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61.
The aim of the present study is to evaluate the effect of swallowing type (dry versus wet) on the outcome of a nine-step inflation/deflation tympanometric Eustachian tube function (ETF) test in healthy adults. Fourteen normal healthy volunteers, between 19 and 28 years of age, were included in the study. The nine-step test was performed in two different test procedures: (1) test with dry swallows (dry test procedure) and (2) test with liquid swallows (wet test procedure). If the equilibration of middle-ear (ME) pressure was successful in all the steps of the nine-step test, ETF was considered 'Good'. Otherwise, the test was considered 'Poor', and the test was repeated at a second session. In the dry test procedure, ETF was 'Good' in 21 ears at the first session and in 24 ears after the second session (p > 0.05). However, in the wet test procedure, ETF was 'Good' in 13 ears at the first session and in 21 ears after the second session (p < 0.05). At the first session, ETF was 'Good' in 21 and 13 ears in the dry and wet test procedures, respectively. The difference was statistically significant (p < 0.05). However, after the second session, the overall number of ears with 'Good' tubal function was almost the same in both test procedures (24 ears at dry test procedures versus 21 ears at wet test procedures;p > 0.05). Dry swallowing seems to be more effective for the equilibration of ME pressure. Thus, a single-session dependent evaluation of ETF may be efficient for the dry test procedure of the nine-step test. Swallowing with water may be easier for subjects, but a repetition of the test at a second session may be necessary when the test result is 'Poor'.  相似文献   
62.
Recent studies suggest that 3-hydroxy-3 methylglutaryl coenzyme A (HMG-CoA) reductase inhibitors, statins, can have direct effects on blood vessels beyond their cholesterol-lowering effects. We investigated the effects of atorvastatin on the functional and structural properties of blood-brain barrier (BBB) and the activity of astrocytes during the N(omega)-nitro-L-arginine methyl ester (L-NAME) hypertension followed by angiotensin (ANG) II. We found that decreases in concentration of serum catalase and plasma nitric oxide (NO) induced by L-NAME were significantly ameliorated by atorvastatin, whereas L-NAME-induced serum malondialdehyde and cholesterol concentration increases were significantly reduced by atorvastatin. The content of Evans blue (EB) dye significantly increased in cerebellum, left cerebral cortex and diencephalon regions but atorvastatin markedly reduced the increased BBB permeability to EB in the brain regions of animals treated with L-NAME and L-NAME plus ANG II. Brain vessels of L-NAME-treated animals showed a considerable loss of immunoreactivity of tight junction proteins, zonula occludens (ZO)-1 and occludin. Immunoreactivity for ZO-1 and occludin increased in animals treated with atorvastatin and L-NAME plus atorvastatin. Glial fibrillary acidic protein (GFAP) immunoreactivity was seen in few astrocytes in the brain sections of L-NAME, but immunoreactivity for GFAP increased in L-NAME plus atorvastatin-treated animals. We suggest that long-term L-NAME treatment may affect BBB permeability through disruption of tight junction proteins, at least partly, via decreased NO concentration and increased oxidant capacity; the improvement of BBB integrity and astrocytic activity would be more closely associated with the action of atorvastatin favoring the increase in anti-oxidant capacity and expression of tight junction proteins and GFAP.  相似文献   
63.
OBJECTIVE: Our aim was to determine whether inward or outward movement of the secretions in the paranasal sinuses due to nose blowing after nasal decongestion has any effect on the paranasal sinus computed tomography (CT) images in patients with sinusitis and to asses whether nose blowing may result in misdiagnosis or overdiagnosis in radiological evaluation of sinusitis. MATERIALS AND METHODS: Twenty-four patients with chronic sinusitis were evaluated in an academic tertiary care hospital and data were collected prospectively. After coronal sinus computed tomography scans were performed at 100 mA setting which was half the value of the standard radiation dose suggested by the manufacturer, topical decongestion was applied to each nostril followed by nose blowing 10 min later. Sinus CT scans were then repeated at the same setting. We evaluated the mucosal thickness of medial, lateral, superior and inferior maxillary and frontal sinus walls and the maximal thickness in anterior ethmoidal cells. The measurements prior to and following nose blowing were compared with Wilcoxon signed ranks test. The obtained images were also staged using Lund-McKay staging system separately and the scores were compared with Student's t-test. RESULTS: We observed a tendency towards reduction in mucosal thickness after nose blowing. There were statistically significant differences between maxillary sinus inferior wall and frontal sinus inferior wall mucosal thickness values prior to and after nose blowing. The difference however was very small, about 0.5 mm in magnitude and Lund-McKay score did not change in any of the patients after nose blowing. CONCLUSION: Nose blowing and topical nasal decongestion does not have any effect on the diagnostic accuracy of sinus CT in chronic sinusitis patients.  相似文献   
64.
