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排序方式: 共有878条查询结果,搜索用时 140 毫秒
1.
Omar Abdel-Rahman 《Clinical genitourinary cancer》2019,17(2):e329-e338
Background
The objective of the study was to evaluate the outcomes of clinically localized prostate cancer treated with prostatectomy versus radiation therapy within the context of a prospective prostate cancer screening study.Patients and Methods
Within the PLCO (Prostate, Lung, Colorectal, and Ovary) trial, patients who were diagnosed with clinically localized prostate cancer and subsequently received treatment with prostatectomy or radiation therapy (with or without hormonal treatment) were included. Univariate and multivariate Cox regression analyses were then performed to determine factors affecting overall and prostate cancer-specific survival. Factors with P < .05 in univariate analysis were included in the multivariate analysis.Results
A total of 3953 patients were included in the current analysis. These included 2044 patients treated with prostatectomy and 1909 patients treated with radiation therapy with or without hormonal treatment. In an adjusted multivariate analysis for factors affecting overall survival, prostatectomy was associated with better overall survival compared with radiation therapy (hazard ratio, 0.548; 95% confidence interval [CI], 0.440- 681; P < .001). Likewise, in an adjusted multivariate analysis for factors affecting prostate cancer-specific survival, prostatectomy was associated with better prostate cancer-specific survival compared with radiation therapy (hazard ratio, 0.485; 95% CI, 0.286- 0.822; P = .007). Similar findings were found with propensity score matching and repeating the same analyses on the post-matching cohort.Conclusion
Prostatectomy seems to predict better overall and prostate cancer-specific survival compared with radiation therapy among patients with clinically localized prostate cancer diagnosed within the PLCO trial. 相似文献2.
CTLA4-Ig是一种融合免疫球蛋白,可以选择性地阻断CD28与B7的信号传导通路,导致T细胞免疫失能,诱导对特异性抗原的免疫耐受. 本文介绍了其生物学特性、免疫诱导耐受机制及在异体移植方面的研究进展和局限性,其在异体移植方面展示了良好的应用前景. 相似文献
3.
M S Abdel-Rahman G A Skowronski R M Turkall S E Gerges A H Abu-Hadeed A M Kadry 《Drug and chemical toxicology》1987,10(3-4):257-274
Alcide Allay, an antimicrobial preparation produced in gel and liquid forms, was evaluated for vaginal toxicity in guinea pigs. 1.0 g/kg Allay gel or placebo was administered intravaginally once per day over a 30 day period while 2.5 g/kg Allay liquid (containing either of two concentrations of sodium chlorite and lactic acid as active ingredients) or placebo was applied vaginally three times per day for 10 days. At the conclusion of the studies, hematology, blood and urine clinical chemistry tests and necropsies were performed. RBC, HGB, HCT, MCHC and direct bilirubin increased while CO2, SGPT and CPK decreased in blood after Allay liquid treatment. Creatinine, urea nitrogen and uric acid in urine were statistically reduced in the liquid groups. Hematology and clinical chemistry parameters were within the normal range of values reported in the literature for guinea pigs, indicating no clinical significance due to drug treatment. Significant differences in organ body/weight ratios were observed between controls and Allay gel and liquid groups. However, only the livers in the gel study and the vaginas in both studies were changed histologically. 相似文献
4.
Using adult mongrel dogs, the urodynamic characteristics of three types of ileal reservoirs were studied and compared. Segments of ileum of the same length were utilized to construct simple loop pouches (five dogs), DeKlerk pouches (five dogs) and Kock pouches (five dogs). Six to eight weeks after surgery, urodynamic evaluation was carried out. This included determination of the volume/pressure relationship and measurement of the contractions of the circular and longitudinal muscle fibers. Results indicate that the Kock pouch offers the best features in terms of the volume capacity, the volume/pressure relationship and contractile activity. Detubularization abrogated the muscle tone but it did not affect the phasic contractile activity of the circular muscle layer. 相似文献
5.
