全文获取类型
收费全文 | 3665篇 |
免费 | 189篇 |
国内免费 | 24篇 |
专业分类
耳鼻咽喉 | 77篇 |
儿科学 | 69篇 |
妇产科学 | 80篇 |
基础医学 | 472篇 |
口腔科学 | 67篇 |
临床医学 | 342篇 |
内科学 | 909篇 |
皮肤病学 | 24篇 |
神经病学 | 639篇 |
特种医学 | 118篇 |
外科学 | 387篇 |
综合类 | 8篇 |
一般理论 | 2篇 |
预防医学 | 167篇 |
眼科学 | 35篇 |
药学 | 214篇 |
中国医学 | 15篇 |
肿瘤学 | 253篇 |
出版年
2023年 | 26篇 |
2022年 | 55篇 |
2021年 | 91篇 |
2020年 | 60篇 |
2019年 | 83篇 |
2018年 | 102篇 |
2017年 | 74篇 |
2016年 | 109篇 |
2015年 | 100篇 |
2014年 | 148篇 |
2013年 | 182篇 |
2012年 | 276篇 |
2011年 | 241篇 |
2010年 | 152篇 |
2009年 | 144篇 |
2008年 | 251篇 |
2007年 | 247篇 |
2006年 | 240篇 |
2005年 | 254篇 |
2004年 | 223篇 |
2003年 | 196篇 |
2002年 | 194篇 |
2001年 | 33篇 |
2000年 | 19篇 |
1999年 | 27篇 |
1998年 | 56篇 |
1997年 | 30篇 |
1996年 | 16篇 |
1995年 | 32篇 |
1994年 | 19篇 |
1993年 | 19篇 |
1992年 | 15篇 |
1991年 | 9篇 |
1990年 | 16篇 |
1989年 | 12篇 |
1988年 | 8篇 |
1987年 | 10篇 |
1986年 | 11篇 |
1985年 | 12篇 |
1984年 | 13篇 |
1983年 | 7篇 |
1982年 | 15篇 |
1981年 | 5篇 |
1980年 | 9篇 |
1979年 | 5篇 |
1978年 | 3篇 |
1976年 | 3篇 |
1974年 | 8篇 |
1973年 | 4篇 |
1970年 | 4篇 |
排序方式: 共有3878条查询结果,搜索用时 31 毫秒
81.
Abstract Currently available anticoagulants are effective in reducing the recurrence rate of venous thromboembolism (VTE). However,
anticoagulant treatment is associated with an increased risk for bleeding complications. Thus, anticoagulation has to be discontinued
when benefit of treatment no longer clearly outweigh its risks. The duration of anticoagulant treatment is currently framed
based on the estimated individual risk for recurrent VTE. The incidence of recurrent VTE can be estimated through a two-step
decision algorithm. Firstly, the features of the patient (gender), of the initial event (proximal or distal deep vein thrombosis
or pulmonary embolism), and the associated conditions (cancer, surgery, etc) provide essential information on the risk for
recurrence after anticoagulant treatment discontinuation. Secondly, at time of anticoagulant treatment discontinuation, d-dimer levels and residual thrombosis have been indicated as predictors of recurrent VTE. Current evidence suggests that the
risk of recurrence after stopping therapy is largely determined by whether the acute episode of VTE has been effectively treated
and by the patient’s intrinsic risk of having a new episode of VTE. All patients with acute VTE should receive oral anticoagulant
treatment for three months. At the end of this treatment period, physicians should decide for withdrawal or indefinite anticoagulation.
Based on intrinsic patient’s risk for recurrent VTE and for bleeding complications and on patient preference, selected patients
could be allocated to indefinite treatment with VKA with scheduled periodic re-assessment of the benefit from extending anticoagulation.
Alternative strategies for secondary prevention of VTE to be used after conventional anticoagulation are currently under evaluation.
Cancer patients should receive low molecular-weight heparin over warfarin in the long-term treatment of VTE. These patients
should be considered for extended anticoagulation at least until resolution of underlying disease.
Abbreviated abstract The risk for recurrent venous thromboembolism can be estimated through a two-step algorithm. Firstly, the features of the
patient (gender), of the initial event (proximal or distal deep vein thrombosis or pulmonary embolism), and the associated
conditions (cancer, surgery, etc) are essential to estimate the risk for recurrence after anticoagulant treatment discontinuation.
Secondly, a correlation has been shown between d-dimer levels and residual thrombosis at time of anticoagulant treatment discontinuation and the risk of recurrence. Currently
available anticoagulants are effective in reducing the incidence of recurrent venous thromboembolism, but they are associated
with an increased risk for bleeding complications. All patients with acute venous thromboembolism should receive oral anticoagulant
treatment for three months. At the end of this treatment period physicians should decide for definitive withdrawal or indefinite
anticoagulation with scheduled periodic re-assessment of the benefit from extending anticoagulation. 相似文献
82.
