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51.
This study investigated the protective effects of melatonin against formaldehyde-induced oxidative damage and apoptosis in rat testes. A total of 21 male Wistar rats were divided into three groups. Group I was used as a control, Group II was injected every other day with formaldehyde for 1 month, whereas Group III was injected every other day with formaldehyde and melatonin for 1 month. At the end of the experimental period animals were sacrificed and the testes removed and dissected from the surrounding tissues for immunohistochemical evaluation. In addition, the levels of superoxide dismutase (SOD), glutathione peroxidase (GSH-Px), and malondialdehyde (MDA) were determined. The levels of SOD and GSH-Px decreased significantly, whereas the level of MDA significantly increased in animals treated with formaldehyde compared with the controls. Apoptosis of spermatogenetic and Leydig cells of testicular tissues was observed. In contrast, rats with melatonin SOD and GSH-Px enzyme activity increased whereas MDA levels decreased with formaldehyde exposure along with apoptosis. In view of the present findings, it is suggested that melatonin treatment may prevent formaldehyde-induced oxidative damage and apoptosis in rat testes.  相似文献   
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Objective

There have been conflicting data about the role of increased levels of homocysteine (Hcy) on haemostatic system. We aim to investigate prospectively the relation between serum Hcy levels and changes in haemostatic system in pregnancy and postpartum period.

Study design

Sixty-eight healthy pregnant women were included in the study. Blood samples were obtained in the 11th gestational week, 25th gestational week, 32nd gestational week and postpartum 4th week. The haemoglobin levels, white blood cell count (WBC), platelet count, activated partial thromboplastin time (aPTT), prothrombin time (PT), fibrinogen, D-dimer, Hcy, vitamin B12, and folate levels were measured.

Results

Serum Hcy levels were negatively correlated with D-dimer levels (r = −0.57, p < 0.0001). The highest levels of D-dimer (1046.62 ± 322.01 ng/ml) were achieved in the third trimester and the lowest levels of serum Hcy (4.45 ± 1.23 mmol/l) were detected in the same trimester. In postpartum fourth week, D-dimer levels were decreased to normal levels (238.27 ± 198.59 ng/ml) while the serum Hcy levels were reached to the highest levels (7.99 ± 1.36 mmol/l).

