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111.
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PURPOSE: Current estimates of the proportion of cancer patients who will require RT are based almost entirely on expert opinion. The objective of this study was to estimate the proportion of incident cases of colorectal cancer that should receive RT using an evidence-based approach. METHODS AND MATERIALS: A systematic review of the literature was undertaken to identify indications for RT for colorectal cancer, and to ascertain the level of evidence that supported each indication. An epidemiologic approach was then used to estimate the incidence of each indication for RT in a typical North American population of colorectal cancer patients. The effect of sampling error on the estimated appropriate rate of RT was calculated mathematically, and the effect of systematic error was estimated by sensitivity analysis. RESULTS: It was estimated that 23.7% +/- 1.0% of colorectal cancer cases develop one or more indications for RT at some point in the course of the illness: 20.9% +/- 1.1% as part of their initial treatment, and 2.8% +/- 0.5% later for recurrence or progression. We estimated that 7.1% +/- 0.8% of colon carcinoma patients will require RT at some point in the course of the illness: 4.0% +/- 0.7% as part of their initial treatment, and 3.1% +/- 0.4% later for recurrence or progression. We estimated that 72.3% +/- 1.0% of rectal carcinoma patients will require RT at some point in the course of the illness: 69.6% +/- 0.9% as part of their initial treatment and 2.7% +/- 0.2% later for recurrence or progression. CONCLUSIONS: This method provides a rational starting point for the long-term planning of radiation services, and for the audit of access to RT at the population level. By completing such evaluations in the major cancer sites, it will be possible to estimate the appropriate RT treatment rate for the cancer population as a whole.  相似文献   
113.
High performance liquid chromatographic (HPLC) techniques for the quantification of 5-fluorouracil (5-FU) in human plasma have been reported in the literature, however, a low limit of detection was generally found to result in a comparatively low extraction yield. We have developed a simple, rapid and sensitive HPLC method for the measurement of 5-FU in plasma which provides both a low limit of quantification and a high extraction yield. This method involves the solid phase extraction of 5-FU from a 500 microl plasma sample. The extract is then injected into an HPLC system equipped with a C18 (mu)Bondapak column, and a UV detector set at 260 nm. Ethyl acetate and potassium dihydrogen phosphate are used for the solid phase extraction and the HPLC mobile phase, respectively. This method provides in a good baseline, a sharp and symmetrical peak for 5-FU, and a high resolution between 5-FU and the internal standard. The retention time of 5-FU using this method is 4.7 min with a limit of detection of 5 ng/ml, and an extraction yield of 96.2+/-0.5% (SE). The next injection is possible in 11 min, and the coefficients of variation are 4.2-8.9% for interday precision, and 5.2-10.6% for day-to-day reproducibility. An HPLC method has been developed that has a low limit of detection and a high extraction yield. This technique was successfully applied in a clinical pharmacokinetic study of 5-FU.  相似文献   
114.
BACKGROUND: It is important to distinguish between responders to standard treatment and non-responders Hodgkin's disease (HD) patients. PATIENTS AND METHODS: Between June 2003-September 2004, in our institute, 40 newly-diagnosed patients with advanced stage HD were consecutively treated with ABVD chemotherapy for six cycles. All these patients underwent staging/restaging: computed tomography (CT) and positron emission tomography (PET) at time 0, PET after two cycles, CT and PET after four and six cycles. RESULTS: After two cycles (PET-2), the PET was negative in 28/40 (70%), positive in 8/40 (20%), and minimal residual uptake (MRU) was present in the remaining four (10%) patients. After treatment, among eight patients who were PET-2+, seven showed refractory disease and one had relapse after 3 months. All four patients with MRU at the PET-2 became PET- during the further four cycles and, after treatment, three were in complete response (CR) and one relapsed after 5 months. All 28 PET negative patients at the PET-2 remained PET negative and all of them were in CR after treatment. CONCLUSIONS: The PET use for early (after two cycles) response assessment in HD patients is a significant step forward and has the potential to help physicians make crucial decisions about further treatment.  相似文献   
115.
