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   1600673篇
  免费   120236篇
  国内免费   3820篇
耳鼻咽喉   21252篇
儿科学   53630篇
妇产科学   46860篇
基础医学   225324篇
口腔科学   44756篇
临床医学   140834篇
内科学   318596篇
皮肤病学   38132篇
神经病学   128937篇
特种医学   63887篇
外国民族医学   543篇
外科学   238924篇
综合类   33852篇
现状与发展   3篇
一般理论   494篇
预防医学   126636篇
眼科学   36015篇
药学   111998篇
  3篇
中国医学   3632篇
肿瘤学   90421篇
  2021年   12050篇
  2019年   12610篇
  2018年   20796篇
  2017年   16837篇
  2016年   17740篇
  2015年   20842篇
  2014年   27189篇
  2013年   37554篇
  2012年   55751篇
  2011年   54015篇
  2010年   31146篇
  2009年   31189篇
  2008年   47492篇
  2007年   50533篇
  2006年   51168篇
  2005年   56967篇
  2004年   56234篇
  2003年   49927篇
  2002年   43949篇
  2001年   76581篇
  2000年   76209篇
  1999年   66206篇
  1998年   17526篇
  1997年   15731篇
  1996年   15927篇
  1995年   15140篇
  1994年   13712篇
  1993年   12841篇
  1992年   51492篇
  1991年   49436篇
  1990年   47736篇
  1989年   45491篇
  1988年   41743篇
  1987年   40809篇
  1986年   38079篇
  1985年   35927篇
  1984年   27065篇
  1983年   22630篇
  1982年   13098篇
  1979年   24201篇
  1978年   16779篇
  1977年   13721篇
  1976年   12806篇
  1975年   13937篇
  1974年   16914篇
  1973年   16098篇
  1972年   15237篇
  1971年   14040篇
  1970年   13308篇
  1969年   12400篇
排序方式: 共有10000条查询结果,搜索用时 46 毫秒
121.
122.
PurposeOur purpose was to determine the effect of chemoradiotherapy (CRT) on patient-reported quality of life (QOL) for patients with intact pancreas cancer.Methods and MaterialsWe reviewed a prospective QOL registry for patients with intact, clinically localized pancreatic ductal adenocarcinoma treated with CRT between June 2015 and November 2018. QOL was assessed pre-CRT (immediately before CRT, after neoadjuvant chemotherapy) and at the completion of CRT with the Functional Assessment of Cancer Therapy-Hepatobiliary (FACT-Hep) and its component parts: FACT-General (FACT-G) and hepatobiliary cancer subscore (HCS). A minimally important difference from pre-CRT was defined as ≥ 6, 5, and 8 points for FACT-G, HCS, and FACT-Hep, respectively.ResultsOf 157 patients who underwent CRT, 100 completed both pre- and post-CRT surveys and were included in the primary analysis. Median age at diagnosis was 65 years (range, 23-90). National Comprehensive Cancer Network resectability status was resectable (3%), borderline resectable (40%), or locally advanced (57%). Folinic acid, 5-fluorouracil, irinotecan, and oxaliplatin (FOLFIRINOX) (75%) or gemcitabine and nab-paclitaxel (42%) were given for a median of 6 cycles (range, 0-42) before CRT. Radiation therapy techniques included 3-dimensional conformal (22%), intensity modulated photon (55%), and intensity modulated proton (23%) radiation therapy to a median dose of 50 Gy (range, 36-62.5). Concurrent chemotherapy was most commonly capecitabine (82%). Sixty-three patients (63%) had surgery after CRT. The mean decline in FACT-G, HCS subscale, and FACT-Hep from pre- to post-CRT was 3.5 (standard deviation [SD], 13.7), 1.7 (SD 7.8), and 5.2 (SD 19.4), respectively. Each of these changes were statistically significant, but did not meet the minimally important difference threshold. Pancreatic head tumor location was associated with decline in FACT-Hep. Nausea was the toxicity with the greatest increase from pre- to post-CRT by both physician-assessment and patient-reported QOL.ConclusionsFor patients with intact pancreatic adenocarcinoma, modern CRT is well tolerated with minimal decline in QOL during treatment.  相似文献   
123.
124.
