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991.
992.
Angel Josabad Alonso-Castro Candy Carranza-álvarez Ma Catalina Alfaro-De la Torre Leonardo Chávez-Guerrero Ramón Fernando García-De la Cruz 《Archives of environmental contamination and toxicology》2009,57(4):688-696
We investigated the effect of Cd and Pb on the growth of the aquatic macrophyte Typha latifolia; the removal from the solution and the accumulation of these elements by the plant were also studied. Thus, small plants
of T. latifolia, collected from a noncontaminated site, were exposed for 10 days to Cd and Pb, in a single solution or in mixture solutions,
at two concentrations of the metals (5 and 7.5 mg/L). Our results showed that T. latifolia removed effectively Cd and Pb from solutions and was able to accumulate these metals in the roots and, to a lesser extent,
in the leaves. Our findings suggested a synergistic effect of Cd and Pb with respect to the toxicity to T. latifolia. Additionally, Cd diminished the Pb absorption by T. latifolia. Our results confirmed, using scanning electron microscopy, the internalization of Cd and Pb in T. latifolia. 相似文献
993.
A total of 6,493 fractures was studied from 6,389 children younger than 16 years admitted as inpatients to one center in a 10-year period. The boy-to-girl ratio increased from 1.4:1 in the infants to 4.9:1 in the adolescents. The most common fractures were the distal radius (20.2%), supracondylar fracture of the humerus (17.9%), forearm shaft (14.9%), and the tibial shaft (11.9%). A distinct age-specific fracture pattern also was found, with supracondylar fracture of the humerus being the most common fracture in the age 0- to 3-year (26.7%) and the 4- to 7-year (31.6%) groups and distal radius in the 8- to 11-year and the 12- to 16-year groups (24.3 and 25.7%, respectively). Although the overall pattern of the major fractures had not changed over the 10-year period, significant changes in the treatment pattern were observed. The closed-reduction and percutaneous pinning rates increased from 9.5 to 38.7% in fracture of the distal radius, 4.3 to 40% in the supracondylar humerus, and 1.8 to 22% in the forearm shaft. The changes in treatment pattern were also accompanied by a corresponding decrease in the open-reduction rate and hospital stay periods from <10% to 38% of patients being discharged within 1 day of admission in the 10-year period. 相似文献
994.
995.
996.
The clinicopathological significance of p21 and p53 expression in esophageal squamous cell carcinoma: an analysis of 153 patients 总被引:5,自引:0,他引:5
King Y. Lam M.B.B.S. F.R.C.P.A. Simon Law M.B.B.Chir F.R.C.S.Ed. Lo Tin M.Med.Sci. Peter H.M. Tung M.B.B.S. F.R.C.S.Ed. John Wong Ph.D. F.R.A.C.S. F.R.C.S.Ed. 《The American journal of gastroenterology》1999,94(8):2060-2068
OBJECTIVE: The p21 gene is thought to play a central role in tumor suppression. The aim of this study was to examine the clinicopathological role of p21 and p53 in esophageal squamous cell carcinomas. METHODS: The expression of p21 and p53 proteins in 153 Chinese patients (131 men, 22 women) with resected esophageal squamous cell carcinomas was investigated by the immunohistochemical method. Correlation between p21 and p53 expression and clinicopathological features was examined. RESULTS: The expression of p21 and p53 was detected in 70% and 64% of the tumors, respectively. The staining of p21 and p53 was also found in squamous carcinoma in situ, dysplasia, and nontumor epithelium. p21 expression was often weak in the suprabasal cells and found in better differentiated tumors. There was no significant correlation between the expression of p21 and the abnormal accumulation of p53. The prognosis of the patients depended on the size, stage, and p21 expression of the lesion. In stage III lesions with tumor diameter < or = 7.5 cm (n = 93), patients with loss of p21 expression had better survival. The survival rates of patients were worse if they had expression of both p21 and p53. CONCLUSIONS: Thus, p21 and p53 had prognostic value for esophageal squamous cell carcinomas. Loss of p21 expression was shown without p53 alternations, indicating that other mechanisms are also involved in turning off the gene. The pattern of p21 and p53 expression predicts an aggressive clinical course of esophageal squamous cell carcinomas. 相似文献
997.
Presbytis cristata monkeys infected through the inoculation of between 200 and 400 subperiodicBrugia malayi infective larvae (L3) in the right thight, in both thighs or in the dorsum of the right foot were followed up for varying periods of up to about 8 months after infection. All 148 inoculated animals became patient, with mean prepatent periods being between 66 and 76 days. In animals injected in the thigh, the patterns of microfilaraemia were similar, there being a rapid rise in the geometric mean counts (GMCs) of microfilariae during the first 10–12 weeks of patency, which then plateaued at levels of >1000/ml. Adult worm recovery, expressed as the percentage of the infective dose, was significantly higher in animals injected with 100 L3 in each thigh, being 9.4% as compared with 2.8%–4.8% in other groups. It is therefore recommended that animals should be injected with 100 L3 in each thigh and that the testing of potential filaricides in this model be carried out during the phase of rapid increase in microfilaraemia to ensure that any microfilaricidal effect can easily be detected. 相似文献
998.
999.
Tam-Lin Chow FRCS FHKAM Tony Tung-Fei Chan FRCS FHKAM Chi-Yee Choi FRCS FHKAM Siu-Ho Lam FRCS FHKAM 《Otolaryngology--head and neck surgery》2008,138(6):752-755
OBJECTIVE: To assess the feasibility and advantages of submandibular sialoadenectomy under local anesthesia. STUDY DESIGN: Retrospective clinical study. SUBJECTS AND METHODS: Twenty patients with benign submandibular masses underwent submandibular sialoadenectomy. The procedure was carried out under local anesthesia (LA) in 12 patients and general anesthesia (GA) in 8 patients. The patient and tumor characteristics, as well as treatment outcome or complications, were compared between the two groups. RESULTS: There was no conversion from LA to GA. Nine patients in the LA group could be discharged as day-case surgery versus none in the GA group, P = 0.001. The postoperative hospital stay was also much shorter in the LA group: 0.4 day vs 2.0 days, P < 0.001. Postoperative vomiting occurred in only two of the eight patients of the GA group. Complication rate was similar. CONCLUSION: Submandibular sialoadenectomy under local anesthesia is feasible. It can shorten the hospital stay and facilitate day-case surgery. 相似文献
1000.
Ho‐Yin Ngai Lap‐Yin Ho Tung‐Fei Chan Hing‐Shing So Venu Velayudhan Siu‐Ho Lam 《Surgical Practice》2008,12(3):99-101
Renal cell carcinoma (RCC) may present as metastatic disease. However, RCC with solitary sternal metastasis is rare. We report a rare case of RCC with synchronous solitary sternal metastasis. The patient underwent radical nephrectomy, sternal tumour resection and reconstruction as a one‐stage procedure. The role of open sternal biopsy is also described. Review of the literature was carried out and a reasonably lengthy survival was observed. We concluded that radical surgical resection and reconstruction may offer the best chance of survival in managing RCC with solitary sternal metastasis in renal cell carcinoma. 相似文献