Novelli G Rossi M Pretagostini R Poli L Novelli L Berloco P Ferretti G Iappelli M Cortesini R 《Liver》2002,22(Z2):43-47
As reported in the literature, the mortality rates for patients with Acute Hepatic Failure (AHF) approaches 80% in cases in which liver transplantation is not possible. Post-transplant mortality mostly depends on the severity of the neurological condition at the time of the operation (20% in I-II degree coma patients and 44% in III degree coma patients). The primary indications for liver transplantation in AHF are Fulminant Hepatitis (FH)(93%), Subfulminant Hepatitis (5%) and other indications (2%). Other causes of AHF are Primary Non-Function (PNF) and Delayed Function (DF), which occur in 7-10%. Therefore it becomes necessary to monitor the patients with a Liver Support Device to be able to improve the clinical condition of the patients before liver transplantation (LT). In our experience we used the Molecular Adsorbent Recirculating System (MARS) (MARS Monitor; Teraklin AG, Rostock Germany), which enables the selective removal of albumin-bound substances accumulating in liver failure by the use of albumin-enriched dialysate. The system is used as a bridging device to orthotopic liver transplantation (OLT) of patients with FHF. We studied 34 patients, including 16 males and 18 females: 9 were affected by Primary-Non-Function (PNF), nine by Fulminant Hepatitis (FH), six by Delayed-Non-Function (DNF), and ten by Acute on Chronic Hepatic Failure (AOCHF). The average age of the patients was 41.8 years and the average number of applications was 6.4; the median length of application was about eight hours. The parameters that we monitored, before and after each treatment, were neurological status (EEG, cerebral CT, Glasgow Coma Score), haemodynamic parameters, acid base equilibrium, and blood gas analysis. We also monitored hepatic and renal function. In addition, the clinical conditions of the patients were monitored using kidney and liver ultrasound/ultrasonography (US). Inclusion criteria were bilirubin > 15 mg/dL, ammonia > 160 micro g/dL and a Glasgow Coma Score between 6 and 11. The reduction of bilirubin and ammonia were very significant (P < 0.01), whereas the changes of International Normalized Ratio (INR) were not significant. Also the modifications of albumin, total protein, sodium, potassium and calcium were not significant. In conclusion, four out of nine patients with PNF are alive without a second transplantation and were discharged after about 48 days; four out of nine underwent OLT, while one out of nine died; five out of six patients with DF are alive without a second transplantation, and they were discharged after an average time of 55.5 days, one out of six died; six out of nine patients with fulminant hepatitis underwent OLT and four of these are alive, while two died due to sepsis; three patients are alive without OLT. Four patients with AOCHF underwent OLT and are alive, three patients are alive and on a waiting list, two died while on a waiting list and one patient who experienced reactivation of HBV infection during chemotherapy for non-Hodgkin's lymphoma is alive. In spite of the limited number of cases of our study, we believe that MARS can be applied with high tolerance for a very long period of time. In addition, its repeatability allows it to be used in patients with DNF and FH as a bridge to transplant. In patients with DNF, it is used while waiting for complete recovery of the transplanted organ. 相似文献
83.
Alberto Berardi Claudio Gallo Licia Lugli Isotta Guidotti Giancarlo Gargano Livia Maccio 《The journal of maternal-fetal & neonatal medicine》2015,28(14):1694-1696
Neonatal Herpes simplex virus (HSV) pneumonia without apparent accompanying disseminated infection is a rare condition. We describe a case of neonatal pneumonia following maternal HSV type 1 viraemia in late pregnancy. A review of the literature shows that cases of HSV presenting as pneumonia in the first week of life are the most severe form of neonatal HSV. 相似文献
84.
Surface Chemistry of Amphiphilic Polysiloxane/Triethyleneglycol‐Modified Poly(pentafluorostyrene) Block Copolymer Films Before and After Water Immersion 下载免费PDF全文
Elisa Martinelli Gabriele Pelusio Bhaskar R. Yasani Antonella Glisenti Giancarlo Galli 《Macromolecular chemistry and physics.》2015,216(21):2086-2094
New amphiphilic block copolymers Si‐EFSx composed of a poly(dimethyl siloxane) (Si) block and a poly(4‐(triethyleneglycol monomethyl ether)‐2,3,5,6‐tetrafluorostyrene) (EFS) block are synthesized by atom transfer radical polymerization (ATRP) starting from a bromo‐terminated Si macroinitiator. Similarly, new hydrophobic block copolymers Si‐FSy consisting of an Si block and a poly(pentafluorostyrene) (FS) block are prepared for comparison. X‐ray photoelectron spectroscopy (XPS) analysis on block copolymer films reveals that the Si block is concentrated at the polymer–air interface, while the EFS block is located in the layers underneath. The same polymer films undergo a marked surface reconstruction after immersion in water for 7 d, as probed by XPS. This phenomenon involves the exposure of the hydrophilic oxyethylenic chains to contact water. Such surface reconstruction is even more drastic when an amphiphilic block copolymer is dispersed in a cross‐linked poly(dimethyl siloxane) matrix film.
