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81.

Background

The aim of this study was to investigate the ability of a SERM, RLX, to prevent vasospasm in a rabbit model of SAH.

Methods

Thirty-four New Zealand white rabbits were allocated into 3 groups randomly. Subarachnoid hemorrhage was induced by injecting autologous blood into the cisterna magna. The treatment groups were as follows: (1) sham operated (no SAH [n = 12]), (2) SAH only (n = 12), and (3) SAH plus RLX (n = 10). Basilar artery lumen areas and arterial wall thickness were measured to assess vasospams in all groups.

Results

There was a statistically significant difference between the mean basilar artery cross-sectional areas and the mean arterial wall thickness measurements of the control and SAH-only groups (P < .05). The difference between the mean basilar artery cross-sectional areas and the mean arterial wall thickness measurements in the RLX-treated group was statistically significant (P < .05). The difference between the SAH group and the SAH + RLX group was also statistically significant (P < .05).

Conclusions

These findings demonstrate that RLX has marked vasodilatatory effect in an experimental model of SAH in rabbits. This observation may have clinical implications suggesting that this SERM drug could be used as possible anti-vasospastic agent in patients without major adverse effects.  相似文献   
82.
ObjectiveBoth diabetes and hemodialysis (HD) are associated with increased oxidative stress. The aim of this study was to clarify the effect of maintenance HD on oxidative stress parameters in diabetic patients and to explore any relation between carotid artery intima-media thickness (CIMT) and oxidative stress markers.MethodsTwenty Type 2 diabetic patients undergoing chronic maintenance HD, 20 type 2 diabetic patients with normal renal function, and 20 age- and sex-matched healthy subjects were included. Serum thiobarbituric acid reactive substances (TBARS), protein carbonyl content (PCO), and nitrite/nitrate levels were determined as oxidative stress markers. Serum vitamin E, plasma sulfhydryl (P-SH), erythrocyte glutathione (GSH) levels, and superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GPx) activities were measured as antioxidants. CIMT was assessed by carotid artery ultrasonography.ResultsBoth diabetic patient groups had enhanced oxidative stress indicated by higher levels of TBARS, PCO, and nitrate/nitrite and lower activities of SOD, CAT, and GPx compared to controls. Diabetic patients undergoing HD had significantly higher CIMT (P=.001) and higher levels of nitrite/nitrate (P=.05), PCO (P=.03), and GSH (P=.04) but significantly lower levels of P-SH (P<.001), serum vitamin E (P=.04), SOD (P=.02), CAT (P=.001), and GPx (P=.006) compared to diabetic patients with normal renal functions. There were significant negative correlations between CIMT and SOD (r=?0.50, P<.001), CAT (r=?0.41, P=.003), and P-SH levels (r=?0.51, P<.001) and significant positive correlation between CIMT and nitrite/nitrate levels (r=0.41, P=.003) and TBARS (r=0.35, P=.02). Linear regression analysis showed TBARS was significantly and positively correlated with CIMT (P=.04), while SOD and P-SH were significantly and negatively correlated with CIMT (P=.05 and P=.02, respectively).ConclusionsHemodialysis exacerbates oxidative stress and disturbances in antioxidant enzymes in diabetic patients. Serum nitrite/nitrate and TBARS can be used as positive determinants, while erythrocyte SOD, CAT activities, and P-SH level can be used as negative determinants of atherosclerosis assessed by CIMT in diabetic patients.  相似文献   
83.
84.
Sexually active adult Japanese quail (Coturnix coturnix japonica) were trained to run across either a left- or a right-turning runway to obtain sexual access to a conspecific of the opposite sex. The birds tested with only their right eye in use showed significantly higher latencies to complete the runway task than the birds tested binocularly and those using the left eye. In all of the three experimental conditions, male birds were significantly faster than their female counterparts. Generally, these findings are compatible with previous evidence for lateralisation in sexually motivated behaviour in birds. However, unlike the previous findings that suggested a loss of lateralisation in pattern discrimination in quail during adulthood, the present study shows that asymmetries in visually guided sexual behaviour persist in adult quail. Thus, our study implies that ontogenetic and lateralised changes within the visual system can be differently organised for different output pathways.  相似文献   
85.
OBJECTIVE: To compare effectiveness of misoprostol and ethacridine lactate with or without oxytocin in second-trimester medical abortions. SUBJECTS AND METHODS: A randomized prospective study. A total of 388 women with genetic indications for termination of pregnancy at 13-24 weeks of gestation were recruited. Group I (n=85) were treated with extra-amniotic ethacridine lactate, 10 ml instilled per gestational week, to a maximum of 200 ml. Group II (n=93) were treated with misoprostol administered intravaginally (200 microg), followed by 100 microg of oral misoprostol 4 hourly for 24 h. Group III (n=102) were treated with a combination of ethacrine lactate and oxytocin. An initial dose of 6 mU/min oxytocin was given, followed by additional 6 mU/min doses every 20 min. Group IV (n=96) were treated with a combination of misoprostol and oxytocin administered in a similar way as in group III. The main outcome measures were time to induce abortion, side effects, and failure/success rates. RESULTS: The mean time to induce abortion was 14.2+/-3.6, 13.2+/-3.4, 10.8+/-2.6, and 9.9+/-2.4 h in groups I, II, III, and IV, respectively (p<0.001). Addition of oxytocin to ethacridine lactate did not decrease the risk of prolongation of induction beyond 24 h but use of oxytocin with misoprostol did reduce the risk of induction beyond 24 h (OR: 0.46, 95%CI: 0.21-1, p<0.05). The occurrence of minor side effects was similar in all groups. CONCLUSION: Addition of oxytocin to ethacridine lactate or misoprostol significantly decreases the length of time to induce abortion without supplementary side effects.  相似文献   
