全文获取类型
收费全文 | 26934篇 |
免费 | 1464篇 |
国内免费 | 149篇 |
专业分类
耳鼻咽喉 | 278篇 |
儿科学 | 559篇 |
妇产科学 | 634篇 |
基础医学 | 3457篇 |
口腔科学 | 1042篇 |
临床医学 | 1938篇 |
内科学 | 7166篇 |
皮肤病学 | 916篇 |
神经病学 | 2025篇 |
特种医学 | 502篇 |
外科学 | 4379篇 |
综合类 | 174篇 |
一般理论 | 3篇 |
预防医学 | 1932篇 |
眼科学 | 442篇 |
药学 | 1471篇 |
中国医学 | 122篇 |
肿瘤学 | 1507篇 |
出版年
2023年 | 189篇 |
2022年 | 352篇 |
2021年 | 961篇 |
2020年 | 446篇 |
2019年 | 902篇 |
2018年 | 1046篇 |
2017年 | 583篇 |
2016年 | 596篇 |
2015年 | 765篇 |
2014年 | 1121篇 |
2013年 | 1400篇 |
2012年 | 2204篇 |
2011年 | 2253篇 |
2010年 | 1332篇 |
2009年 | 1164篇 |
2008年 | 1828篇 |
2007年 | 1879篇 |
2006年 | 1728篇 |
2005年 | 1537篇 |
2004年 | 1430篇 |
2003年 | 1365篇 |
2002年 | 1254篇 |
2001年 | 179篇 |
2000年 | 157篇 |
1999年 | 188篇 |
1998年 | 197篇 |
1997年 | 150篇 |
1996年 | 148篇 |
1995年 | 126篇 |
1994年 | 100篇 |
1993年 | 84篇 |
1992年 | 83篇 |
1991年 | 69篇 |
1990年 | 64篇 |
1989年 | 45篇 |
1988年 | 46篇 |
1987年 | 38篇 |
1986年 | 25篇 |
1985年 | 40篇 |
1984年 | 38篇 |
1983年 | 40篇 |
1982年 | 47篇 |
1981年 | 45篇 |
1980年 | 45篇 |
1979年 | 18篇 |
1978年 | 24篇 |
1977年 | 26篇 |
1975年 | 24篇 |
1974年 | 23篇 |
1973年 | 18篇 |
排序方式: 共有10000条查询结果,搜索用时 31 毫秒
941.
Jaime Ruiz-Tovar Lorea Zubiaga Maria Diez Ana Murcia Evangelina Boix José Luis Muñoz Carolina Llavero OBELCHE group 《Obesity surgery》2016,26(6):1221-1227
Background
Between 2 and 8 weeks before surgery, most bariatric surgery groups establish strict dietary treatments with a total caloric intake of less than 1,000 kcal/day in order to maximize weight loss during this period of time.Methods
A prospective randomized clinical trial of all the patients undergoing laparoscopic sleeve gastrectomy (LSG) was performed. Patients were randomly assigned into 3 groups: those patients receiving a preoperative regular diet of 900 kcal/day (group 1), those receiving a preoperative balanced energy high-protein formula (group 2) and those receiving preoperative Immunonutrition (group 3). Preoperative weight loss, postoperative pain, complications and analytical acute phase reactants were investigated.Results
Sixty patients were included in the study, 20 in each group. Preoperative excess weight loss was 7.7 % in group 1, 12.3 % in group 2 and 15.3 % in group 3 (p?=?0.014). Median postoperative pain was 3.5 in group 1, 3 in group 2 and 2 in group 3 (p?=?0.048). C-reactive protein determined 24 h after surgery was significantly lower in group 3 than in the other groups. AST and ALT values were significantly lower in group 3 than in the other groups, without significant differences between groups 1 and 2.Conclusions
Preoperative diet with Immunonutrition formulas during 2 weeks achieves a greater preoperative weight loss, lower postoperative pain and lower values of CRP and liver enzymes than high-protein formulas or regular diet, all of them with similar caloric intake.942.
