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31.
Synchronous carcinoma in the head and neck, lung, or esophagus may be identified in 10 percent of patients with squamous head and neck carcinoma by routinely performing triple endoscopy (direct laryngoscopy, bronchoscopy, and esophagoscopy) at the time of initial evaluation. In 5.5 percent of patients with squamous head and neck cancer, synchronous lung and/or esophageal cancer was identified. However, in only 1.5 percent of patients was it asymptomatic and would not have been suspected as a result of a thorough history, physical examination, and chest x-ray.The cost-effectiveness of routine triple endoscopy can be questioned, but we think it is indicated to identify those early carcinomas with an excellent chance of cure. The time and money expended to identify these early, asymptomatic cancers is small compared to that spent in treating patients with symptomatic cancer of the same organs, in whom there appears to be a much smaller chance of cure.Multiple superficial squamous carcinomas of head and neck mucosa may be managed by surgical excision, radiation therapy, laser destruction, or cryosurgery. If these methods cannot be applied, combination chemotherapy appears to provide a satisfactory alternative method of short-term control, which we believe merits further clinical investigation.  相似文献   
32.
Previous studies have shown that diabetes mellitus leads in rats to a 45% decrease in cardiac Ca++ activated myosin ATPase, a change in myosin isoenzyme distribution and a lowering of plasma T4 and T3 levels. Hypothyroidism causes similar changes in myosin ATPase and myosin isoenzyme distribution. We determined if thyroid hormone administration in physiological replacement dose (0.3 microgram T3/100 g BW) or pharmacological doses (3 micrograms T3/100 g BW and 10 micrograms T4/100 g BW) can normalize myosin ATPase and isoenzyme distribution in diabetic rats. Control animals have a Ca++ myosin ATPase activity of 1.23 +/- 0.14 mumol Pi/mg protein/min and myosin V1 represented 70% and myosin V3 15% of total myosin. Four weeks after streptozotocin administration myosin ATPase was 0.61 +/- 0.14, and myosin V3 represented 67% of total myosin. Administration of 0.3 microgram T3/100 g BW/day for four weeks to diabetic animals resulted in no significant increase in myosin ATPase (0.69 +/- 0.07 mumol Pi/mg protein/min) or in myosin isoenzyme distribution. In contrast, administration of 3 micrograms T3/100 g BW/day or 10 micrograms T4/100 g BW/day for 4 wk led to a normalization of myosin ATPase activity (for T3 1.03 +/- 0.18, for T4 1.06 +/- 0.15). In addition the myosin isoenzyme distribution pattern normalized. These findings may point to a diminished thyroid hormone responsiveness in diabetic rats or could result from diabetes related disturbances of cellular metabolism, which are normalized by pharmacologic doses of thyroid hormone.  相似文献   
33.
A review of 30 children who had perforations of the bowel or gallbladder during a typhoid fever epidemic in Mexico City indicates that an excellent prognosis can be expected in children.The early diagnosis and aggressive management of hypovolemia is perhaps the most important factor. Bowel perforations were treated by a simple suture closure or resection in appropriate cases. There were innumerable postoperative complications, the most common being intraperitoneal abscess.In spite of the seriousness of the illness of these children and the frequency of postperforation complications, there was no operative mortality. The overall mortality was 3%.  相似文献   
34.
