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51.
Purpose To investigate the effect of N-acetylcysteine on preventing pump-induced oxidoinflammatory response during cardiopulmonary bypass (CPB).Methods Forty patients undergoing coronary artery bypass grafting (CABG) were randomly divided into a study group (n = 20), given 50mgkg–1 N-acetylcysteine intravenously for 3 days, and a control group (n = 20) given saline. Serum samples were collected for measurement of myeloperoxidase (MPO), malondialdehyde (MDA), interleukin-6, 1-acid glycoprotein (AAGP), and C-reactive protein (CRP) during surgery and postoperatively.Results The MPO and MDA values showed a similar pattern during and after CPB in the study group, with significantly less variance than in the control group. Interleukin-6 showed similar patterns in the two groups, but the data from 30min after the start of CPB and from 6h post-CPB were significantly different. The AAGP and CRP values were both elevated during CPB in the two groups without a significant difference, but 6 and 24h post-CPB, the values were significantly higher in the control group than in the study group.Conclusions N-Acetylcysteine decreased pump-induced oxidoinflammatory response during CPB, suggesting that it could be a novel therapy for assisting in the prevention of CBP-induced oxidoinflammatory damage.  相似文献   
52.
BACKGROUND AND AIMS: Long-term smoking increases the risk of renal diseases and it also causes the progression of the diseases. The aim of this study was to evaluate the effects of smoking on glomeruli in healthy rats exposed to long-term passive smoking for a short period of time after birth. METHODS: Sixty-five rats were randomly assigned into four groups. Groups 1 (18 males) and 2 (18 females) were exposed to smoke, whereas groups 3 (15 males) and 4 (14 females) were not exposed to smoke. Overall, 130 renal units were evaluated, and diameters of 10 different glomeruli were measured. The renal and bodyweights of the rats were measured. RESULTS: The diameter of the glomeruli was 95.51 +/- 9.25 and 100.91 +/- 4.06 microm in groups 1 and 3, respectively (P < 0.05). It was 97.32 +/- 4.06 and 98.86 +/- 6.25 microm in groups 2 and 4, respectively (P > 0.05). Irrespective of the sex, the diameter of the glomeruli was 96.42 +/- 7.15 microm in smokers and 99.92 +/- 5.56 microm in non-smokers (P < 0.05). The renal weights of the male rats affected by smoke were significantly lower than that of those that were not affected by smoke (P < 0.05). Bodyweights of male rats affected by smoke were significantly lower that of those not affected (P < 0.05). There was a weak correlation between the diameter of the glomeruli and the bodyweights of male rats affected by smoke (r = 0.474, P < 0.05). CONCLUSION: We conclude that passive smoking might have a negative affect on renal morphometry and body growth.  相似文献   
53.
54.
The present study was carried out to evaluate the effects of 1alpha,25-dihydroxyvitamin D3 (VD) on chromosomal aberrations induced by doxorubicin (DXR). Wistar rats were divided into eight experimental groups of five animals each. Control group animals were treated with i.p. distilled water. The animals in three VD groups were given only VD for 4, 6 or 8 weeks. In the DXR groups the animals were given only DXR. In the combination groups VD doses were given for 4, 6 or 8 weeks for each group and DXR was injected 24 h before sacrificing the rats. DXR (50 mg/100 g b.w.) was injected intraperitoneally and VD by gavage 3 microg/kg/day twice weekly. Animals treated with both VD and DXR showed a low frequency of chromosomal aberrations and abnormal metaphases when compared with animals treated with DXR alone (p < 0.0001). The numbers of both chromosomal aberrations and abnormal metaphases were similar in weeks 6 and 8 (p > 0.05) and lower than those in week 4 for the VD groups (p < 0.0001). Under the present experimental conditions, the efficiency of VD in protecting cells against DXR-induced chromosome damage was found to be dose dependent. The protective effects of VD on chromosome aberrations induced by DXR are discussed in the light of literature data.  相似文献   
55.