Conclusion

The negative correlation between Hcy and D-dimer levels may be a compensatory mechanism to maintain the normal haemostatic balance in pregnancy. Hence, possible advantage of low Hcy levels in pregnancy may be to prevent undesired thrombosis.  相似文献   
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The aim of this study was to evaluate the presence of transferred measles antibodies and seronegativity rates during early infancy in premature newborns whose mothers had infection-induced immunity. The premature group was composed of 22 and 35 newborns of gestational ages < 32 wk and > 32 wk, respectively, and the control group consisted of 28 term newborns. Enzyme-linked immunosorbent assay (ELISA) was used for the qualitative detection of IgG antibodies to measles virus. Mean cord blood relative values were significantly lower in both premature groups, < or = 32 wk (p < 0.0001) and > 32 wk (p < 0.001), when compared with term infants. No seronegative infant was found in the premature group at 2 mo of age. At 4 mo, the seronegativity rate was 27% for premature infants < or = 32 wk and 35% for those > 32 wk. At 6 mo, seronegativity increased to 86% and 74% for premature infants born at gestational ages < or = 32 wk and > 32 wk, respectively. Forty-six percent of the term infants became seronegative at that age. The differences between term infants and those in the two premature groups were statistically significant (p < 0.05 and p < 0.005). Premature infants, regardless of their prematurity degree, were thought to be more susceptible to measles infection than term ones at the age of 6 mo. Policies for their protection from measles infection are still to be investigated.  相似文献   
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PURPOSE: To present our experience with ureteroscopy and holmium laser lithotripsy in pregnant patients and discuss the need for stents postoperatively. PATIENTS AND METHODS: A retrospective analysis was performed on seven consecutive pregnant patients presenting with renal colic necessitating intervention between 1997 and 2003. One patient presented during the first, five in the second, and one in the third trimester. Abdominal ultrasonography was the primary diagnostic test. If the stone could not be seen with a rigid ureteroscope, flexible ureteroscopy (f-URS) was performed. Stones were fragmented with a holmium laser, and large fragments were taken out. Ureteral stents were placed routinely in all but the first two patients. RESULTS: The ureteral stones could be seen with ultrasonography in three patients. In four patients, holmium lasertripsy could be done by the rigid ureteroscope. In the remaining patients, f-URS was performed, and two upper-system stones were fragmented. Six patients were rendered stone free. In one patient, both collectingsystem dilation and right perirenal liquid accumulation were present by ultrasonography, but no stones could be detected. Ureteral-stent insertion reduced postoperative pain and analgesic use in the whole group. CONCLUSIONS: When conservative therapy fails in the pregnant patient with a ureteral stone, ureteroscopy and holmium lasertripsy should be considered. Routine insertion of ureteral stents with pull-out strings for at least 72 hours will reduce the pain and analgesic use postoperatively.  相似文献   
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BACKGROUND: We evaluated 70 cases of ocular injuries with intraocular foreign bodies to determine the results of surgical management. METHODS: The site of penetration was cornea in 58 (82.9%), sclera in 8 (11.4%), and limbus in 4 (5.7%) eyes. The foreign body was in the vitreous in 40 (57.1%) and embedded in the retina in 30 (42.9%) cases. Before pars plana vitrectomy, the most common findings were found to be lens perforation (77.1%), vitreous hemorrhage (45.7%), endophthalmitis (20%), hyphema (4.3%), and retinal detachment (2.9%). RESULTS: After pars plana vitrectomy, visual acuity improved in 39 (55.7%), did not change in 19 (27.2%), and decreased in 8 (11.4%) cases. We observed secondary glaucoma in 11 (15.7%), retinal detachment in 10 (14.3%), and phthisis bulbi in 3 (4.3%) cases postoperatively. CONCLUSION: Pars plana vitrectomy is found to be an effective therapeutic approach in removing intraocular foreign bodies, but the preoperative and postoperative complications determine the visual outcome.  相似文献   
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Aim: To show the oxidative stress after cigarette smoke exposure in rat testis and to evaluate the effects of caffeic acid phenethyl ester (CAPE). Methods: Twenty-one rats were divided into three groups of seven. Animals in Group Ⅰ were used as control. Rats in Group Ⅱ were exposed to cigarette smoke only (4 × 30 min/d) and rats in Group Ⅲ were exposed to cigarette smoke and received daily intraperitoneal injections of CAPE (10 μmol/kg.d). After 60 days all the rats were killed and the levels of nitric oxide (NO) and anti-oxidant enzymes such as superoxide-dismutase, catalase and glutathione peroxidase (GSH-Px) and the level of malondialdehyde were studied in the testicular tissues of rats with spectrophotometric analysis. Results: There was a significant increase in catalase and superoxide-dismutase activities in Group Ⅱ when compared to the controls, but the levels of both decreased after CAPE administration in Group Ⅲ. GSH-Px activity was decreased in Group Ⅱ but CAPE caused an elevation in GSH-Px activity in Group Ⅲ. The difference between the levels of GSH-Px in Group Ⅰ and Group Ⅱ was significant, but the difference between groups Ⅱ and Ⅲ was not significant. Elevation of malondialdehyde after smoke exposure was significant and CAPE caused a decrease to a level which was not statistically different to the control group. A significantly increased level of NO after exposure to smoke was reversed by CAPE administration and the difference between NO levels in groups Ⅰ and Ⅲ was statistically insignificant. Conclusion: Exposure to cigarette smoke causes changes in the oxidative enzyme levels in rat testis, but CAPE can reverse these harmful effects. (Asian J Andro12006 Mar; 8: 189-193)  相似文献   
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