Yang Y  Zhou Z  He S  Fan T  Jin Y  Zhu X  Chen C  Zhang ZR  Huang Y 《Biomaterials》2012,33(7):2260-2271
Galectin-3 (Gal-3), over-expressed on a variety of human tumor cells, is a potential binding site for targeted metastatic prostate cancer therapy. The aim of this study was to develop a G3-C12-mediated drug delivery system based on N-(2-hydroxypropyl) methacrylamide (HPMA) copolymers targeting to Gal-3-expressed human PC-3 prostate carcinoma cells. 5-Fluorouracil (5-Fu), an anti-tumor agent, was selected as a model drug. G3-C12, a binding peptide, which specifically binds to the carbohydrate-recognition domain (CRD) of Gal-3, was attached to HPMA copolymers as a targeting moiety. Compared with non-targeted conjugates (P-Fu), Gal-3-targeted HPMA copolymer-(G3-C12)-5-Fu conjugates (P-(G3-C12)-Fu) displayed a superior intracellular internalization followed by enhanced cytotoxicity and apoptosis-induction. Subsequently, the in vitro migration study on PC-3 cells indicated that P-(G3-C12)-Fu was able to efficiently inhibit the cell migration ability after wounding. On PC-3 tumor-bearing mice model, G3-C12-modified copolymers showed a higher tumor accumulation coupled with a faster clearance from blood circulation than non-modified ones. Finally, Gal-3-targeted conjugates significantly improved the anti-tumor activity of 5-Fu in nude mice bearing PC-3 tumor xenografts. Consequently, G3-C12 would be a promising targeting moiety for cell-specific prostate cancer therapy in future.  相似文献   
35.
Mutations in the WRN gene lead to the Werner syndrome (WS), which resembles premature aging. Here, we hypothesize that genetic variations in the WRN gene may also influence aging-trajectories in the population at large. To test this hypothesis, we assessed the impact of the i1-C/T, L1074F and C1367R polymorphisms in the WRN gene on the occurrence of cardiovascular pathologies, on cognitive performance and on the risks of all-cause, cardiovascular and cancer mortalities in the population-based Leiden 85-plus Study. This prospective follow-up study includes 1,245 participants aged 85 years and older, with a total follow-up of 5,164 person-years. At baseline the risks of myocardial infarction, myocardial ischemia, intermittent claudication, arterial surgery and stroke dependent on the i1-C/T, L1074F and C1367R polymorphisms, did not vary between the different genotypes. Also no differences in cognitive functioning were observed, except for attention, where carriers of the 1367R allele performed worse compared to the 1367C homozygotes (94.2 (4.35) versus 84.8 (1.84), p=0.04). Mortality risks, calculated separately for all SNPs, were similar between the different genotype carriers of the i1-C/T, L1074F and C1367R polymorphisms, showing no evidence of altered survival. In conclusion, the i1-C/T, L1074F and C1367R polymorphisms in the WRN gene do not influence the aging-trajectories and survival in the population at large.  相似文献   
36.
ABSTRACT

Aloe ferox. Mill. is one of the plants used for the treatment of sexually transmitted infections (STIs) in the Eastern Cape province of South Africa. Different extracts of the plant were investigated for their antimicrobial constituents. This led to the isolation of three known compounds, namely, 1,8-dihydroxy-3-hydroxymethyl-9,10-anthracenedione (1, aloe-emodin), 1,8-dihydroxy-3-methyl-9,10-anthracenedione (2, chrysophanol), and 10-C.-β-D-glucopyranosyl-1,8-dihydroxy-3-hydroxymethyl-9-anthracenone (3, aloin A). The structures of the compounds were determined by chemical and spectroscopic studies. The antibacterial activity of the compounds (13) was demonstrated using the microplate dilution method.  相似文献   
37.
目的探讨补阳还五汤对肺纤维化大鼠的干预作用。方法将144只健康雄性SD大鼠采用随机数字表法分为假手术组、模型组、强的松组和补阳还五汤高、中、低剂量组,每组24只。除假手术组外,其余各组采用一次性气管滴注博莱霉素复制肺纤维化大鼠模型,假手术组气管内滴注等量生理盐水,造模第2日起,各给药组给予相应药物灌胃,于造模后第7、14、28日分3批处死动物,每次8只。分离血清,采用放免法检测各组大鼠血清Ⅲ型前胶原氨端肽(PCⅢ)、Ⅳ型胶原氨端肽(Ⅳ-C)的含量。结果与假手术组比较,各组大鼠血清PCⅢ、Ⅳ-C的含量逐渐升高,模型组最为明显(P〈0.01);与模型组比较,各给药组大鼠血清PCⅢ、Ⅳ-C含量均降低(P〈0.01);与强的松组比较,补阳还五汤中剂量组第14、28日及补阳还五汤低剂量组第28日时,PCⅢ、Ⅳ-C含量明显降低(P〈0.05)。结论补阳还五汤可以有效抑制肺组织中胶原纤维的增殖及细胞外基质的沉积,达到抗肺纤维化的作用。  相似文献   
38.
