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21.
OBJECTIVES: We aimed to find the frequency of otolith organ pathologies in the clinical picture of common dizziness etiologies in the chronic stage. METHOD: Subjective visual vertical and subjective visual horizontal measures were assessed in patients who had persistent or recurrent dizziness at least 2 months after the acute period. Every patient was tested in three head positions: neutral, right, or left deviation in the roll plane. Test results were compared with those of the control group. RESULTS: Seventy-three patients and 18 controls were examined. Fifty-eight of the patients had peripheral vestibular disease; 15 of them had central vestibular disease. Left subjective visual horizontal (SVH) and right SVH measures of the peripheral group were significantly different from those of the control group (p < .01). There was no difference in any test between the peripheral and central groups. When we put a cut off point for abnormality (0, 1) according to mean +/- 2 SD of the control group, the peripheral and central groups had very high significant differences from the control group. Approximately 25 to 50% of our patients had pathologic subjective visual vertical or SVH measures according to test type. CONCLUSION: These results showed that the otolith system must be evaluated in the chronic period of dizziness, especially in patients who frequently visit their physician, and modifications in treatment programs must be conducted.  相似文献   
22.
PURPOSE: To compare diffusion-weighted echo-planar imaging (DW) with spin-echo (SE), and fluid-attenuated inversion recovery (FLAIR) sequences in the evaluation of epidermoid cysts (ECs), and to evaluate T2 shine-through effect. MATERIALS AND METHODS: Fifteen patients were imaged prospectively in two different 1.5 T magnetic resonance (MR) units with standard head coils with SE, FLAIR and DW echo planar imaging sequences. The qualitative and quantitative assessments were performed by two radiologists in consensus. Apparent diffusion coefficient (ADC) values were obtained from all ECs. Exponential DW images are obtained in 11 cases to eliminate T2 shine-through effects. The results are analyzed with variance analysis (ANOVA) and Bonferroni t method. RESULTS: FLAIR sequence was superior to T1- and T2-weighted sequences in showing ECs. In 13 cases, the borders of the lesions could be delineated from the surrounding structures with only DW imaging where ECs were markedly hyperintense. The ADC values of ECs are significantly lower than CSF (P < 0.001), and significantly higher than deep white matter (P < 0.01). On exponential DW images, ECs had similar intensity with brain parenchyma showing that the real cause of the hyperintensity of the lesions on trace images is the enhanced T2 effect of the tissue. CONCLUSION: FLAIR sequence is superior to the conventional MR sequences in demonstrating the ECs and DW imaging is superior to other MR sequences in delineating the borders of the ECs. Exponential DW images had shown that the hyperintensity in the trace images are caused by increased T2 effect of the lesion rather than the decrease in ADC values.  相似文献   
23.
Caudal ropivacaine and neostigmine in pediatric surgery   总被引:6,自引:0,他引:6  
BACKGROUND: Neostigmine has been added to local anesthetics for different nerve blocks. This study was conducted to evaluate effects of neostigmine when added to ropivacaine for caudal anesthesia. METHODS: We studied children, aged 1-5 yr, undergoing inguinal hernia and hypospadias surgery. After standard induction of anesthesia, Group I received 0.2% ropivacaine 0.5 ml/kg and Group II received 0.2% ropivacaine 0.5 ml/kg with 2 microg/kg neostigmine via the caudal route. Heart rate, mean arterial pressure, and pulse oximetry were recorded before induction, after induction, and then every 10 min after caudal anesthesia. Hemodynamic, Toddler-Preschooler Postoperative Pain Scale pain score, and sedation score values were recorded 30 min after extubation and at hours 2, 4, 6, 12, and 24. A pain score greater than 3/10 resulted in administration of rectal paracetamol. RESULTS: There were no differences between the groups in demographic and hemodynamic data, duration of surgery and anesthesia, time to extubation, or sedation scores. The pain scores were significantly lower in Group II at 6 and 12 h (P < 0.05). Time to first analgesic requirement was statistically prolonged in Group II (19.2 +/- 5.5h) when compared with Group I (7.1 +/- 5.7 h) (P < 0.05). Total analgesic consumption was statistically larger in Group I (174 +/- 96 mg) when compared with Group II (80 +/- 85.5 mg) (P < 0.05). The incidence of vomiting (3 patients in Group II and 1 patient in Group I) was not statistically significantly different. CONCLUSIONS: The authors found that a single caudal injection of neostigmine when added to ropivacaine offers an advantage over ropivacaine alone for postoperative pain relief in children undergoing genitourinary surgery.  相似文献   
24.