Background/aim Frailty is associated with an increased risk of negative short-term and long-term hospital outcomes. This study aimed to evaluate the role of frailty in predicting readmission, length of stay, and quality of life in the hospitalized older adults.Materials and methods This observational study was conducted at Ziaiyan Hospital, Tehran, Iran. In total, 304 participants (65–85 years), were enrolled through the inclusion criteria from August to December 2019. The frailty index (FI) was assessed by the minimum data set-home care. Readmission was obtained through telephone interviews. The length of stay was gathered by the patient’s hospital records, and the EuroQol questionnaire was used for assessing the quality of life. Data were collected by a researcher nurse at the admission time, 30, 60, and 90 days after discharge. The logistic regression model and repeated measures ANOVA were employed to analyze the association between frailty and outcomes.ResultsAccording to FI, 102 (33.55%) participants were pre-frail, whereas 35 (11.51%) were frail. In the fully-adjusted model for readmission, the pre-frail participants had a higher risk of readmission at the hospital in comparison with the nonfrail and frail groups (OR = 1.88, 95% CI = 1.90–3.26), and also for GP visits, frail patients showed nearly significant differences (OR = 2.45, 95% CI = 0.99–6.06) but there were no differences between frail and pre-frail patients in readmissions in the emergency ward. In a fully-adjusted prolonged stay model, pre-frail patients had a higher probability to stay longer in hospital (OR = 2.28, 95% CI: 1.24–4.18). The fully-adjusted model for QoL showed, frail patients were more prone to the declined levels of QoL in comparison with pre-frail patients (OR = 10.77, 95% CI: 3.97–29.18).ConclusionsThe findings indicated that frailty worsened negative outcomes and declined QoL. Early diagnosis in hospital settings could be beneficial for designing optimal care plans for the frail and pre-frail patients.  相似文献   
116.
BACKGROUND: Dieulafoy's lesion is a vascular malformation, usually of the stomach but occasionally of the small or large bowel. It is an uncommon, but clinically significant, source of upper gastrointestinal hemorrhage. Three cases have been reported in the literature of laparoscopic gastric wedge resection of these lesions by using intraoperative endoscopic localization. We present the only reported case of preoperative endoscopic localization of a Dieulafoy's lesion with India ink and an endoscopic clip before laparoscopic resection. CASE REPORT: We present an 82-year-old female patient who presented to the emergency department with 3 episodes of hematemesis. Esophagogastroduodenoscopy revealed an actively bleeding Dieulafoy's lesion in the fundus of the stomach along the greater curvature, which was controlled endoscopically. However, the patient had a recurrent episode of bleeding. Repeat endoscopy was performed and the lesion was tagged with 2 endoscopic clips and marked with India ink. A laparoscopic wedge resection was performed after the India ink was identified in the fundus. The patient did well postoperatively. CONCLUSION: Preoperative localization of a Dieulafoy's lesion with India ink and endoscopic clips before laparoscopic wedge resection is a feasible procedure. Therefore, no need exists for intraoperative endoscopy to aid in the localization, as previously reported.  相似文献   
117.

Background  

The objective of this study was to estimate the burden of disease and injury in Iran for the year 2003, using Disability-Adjusted Life Years (DALYs) at the national level and for six selected provinces.  相似文献   
118.
BACKGROUND: The collagen vascular diseases are a collection of conditions, which are thought to be secondary to pathologic alterations in the immune system. Deposition of immune complexes in blood vessel walls resulting in either ischemia or thrombosis is the most widely accepted pathologic mechanism. The lack of familiarity with this subgroup of disease can lead to unnecessary surgical intervention. DATA SOURCES: A Medline search was performed of all the English-language literature. Further references were obtained through cross-referencing the bibliography cited in each work. CONCLUSION: Clinical manifestations are varied and complications include constipation, fecal incontinence, pseudoobstruction, perforation, hemorrhage, and mesenteric ischemia. Colorectal manifestations typically follow dermal presentations. Management should be conservative especially for pseudo-obstructions. Surgical intervention increases morbidity and should be chosen when absolutely necessary. Because of the high incidence of colorectal malignancies in patients with dermatomyositis, aggressive screening should be performed.  相似文献   
119.
STUDY OBJECTIVES: To investigate the effect of high-dose vitamin C on cytochrome P450 (CYP) 3A4 activity, and to evaluate possible sex-specific effects on CYP3A4 activity. DESIGN: Single-center longitudinal study. SETTING: Tertiary- and specialty-care teaching hospital. SUBJECTS: Fourteen healthy Caucasian adult volunteers (seven men, seven women). INTERVENTION: Subjects self-administered vitamin C 500 mg twice/day for 14 days. MEASUREMENTS AND MAIN RESULTS: Hepatic CYP3A4 activity was measured by using the erythromycin breath test on days 1 (baseline) and 15. Overall, no significant effect of vitamin C on CYP3A4 activity was observed. Sex and baseline results were significant predictors of changes in CYP3A4 activity. In men, mean activity increased by 21.9% (95% confidence interval -3.88-47.6%). The effect in women was not consistent. CONCLUSION: Sex and baseline CYP3A4 activity appeared to influence the effect of vitamin C on CYP3A4 activity.  相似文献   
120.
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