In this article, a Wohlfahrtia magnifica otomyiasis case, a 31-year-old, non-mentally retarded patient who had undergone radical mastoidectomy previously is presented. Maggots in the radical mastoidectomy cavity were removed then topical treatment was applied. The maggots were identified as W. magnifica. In cases of myiasis, identification of larvae following direct extraction and application of preventative methods is essential.  相似文献   
65.
OBJECTIVE: The purpose of this study was to determine plasma malondialdehyde (MDA), superoxide dismutase (SOD), soluble E-selectin (sE-selectin), fibronectin, endothelin-1 (ET-1) and nitric oxide (NO) levels in women with preeclampsia and to find out the relations of diastolic blood pressure with these variables. STUDY DESIGN: We performed a case-control study consisting of randomly selected 34 healthy pregnant women and 35 patients diagnosed as preeclampsia. Lipoperoxidation was ascertained by the formation of MDA. SOD activity was determined by the method of Sun et al. Plasma concentration of NO was estimated using colorimetric assay. Plasma ET-1 and sE-selectin were measured by enzyme-linked immunosorbent assay (ELISA). A nephelometric method for fibronectin quantitation was used. RESULTS: The mean plasma level of MDA was significantly higher and SOD was significantly lower in preeclamptic pregnancies (P<0.001). Plasma concentrations of fibronectin, sE-selectin and ET-1 were significantly increased, whereas NO was significantly decreased in women with preeclampsia than normotensive women (P<0.001). CONCLUSION: Increased plasma levels of MDA, fibronectin, sE-selectin, ET-1, and decreased plasma levels of NO and SOD in preeclamptic patients suggest that poorly perfused fetoplacental unit is the origin of oxygen free radicals and lipid peroxides.  相似文献   
66.
BACKGROUND AND OBJECTIVE: To compare the effects of sevoflurane and desflurane anaesthesia on lipid peroxidation. METHODS: We studied 40 healthy patients undergoing elective laparoscopic cholecystectomy. Patients were randomly allocated to be anaesthetized either with sevoflurane (n = 20) or desflurane (n = 20). Anaesthesia was maintained with inspiratory concentrations of sevoflurane 1-1.5 MAC (n = 20) or desflurane (n = 20). Samples were taken for plasma malondialdehyde and superoxide dismutase assays before induction of anaesthesia, before skin incision and at the end of surgery. Alveolar cell samples were obtained from the lungs using the technique of protective blind bronchoalveolar lavage, after induction of anaesthesia and at the end of surgery for malondialdehyde and superoxide dismutase concentrations. RESULTS: Plasma malondialdehyde increased more after the administration of desflurane than after sevoflurane: after induction 5.9 +/- 0.6 nmol mL(-1) for desflurane vs. 3.8 +/- 0.5 nmol L(-1) for sevoflurane (P < 0.001); at the end of the surgery: 6.7 +/- 0.4 nmol mL(-1) for desflurane vs. 4.2 +/- 0.3 nmol mL(-1) for sevoflurane (P < 0.001). There was a small but significant increase in plasma superoxide dismutase concentration after desflurane--from 24.2 +/- 1.2 to 24.9 +/- 0.9 U mL(-1) after induction and 25 +/- 1 U mL(-1) at the end of the surgery (P < 0.01)--but no increase with sevoflurane. Malondialdehyde concentrations increased significantly in the cells obtained by protective blind bronchoalveolar lavage at the end of surgery in the desflurane group (from 0.3 +/- 0.1 to 1.7 +/- 0.2 nmol mL(-1) (P < 0.001)), but not in the sevoflurane group. There were no significant differences between the two anaesthetics in the amounts of superoxide dismutase in the samples obtained by protective blind bronchoalveolar lavage. CONCLUSIONS: Desflurane may cause more systemic and regional lipid peroxidation than sevoflurane during laparoscopic cholecystectomy in healthy human beings.  相似文献   
67.