OBJECTIVE: To evaluate the hemodynamic changes in mild-moderate preeclampsia using ophthalmic artery Doppler ultrasonography technique. METHODS: Ophthalmic artery pulsatility and resistivity indices were calculated in 30 mild-moderate preeclamptic women and 30 normotensive gravid women of matched gestational age. Student's t-test was performed to test the significance of difference. RESULTS: Both indices of peripheral resistance were found to be significantly lower in the ophthalmic arteries of mild-moderately preeclamptic women than those measured in normotensive gravid women at similar stage of pregnancy. In a small number patients whose disease progressed to severe preeclampsia, both indices increased. CONCLUSION: In patients with mild-moderate preeclampsia, ophthalmic artery color Doppler ultrasonography detects hemodynamic changes that are not present in normotensive gravid women. Reversal of Doppler patterns in a small number of patients with progressive disease supports the hypotheses suggesting the presence of early vasodilation and late vasospasm in the etiology of preeclampsia.  相似文献   
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26.
BACKGROUND: Patients with asthma incur the risk of steroid-induced myopathy, which is a well-known side effect of treatment with corticosteroids. However, the adverse effect of long-term steroid treatment on respiratory muscle function remains controversial. OBJECTIVE: We aimed to evaluate the effects of long-term moderate dose of systemic corticosteroids and high-dose inhaled beclomethasone on maximal inspiratory and expiratory pressures (PImax and PEmax, respectively) in two groups of asthmatic patients exhibiting comparable levels of hyperinflation. METHODS: Twelve steroid-dependent asthmatic patients requiring 10-20 mg/day of prednisone-equivalent corticosteroids for an average of 9.83 +/- (SD) 9.86 years; 14 subjects with moderate to severe asthma who have used inhaled beclomethasone for at least 1 year at a daily dose higher than 1,000 microg and 15 healthy controls were included to the study. RESULTS: No significant difference in pulmonary function tests and arterial blood gases appeared between two asthmatic groups with different treatment modalities. PImax as an absolute value was significantly lower in steroid-dependent asthmatics than in patients treated with inhaled beclomethasone and controls (p < 0.01). %PImax was also lower in steroid-dependent asthmatics than in control groups (p < 0.01). A significant correlation was found between %PImax and hyperinflation assessed by %RV, %FRC, %FRC/TLC (p < 0.05) in all asthmatic patients. CONCLUSIONS: We believe that hyperinflation plays a major role in inspiratory muscle dysfunction in asthma, but the finding of significantly decreased PImax values in steroid-dependent asthmatics when compared with patients on high-dose inhaled beclomethasone with a comparable level of hyperinflation points to a deleterious effect of long-term, moderate-dose systemic corticosteroid but not high-dose beclomethasone on inspiratory muscle function in asthmatics.  相似文献   
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28.