943.
José Luis Muñoz Tanya Gabaldón Elena Miranda Diana Lorena Berrio Jaime Ruiz-Tovar José María Ronda Nuria Esteve Antonio Arroyo Ana Pérez 《Obesity surgery》2016,26(11):2648-2653
Background
In bariatric surgery, there are no guidelines available for intraoperative fluid administration. Goal-directed fluid therapy (GDFT) is a new concept of perioperative fluid management that has been shown to improve the prognosis of patients undergoing abdominal surgery. The aim of our study is to assess the impact of the implementation of a GDFT protocol in morbidly obese patients who underwent laparoscopic sleeve gastrectomy (LSG).Methods
A before-after intervention study, in morbidly obese patients who underwent LSG, was conducted at the Obesity Unit of the General University Hospital Elche. Data from the GDFT implementation group (January 2014 to December 2015) were prospectively collected and compared with a preimplementation group (January 2012 to December 2013).Results
Baseline demographic and comorbidity data between the two groups of patients were similar. The length of stay in the hospital was significantly shortened in GDFT group from 4.5 to 3.44 days (p?<?0.001). Intraoperative fluid administration was significantly lower in the GDFT group (1002.4 vs 1687.2 ml in preimplementation group, p?<?0.001). In the postoperative period, there was a statistically significant reduction in postoperative nausea and vomiting (PONV) after GDFT implementation (48 to 14.3 %, p?<?0.001).Conclusions
Implementation of GDFT protocols can prevent intraoperative fluid overload in patients undergoing bariatric surgery. It could improve outcomes, for example decreasing PONV or even hospital stay.944.
Diego García-González Verónica Murcia-Belmonte Pedro F. Esteban Felipe Ortega David Díaz Irene Sánchez-Vera Rafael Lebrón-Galán Laura Escobar-Castañondo Luis Martínez-Millán Eduardo Weruaga José Manuel García-Verdugo Benedikt Berninger Fernando de Castro 《Brain structure & function》2016,221(1):239-260
New subventricular zone (SVZ)-derived neuroblasts that migrate via the rostral migratory stream are continuously added to the olfactory bulb (OB) of the adult rodent brain. Anosmin-1 (A1) is an extracellular matrix protein that binds to FGF receptor 1 (FGFR1) to exert its biological effects. When mutated as in Kallmann syndrome patients, A1 is associated with severe OB morphogenesis defects leading to anosmia and hypogonadotropic hypogonadism. Here, we show that A1 over-expression in adult mice strongly increases proliferation in the SVZ, mainly with symmetrical divisions, and produces substantial morphological changes in the normal SVZ architecture, where we also report the presence of FGFR1 in almost all SVZ cells. Interestingly, for the first time we show FGFR1 expression in the basal body of primary cilia in neural progenitor cells. Additionally, we have found that A1 over-expression also enhances neuroblast motility, mainly through FGFR1 activity. Together, these changes lead to a selective increase in several GABAergic interneuron populations in different OB layers. These specific alterations in the OB would be sufficient to disrupt the normal processing of sensory information and consequently alter olfactory memory. In summary, this work shows that FGFR1-mediated A1 activity plays a crucial role in the continuous remodelling of the adult OB 相似文献
945.
Retrospective cohort study of prognostic factors in patients with oral cavity and oropharyngeal squamous cell carcinoma
下载免费PDF全文
![点击此处可从《Head & neck》网站下载免费的PDF全文](/ch/ext_images/free.gif)
946.
