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1.
Background: Hepatitis B (HB) vaccine represents one of the major achievements in the 20th century. The most important epidemiologic factor affecting the chronic carrier rate is age of infection. The earlier in life an infection occurs, the higher the probability that this infection will result in chronic carriage. Methods: A seroepidemiologic study was conducted to examine the impact of HB vaccination on the carrier state among a vaccinated group of children (1000) compared to a non-vaccinated group (500) aged 6 years in Alexandria, Egypt. Results: The rate of HbsAg positivity among the vaccinated group was found to be 0.8% compared to 2.2% among the non-vaccinated group. The study showed that the efficacy of HB vaccine in preventing the carriage of HbsAg, 5 years after full course vaccination, was estimated to be around 67%. However, long-term monitoring should continue to confirm the efficacy of the vaccine in preventing chronic carrier state. On the other hand, studying the exposure to some risk factors associated with hepatitis B virus (HBV) infection revealed more or less a similar pattern of exposure among both vaccinated and unvaccinated children. Conclusion: It can be concluded that the significantly lower rate of HbsAg positivity among the vaccinated compared to the rate among the non-vaccinated is attributed to the preventive effect of the vaccine.  相似文献   
2.
The present study was designed to evaluate the effect of combining fractional CO2 laser with narrow-band ultraviolet B (NB-UVB) versus NB-UVB in the treatment of non-segmental vitiligo. The study included 20 patients with non-segmental stable vitiligo. They were divided into two groups. Group I received a single session of fractional CO2 laser therapy on the right side of the body followed by NB-UVB phototherapy twice per week for 8 weeks. Group II received a second session of fractional CO2 laser therapy after 4 weeks from starting treatment with NB-UVB. The vitiligo lesions were assessed before treatment and after 8 weeks of treatment by VASI. At the end of the study period, the vitiligo area score index (VASI) in group I decreased insignificantly on both the right (?2.6%) and left (?16.4%) sides. In group II, VASI increased insignificantly on the right (+14.4%) and left (+2.5%) sides. Using Adobe Photoshop CS6 extended program to measure the area of vitiligo lesions, group I showed a decrease of ?1.02 and ?6.12% in the mean area percentage change of vitiligo lesions on the right and left sides, respectively. In group II the change was +9.84 and +9.13% on the right and left sides, respectively. In conclusion, combining fractional CO2 laser with NB-UVB for the treatment of non-segmental vitiligo did not show any significant advantage over treatment with NB-UVB alone. Further study of this combination for longer durations in the treatment of vitiligo is recommended.  相似文献   
3.
Patients with sickle cell disease experience hemolytic anemia and vaso-occlusions that result in pain, organ injury, and premature mortality. Several prospective studies have verified the efficacy and tolerability of hydroxyurea (HU), and demonstrated its efficacy in reducing painful vaso-occlusive crises (VOCs) in addition to its ability to increase Hb F levels. We aimed to evaluate the long-term effects of HU therapy on Hb F and assess its long term efficacy and safety in sickle cell disease patients. A retrospective study on 60 sickle cell disease patients was conducted. We studied the laboratory changes, frequency of VOCs per year, frequency of hospital admisions per year and number of transfusions per year, both before and after HU therapy. The follow-up period was 4 to 120 months. Hb F levels after HU therapy positively correlated with the duration of HU therapy, baseline Hb F levels and baseline total hemoglobin (Hb) (r?=?0.4, p?=?0.04; r?=?0.45, p?=?0.001; r?=?0.5, p?=?0.019, respectively) and inversely correlated with baseline total leucocyte count (r?=?–0.33, p?=?0.034). Hydroxyurea therapy was associated with an increase in the total Hb and mean corpuscular volume (MCV) (p?=?0.009, p?=?0.000; respectively) and with a decrease in total leucocyte count, platelet count and reticulocyte count (p?=?0.00, p?=?0.03, p?=?0.02, respectively). Moreover, a significant reduction in the frequency of VOCs, transfusion frequency and hospital admissions per year after HU therapy was shown in the studied subjects. Hydroxyurea induced an increase in Hb F level, which was maintained over time and was associated with clinical efficacy and acceptable safety.  相似文献   
4.
