全文获取类型
收费全文 | 6075篇 |
免费 | 2443篇 |
国内免费 | 32篇 |
专业分类
耳鼻咽喉 | 185篇 |
儿科学 | 179篇 |
妇产科学 | 195篇 |
基础医学 | 74篇 |
口腔科学 | 42篇 |
临床医学 | 1065篇 |
内科学 | 1837篇 |
皮肤病学 | 418篇 |
神经病学 | 590篇 |
特种医学 | 185篇 |
外科学 | 2103篇 |
综合类 | 13篇 |
预防医学 | 520篇 |
眼科学 | 509篇 |
药学 | 47篇 |
肿瘤学 | 588篇 |
出版年
2024年 | 87篇 |
2023年 | 675篇 |
2022年 | 72篇 |
2021年 | 249篇 |
2020年 | 374篇 |
2019年 | 138篇 |
2018年 | 635篇 |
2017年 | 705篇 |
2016年 | 607篇 |
2015年 | 554篇 |
2014年 | 745篇 |
2013年 | 658篇 |
2012年 | 273篇 |
2011年 | 246篇 |
2010年 | 458篇 |
2009年 | 612篇 |
2008年 | 226篇 |
2007年 | 93篇 |
2006年 | 148篇 |
2005年 | 81篇 |
2004年 | 50篇 |
2003年 | 38篇 |
2002年 | 42篇 |
2001年 | 98篇 |
2000年 | 42篇 |
1999年 | 72篇 |
1998年 | 81篇 |
1997年 | 88篇 |
1996年 | 57篇 |
1995年 | 59篇 |
1994年 | 38篇 |
1993年 | 32篇 |
1992年 | 38篇 |
1991年 | 33篇 |
1990年 | 19篇 |
1989年 | 17篇 |
1988年 | 21篇 |
1987年 | 12篇 |
1986年 | 8篇 |
1985年 | 4篇 |
1984年 | 5篇 |
1983年 | 7篇 |
1982年 | 13篇 |
1981年 | 9篇 |
1980年 | 7篇 |
1979年 | 4篇 |
1978年 | 3篇 |
1977年 | 3篇 |
1972年 | 2篇 |
1971年 | 3篇 |
排序方式: 共有8550条查询结果,搜索用时 15 毫秒
991.
Post‐operative survival following metastasectomy for patients receiving BRAF inhibitor therapy is associated with duration of pre‐operative treatment and elective indication 下载免费PDF全文
992.
Murali R Goumas C Kricker A From L Busam KJ Begg CB Dwyer T Gruber SB Kanetsky PA Orlow I Rosso S Thomas NE Berwick M Scolyer RA Armstrong BK;GEM Study Group 《Annals of surgical oncology》2012,19(3):1024-1033
Background
0.6?C12.7% of patients with primary cutaneous melanoma will develop additional melanomas. Pathologic features of tumors in patients with multiple primary cutaneous melanomas have not been well described. In this large, international, multicenter, case?Ccontrol study, we compared the clinicopathologic features of a subsequent melanoma with the preceding (usually the first) melanoma in patients with multiple primary cutaneous melanomas, and with those of melanomas in patients with single primary cutaneous melanomas.Methods
Multiple primary melanoma (cases) and single primary invasive melanoma (controls) patients from the Genes, Environment and Melanoma (GEM) study were included if their tumors were available for pathologic review and confirmed as melanoma. Clinicopathologic characteristics of invasive subsequent and first melanomas in cases and invasive single melanomas in controls were compared.Results
A total of 473 pairs comprising a subsequent and a first melanoma and 1,989 single melanomas were reviewed. Forward stepwise regression modeling in 395 pairs with complete data showed that, compared with first melanomas, subsequent melanomas were more commonly contiguous with a dysplastic nevus, more prevalent on the head/neck and legs than other sites, and thinner. Compared with single primary melanomas, subsequent melanomas were more likely to be associated with a contiguous dysplastic nevus, more prevalent on the head/neck and legs, and thinner. The same differences were observed when subsequent melanomas were compared with single melanomas. First melanomas were more likely than single melanomas to have associated solar elastosis and no observed mitoses.Conclusions
Thinner subsequent than first melanomas suggest earlier diagnosis, perhaps due to closer clinical scrutiny. The association of subsequent melanomas with dysplastic nevi is consistent with the latter being risk factors or risk markers for melanoma. 相似文献993.
