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61.
Miguel A. Rodriguez-Bigas MD Remedios B. Penetrante MD Lemuel Herrera MD Nicholas J. Petrelli MD 《Gastrointestinal endoscopy》1995,42(6)
Background: In familial adenomatous polyposis and juvenile polyposis, polyps can occur throughout the gastrointestinal tract.Methods: We report seven patients with familial adenomatous polyposis and two patients with juvenile polyposis who underwent small bowel enteroscopy at the time of exploratory celiotomy either for colectomy or other pathology.Results: Polyps in the jejunum and/or ileum were noted in five of nine (56%) patients at enteroscopy. In three of nine (33%) patients these polyps were adenomatous. Two of these patients had polyps in the jejunum and in the ileum, whereas one patient had jejunal adenomas alone. These polyps were from 3 mm to 30 mm in size. The remaining two patients with polyps had lymphoid hyperplasia in the ileum. All three patients who had adenomas at intraoperative small bowel enteroscopy had duodenal adenomas at esophagogastroduodenoscopy. At the age of 14 years, one patient had an intramucosal carcinoma in a small bowel juvenile polyp.Conclusion: Baseline small bowel enteroscopy should be considered at the time of surgical exploration in patients with asymptomatic familial adenomatous polyposis and juvenile polyposis. In patients with duodenal polyps, enteroscopy should be performed at the time of surgery. Biopsy and/or excision of larger polyps should be performed because these polyps may harbor a carcinoma. (Gastrointest Endosc 1995;42:560-4.) 相似文献
62.
A LONG PERSPECTIVE ON CHILDHOOD MULTIPLE SCLEROSIS 总被引:5,自引:1,他引:4
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65.
D K Williams D R Carlton S H Green K Pearman T R Cole 《Journal of medical genetics》1997,34(10):842-845
We report a child of 3 years 9 months with the Marshall-Smith syndrome (MSS), characterised by the typical facial features, developmental delay, and advanced bone age. After the diagnosis was made at 5 months of age, careful observation for respiratory complications and failure to thrive was initiated. By 3 1/2 years of age, although our patient had no life threatening respiratory complications, investigation showed significant upper airway obstruction, which has been successfully treated. Aggressive treatment for failure to thrive has also allowed her to maintain a weight on the 50th centile. The purpose of this report is to suggest that early diagnosis and aggressive management may improve the ultimate prognosis with respect to the respiratory and feeding difficulties seen in this rare syndrome. 相似文献
66.
Manoussos M. Konstadoulakis MD Michael Vezeridis MD Emi Hatziyianni MD Constantine P. Karakousis MD PhD Bernard Cole PhD Kirby I. Bland MD Harold J. Wanebo MD 《Annals of surgical oncology》1998,5(3):253-260
Background: Oncogenes and other molecular tumor markers that predict tumor aggressiveness may allow individualization and optimization of surgical therapy of intermediate-thickness malignant melanoma. We examined the expression of selected markers, including the HLA-DR antigen, the heat shock protein-70 (HSP-70), and the c-myc oncogene in primary melanoma and regional nodes and related these findings to metastatic potential and survival.
Methods: Forty patients with primary melanoma (1.5–4.0 mm) were studied, all of whom had prophylactic lymph node dissection and were followed for 18 months to 7 years. The primary tissue and nodes were examined using immunohistochemical techniques for the presence of HLA-DR antigen and HSP-70 protein and the expression of the c-myc oncogene.
Results: Of 40 patients, there were 23 with lesions 1 to 2.9 mm thick and 17 with lesions 3 to 4 mm thick. Nodal metastases were present in 25 of the 40 patients who had elective node dissection. HLA-DR antibody stained the primary tumor in 10 patients (25%), but there was no correlation with survival in this group. HLA-DR antibody stained the stroma and cellular infiltrates surrounding the primary tumor in 28 of 40 patients; in this group there was a correlation of HLA-DR staining of the peritumoral stroma with improved survival overall. HLA-DR staining of the peritumoral stroma also influenced survival when patients were stratified by tumor thickness groups 1 to 2.9 mm and 3 to 4 mm and presence of nodal metastases. HSP-70 was demonstrated in the primary tumor in 25% of patients, who were also shown to have significantly improved survival when compared with those whose primary tumor did not stain with HSP-70. C-myc was expressed in the primary tumor in 25%, but showed no correlation with survival. None of these proteins correlated with or predicted the presence of nodal metastases.