AIM: To investigate low intensity laser irradiation phototherapy (LILIP) on the proliferation, mineralization and degradation of dental pulp constructs. METHODS: Stem cells from human exfoliated deciduous teeth (SHED) were grown to confluence and seeded on collagen scaffolds to create dental pulp constructs. LILIP was delivered to the dental pulp constructs using an 830 nm GaAIAs laser at an output power of 20 mW. The LILIP energy density was 0.4, 0.8, 1.2, and 2.4 J/cm2. After 8 d, the cell proliferation and degradation within the dental pulp constructs were measured using histologic criteria. After 28 d, the effect of LILIP on SHED mineralization was assessed by von Kossa staining. RESULTS: SHED proliferation within the dental pulp constructs varied after exposure to the 0.4, 0.8, 1.2, and 2.4 J/cm2 LILIP energy densities (P < 0.05). The maximum proliferation of SHED in nutrient deficient media was 218% after exposure to a 1.2 J/cm2 LILIP energy density. SHED grown in nutrient deficient media after exposure to a 0.4, 0.8, and 1.2 J/cm2 LILIP energy density, proliferated by 167-218% compared to the untreated (non-LILIP) control group (P < 0.05). SHED exposed to a 0.4, 0.8, and 1.2 J/cm2 LILIP energy density, and grown in optimal nutritional conditions and proliferated by 147%-164% compared to the untreated (non-LILIP) control group (P < 0.05). The exposure of SHED to the highest LILIP energy density (2.4 J/cm2) caused a reduction of the cell proliferation of up to 73% of the untreated (non-LILIP) control (P < 0.05). The amount of mineral produced by SHED increased over time up to 28 d (P < 0.05). The 0.8 and 1.2 J/cm2 LILIP energy densities were the most effective at stimulating the increased the mineralization of the SHED from 150%-700% compared to untreated (non-LILIP) control over 28 d (P < 0.05). The degradation of dental pulp constructs was affected by LILIP (P < 0.05). The dental pulp constructs grown in optimal nutritional conditions exposed to a 0.8 J/cm2 or 1.2 J/cm2 LILIP energy density had 13% to 16% more degradation than the untreated (non-LILIP) control groups (P < 0.05). The other LILIP energy densities caused a 1% degradation of dental pulp constructs in optimal nutritional conditions (P > 0.05). CONCLUSION: LILIP can enhance or reduce SHED proliferation, degradation and mineralization within dental pulp constructs. LILIP could promote the healing and regeneration of dental tissues.  相似文献   
5.
BACKGROUND AND OBJECTIVES: In cases of beta-thalassemia major, apoptosis appears to be greatly enhanced in the early-stage erythroid precursors in the bone marrow leading to ineffective erythropoiesis. L-Carnitine is found to strongly reduce apoptosis in different diseases. We investigated the effect of oral L-carnitine therapy on apoptosis in thalassemia major patients. METHODS: Eighteen thalassemia major patients with a mean age of 12.2 +/- 6.6 years were included. Detection of apoptosis was done by photometric enzyme immunoassay (ELISA) and agarose gel electrophoresis before and after 6 months of oral therapy with L-carnitine (50 mg/kg/day). RESULTS: A significant decrease of apoptosis frequency in the erythroid precursors in the bone marrow of studied cases was noted after therapy. The quantity of nucleosomes measured by ELISA dropped from 3.65 +/- 1.338 to 1.60 +/- 0.65 after therapy (p = 0.005). A positive ladder pattern reflecting apoptosis on agarose gel electrophoresis was detected in 88.9% of cases prior to treatment versus 16.7% after therapy (p = 0.006). Patients also had a significant decrease in the frequency of transfusions and increase in the pre-transfusion hemoglobin levels after therapy. CONCLUSION: L-Carnitine seems to be a good modulator of apoptotic processes in thalassemic patients leading to a decreased frequency of programmed erythroblast death and general improvement of the disease condition.  相似文献   
6.