6.
新生儿和儿童乙肝免疫 总被引:3,自引:1,他引:2
陈仕珠 《世界华人消化杂志》2006,14(27):2708-2712
自1991年WHO提出将乙型肝炎病毒(HBV)疫苗纳入新生儿计划免疫以来,绝大多数国家新生儿HBV疫苗接种覆盖率平均在90%以上,婴儿HBV疫苗接种覆盖率为85%-99%.我国HBsAg携带率从10.19%下降到0.2%-3.2%.不同地区新生儿和儿童全程接种率、首针及时接种率、免疫覆盖率差异较大.对不同新生儿和儿童HB免疫尚需注意的问题如HBV疫苗接种程序和接种剂量,早产、低体质量儿的免疫接种,HBsAg阳性母亲子女的免疫接种和母乳喂养,抗-HBs保护时间和加强免疫问题. 相似文献
7.
Human papillomavirus infection in Egyptian esophageal carcinoma: correlation with p53, p21, mdm2, C-erbB2 and impact on survival 总被引:1,自引:0,他引:1
The etiological role of human papillomavirus (HPV) in esophageal carcinoma (EC) in relation to p53, mdm2, p21(waf), c-erbB2 and the overall survival (OS) rate was investigated. Tumor and normal tissues from 50 EC were evaluated by polymerase chain reaction and InnoLiPA for HPV. Single strand conformation polymorphism/sequencing were used to detect p53 gene mutations. Immunohistochemistry was performed to determine p53, mdm2, p21(waf)and c-erbB2 expression. Human papillomavirus was detected in 54% of tumors and in 24% of normal tissues. p53, mdm2 and c-erbB2 overexpression was detected in 68%, 70% and 60% of tumors and in 14%, 16% and 10% of normal samples, whereas loss of p21(waf) was evident in 64% of tumors. p53 mutations were detected in 20% of cases. Exon 8 and 5 showed the highest mutation rate (40% each), followed by exons 6 and 7 (10% each). There was a significant correlation between HPV and p53, mdm2, c-erbB2 overexpression. The OS was significantly associated with overexpression of p53 and loss of p21(waf). Human papillomavirus infection is frequent in Egyptian EC. Both p53-dependent and p53-independent pathways seem to be involved in HPV-associated EC. mdm2 and c-erbB2 are possible targets for HPV in the p53-independent pathway. However, only advanced stage and aberrant expression of p53 and p21(waf) are independent prognostic markers. 相似文献
8.
Summary The venous architecture in donor flaps was observed in 17 fresh cadavers by injection of latex or ink into the vessels or by making corrosion-cast specimens. The pattern of the veins resembles that of the arteries, with the difference that there is another set of venous trunks which do not accompany the arteries. Because these trunks are of larger caliber, they are the main drainage route for flaps. There are three types of drainage based on the anatomical architecture: 1) the superficial trunk is the main drainage path; 2) the deep trunk is the main path; 3) both superficial and deep veins are involved. These morphological considerations are the basis for selection of veins for anastomosis in microsurgery. The axial veins in temporal, frontal and facial flaps on the dorsum of the hand and the foot usually loosely accompany the axial arteries. The characteristics of these vascular pedicules should be studied in transplant operation.
Bases anatomiques du drainage veineux des lambeaux cutanés libres
Résumé Le drainage veineux des lambeaux cutanés libres a été étudié sur 17 cadavres frais par injection de latex ou d'encre dans les vaisseaux, ou en réalisant des moulages par injection-corrosion. La distribution des veines ressemble à celle des artères à la différence près qu'il existe des troncs veineux qui n'accompagnent pas les artères. Ces troncs ont un calibre plus important et représentent une voie de drainage principale pour les lambeaux. On peut individualiser trois types de drainages basés sur l'architecture veineuse : 1. Le tronc superficiel est la principale voie de drainage ; 2. le tronc profond est la principale voie; 3. les veines superficielles et profondes sont impliquées simultanément. Ces considérations morphologiques sont les bases de la sélection des axes veineux pour les anastomoses en micro-chirurgie. Les veines axiales au niveau temporal, frontal et facial et pour les lambeaux de la face dorsale de la main et du pied sont habituellement relativement éloignées du trajet artériel. Les caractéristiques de ces pédicules veineux doivent être précisées pour la réalisation des lambeaux.相似文献
9.
