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91.
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We describe a case of a previously irradiated infantile hemangioma in a patient 1 year of age. At the age of 78, the patient presented with a pink, pearly plaque at the previously irradiated infantile hemangioma site and was found to have a nodular basal cell carcinoma. [Correction added on 30 August 2023, after first online publication: In the preceding sentence, patient age has been corrected in this version] This case highlights the rare, but long-term risks of radiation therapy for hemangiomas, but also presents an interesting historical vignette in dermatological treatments, with photographic documentation. It also represents the longest time interval between irradiation of an infantile hemangioma and the development of a basal cell skin cancer, 70 years in this case.  相似文献   
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A dermold cyst, arising from the posterior aspects of the prostate and seminal vesicles, and extending into the pelvis to masquerade as a full bladder, must be exceedingly rare. Ultrasound, computed tomography and especially magnetic resonance imaging (MRI) proved to be invaluable in making the diagnosis, and MRI in particular was very useful in providing an anatomical road map for surgery.  相似文献   
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The goal of this study was to identify an injectable anesthetic protocol that provides sedation sufficient for peripheral vascular catheterization, intubation, and transport while minimizing cardiovascular changes in Yorkshire and Yucatan pigs with and without cardiovascular injury and intervention (CI). Phase 1 examined the safety and efficacy of acepromazine–ketamine, diazepam–ketamine, midazolam–ketamine, and medetomidine–ketamine in 5 healthy Yorkshire pigs. For each drug combination, we obtained multiple measurements of heart rate, blood pressure, respiratory rate, temperature, sedation score, ability to catheterize and intubate, and recovery score. Phase 2 evaluated and refined the dose of the most effective Phase 1 anesthetic combination (midazolam–ketamine) in healthy and CI Yorkshire pigs (n = 53 trials). Phase 3 mirrored Phase 2 but tested midazolam–ketamine in healthy and CI Yucatan pigs (n = 34 trials). Midazolam (0.5 mg/kg)–ketamine (25 to 27 mg/kg) was the most effective anesthetic combination in healthy Yorkshire pigs, but this dose was less effective in healthy Yucatan pigs and CI Yorkshire and Yucatan pigs. Midazolam–ketamine resulted in tachycardia and apnea more frequently in CI pigs than healthy pigs. This combination also caused vomiting in one CI Yucatan pig. Overall, midazolam–ketamine provided safe and effective sedation for catheterization and intubation of both healthy and CI pigs. This study suggests Yucatan pigs may require a higher dose midazolam–ketamine to achieve the same level of sedation as that in Yorkshire pigs. Although anesthetic complication rates were higher in CI pigs, our results indicate that midazolam–ketamine can be safely used for sedation of both pig breeds with and without CI.Abbreviation: CI, cardiovascular injury and interventionPigs (Sus scrofa) are common models of cardiovascular injury and intervention (CI) that largely have replaced traditional canine cardiology models. Advantages of swine compared with dogs include anatomic and physiologic characteristics similar to humans, such as similar coronary artery distribution and effective collateralized blood flow to the myocardium after coronary artery blockage.23 However, pigs are difficult to restrain and anesthetize due to their size and resistance to sedative drug combinations, including those with morphine.24 Injectable sedative drugs may result in cardiovascular and respiratory effects such as increased cardiac work and oxygen consumption, tachycardia, bradycardia, apnea, hypertension, and hypotension.5,6,8-12,14,19,20,25-29 These side effects can pose considerable problems for CI pigs, and anesthesia protocols with minimal effects on cardiovascular function are needed. A literature review revealed no published studies of anesthetic protocols in swine with existing cardiovascular injury; published research is limited to investigating anesthesia protocols for experimental induction of CI or determining in vitro and in vivo drug effects on healthy cardiovascular systems.4-6,8-12,14,19-21,25-29 Other published studies have limited investigations to studying sedative and physiologic effects in healthy Yorkshire, Yucatan, mixed-breed, Landrace, and Gottingen miniature swine.2,3,10,13,17,18,20-22We conducted the current study to address the need for a systematic investigation of anesthetic protocols in CI Yorkshire and Yucatan pigs. The goals of this study were to determine an injectable-only anesthetic protocol for both Yorkshire and Yucatan pigs that yielded sufficient sedation for peripheral vascular catheterization, sufficient duration for transport, and minimal cardiovascular effects while being safe and effective for CI pigs.  相似文献   
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用放射配体受体结合试验法,研究了新化合物三环哌酯与人大脑皮质M受体的结合特性,并与QNB作了比较。饱和实验结果显示,[3H]三环哌酯的结合参数与[3H]QNB相近,两种配体的作用均符合单位点模型。竞争性抑制实验结果表明二者作用强度相当。[3H]三环哌酯的结合和解离速率常数均较[3H]QNB大,且其与皮质M受体的解离受季铵酚的变构调节,结果提示,两种配体与M受体有一些不同的结合特性,在M受体研究中,[3H]三环哌酯可以作为[3H]QNB的补充工具。  相似文献   
99.
