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31.
OBJECTIVES: This study evaluated the role of circulating tissue factor (TF) in mediating thrombus formation on stents in an in vitro model of stent perfusion. BACKGROUND: The traditional view of coagulation has recently been challenged by the demonstration that TF is present in circulating blood. The potential contribution of this intravascular pool of TF to thrombus formation on stents is not known. METHODS: Coronary stents were placed in parallel silicone tubes connected to a roller pump that was set to pump blood at a flow rate of 10 ml/min. Stents were then exposed to heparinized blood from healthy volunteers for 120 min. RESULTS: The presence of the stent in the circuit caused a significant increase in monocyte TF expression, but only monocytes with attached platelets stained positive for TF. Thrombi formed on stents and the thrombi stained positive for TF. Pretreatment of blood with a monoclonal antibody against TF (cH36) caused a 56% reduction in (125)I-fibrin(ogen) deposition on stents compared with controls (p = 0.002). Monocyte depletion of blood reduced (125)I-fibrin(ogen) deposition by 45% (p = 0.01) and TF staining in the thrombus by 83% (p = 0.01). Pretreatment of blood with a monoclonal antibody against P-selectin reduced (125)I-fibrin(ogen) deposition by 24% (p = 0.04). Perfusion of stents with leukocyte-reduced platelet-rich plasma (PRP) produced small thrombi and treatment of PRP with cH36 reduced (125)I-fibrin(ogen) deposition by 43% (p = 0.01). CONCLUSIONS: Circulating TF plays a pivotal role in thrombus formation on stents. Monocytes appear to be the main, but not only, source of TF depositing in the thrombus.  相似文献   
32.
Patent foramen ovale as a risk factor for cryptogenic stroke.   总被引:14,自引:0,他引:14  
OBJECTIVE: To determine and compare the prevalence of patent foramen ovale in patients with stroke of undetermined origin (cryptogenic) and in patients with stroke of determined origin to assess the possible role of patent foramen ovale as a risk factor for cryptogenic stroke. DESIGN: Cross-sectional study with nested case-control analysis. PATIENTS: A total of 146 patients (73 men, 73 women) with acute ischemic stroke referred to the echocardiography laboratory for evaluation. SETTING: Neurovascular Unit and Echocardiography Laboratory, Columbia-Presbyterian Medical Center, New York, New York. MEASUREMENTS: Patients were considered to have strokes of determined origin or cryptogenic strokes according to National Institute of Neurological Disorders and Stroke (NINDS) Stroke Data Bank criteria. The presence of patent foramen ovale was assessed by contrast echocardiography, performed blinded for type of stroke. The association between patent foramen ovale and type of stroke was tested after correcting for patients' demographic variables and stroke risk factors. RESULTS: The overall prevalence of patent foramen ovale was 26 of 146 patients (18%; 95% Cl, 11.4% to 24.6%). Patients with cryptogenic stroke (31%) had a significantly higher prevalence of patent foramen ovale than did patients with an identifiable cause of stroke (69%) in both the younger (less than 55 years; 48% compared with 4%; P less than 0.001) and the older (greater than or equal to 55 years; 38% compared with 8%; P less than 0.001) age groups. Multiple logistic regression analysis was used to identify the presence of a patent foramen ovale as strongly associated with the diagnosis of cryptogenic stroke (odds ratio, 7.2; Cl, 2.4 to 21.7), irrespective of patient age and other stroke risk factors. CONCLUSIONS: Patients with cryptogenic stroke have a higher prevalence of patent foramen ovale than patients with stroke of determined cause in all age groups, even after correcting for the presence of recognized stroke risk factors. This identifies patent foramen ovale as a risk factor for cryptogenic stroke. Regardless of patient age, contrast echocardiography should be considered when the cause of stroke is unknown.  相似文献   
33.