Conclusion: We conclude that the use of specific molecular-oncogene markers in intermediate-thickness primary melanoma may identify patients at high risk for conventional treatment failure and reduced survival who may profit from more aggressive surgery, adjuvant therapy, or both.Presented at the 48th Annual Cancer Symposium of The Society of Surgical Oncology, Boston, Massachusetts, March 23–26, 1995. 相似文献
67.
68.
Biosynthesis of the antibiotic actinorhodin. Analysis of blocked mutants of Streptomyces coelicolor 总被引:6,自引:0,他引:6
From two types of class V act mutants of Streptomyces coelicolor two monomeric precursors of actinorhodin have been isolated and their structures determined. One is the known antibiotic kalafungin and the other a new compound. Their relationship to actinorhodin biosynthesis is discussed. 相似文献
69.
Guochuan Tsai Hsien-Yuan Lane Pinchen Yang Mian-Yoon Chong Nicholas Lange 《Neuropsychopharmacology》2004,55(5):452-456
BACKGROUND: Hypofunction of N-methyl-D-aspartate glutamate receptor had been implicated in the pathophysiology of schizophrenia. Treatment with D-serine or glycine, endogenous full agonists of the glycine site of N-methyl-D-aspartate receptor, or D-cycloserine, a partial agonist, improve the symptoms of schizophrenia. N-methylglycine (sarcosine) is an endogenous antagonist of glycine transporter-1, which potentiates glycine's action on N-methyl-D-aspartate glycine site and can have beneficial effects on schizophrenia. METHODS: Thirty-eight schizophrenic patients were enrolled in a 6-week double-blind, placebo-controlled trial of sarcosine (2 g/d), which was added to their stable antipsychotic regimens. Twenty of them received risperidone. Measures of clinical efficacy and side effects were determined every other week. RESULTS: Patient who received sarcosine treatment revealed significant improvements in their positive, negative, cognitive, and general psychiatric symptoms. Similar therapeutic effects were observed when only risperidone-treated patients were analyzed. Sarcosine was well-tolerated, and no significant side effect was noted. CONCLUSIONS: Sarcosine treatment can benefit schizophrenic patients treated by antipsychotics including risperidone. The significant improvement with the sarcosine further supports the hypothesis of N-methyl-D-aspartate receptor hypofunction in schizophrenia. Glycine transporter-1 is a novel target for the pharmacotherapy to enhance N-methyl-D-aspartate function. 相似文献
70.
Shafi Mussa Tash Prior Nicholas Alp Kathryn Wood Keith M Channon David P Taggart 《European journal of cardio-thoracic surgery》2004,26(5):988-994
OBJECTIVE: Radial arteries are increasingly used as conduits for coronary artery bypass grafts, but perioperative graft vasospasm remains a concern. In vitro testing has demonstrated the efficacy of phenoxybenzamine and verapamil/nitroglycerin as topical antispasmodic agents, but their duration of action in vivo is unknown. Using an in vivo mouse model, we measured their duration of action in functioning vascular grafts, and compared this to their in vitro duration of action in ungrafted vascular segments. METHODS: Two millimetre mouse aortic segments (C57/BL6) were incubated with phenoxybenzamine, verapamil/nitroglycerin, or buffer (controls) for 15 min in organ chambers. Isometric tension responses to phenylephrine and prostaglandin F2alpha were measured at 0, 2, 6 and 12 h post-incubation. In parallel, 36 murine infrarenal aortic interposition grafts (2 mm) were performed. Twelve grafts were pre-treated (15 min) with phenoxybenzamine, 12 with verapamil/nitroglycerin and 12 remained untreated (controls). Isometric tension responses to the same agonists were measured in grafts harvested 2, 6, 13 and 23 h after surgery. RESULTS: Phenoxybenzamine prevented alpha-adrenergic vasoconstriction for up to 16 h in vivo (grafts), and 12h in vitro (ungrafted segments). Verapamil/nitroglycerin was effective for at least 2 h in vitro, but did not prevent vasoconstriction after 2 h in vivo. CONCLUSIONS: The mouse model appears to be a useful technique for assessing the pharmacological properties of antispasmodic agents in vivo. Phenoxybenzamine has an extended action in arterial grafts in vivo. Verapamil/nitroglycerin is short-lived in vivo but lasts longer in vitro. Measurements of antispasmodic duration of action in vitro should be interpreted with caution. 相似文献