Patients with thalassemia major requiring regular blood transfusions accumulate iron that is toxic to the heart, liver, and endocrine systems. The following prospective, randomized trial was carried out to determine the effectiveness, in children and young adults, of combined deferiprone (DFP) and deferoxamine (DFO) in reducing transfusional iron overload compared to either drug alone and to assess the safety and tolerability of DFP. Sixty-six patients were randomized into three treatment arms: daily DFP combined with DFO twice weekly; daily DFP only; and DFO only 5 days/week. Fifty-six patients completed the 54 weeks and were assessed by different indices. A significant reduction of liver iron concentration and serum ferritin was observed in all three arms while significant reduction of liver iron score was observed in patients on combination therapy only. Cardiac function did not significantly change in any arm. Compliance improved in patients who received combined therapy. Toxicity of DFP was mild to moderate and acceptable; most commonly, transient arthropathy and nausea/vomiting were observed. Thus, combination therapy has shown to be effective in reducing iron overload in thalassemia patients.  相似文献   
7.
Cardiac complications, such as pulmonary hypertension (PHT), are the leading cause of death in β-thalassemia patients. L-Carnitine, due to its role in fatty acid oxidation, might help control the elevation in pulmonary artery systolic pressure (PASP). The objectives of this study were to assess the prevalence of PHT in β-thalassemia major patients, identify clinical predictors for its development, and determine the potential effects of L-carnitine. In total, 32 patients with β-thalassemia major were recruited; 16 age- and sex-matched children constituted the control group. Cardiac evaluation was performed by using echocardiography. The patients with PHT received 50 mg/kg/day L-carnitine orally for 3 months and were then reevaluated. Based on PASP, the patients were divided into group A without PHT and group B with PHT. The prevalence of PHT was 37.5%. The other echocardiographic measurements were not significantly different between groups A and B. PASP did not have any significant correlation with the following variables: age, total number of blood units received, splenic status, serum ferritin level, and ejection fraction. Following the administration of L-carnitine, there was a significant decrease in the mean PASP from 33.96 ± 7.85 to 24.11 ± 7.61. All cardiac dimensions decreased following L-carnitine, but the changes were not statistically significant. Even though β-thalassemia major resulted in an elevation in the PASP in only a fraction of the patients, it seems to have an impact on the heart dimensions and function of all patients. No clinical predictors were identified. Oral administration of L-carnitine appears to significantly improve PASP.  相似文献   
8.
Background and aim of work: Sickle cell disease (SCD) is an inherited disease of the beta globin gene. The βS globin gene haplotypes are Senegal, Benin, Bantu, Cameroon, Arab-Indian and atypical haplotypes. In SCD, stroke is a life-threatening event in both adults and children. In light of paucity of studies on βS globin gene haplotypes in Egypt, we aimed to determine βS globin gene haplotypes in children with SCD and study their impact on stroke risk.

Methods: Fifty-two SCD patients were included in the study, they were 26 males and 26 females with age range from 3 to 18 years old. The PCR-RFLP technique was used for the determination of βS globin gene haplotypes. Transcranial Doppler (TCD) was done to identify patients at risk of stroke.

Results: Benin/Benin was the most prevalent haplotype detected in 50% followed by Benin/Bantu in 30.8% of studied patients. TCD study showed that 14/52 (26.9%) patients had abnormally high TCD flow velocities (TCD velocities ≥170?cm/s) and thus considered high stroke risk group, whereas 38/52 (73.1%) patients had TCD flow velocities <170?cm/s and are considered low stroke risk group. Stroke risk was not found to be associated with βS globin gene haplotype (p?=?.532).

Conclusion: This study provides a relevant contribution to our understanding of the anthropological and historical background of the population in Egypt where Benin haplotype is the commonest βS globin gene haplotype and homozygous Benin/Benin is associated with higher stroke risk than other haplotypes.  相似文献   
9.
The reaction of acetoacetanilide (1) with the α-cyanocinnamonitrile derivatives2 yielded the Michael adducts4 which could be converted into the pyrano[2,3-c] pyrazole derivatives5 via their reaction with hydrazine hydrate. Cyclisation of4 afforded the cyanoaminopyrans9 which could in turn be converted into the corresponding pyridine derivatives10. The pyranopyrazoles9 reacted with different activated nitrile derivatives (3a-c) to give the pyrano[2,3-c]pyridine derivatives13, 16 and19 respectively. The biological activity of the synthesised heterocyclic derivatives was investigated and discussed.  相似文献   
10.
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