This retrospective analysis was performed to examine the outcome of patients with spinal cord ependymomas treated with surgery and postoperative radiation therapy between 1982 and 1998. There were 10 male and 5 female patients, ranging from 16 to 74 years of age with a median age of 38 years. Surgery was gross total resection in 2 patients, subtotal resection in 10, biopsy in 3. All patients received radiation therapy with a total dose of 40-56 Gy. The 5 and 10 year overall survival rates were 83.3 and 83.3%, respectively. Twelve patients are still alive at a median follow-up period of 70 months. Of the 15 patients, 6 developed recurrent disease on follow-up. The median time to recurrence was 45 months (range: 24-80 months). Local failure within the initial irradiated volume occurred in 3 out of 6 patients who received less than 45 Gy and 2 out of 8 patients treated with more than 45 Gy. Four out of the six failures were salvaged with additional treatment. Re-irradiation was used as a part of salvage or sole treatment in 3 cases. The patient who was salvaged with radiation therapy only died of disease progression 41 months following recurrence and the other two who received a combination of surgery, radiotherapy or chemotherapy were still alive 57 and 30 months following relapse. The present study shows that surgery and post-operative radiation treatment for spinal ependymoma patients resulted in high survival rates. Patients with residual disease after surgery should be treated with radiation therapy with a dose of more than 45 Gy. Re-irradiation may be the treatment of choice for recurrent patients having less than complete resection or no surgery.  相似文献   
56.
Orbital roof fractures are uncommon, and traumatic intraorbital encephalocele formation is a very rare complication of this type of injury. We treated 43 pediatric patients with orbital roof fractures at our center over a 4-year period. The aim of this study was to retrospectively investigate conditions that may lead to intraorbital encephalocele formation in children with orbital roof fractures. Each case was reviewed, and the cause of injury, associated clinical and computerized tomography findings, the Glasgow Coma Scale score on admission, neurological status, other bodily injuries, hospitalization time and type and width of the orbital roof fracture were recorded. The findings in 6 patients who developed encephaloceles were compared to corresponding findings in the 37 patients who did not develop this complication. A total of 44 orbital roof fractures were diagnosed by axial and coronal computed tomography scanning. Six of the 43 children developed intraorbital encephaloceles in the first month after head trauma. In each of these cases, magnetic resonance imaging demonstrated the intraorbital cystic lesion in communication with the subarachnoid space. The width of each orbital roof fracture was measured on axial and coronal computed tomography slices and was confirmed by measurements during surgery. The width of the fractures in the encephalocele cases ranged from 2-4 mm. Duraplasty and orbitoplasty were performed in all the patients with encephalocele. Pediatric patients with orbital roof fractures that exhibit more than 2 mm diastasis and are associated with frontal cerebral contusion may be at greater risk for developing intraorbital encephalocele. All such cases should be monitored closely and investigated further with magnetic resonance imaging.  相似文献   
57.
Spinal cord injury with or without trauma has been reported in the perinatal period. The prognosis depends primarily on diagnosis of the level, extent and nature of the lesion, established by correlations between clinical, imaging and electrophysiological data. A 25-day-old boy with normal birth weight delivered at term by cesarean section was transferred to In?nü University Turgut Ozal Medical Center because of respiratory distress and brachial diplegia. A suspicious medullary lesion on cervical computerized tomography was confirmed as an intramedullary lesion extending from C3 to D1 on magnetic resonance imaging (MRI). Emergent surgery consisting of exposure of the lesion site and interlaminar direct puncture of the lesion under fluoroscopy revealed that the pathology was an intramedullary hematoma. The partial evacuation of the lesion with direct puncture, the patient's neurological improvement and close follow-up of the patient with ultrasonography, electrophysiology and MRI are discussed in the light of recent literature.  相似文献   
58.