Robert J Ellis David M Small David A Vesey David W Johnson Ross Francis Luis Vitetta Glenda C Gobe Christudas Morais 《Nephrology (Carlton, Vic.)》2016,21(3):170-177
In the last decade, chronic kidney disease (CKD), defined as reduced renal function (glomerular filtration rate (GFR) < 60 mL/min per 1.73 m2) and/or evidence of kidney damage (typically manifested as albuminuria) for at least 3 months, has become one of the fastest‐growing public health concerns worldwide. CKD is characterized by reduced clearance and increased serum accumulation of metabolic waste products (uremic retention solutes). At least 152 uremic retention solutes have been reported. This review focuses on indoxyl sulphate (IS), a protein‐bound, tryptophan‐derived metabolite that is generated by intestinal micro‐organisms (microbiota). Animal studies have demonstrated an association between IS accumulation and increased fibrosis, and oxidative stress. This has been mirrored by in vitro studies, many of which report cytotoxic effects in kidney proximal tubular cells following IS exposure. Clinical studies have associated IS accumulation with deleterious effects, such as kidney functional decline and adverse cardiovascular events, although causality has not been conclusively established. The aims of this review are to: (i) establish factors associated with increased serum accumulation of IS; (ii) report effects of IS accumulation in clinical studies; (iii) critique the reported effects of IS in the kidney, when administered both in vivo and in vitro; and (iv) summarize both established and hypothetical therapeutic options for reducing serum IS or antagonizing its reported downstream effects in the kidney. 相似文献
947.
948.
949.
AIMS: To describe 13 examples of clear cell dermal duct tumour, a neoplasm previously underrecognized in the literature. METHODS AND RESULTS: Thirteen examples of a neoplasm that we have named clear-cell dermal duct tumour were studied histopathologically and immunohistochemically. Histopathologically, all lesions consisted of mostly dermal neoplasms mainly composed of multiple solid aggregations of clear cells involving the dermis. Although the neoplasms were mostly solid, ductal structures were identified in all cases. Immunohistochemically, neoplastic cells were immunoreactive for MNF116 and AE1/AE3 cytokeratins, but not for CAM5.2 or cytokeratin 7. Epithelial membrane antigen, carcinoembryonic antigen and glial cystic disease fibrillary protein 15 decorated the ductal structures, but neoplastic cells were negative. In contrast to some other clear cell neoplasms of the skin, which may be associated with diabetes mellitus, none of our cases of clear cell dermal duct tumour developed in a diabetic patient. CONCLUSIONS: We consider these neoplasms to be clear cell dermal duct tumours for the following reasons: (i) the neoplasms were mostly composed of multiple solid aggregations of epithelial clear cells; (ii) neoplastic aggregations mostly involved the dermis; (iii) in some cases, neoplastic aggregations of conventional poroid cells were intermingled with the aggregations of clear cells; (iv) ductal structures were identified within some neoplastic aggregations; (iv) small areas of necrosis en masse were seen in some neoplastic aggregations; and (v) the stroma of the neoplasm was scant. 相似文献
950.
Spindle cell and epithelioid cell differentiation occur in both benign and malignant hyperpigmented melanocytic lesions. Reed nevus is characterized by compact, sharply circumscribed junctional cellular nests composed of slender hyperpigmented melanocytes shaped like spindle cells. Deep penetrating nevus is characterized by a diffuse dermal proliferation composed of small nests and fascicles of pale ovoid and epithelioid melanocytes. Cellular blue nevi often have a characteristic hourglass or dumbbell shape, with sharply circumscribed elongated nests and fascicles of pale, densely layered ovoid melanocytes and adjacent melanophages. Epithelioid blue nevus is characterized by large epithelioid melanocytes with abundant cytoplasm and melanin often concentrated to some degree in the cell membrane. Animal-type melanoma is a particularly hyperpigmented variant of melanoma in which large melanophages predominate and there are varying proportions of melamin-rich spindle-shaped and large atypical epithelioid melanocytes. Morphologically, pigmented epithelioid melanocytoma combines characteristics of both animal-type melanoma and pigmented epithelioid nevus. Malignant melanoma may occur in conjunction with a preexistent blue nevus. Malignant blue nevus is now regarded as a malignant melanoma mimicking a blue nevus in structure and pattern. It is therefore of paramount importance to view multiple mitoses within a cellular blue nevus-like proliferation as an alarm signal as they are usually indicators of a malignant melanoma. 相似文献