The aim of this study was to evaluate the effects of tamoxifen on tumor necrosis factor α (TNF-α) and interleukin 1β (IL-1β) levels and ultrastructural changes in rats with spinal cord injury. Rats were divided into four groups: control group (laminectomy only), trauma group (laminectomy + spinal trauma), tamoxifen group (laminectomy + spinal trauma + tamoxifen), and vehicle group (laminectomy + spinal trauma + vehicle). Spinal cords were extirpated at the T7–T12 level and tissue samples from the spinal cords were gathered for TNF-α and IL-1β measurements at 1 and 6 hours. Spinal cords harvested at 6 hours were evaluated for ultrastructural changes. TNF-α and IL-1β levels at 6 hours were significantly lower in the tamoxifen group than in the trauma group. Electron microscopic examination of tissue from the trauma group revealed gross cell deformities with widespread edema of all structures as well as severe edema in the neuropil. At 6 hours after trauma, these ultrastructural changes were less marked in the tamoxifen group. Our findings support a neuroprotective and restorative role for tamoxifen in the context of secondary pathological biochemical events after SCI.  相似文献   
29.
BackgroundOsteoblasts and osteoclasts are known to express Ang II type I (AT1) receptor in cell cultures, suggesting the existence of local renin-angiotensin system (RAS) in bone. This study was designed to investigate the effects of losartan as AT1 receptor blocker on ovariectomized rats' femur.MethodsLosartan (5 mg/kg/day) was administered via oral gavage for 8 weeks. Bone mineral density (BMD) was measured using dual energy X-ray absorptiometry, while tensile and three-point bending tests were performed for evaluation of biomechanical properties of bone. The trabecular porosity was analyzed by scanning electron microscopy.ResultsThere was a significant decrease in BMD values of ovariectomized rats' femurs which were reversed by losartan treatment. According to tensile test results, ultimate tensile strength and strain values of losartan treated ovariectomized rats' femurs increased and decreased, respectively, when compared to that of ovariectomized animals. Losartan treatment also caused a significant recovery in flexural strength and modulus parameters regarding respective control values, which mean losartan treated ovariectomized rats' femur had more force tolerance until break than ovariectomized rats' femur. Quantitative microscopic analysis showed larger trabecular porosity in ovariectomized rats than control rat femurs and it was significantly decreased after losartan treatment.ConclusionBlockage of AT1 receptor increased strength, mass and trabecular connections of ovariectomized rat femurs. Therefore, it is tempting to speculate that drugs, including AT1 receptor blockers, may be used for the treatment of osteoporosis or reduction of its detrimental effects in the future.  相似文献   
30.
OBJECTIVE: The aim of this study was to investigate the effect of the radiological evidence of emphysema, and the extent of interstitial involvement, on lung function and pulmonary arterial pressure (PAP) in patients with coal workers' pneumoconiosis (CWP). METHODS: The records of 48 patients with suspected CWP were evaluated retrospectively. Pulmonary function tests, arterial blood gas analyses and right heart catheterization were evaluated in all patients. Radiological scoring was according to International Labour Organization criteria, and emphysema was scored by CT scanning. Patients were grouped according to the mean PAP (> or =20 mm Hg or < or =19 mm Hg). RESULTS: All patients showed a mild decrease in FEV(1)/FVC and a mild increase in FRC. Forty-four per cent of patients developed mild to moderate pulmonary hypertension. Emphysema scores correlated significantly with airflow rates, including FEV(1)%, FEV(1)/FVC and FEF(25-75%), and with carbon monoxide diffusing capacity (DLCO)% predicted as well as FRC% predicted and the ratio RV/TLC, which are indices of air trapping. Additionally, profusion and global profusion scores showed significant correlation with FEV(1)/FVC, DLCO% predicted, specific airway conductance and smoking. Mean PAP showed a significant negative correlation with FEF(50%) predicted, DLCO% predicted and profusion score. CONCLUSIONS: The impairment of pulmonary function (mainly disturbance in airflow rates and air trapping) and pulmonary hypertension may be present, even in a simple form of CWP. The pulmonary function impairment in patients with CWP is likely to be attributable to the occurrence of emphysema. However, pulmonary hypertension was directly related to the profusion of pneumoconiotic nodules, which may result in obliteration of the vascular bed.  相似文献   
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