 The purpose of this study was to investigate the associations of tooth loss with skeletal bone mass, years since menopause, educational level, current smoking status, dietary calcium intake, and number of pregnancies in postmenopausal osteoporotic women in Turkey. The study population consisted of 1171 postmenopausal women aged 40–86 years (mean age, 61.19 ± 7.28 years). A detailed history was obtained from all women, including relevant lifestyle parameters, risk factors, and measurements of weight and height. Women were separated into three groups according to the number of teeth remaining as group 1 (edentulous, 457 women), group 2 (10 or fewer teeth, 232 women), and group 3 (more than 10 teeth remaining, 482 women). There was no significant difference among the three groups in mean age and menopausal age (P < 0.05). Body mass index of group 1 was significantly higher than that of group 2 (P < 0.01). Educational level was significantly different between three groups: groups 1 and 2 (P < 0.001), groups 1 and 3 (P < 0.0001), and groups 2 and 3 (P < 0.001). Educational level was lowest in group 1 and highest in group 3. Despite a low ratio of cigarette smoking in general, a smoking habit was most prevalent in group 3 and least in group 2. The ratio of women receiving adequate calcium was significantly lower in group 1 than in other groups (P < 0.001); mean calcium intake was similar in all groups. The number of pregnancies was significantly higher in group 1 than in other groups (P < 0.001). Lumbar bone mineral density (BMD) of group 1 was significantly lower than that of groups 2 and 3 (P < 0.001). Although no significant difference was found between groups 1 and 3, femoral neck BMD of group 2 was less than in others, and differences between groups 1 and 2 and between groups 2 and 3 (P < 0.001) were significant. Lumbar bone mineral content (BMC) of group 1 was significantly lower than that of groups 2 and 3 (P < 0.001), and lumbar BMC in group 2 was significantly higher than in group 3 (P < 0.05). Femoral neck BMC in group 1 was significantly higher than in groups 2 and 3 (P < 0.001). In conclusion, lumbar BMD and BMC in the edentulous group were significantly lower, whereas femoral neck BMD and BMC were significantly higher in edentulous group compared with the others. Our findings indicated that improvement in lifestyle factors and nutritional strategies for the treatment and prevention of osteoporosis may have additional benefit in reducing tooth loss. Received: February 18, 2002 / Accepted: June 21, 2002 Offprint requests to: A. Gur  相似文献   
59.
PURPOSE: New contact lens materials with high oxygen permeability are said to be convenient for the extended-wear (EW) schedule. We evaluated the short-term effect of EW soft contact lens usage on ocular surface and central corneal thickness. PATIENTS AND METHODS: Fifty-two eyes of 26 patients were included in the study. Sixteen of the patients used the high oxygen-permeable lenses for a 30-day extended-wear schedule (group I). Ten patients used the lenses on a daily wear basis (DW, group II). All patients were evaluated for visual acuity and central corneal thickness by corneal and conjunctival biomicroscopy, Schirmer and tear break-up time (BUT) tests. Impression cytology was performed in the superior/temporal, inferior/nasal quadrants of the conjunctiva, 1 mm from the limbus, with cellulose acetate filter paper. The specimens were graded under light microscopy according to Nelson's classification. RESULTS: Three patients in the EW group were excluded from the study as they discontinued lens usage due to slight discomfort and hyperemia. Biomicroscopic findings and tear function tests indicated no increased pathological results. Central corneal thickness decreased from 554 +/- 9.55 to 546 +/- 9.30 microm (mean +/- SEM) in the EW group (p = 0.002), whereas no significant change occurred in the DW group. Cytological evaluation of the EW group showed an 88% increase in metaplasia (p = 0.007), especially close to the limbal areas and in the superior quadrants; this ratio was 30% in the DW group. Snake-like chromatin changes were found to be increased, from 4 to 6 patients, in the EW group while it remained the same in the DW group (p > 0.05). Individual comparisons of the initial and final pathological conditions of the ocular surfaces in the two groups showed that there was an increase in pathology in the EW group while there was no significant difference in the DW group. CONCLUSIONS: On a 30-day extended-wear basis with high oxygen-permeable lenses, the possible development and increase of conjunctival cytologic changes secondary to mechanical trauma is one of the main remaining problems. Conjunctival and related immunologic pathologies should not be overlooked when prescribing an extended-wear lens schedule.  相似文献   
60.
PURPOSE: To report a case of Purtscher-like retinopathy after weightlifting. METHODS: A 17-year-old man presented with a sudden visual loss in his left eye after weightlifting two weeks ago. Fundus examination of the left eye showed cotton-wool spots and scattered retinal hemorrhages in the posterior pole. Fluorescein angiography and indocyanine green angiography with a scanning laser ophthalmoscope were performed. RESULTS: Angiography showed hypofluorescent areas adjacent to the optic disc and in the posterior pole and partial filling insufficiency in the inferior and inferotemporal branch retinal veins. Complete venous filling was noted in late phases of angiography. CONCLUSIONS: The pathogenesis of weightlifting suggests the Purtscher-like changes as a result of Valsalva maneuver in our case. To our knowledge, this is the first reported case of Purtscher-like retinopathy associated with weightlifting.  相似文献   
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