Background
The prognostic significance of size of central lymph node metastasis (CLNM) in papillary thyroid carcinoma (PTC) remains unknown. Because postsurgical detectable stimulated thyroglobulin (DsTg) after radioiodine ablation may imply persistent or recurrent disease, we evaluated the association between size of CLNM and rate of DsTg in patients with PTC who underwent unilateral prophylactic central neck dissection.Methods
To be eligible for analysis, the prophylactic central neck dissection specimen with <3 central lymph nodes (CLNs) or size of CLNM ??1?cm as measured under the microscope was excluded. Of 132 specimens, 89 (67.4?%) were eligible. Forty patients (44.9?%) had no metastasis or pN0, 20 (22.5?%) had micrometastasis (<2?mm) or pN1mic and 29 (32.6?%) had macrometastasis (??2?mm) or pN1mac. Postablation sTg level was measured 9?months after surgery. A multivariable analysis was conducted to identify independent factors for postablation DsTg.Results
Larger-sized CLNM correlated significantly with younger age (p?=?0.028), greater number of CLN retrieved (p?=?0.016), greater number of metastatic CLN excised (p?0.001), higher metastatic CLN ratio (p?=?0.006) and postablation sTg level (p?=?0.012). In the multivariable analysis, after adjusting for tumor size and metastatic CLN ratio, size of CLNM was an independent predictor of postablation DsTg (odds ratio 1.56, 95?% confidence interval 1.09?C2.24, p?=?0.015). Relative to pN0, the odds ratios for postablation DsTg in pN1mic and pN1mac were 2.53 (95?% confidence interval 0.35?C19.00, p?=?0.351) and 5.81 (95?% confidence interval 1.22?C27.70, p?=?0.027), respectively.Conclusions
Size of CLNM was an independent factor for DsTg 9?months after surgery. Patients with pN1mac were almost 6 times more likely to have postablation DsTg than those with pN0 or pN1mic. 相似文献994.
995.
OPINION STATEMENT: Systemic immunopathological diseases with prominent neurological features include systemic lupus erythematosus (SLE), rheumatoid arthritis (RA), Sj?gren's Syndrome (SS), and the systemic vasculitides. These systemic conditions can affect the nervous system in diverse ways. In many cases, the neurological disease heralds the onset of the systemic condition. Recognizing the pattern of neurological and systemic features of these conditions is critical in order to uncover the systemic condition in a timely manner. Although treatment of these conditions is usually directed at the underlying systemic disease, discovery of certain types of neurological involvement such as rapidly progressive mononeuritis multiplex may often necessitate more robust immunosuppressive therapy. The larger treatment trials addressing optimal therapy in these conditions are coordinated by rheumatologists and rarely address the neurological complications in isolation. As such, the evidence supporting neurology-specific therapy regimens is generally an extrapolation of findings that apply to the systemic condition as a whole and cannot be considered as Class I. Less severe neurological manifestations are often treated with glucocorticoids and immunosuppressive treatments such as azathioprine as a steroid-sparing strategy. More severe neurological involvement requires early and aggressive therapy with powerful immunosuppressive agents, often in combination with glucocorticoids and plasma exchange. Cyclophosphamide is the most established immunosuppressive therapy in this context but is limited by its toxicity. Rituximab is emerging as a highly promising alternative although its high cost is a major limitation. 相似文献
996.
Background
Periprosthetic joint infection is a particularly difficult orthopedic problem, complicating a growing number of revision procedures. Joint debridement and systemic antibiotics are the mainstay of treatment, yet difficulty remains in maintaining a minimum inhibitory concentration of antibiotic at the localized site of infection.Study Aims
This study analyzes the elution characteristics of a 40%bwt calcium phosphate–60%bwt calcium sulfate composite, at varying concentrations of vancomycin.Methods
Four groups of varying concentrations of vancomycin (2.63%bwt, 5.13%, 9.76%, and 17.78%) were mixed with one pack of the composite cement. At designated time intervals up to 28 days, the antibiotic concentration was detected using fluorescence polarization immunoassay and the elution trends compared.Results
The elution rate of each of the four groups decreased over time. At almost all of the intervals, the elution rates of the higher concentration groups were significantly higher than the lower concentration groups (P < 0.05).Conclusions
Calcium sulfate reabsorbs over a prolonged period, producing porosity which allows for new bone ingrowth through occupation of osteoprogenitor cells and osteoblasts; while calcium phosphate acts as a long-term osteoconductive matrix.Clinical Relevance
The results of this study suggest that vancomycin can be mixed affectively with a calcium sulfate/phosphate composite, both maintaining stability and eluting gradually over a clinically relevant period of time. 相似文献997.
998.
999.
1000.