86.
A case of multifocal fibrosclerosis with an extremely unusual unilateral perirenal involvement is reported. Computed tomography and magnetic resonance imaging findings of unilateral perirenal fibrosis are discussed.  相似文献   
87.
OBJECTIVE: To investigate the relationship between raloxifene administration and serum malondialdehyde (MDA), erythrocyte superoxide dismutase (SOD), erythrocyte glutathione peroxidase (GPx) levels in healthy postmenopausal women. METHODS: In a randomized and placebo-controlled design, 80 women received either 60 mg/day raloxifene or placebo for 24 weeks. MDA, SOD, and GPx levels were assessed at 0,4,12, and 24 weeks. Wilcoxon signed-rank test and Mann-Whitney U test were used for comparisons. RESULTS: Six women in the treatment arm and eight women in the placebo group discontinued the study. Mean serum MDA levels were significantly (p = 0.001) decreased from 11.4 nmol/ml at baseline to 8.9 nmol/ml at week 12 with raloxifene treatment. Mean erythrocyte SOD activity was significantly (p = 0.02) reduced from 1472 U/g Hb at baseline to 1173 U/g Hb at week 12 following raloxifene administration. Lowered serum MDA and erythrocyte SOD levels persisted during treatment. On contrary, erythrocyte GPx levels did not change significantly with raloxifene administration. CONCLUSIONS: Raloxifene (60 mg/day) lowers serum MDA levels and erythrocyte SOD activity in postmenopausal women after 12 weeks of treatment. The clinical implications of these findings need to be determined.  相似文献   
88.
The aim of this cadaver study is to define the anatomic structures on anterior sacrum, which are under the risk of injury during bicortical screw application to the S1 and S2 pedicles. Thirty formaldehyde-preserved human male cadavers were studied. Posterior midline incision was performed, and soft tissues and muscles were dissected from the posterior part of the lumbosacral region. A 6 mm pedicle screw was inserted between the superior facet of S1 and the S1 foramen. The entry point of the S2 pedicle screw was located between S1 and S2 foramina. S1 and S2 screws were placed on both right and the left sides of all cadavers. Then, all cadavers were turned into supine position. All abdominal and pelvic organs were moved away and carefully observed for any injury. The tips of the sacral screws were marked and the relations with the anatomic structures were defined. The position of the sacral screws relative to the middle and lateral sacral arteries and veins, and the sacral sympathetic trunk were measured. There was no injury to the visceral organs. In four cases, S1 screw tip was in direct contact with middle sacral artery. In two cases, S1 screw tip was in direct contact with middle sacral vein. It was observed that the S1 screw tips were in close proximity to sacral sympathetic trunk on both right and the left sides. The tip of the S2 screw was in contact with middle sacral artery on the left side only in one case. It is found that the tip of the S2 screw was closely located with the middle sacral vein in two cases. The tip of the S2 pedicle screw was in contact with the sacral sympathetic trunk in eight cases on the right side and seven cases on the left side. Lateral sacral vein was also observed to be disturbed by the S1 and S2 screws. As a conclusion, anterior cortical penetration during sacral screw insertion carries a risk of neurovascular injury. The risk of sacral sympathetic trunk and minor vascular structures together with the major neurovascular structures and viscera should be kept in mind.  相似文献   
89.
90.
OBJECTIVES: The diagnosis of premature rupture of membranes (PROM) is sometimes challenging, and common diagnostic tests are of limited value in the diagnosis. We aimed to study the accuracy of detecting insulin-like growth factor binding protein-1 (IGFBP-1) in vaginal fluid by a rapid dipstick method in comparison with the nitrazine test and amniotic fluid index (AFI) and we studied the predictivity of these methods on the latency of pregnancy in patients with suspected PROM. MATERIAL AND METHOD: One hundred and fifty-one patients (36 definite PROM, 35 no PROM and 80 suspected PROM) at 20-42 weeks' gestation were included in the study. Patients with preterm labor and PROM, patients at <20 gestational weeks, and those with multiple pregnancies were excluded. IGFBP-1 in the cervicovaginal fluid was measured by a rapid dipstick method (PROM test). AFI was measured by the four-quadrant method and an AFI of <80 mm was considered as oligohydroamnios. RESULTS: The sensitivity, specificity and accuracy of the nitrazine test, the PROM test and AFI were 97, 16 and 56%, 97, 97 and 97% and 94, 91 and 92%, respectively. The nitrazine test results were affected by vaginal discharge but the PROM test results were not affected. Only a positive PROM test was associated with delivery within 7 days [odds ratio (OR) 12; 95% confidence interval (CI) 4.2-35, p < 0.001]. CONCLUSION: The dipstick method of detecting IGFBP-1 in the vaginal fluid is a rapid, reliable and noninvasive method. The PROM test is the most accurate diagnostic test and predictor of latency in patients with suspected PROM.  相似文献   
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