85.
Peter Ong Giancarlo Pirozzolo Anastasios Athanasiadis Udo Sechtem 《Clinical therapeutics》2018,40(9):1584-1590
Purpose
Coronary spasm is frequently found in patients with angina and unobstructed coronaries. The pathophysiology is incompletely understood, although sex differences have been described. Often a positive family history (PFH) is encountered. We assessed the relationship between sex, coronary spasm, and a PFH for cardiovascular disease.Methods
This single-center observational study recruited 415 stable angina patients with unobstructed coronaries (no stenosis >50%) between 2008 and 2011 (mean [SD] age, 62 [10] years; 38% men). Patients were referred for angiography because of signs and symptoms of myocardial ischemia. Intracoronary acetylcholine (ACh) testing was performed in all patients according to a standardized protocol. Risk factor assessment included hypertension, hypercholesterolemia, diabetes, smoking, and a PFH. The latter was defined as a first-degree relative with myocardial infarction or stroke. Statistical analysis involved comparison of categorical and continuous variables. Multivariable analysis aimed at identifying predictors for a pathologic ACh testing, microvascular spasm, and a PFH.Findings
Epicardial spasm was found in 33% of patients and microvascular spasm in 30% of patients. A pathologic ACh test was more frequent in women than in men (72% vs 49%; P < 0.0005). A PFH was found in 55% of patients with significantly more women than men (61% vs 45%; P?=?0.001). Among patients with epicardial spasm, women had a PFH significantly more often than men (66% vs 43%; P?=?0.006). The latter difference was not found when comparing women and men with microvascular spasm.Implications
There is a female preponderance among patients with angina and unobstructed coronaries. ACh testing enables detection of coronary spasm. Epicardial spasm in women is associated with a PFH. 相似文献86.
Maurizio Varanini Rita Balocchi Giancarlo Carli Giulia Paoletti Enrica L. Santarcangelo 《The International journal of clinical and experimental hypnosis》2018,66(3):265-281
The study investigated whether the cardiac activity and cognitive–emotional traits sustained by the behavioral inhibition/activation system (BIS/BAS) may contribute to hypnotizability-related pain modulation. Nociceptive stimulation (cold-pressor test) was administered to healthy participants with high (highs) and low (lows) hypnotizability in the presence and absence of suggestions for analgesia. Results showed that heart rate increased abruptly at the beginning of nociceptive stimulation in all participants. Then, only in highs heart rate decreased for the entire duration of hand immersion. During stimulation with suggestions of analgesia, pain threshold negatively correlated with heart rate. BIS/BAS activity partially accounted for the observed hypnotizability-related differences in the relation between cardiac interoception and pain experience. 相似文献
87.
88.
Luciano Magalhães Vitorino Laryssa Souza Marins Alessandra Lamas Granero Lucchetti Ana Eliza Oliveira Santos Jonas Preposi Cruz Paulo José Oliveira Cortez Giancarlo Lucchetti 《Geriatric nursing (New York, N.Y.)》2018,39(1):48-53
This aim of this study was assess whether positive and negative spiritual/religious coping (SRC) strategies are associated with depressive symptoms (DS) of informal caregiver (IC) of hospitalized older adults. A cross-sectional study was conducted among 98 IC of hospitalized older adults in the medical clinic of a Brazilian School Hospital. The functionality, Positive and Negative SRC strategies and DS were evaluated. The IC had high average use of SRC, with Positive SRC being more used than Negative SRC. In the unadjusted regression model, Positive and Negative SRC were associated with DS. However, when adjusted for confounding factors, only Negative SRC remained associated with DS. The IC had used their religious and spiritual beliefs as a way to cope with the stress that comes from caring for hospitalized older adults. Although the positive strategy use of these beliefs was more common, only the negative strategies were associated with a higher DS. 相似文献
89.
Togliani Thomas Pilati Stefano Lisotti Andrea Caletti Giancarlo Fusaroli Pietro 《Abdominal imaging》2018,43(11):2987-2990
Abdominal Radiology - Post-surgical upper gastrointestinal anatomy may hamper a complete bilio-pancreatic evaluation with a standard echoendoscope. The aim of this study was to assess the role of... 相似文献
90.
Giancarlo Cicolini Carlo Della Pelle Valentina Simonetti Dania Comparcini Gianna Sepede Francesco Cipollone 《Archives of Psychiatric Nursing》2018,32(2):305-309