Several hepatobiliary complications secondary to gastrointestinal perforation after ingestion of a fish bone have been described in the literature, the most common being liver abscess, which can be potentially fatal. Treatment involves removal of the foreign body if possible (endoscopically or surgically), drainage of the abscess (radiologically or surgically), and appropriate antibiotic therapy. To our knowledge, no cases of hepatic hilar abscesses secondary to gastrointestinal perforation by a fish bone have been described in the literature. We report surgical management of two cases of abscess localized in the hepatic hilum secondary to the ingestion of fish bones.  相似文献   
34.
Small cell carcinoma of the ovary, hypercalcemic type (SCCOHT) is a rare and aggressive condition that is associated with the SMARCA4 mutation and has a dismal prognosis. It is generally diagnosed in young women. Here, we report a case of a young woman with SCCOHT harboring a rare molecular finding with a highly aggressive biological behavior. The patient had a somatic SMARCB1 mutation instead of an expected SMARCA4 alteration. Even though the patient was treated with high-dose chemotherapy followed by stem cell transplantation, she evolved with disease progression and died 11 months after her first symptoms appeared. We present a literature review of this rare disease and discuss the findings in the present patient in comparison to expected molecular alterations and options for SCCOHT treatment.  相似文献   
35.
36.
BACKGROUND The impact of obesity on surgical outcomes in elderly patients candidate for liver surgery is still debated.AIM To evaluate the impact of high body mass index(BMI) on perioperative and oncological outcome in elderly patients(> 70 years old) treated with laparoscopic liver resection for hepatocellular carcinoma(HCC).METHODS Retrospective multicenter study including 224 elderly patients(> 70 years old) operated by laparoscopy for HCC(196 with a BMI < 30 and 28 with BMI ≥ 30), o...  相似文献   
37.
38.
Title.  Tobacco smoking habits among nursing students and the influence of family and peer smoking behaviour.
Aim.  This paper is a report of a study assessing tobacco smoking habits among nursing students and how these are influenced by family members and peers.
Background.  Tobacco smoking among nursing students is a serious problem because of the public role model of these future healthcare professionals.
Methods.  The smoking attitude of nursing students attending the 3 year full-time course at the University of Milan in the academic years 2006–2007 and 2007–2008 was investigated. A total of 820 students filled in the self-administered questionnaire and 812 valid questionnaires were returned. The response rate was 87%.
Results.  Forty-four percent of the 812 students were tobacco smokers and 7% former smokers. Among the smoking students 75% had at least one smoking parent, 47% had at least one smoking brother or sister and 87% saw smoking friends.
Conclusion.  There is an urgent need to implement effective anti-smoking measures among nursing students. Decreasing the number of smokers among healthcare professionals would discourage people from smoking and would increase the credibility of anti-smoking campaigns.  相似文献   
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40.
Twenty-three prepubertal subjects treated for Wilms' tumor (10 males and 13 females) were endocrinologically evaluated off therapy from 0.5 to 4.08 years. They were divided into two groups: 11 subjects (6M, 5F) who had received chemotherapy only (group 1) and 12 (4M, 8F) who had in addition received abdominal radiation (1,500-3,000 rads) (group 2). Follicle-stimulating hormone (FSH), luteinizing hormone (LH), prolactin (PRL), thyroid-stimulating hormone (TSH), free thyroxine (FT4), free tri-iodo thyronine (FT3), testosterone (T), estradiol-17 beta (E2), and cortisol (F) were measured by radioimmunoassay (RIA). Plasma levels of TSH, PRL, FT4, FT3, and F were normal in both groups, as were FSH, LH, T, and E2 in group 1. In group 2, female subjects showed FSH levels significantly higher than controls, while LH and E2 were normal; male subjects showed significantly higher LH levels, while FSH and T levels were normal. These results indicate that in the treatment protocol used by us for Wilms' tumor (WT), chemotherapy does not affect endocrine function, whereas abdominal radiation seems to damage gonadal function directly. The present findings indicate that gonadal damage may be revealed in WT before puberty not only in females, as has been previously reported, but also in male subjects.  相似文献   
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