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71.
Ataç A  Guven T  Uçar M  Kir T 《Military medicine》2005,170(7):566-571
OBJECTIVE: To examine the opinions and the self-reported behaviors of physicians regarding the issues of informed consent and refusing treatment. DESIGN: This study was performed between July and September 2003, with 51 physicians selected by simple random sampling. The data were collected by using a questionnaire. SETTING: A training hospital of medicine faculty. PARTICIPANTS: Fifty-one clinicians working in the branches of internal medicine and surgery. RESULTS: Although the majority (80.4%) of the participants think that information about diagnosis and treatment should always be disclosed to patients, 60.8% reported that they always disclose information about the diagnosis and 49% did the same for information about treatment. A total of 84.3% think that patients' consent should always be obtained before diagnostic and therapeutic procedures, whereas 47% reported that they always obtain consent in their clinical practice. It was also seen that physicians have doubts concerning the comprehension of the information they disclose to their patients. In addition, most (86.3%) of the participants think that a competent patient always has the right to refuse treatment, regardless of the disease and the outcomes. CONCLUSIONS: Although opinions favoring the duties implied by informed consent are in the majority, these do not always reflect the behaviors in daily clinical practice, and there may be problems in carrying out the duties implied by the elements of informed consent. Some recommendations that could be beneficial in addressing these problems are presented at the end of the study.  相似文献   
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BACKGROUND: Several suture materials are used for pancreatojejunal anastomosis. In this study, we tested the durability of these suture materials in human pancreatic juice and bile. METHODS: Plain and chromic catgut, polyglactin 910, polyglycolic acid, polydioxanone, polypropylene, and silk sutures were incubated in pancreatic juice and bile that was collected from patients. Fifteen samples of each type of suture material were placed in human juices for 1, 3, and 7 days. Tensile strengths were measured with a tensionmeter. RESULTS: Plain and chromic catgut disintegrated in pancreatic juice and pancreatic juice plus bile mixture. Polyglycolic acid and polyglactin 910 suture materials were vulnerable to pancreatic juice within 7 days. Polydioxanone retained most of its initial strength in pancreatic juice and bile. Polypropylene and silk retained 84% and 92% of their initial strength, respectively. CONCLUSIONS: We found that polidioxanone was the strongest suture material in pancreatic juice.  相似文献   
75.
Healthy adults can swallow boluses of 20 ml water in a single swallow. Individuals with impaired swallowing, however, may be unable to do so, instead requiring two or more swallows; this phenomenon is called piecemeal deglutition. The term dysphagia limit refers to the volume at which piecemeal deglutition occurs. The aim of our study was to investigate the potential value of scintigraphic evaluation of piecemeal deglutition and dysphagia limit in patients with dysphagia, based on correlation with the results of submental electromyography (SM-EMG) and laryngeal sensor monitoring (LS). The study population comprised 24 patients with dysphagia secondary to neurological disorders and ten normal adults, who formed a control group. In the scintigraphic evaluation, subjects underwent four separate dynamic studies using 5, 10, 15 and 20 ml of water containing 0.5 mCi technetium-99m labelled sulphur colloid, and time-activity curves (TACs) were created for each study. Static thoracic images were also recorded in order to detect airway aspiration Observation of two or more peaks on TACs within the 10-s acquisition period was considered a sign of piecemeal deglutition. If piecemeal deglutition occurred at or below 20 ml, this volume was regarded as the dysphagia limit. Piecemeal deglutition was not found in any normal subjects; by contrast, it was observed in 14 of the 24 (58%) patients on scintigraphy and in 17 (71%) patients on EMG and LS. In three patients, signs of the airway aspiration were observed on static thoracic images. Scintigraphic and electrophysiological findings were in agreement in 19 patients (79%), and the correlation between scintigraphy and the electrophysiological methods for the evaluation of dysphagia was statistically significant (r=0.57, P=0.003). The novel finding of this study is the demonstration of piecemeal deglutition and dysphagia limit on scintigraphic studies in patients with neurogenic dysphagia. Based on this finding we consider that scintigraphic evaluations of piecemeal deglutition and dysphagia limit could be of value especially in centres which do not have electrophysiological test facilities. The technique should be added to the list of standard scintigraphic methods for the evaluation of patients with oropharyngeal dysphagia.  相似文献   
76.