Psoriasis is a chronic, inflammatory, immune‐mediated disease. Approximately 30% of patients have disease onset before age 18 years. Psoriasis in children and adolescents may be difficult to control, with subsequent poor quality of life and psychosocial consequences. We describe the case of a 12‐year‐old boy with severe, refractory, chronic plaque psoriasis for 6 years. Various therapeutic regimens including different topical corticosteroids, topical vitamin D analogs, phototherapy, photochemotherapy, systemic therapy with methotrexate, cyclosporin, and combination therapies showed only partial or transient responses with frequent relapses. Because anti‐interleukin‐12/23 agents have been successfully used in adults with psoriasis, ustekinumab was initiated and our patient showed a rapid, excellent, sustained response. No recurrence or flares have been observed after 33 months of follow‐up. This case illustrates that ustekinumab may be an effective and safe therapeutic option in adolescents with psoriasis.  相似文献   
125.
126.
Attachment is a behavioral and physiological system, which enables individual’s dynamic adaptation to its environment. Attachment develops in close interaction between an infant and his/her mother, plays an important role in the development of the infant’s brain, and influences the quality of interpersonal relationships throughout life.Security of attachment is believed to influence individual response to stress, exposing insecurely organized individuals to deregulated autonomic nervous system and exaggerated hypothalamic-pituitary-adrenal activity, which, in turn, produces increased and prolonged exposure to stress-hormones. Such stress responses may have considerable implications for the development of diverse health-risk conditions, such as insulin resistance and hyperlipidemia, shown by numerous studies.Although the mechanisms are not yet fully understood, there is compelling evidence highlighting the role of psychological stress in the development of type 1 diabetes (T1D). One of the possible contributing factors for the development of T1D may be the influence of attachment security on individual stress reactivity. Thus, the suggestion is that insecurely attached individuals are more prone to experience increased and prolonged influence of stress hormones and other mechanisms causing pancreatic beta-cell destruction.The present paper opens with a short overview of the field of attachment in children, the principal attachment classifications and their historic development, describes the influence of attachment security on individual stress-reactivity and the role of the latter in the development of T1D. Following is a review of recent literature on the attachment in patients with T1D with a conclusion of a proposed role of attachment organization in the etiology of T1D.  相似文献   
127.
Background. Haemophagocytic lymphohistiocytosis (HLH) is a rare clinical syndrome characterized by fever, hepatosplenomegaly, cytopenia, and progressive multiple-organ failure. HLH in adults is often secondary to autoimmune diseases, cancer, or infections in contrast to familial HLH. Treatment of secondary HLH is directed against the triggering disease in addition to immunosuppressive therapy, the latter commonly according to the HLH-2004 protocol.Methods. We conducted a retrospective study to identify triggering diseases, disease-specific and immunosuppressive therapy administered, and prognosis in adult patients with secondary HLH. Patient data were collected from October 2010 to January 2015.Results. Ten adult patients with secondary HLH were identified. Seven were men, and the median age at diagnosis was 62 years. Five cases were triggered by malignant disease and five by infection. The median patient fulfilled five of the eight HLH-2004 diagnostic criteria. All patients fulfilled the criteria fever, cytopenia, and ferritin >500 µg/L. Median time from hospital admission to HLH diagnosis was 20 days. Four patients received immunosuppressive therapy according to the HLH-2004 protocol. The prognosis was dismal, especially for the patients with malignancy-associated HLH, of whom all died.Conclusion. HLH should be suspected in patients who present with fever, cytopenia, and ferritin >500 µg/L. Secondary HLH has a dismal prognosis. None of the patients with HLH triggered by malignancy survived. Achieving remission of the triggering disease seems to be important for a favourable outcome as, in all surviving patients, the haemophagocytic syndrome resolved after remission of the underlying infection.  相似文献   
128.
129.
130.
Moderate weight loss improves numerous risk factors for cardiometabolic disease; however, long-term weight loss maintenance (WLM) is often thwarted by metabolic adaptations that suppress energy expenditure and facilitate weight regain. Skeletal muscle has a prominent role in energy homeostasis; therefore, we investigated the effect of WLM and weight regain on skeletal muscle in rodents. In skeletal muscle of obesity-prone rats, WLM reduced fat oxidative capacity and downregulated genes involved in fat metabolism. Interestingly, even after weight was regained, genes involved in fat metabolism were also reduced. We then subjected mice with skeletal muscle lipoprotein lipase overexpression (mCK-hLPL), which augments fat metabolism, to WLM and weight regain and found that mCK-hLPL attenuates weight regain by potentiating energy expenditure. Irrespective of genotype, weight regain suppressed dietary fat oxidation and downregulated genes involved in fat metabolism in skeletal muscle. However, mCK-hLPL mice oxidized more fat throughout weight regain and had greater expression of genes involved in fat metabolism and lower expression of genes involved in carbohydrate metabolism during WLM and regain. In summary, these results suggest that skeletal muscle fat oxidation is reduced during WLM and regain, and therapies that improve skeletal muscle fat metabolism may attenuate rapid weight regain.  相似文献   
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