Inactivation of the p53 tumor suppressor gene has been implicated in the pathogenesis of numerous human cancers, including osteosarcomas. Appendicular osteosarcomas of the dog appear to be a good model for their human equivalent with regard to biologic behavior, epidemiology and histopathology. We individually screened exons 5-8 of the p53 gene for mutations in 15 canine appendicular osteosarcomas using 'Cold' SSCP to compare the role of this gene in human and canine osteosarcoma tumorigenesis. Seven of the tumors (47%) exhibited point mutations, with one tumor possessing two mutations within different exons. Of these, seven were missense mutations and the eighth was a 'silent' mutation potentially affecting the exon 6-7 splicing region. Five of the missense mutations were located in highly conserved regions IV and V, while another corresponded with the highly conserved codon 220 mutational hotspot located outside the conserved domains. The locations and types of mutations were nearly identical to those reported in human cancer. These findings provide strong evidence of the involvement of p53 mutations in the development of canine appendicular osteosarcomas. Canine osteosarcomas appear to be a promising model for their human equivalent on a clinical, pathologic, and molecular level.   相似文献   
100.
The present study investigated the effects of dietary oltipraz on cigarette smoke-related lipophilic DNA adduct formation. Female Sprague- Dawley rats were exposed daily to sidestream cigarette smoke in a whole- body exposure chamber 6 h/day for 4 consecutive weeks. One group of rats was maintained on control diet while another group received the same diet supplemented with either a low (167 p.p.m.) or high (500 p.p.m.) dose of oltipraz, starting 1 week prior to initiation of smoke exposure until the end of the experiment. Analysis of lipophilic DNA adducts by the nuclease P1-mediated 32P-post-labeling showed up to five smoke-related adducts. Adduct no. 5 predominated in both the lung and the heart while adduct nos 3 and 2 predominated in the trachea and bladder, respectively. Quantitative analysis revealed that the total adduct level was the highest in lungs (270+/-68 adducts/10(10) nucleotides), followed by trachea (196+/-48 adducts/10(10) nucleotides), heart (141+/-22 adducts/10(10) nucleotides) and bladder (85+/-16 adducts/10(10) nucleotides). High dose oltipraz treatment reduced the adduct levels in lungs and bladder by >60%, while the reduction in lungs in the low-dose group was approximately 35%. In trachea, the effect of low and high dietary oltipraz on smoke DNA adduction was equivocal, while smoke-related DNA adducts in the heart were minimally inhibited by high-dose oltipraz. In a repeat experiment that employed a 3-fold lower dose of cigarette smoke, oltipraz (500 p.p.m.) was found to inhibit the formation of DNA adducts in rat lungs and trachea by 80 and 65%, respectively. These data clearly demonstrate a high efficacy of oltipraz in inhibiting the formation of cigarette smoke-induced DNA adducts in the target tissues.   相似文献   
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