OBJECTIVES: It is well documented that children, particularly between the ages of about 2 and 6 years, exhibit a high prevalence and incidence of otitis media. Distortion product otoacoustic emissions (DPOAEs) offer great potential for clinical testing of cochlear function in children. The aim of the present study was to determine the influence of middle ear effusion and physical properties of the effusion on the recording of DPOAE. METHODS: Nineteen children (38 ears) undergoing myringotomy and/or tympanostomy tube insertion for secretory otitis media were studied. Pre-operative and post-operative first day DPOAE signal to noise ratios were compared. The results were analyzed by paired samples test and ANOVA statistical methods. RESULTS: We were found significant differences between pre-operative and post-operative first day DPOAE signal to noise at 1, 1.5, 2 and 4kHz. In addition, comparison of the pre-operative DPOAE signal to noise ratio and per-operative middle ear findings are shown significant differences between glue (thick mucous) and the other three groups (mucous, serous and no-effusion groups) at 2 and 4kHz, and between glue and no effusion group at 8kHz. Also post-operative DPOAE signal to noise ratio in relation to per-operative middle ear findings were significantly different at 2, 4 and 8kHz. The most increase of emissions at the post-operative first day was seen in ears with glue effusion at 1 and 2kHz. CONCLUSIONS: Otitis media with effusion can be monitored by DPOAE measurement pre-operatively and post-operatively. In the pre-operative evaluation, glue effusion may cause a reduction in the emissions at 2, 4 and 8kHz more than the other kind effusions.  相似文献   
68.
OBJECTIVE: To evaluate by computed tomographic scanning the paranasal mucosal changes of coal workers with and without pneumoconiosis. METHODS: Examination of images and scores from paranasal computed tomographic scans. The study participants were 26 coal workers with pneumoconiosis, 29 coal workers without pneumoconiosis, and 20 controls. All were men. The extent and patterns of inflammatory paranasal sinus disease were evaluated on computed tomographic scans by 2 radiologists using the terminology and definitions of Newman and associates. RESULTS: Interobserver agreement for the presence of abnormalities was from good to excellent (kappa, 0.63-0.89). The mucosal scores of individuals and groups were higher for coal workers than for control subjects. Both scores were significantly higher in the pneumoconiosis group than in the 2 other groups. CONCLUSIONS: This study shows that paranasal sinuses were affected more severely in coal workers than in control subjects. In coal workers with pneumoconiosis, the affection was most severe. The relationship between coal dust exposure and paranasal mucosal changes needs further study.  相似文献   
69.
OBJECTIVE: To investigate the plasma and placental levels of interleukin-10 (IL-10), transforming growth factor-beta1 (TGF-beta1), and epithelial-cadherin (E-cadherin) in normotensive and preeclamptic pregnancies. METHODS: The study population consisted of 33 women with normotensive pregnancy and 35 women with preeclampsia. Peripheral venous blood samples were collected before labor (35.3 +/- 1.1 and 34.2 +/- 3.4 weeks' gestation for normotensive and preeclamptic pregnancies, respectively), and placental tissues were obtained after delivery. Maternal plasma and placental homogenate IL-10, TGF-beta1, and E-cadherin levels were determined by enzyme-linked immunosorbent assay. RESULTS: The mean plasma and placental levels of IL-10, TGF-beta1, and E-cadherin were significantly higher in preeclamptic than normotensive patients (P <.001). The plasma and placental levels of IL-10, TGF-beta1, and E-cadherin significantly increased with the increments in diastolic blood pressure (P <.001). CONCLUSION: IL-10, TGF-beta1, and E-cadherin may be involved in the pathologic process of preeclampsia. The pathophysiologic changes associated with preeclampsia may stem in part from the overproduction of these placental mediators.  相似文献   
70.
The possible cochlear toxicity of systemically applied macrolides--erythromycin (ER), azithromycin (AZ) and clarithromycin(CL)--was investigated in guinea pigs by measuring transiently evoked otoacoustic emissions (TEOAEs). A single dose of 125 mg/kg intravenous (i.v.) ER caused no change in TEOAEs in guinea pigs (p>0.05), whereas AZ (45 mg/kg orally) and CL (75 mg/kg i.v.) reversibly reduced the emission response (p<0.05). The reversible reduction of TEOAE responses due to AZ and CL, which is in accordance with the clinical picture of AZ and CL ototoxicity, could likely be attributable to the transient dysfunction of outer hair cells. The present study reveals that at least one ototoxic effect of AZ and CL is on the inner ear. The results may also encourage planning clinical researches on TEOAE monitoring in patients receiving high doses of AZ or CL.  相似文献   
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