Effects of Stamm gastrostomy on gastric emptying rate in rats   总被引:1,自引:0,他引:1  
AIM: Although frequency of gastroesophageal reflux (GER) increases after gastrostomy, the role of gastric emptying in GER has not been evaluated. In this study, we examined the effects of Stamm gastrostomy on gastric emptying rate in rats and whether Stamm gastrostomy induces GER or not. METHODS: Sprague-Dawley rats were divided into three groups. Stamm gastrostomy was done in the first group (SG). Sham operation was carried out in group 2 and the 3rd group served as control. Gastric emptying was assessed using both liquid and solid meals in each group at postoperative 14th day. For solid meal emptying, after fasting of 16 h, the rats were fed for 3 h and gastric emptying rate was measured at the fifth hour. Methylcellulose was used for emptying of liquids and it was given after the animals were fasted for 16 h and gastric emptying rate was measured 30 min later. Histological evaluation for GER was performed in all groups. RESULTS: GER was observed pathophysiologically in 5 of the 7 rats in SG group. Gastric emptying rates of liquid and solid meals were found to be similar in control, SG or sham groups. CONCLUSION: Surgical gastrostomy does not affect the gastric emptying of solid and liquid meals in rats. Other mechanisms should be considered in the development of GER observed following gastrostomy.  相似文献   
77.
BACKGROUND: Gastroduodenal ulcers are still a common cause of severe upper gastrointestinal bleeding. Endoscopy has gained popularity worldwide over conventional open surgery for the treatment of upper gastrointestinal bleeding. This study aims to assess the efficacy of endoscopic injection of epinephrine in the treatment of gastroduodenal ulcer bleeding. METHODS: This study was conducted between March 2000 and March 2003. We analyzed 107 consecutive patients admitted to our department of trauma and emergency surgery with upper gastrointestinal bleeding. Endoscopy was performed on all 107 patients and bleeding ulcers were treated with injection of diluted epinephrine. RESULTS: Recurrent bleeding was seen in 21 patients (19.6%), all of whom underwent a second endoscopy. Four patients (3.7%) required a third endoscopy session and nine patients (8.5%) needed surgery after endoscopy failed. There were two mortalities (1.9%). The nine patients who required surgery and the two patients who died were all in the Forrest Ia and Ib groups of acute UGI hemorrhage. DISCUSSION: Endoscopic injection therapy with epinephrine reduces operation rates and can be used safely in adequate hemostasis of gastroduodenal ulcers.  相似文献   
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PURPOSE: To determine the antioxidant role of vitamin E (VE) (10 mg/kg/day) against radiation-induced cataract in lens after total-cranium irradiation of rats with a single dose of 5 Gy. METHODS: Sprague-Dawley rats were divided into three groups. Group 1 did not receive VE or irradiation but received both 0.1 ml physiologic saline intraperitoneally and sham irradiation (control group). Group 2 received to total cranium 5 Gy of gamma irradiation as a single dose (RT group) plus 0.1 ml physiologic saline intraperitoneally. Group 3 received irradiation to total cranium plus 10 mg/kg/day VE (RT+VE group). The rats were irradiated using a cobalt-60 teletherapy unit. Chylack's cataract classification (1) was used in this study. At the end of 10 days, the rats were killed and their eyes were enucleated to measure the antioxidant enzymes (the activity of superoxide dismutase [SOD], glutathione peroxidase [GSH-Px]) and lipid peroxidation level (malondialdehyde [MDA]). RESULTS: While grade 1 cataract development was detectable in seven rats in the RT group, it was detectable only in two rats in the RT+VE group, whereas none of the rats in the control group exhibited any biomicroscopic change in their lenses. MDA level and GSH-Px activity in the rat lens in the RT group was significantly higher than in the control group. SOD activity in the RT group was lower than in the control group. The activity of SOD and GSH-Px enzymes was higher in the RT+VE group, but MDA level was lower in the RT+VE group when compared with the RT group. CONCLUSIONS: Vitamin E has a protective effect on radiation-induced cataract by decreasing oxidative stress.  相似文献   
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Erythropoietin and the nervous system   总被引:20,自引:0,他引:20  
Erythropoietin (Epo) is a hematopoietic growth factor and cytokine which stimulates erythropoiesis. In recent years, Epo has been shown to have important nonhematopoietic functions in the nervous system. Nonerythropoietic actions of Epo include a critical role in the development, maintenance, protection and repair of the nervous system. A wide variety of experimental studies have shown that Epo and its receptor are expressed in the nervous system and Epo exerts remarkable neuroprotection in cell culture and animal models of nervous system disorders. In this review, we summarize the current knowledge on the neurotrophic and neuroprotective properties of Epo, the mechanisms by which Epo produces neuroprotection and the signal transduction systems regulated by Epo in the nervous system.  相似文献   
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