 33篇 |
1980年 | 28篇 |
1979年 | 29篇 |
1978年 | 29篇 |
1977年 | 35篇 |
1976年 | 20篇 |
1975年 | 32篇 |
1973年 | 24篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
81.
OBJECTIVE: Hpr6 (heme-1 domain protein/human progesterone receptor) is one of a family of proteins that are implicated in progesterone metabolism, resistance to genotoxic agents and steroid biosynthesis. Because these processes are frequently misregulated in tumors, we have examined the expression of Hpr6 in a group of clinical tumor samples and cancer cell lines. METHODS: Hpr6 expression was analyzed by Western blot in extracts from breast, cervix, colon and thyroid cell lines and in nonmalignant and adjacent tumor tissue from breast, colon and thyroid. Hpr6 localization was determined by immunofluorescence. RESULTS: Hpr6 expression is significantly elevated in breast tumors in comparison with matched nonmalignant tissue and demonstrated limited overexpression in colon and thyroid tumors. Hpr6 is strongly expressed in a panel of tumor cell lines originating from breast, thyroid and colon. Hpr6 localizes to the perinuclear region of the cell, consistent with a role in cell detoxification, signaling and/or sterol synthesis. CONCLUSIONS: Hpr6 homologues regulate cytochrome P450 proteins implicated in hormone, steroid and xenobiotic chemical metabolism. These are the first studies linking Hpr6 expression to cancer progression and cellular survival. Our results suggest that Hpr6 is an important marker for cancer progression and a potential anticancer therapeutic target. 相似文献
82.
83.
84.
Eoin Moynihan Katrina Mackey Mark A. T. Blaskovich F. Jerry Reen Gerard McGlacken 《ACS medicinal chemistry letters》2022,13(8):1358
Antibiotic resistance has grown significantly in the last three decades, while research and development of new antibiotic classes has languished. Therefore, new chemical frameworks for the control of microbial behavior are urgently required. This study presents a novel suite of compounds, based on a tricyclic 4-hydroxy-2H-pyrano[3,2-c]quinoline-2,5(6H)-dione core, with significant antibiotic activity against the ESKAPE pathogens Staphylococcus aureus and Enterococcus faecalis and the “accidental pathogen” Staphylococcus epidermidis. A potent analogue with an N-heptyl-9-t-Bu substitution pattern emerged as a hit with MIC levels ≤2 μg/mL across four strains of MRSA. In addition, the same compound proved highly potent against Enterococcus spp. (0.25 μg/mL). 相似文献
85.
86.
Kevin Martell Hans Chung Gerard Morton Danny Vesprini Chia-Lin Tseng Ewa Szumacher Patrick Cheung Will Chu Stanley Liu Andrew Loblaw 《Canadian Urological Association journal》2022,16(8):E437
IntroductionWe aimed to determine the minimum cross-sectional ellipsoid area on magnetic resonance (MR) of intraprostatic nodules that best predicts for subsequent targeted biopsies revealing ≥ grade group (GG) 2 disease.MethodsForty-six patients previously diagnosed with GG 1 prostate adenocarcinoma who received cognitively fused, MR-guided, transperineal targeted biopsies in addition to six random biopsies were included in this analysis. A Youden cutpoint analysis was used to determine the ellipsoid area in the axial plane best predicting for ≥GG 2 disease within the targeted biopsy cores and logistic regression used to assess the result.ResultsMedian time from MR imaging to targeted biopsy was 2.4 (1.4–5.5) months. Forty of 46 (87%) patients had one nodule and 6/46 (13%) had two separate nodules on MR that received targeted biopsy. Of the 52 nodules, five (10%), 33 (63%), and 14 (27%) were Prostate Imaging-Reporting and Data System (PI-RADS) 3, 4, and 5, respectively. Thirteen (25%), six (12%), and 33 (64%) were in the anterior, medial, and posterior regions of the prostate, respectively. Median area was 0.72 (0.49–1.29) cm2 (average diameter 9.5 mm). Fifteen of 46 (33%) patients had ≥1 random biopsy and 20/52 (38%) nodules had ≥1 targeted biopsy revealing ≥GG 2 disease. The optimal area cutpoint was ≥0.7 cm2, with an area under the curve of 0.671 (0.510–0.832). On logistic regression, area ≥0.7 cm2 was solely predictive of targeted biopsy revealing ≥GG 2 disease (odds ratio 6.5, 1.3–32.4, p=0.022).ConclusionsNodule area ≥0.7 cm2 may predict for transperineal-based targeted biopsies being positive for ≥GG 2 disease when 1–2 cores are taken. 相似文献
87.
88.
89.
Acute otomastoiditis and its complications: role of CT 总被引:2,自引:0,他引:2
Acute bacterial (suppurative) otomastoiditis responds to antibiotic treatment; radiologic study is required only when there is clinical suggestion of coalescent mastoiditis, intracranial complications, or an underlying chronic disease. Computed tomography (CT) is the method of choice for evaluating otogenic intra- or extra-cranial complications. CT scans can show stages of disease progression when infection has spread by way of soft tissue, blood, and bone pathways into the dural venous sinuses, meninges, labyrinth, facial nerves, epidural and other intracranial spaces. When there is clinical suggestion of acute coalescent mastoiditis, a CT scan of the temporal bone can confirm the presence of rarefying osteitis, coalescence of the air cells, and subperiosteal abscess. 相似文献
90.
Radiation treatment of bladder squamous cell carcinoma in a patient with spina bifida: A case report
Neil D��Souza Gerard Morton Hans T. Chung 《Canadian Urological Association journal》2012,6(3):E125-E128
Bladder cancer is the sixth most common cancer in Canada. While most patients present with transitional cell carcinoma, few present with squamous cell carcinoma (SCC). Risk factors for SCC include a history of chronic urinary tract infection, urothelial inflammation and indwelling catheters. We present the management of a patient with locally advanced SCC of the bladder. 相似文献