Elevated lipoprotein(a) (Lp[a]) is a causal genetic risk factor for cardiovascular disease. To determine if current evidence supports both screening and treatment for elevated Lp(a) in high-risk patients, an English-language search of PubMed and MEDLINE was conducted. In population studies, there is a continuous association between Lp(a) concentrations and cardiovascular risk, with synergistic effects when low-density lipoprotein (LDL) is also elevated. Candidates for Lp(a) screening include patients with a personal or family history of premature cardiovascular disease, familial hypercholesterolemia, recurrent cardiovascular events, or inadequate LDL cholesterol (LDL-C) responses to statins. Given the comparative strength of clinical evidence, reducing LDL-C to the lowest attainable value with a high-potency statin should be the primary focus of lipid-modifying therapies. If the Lp(a) level is 30 mg/dL or higher in a patient who has the aforementioned characteristics plus residual LDL-C elevations (≥70-100 mg/dL) despite maximum-potency statins or combination statin therapy, the clinician may consider adding niacin (up to 2 g/d). If, after these interventions, the patient has progressive coronary heart disease (CHD) or LDL-C levels of 160-200 mg/dL or higher, LDL apheresis should be contemplated. Although Lp(a) is a major causal risk factor for CHD, no currently available controlled studies have suggested that lowering it through either pharmacotherapy or LDL apheresis specifically and significantly reduces coronary risk. Further research is needed to (1) optimize management in order to reduce CHD risk associated with elevated Lp(a) and (2) determine what other intermediate- or high-risk groups might benefit from Lp(a) screening.  相似文献   
39.
A 49-year-old male presented with neck pain and deformity following an industrial accident sustained two months back. His neurology was normal except for a minimal weakness in left biceps (grade 4/5). Radiographs, magnetic resonance imaging and computed tomographic scan revealed fracture dislocation of C2-C3 with significant lateral translation of C2 over C3 without disc herniation. In view of unsuccessful closed reduction and absent disc herniation at the level of dislocation, a posterior only reduction, stabilisation and fusion with Iso-C 3D computer navigation-assisted cervical pedicle screw fixation with transverse rod-screw construct was performed. At 6 months followup the patient was completely relieved of his symptoms and was able to return to his previous occupation. The rare case is reported for the management by Iso-C 3D computer navigation assisted cervical pedicle screw fixation and reduction with transverse rod-screw construct at each involved level.  相似文献   
40.
We demonstrate the case of a surgery in a patient with irreducible atlantoaxial dislocation (IrAAD) after C2 fracture. The challenges of this case were the flexed head in a forced position, impossibility of neck extension, and revision operation after posterior occipito-cervical fixation. The patient underwent the following surgeries: 1. A ventral release of C1-C2 using transcervical endoscopy; 2. Removal of occipito-cervical system and fibrous block resection in the posterior surfaces of the C1-C2; 3. Reducing of AAD and odontoid screw fixation; 4. Posterior C1-C2-C3 screw fixation. Ankylosing of C1-C2 and C2-C3-C4 fusion was verified by computed tomography scan. There was an improvement in patient status as observed by the increase of the SF-36 scale scores.The use of endoscopic transcervical approach is a good alternative to the transoral approach. Comparative studies of these methods should be performed regarding the choice of an optimal method of decompression in cases of IrAAD.  相似文献   
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