Susan M Abdel-Rahman Nasreen Talib Ada Solidar Amy Jo Nopper Gerald J Wyckoff 《Medical mycology》2008,46(3):217-223
Trichophyton tonsurans infections occur in various host populations, on various body sites and with varying degrees of inflammation. This investigation was undertaken to determine whether fungal factors could explain the degree of severity in clinical symptomatology among infected children. Otherwise healthy children (n=54) presenting with tinea capitis were enrolled in this study. A thorough history was performed, the extent and severity of infection graded and a fungal specimen collected from each child. Strain type was determined by genotyping for 11 sequence variations in the rDNA and ALP1 loci. Secreted protease activity was quantitated after 5 days of growth in aqueous medium. Forty participants were evaluable. Infection duration ranged from 1 day to 3 years and clinical severity score (CSS) from 4-19. Seventeen unique fungal genotypes were present. Keratinase, collagenase and elastase activity varied 32.7-fold, 64.9-fold and 303.3-fold, respectively. A significant association was observed between genotype and disease severity with the rDNA sequence variations accounting for over 50% of the variation observed in CSS (r2=0.539; P<0.001). Phylogenetic analyses appear to suggest that the ancestral strain types of T. tonsurans cause more severe disease. These observations are consistent with reports that recently diverge anthropophilies are associated with diminished inflammatory involvement. 相似文献
10.
Our previous studies showed that ethanol selectively counteracts centrally mediated hypotensive responses. In this study, we investigated the role of sympathetic nerve activity, cardiac output (CO), and total peripheral resistance (TPR) in this antagonistic hemodynamic interaction between ethanol and clonidine. Changes in blood pressure (BP), heart rate (HR), CO, stroke volume (SV), and TPR elicited by intracisternal (i.c.) clonidine and subsequent ethanol or saline were evaluated in conscious freely moving spontaneously hypertensive rats (SHRs). Clonidine (0.5 microg, i.c.) evoked hypotension was due to a significant reduction in TPR (from 3.6+/-0.21 to 2.8+/-0.17 mm Hg/ml/min/100 g), which was associated with a significant (p < 0.05) reduction in plasma norepinephrine (NE, from 660+/-115 to 310+/-50 pg/ml), measured as index of sympathetic activity. Ethanol (1 g/kg, i.v.) counteracted the hypotensive effect of clonidine and produced significant (p < 0.05) increases in plasma NE and TPR. Further support for the hypothesis that ethanol selectively counteracts centrally mediated hypotension was sought by investigating the effect of ethanol on peripherally mediated hemodynamic responses to hydralazine. Hydralazine (0.4 mg/kg, i.v.) produced a hypotension similar in magnitude to that produced by clonidine, which was also due to a significant reduction in TPR. However, unlike the case with clonidine, reflex increases in HR, SV, and hence CO were evident. Ethanol given after hydralazine produced a short-lived pressor effect (<10 min vs. 60 min in case of clonidine) in spite of a sustained increase in TPR. The latter was offset by the simultaneous decreases in CO, SV, and HR. A 30% increase in plasma NE caused by hydralazine returned to baseline level after ethanol or saline. Blood ethanol concentrations were similar in all treatment groups. These findings suggest that ethanol selectively counteracts centrally evoked hypotensive responses by counteracting the sympathoinhibition-mediated decreases in TPR elicited by centrally administered clonidine in conscious SHRs. 相似文献