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Since its introduction, contrast‐enhanced ultrasound (CEUS) has gained an important role in the diagnosis and management of abdominal and pelvic diseases. Contrast‐enhanced ultrasound can improve lesion detection rates as well as success rates of interventional procedures when compared to conventional ultrasound alone. Additionally, CEUS enables the interventionalist to assess the dynamic enhancement of different tissues and lesions, without the adverse effects of contrast‐enhanced computed tomography, such as exposure to ionizing radiation and nephrotoxicity from iodinated contrast material. This review article describes the various applications and advantages of the use of CEUS to enhance performance of ultrasound‐guided interventions in the abdomen and pelvis.  相似文献   
74.
A heavy metal is any relatively dense metal that may be potentially toxic in a variety of foods. Heavy metals pollute and contaminate foods. These metals are usually toxic to human body. Heavy metals are the most important toxic metals which may cause health risks following the consumption of contaminated foods. The edible salt (NaCl) is a substance that has been used as a food additive since ancient times. Twenty samples of refined and unrefined edible salts produced in Iran were analyzed using flame atomic absorption spectrometry (FAAS) method for the presence of toxic heavy metals. The precision of the analysis was assured through the repeated analysis of the samples. The mean (±standard deviation) concentrations of toxic metals in dried samples of rock salt were as follows: Ni (1.870?±?0.850), Cd (0.328?±?0.143), Mn (0.184?±?0.230) and Co (3.124?±?0.880) mg/kg and in dry weights of samples obtained from Urmia market: Ni (1.982?±?0.021), Cd (2.461?±?0.036), Mn (0.192?±?0.028) and Co (8.450?±?0.025) mg/kg. There was a significant difference between the toxic metal concentrations and their guideline values. Therefore, it was important to assess the public health risks posed by the presence of toxic contaminants.  相似文献   
75.
Neoscytalidium dimidiatum is a rare dematiaceous fungus that was first described in 1916 as Dothiorella mangiferae. From the standpoint of epidemiology and therapy, early detection of fungal rhinosinusitis (FRS), the causative agents, and their associated risk factors can improve the therapeutic outcome and decrease the mortality rates among patients. In this study, we report a 34-year-old Iranian female patient with allergic bronchopulmonary aspergillosis (ABPA), who presented to our facility with an 8-year history of chronic fungal sinusitis, drug-resistant asthma, pneumonia, bronchitis, post-nasal discharge, nasal obstruction, nasal polyposis, and anemia. The patient was subjected to diagnostic nasal endoscopy and computed tomography (CT) scan of paranasal sinuses, as well as routine, complementary mycological, and molecular methods, which confirmed the diagnosis of allergic fungal rhinosinusitis in patients with ABPA. Neoscytalidium dimidiatum was isolated from the sinus of the patient. Results of in vitro susceptibility tests indicated that the case isolate was susceptible to amphotericin B and itraconazole at concentrations which are commonly achieved in patients receiving recommended dosages for invasive mycoses (0.25 to 0.75 mg/kg of body weight daily for amphotericin B and 100 to 400 mg daily for itraconazole) and resistant in vitro to caspofungin, voriconazole, and posaconazole. The patient was successfully treated with amphotericin B / itraconazole + postoperative oral corticosteroids (OCS). Neoscytalidium dimidiatum infection should be considered as a possible additional factor in the etiology of AFRS, especially in immunocompromised patients.  相似文献   
76.
It is unclear whether bypass of a patent stented artery affects clinical outcomes. We sought to compare the survival of patients who, as part of multisystem coronary artery bypass grafting, underwent revascularization of arteries with patent stents (<50% stenosis) or in-stent restenosis (>50% diameter stenosis). Of 550 consecutive patients with previously placed stents who underwent coronary artery bypass grafting from May 1995 to October 2003, we studied 399 who had only 1 stented vessel bypassed at surgery. Of these, 128 had coronary bypass to an artery with a patent stent and 271 had bypass to an artery with in-stent restenosis. Nonparametric survival estimates were obtained using the Kaplan-Meier method. A propensity-adjusted multivariate hazard model of group differences was generated using variables identified by bootstrap bagging. The unadjusted survival rate at 1 month, 1 year, and 5 years was 99.7%, 97.3%, and 89.1%, respectively, for the patent stent group and 96.6%, 93.9%, and 86.2%, respectively, for the in-stent restenosis group, a result of high early risk in the latter group. After adjusting for clinical variables, neither stent patency (p = 0.9) nor interval (p = 0.3) from stent placement was a risk factor, although advanced age, increased blood urea nitrogen, and preoperative atrial fibrillation were associated with poorer survival. In conclusion, survival after bypassing a patent stented coronary artery is comparable to that after bypassing a stented restenotic coronary artery.  相似文献   
77.

Background:

Atherosclerotic disease is the most important cause of mortality in the world. Oxidation is an important pathway in the pathogenesis of coronary artery disease (CAD) through oxidation of low-density lipoprotein (LDL) and free radical formation. Copper (Cu) is an essential micronutrient for enzymes that catalyse LDL oxidation reactions. Therefore, an evaluation of Cu in the atherosclerotic disease is important.

Materials and Methods:

In this study, 334 subjects without recent cardiac event and history of collagen vascular or infectious disease were investigated. All patients divided into four groups to evaluate severity of CAD according to Syntax scoring system. All groups were matched in cardiovascular risk factors.

Results:

The serum level of Cu was significantly higher in total atherosclerotic groups than normal group (P value = 0.001) and significantly increased with severity of atherosclerosis.

Conclusion:

The finding indicated that the serum level of Cu is higher in atherosclerotic patients and it increases with severity of atherosclerosis. Therefore, it may be possible that the basic relationship exist between serum Cu level and atherosclerosis and an association between Cu level and severity of atherosclerosis.  相似文献   
78.
EBV‐SMT are a rare entity following organ transplantation. Given the rarity of the tumor, there is no standard approach to diagnosis and treatment. A literature search identified 28 reported cases of EBV‐SMT in addition to our own experience with one case. The aim of this review is to summarize the existing data regarding pathogenesis, diagnosis, and treatment.  相似文献   
79.
OBJECTIVE: To investigate the amount and pattern of relapse of maxillary front teeth previously retained with a bonded retainer. MATERIALS AND METHODS: The study group consisted of 135 study casts from 45 patients. Recordings from study models before treatment (T1), at debonding (T2), and 1 year after removal of the retainer (T3) were present. All patients had been treated with fixed edgewise appliances. The irregularity index (sum of contact point displacement [CPD]) and rotations of front teeth toward the raphe line were calculated at T1, T2, and T3. RESULTS: The mean irregularity index at T1 was 10.1 (range 3.0-29.9, SD 5.4). At T2 it was 0.7 (range 0.0-2.1, SD 0.7), and at T3 it was 1.4 (range 0.0-5.1, SD 1.2). Fifty-five teeth in 42 patients were corrected more than 20 degrees between T1 and T2 (mean correction 31.4 degrees range 20.0-61.7), and mean relapse in this group was 7.3 degrees (range 0.0-20.5). Regarding alignment of the maxillary front teeth, the contact relationship between the laterals and centrals seems to be the most critical. A significant positive correlation was found between the amount of correction of incisor rotation and the magnitude of relapse but not between the amount of correction of CPD and the magnitude of relapse. Eighty-four percent of the overcorrected CPDs returned to a desired position. CONCLUSIONS: Minor or no relapse was noted at the 1-year follow-up.  相似文献   
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