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71.
Endoscopic ultrasound (EUS) is sensitive for staging gastrointestinal malignancies and pancreatic lesions. EUS‐fine‐needle aspiration (EUS‐FNA) offers a diagnostic accuracy of about 60–90% for pancreatic tumors and > 90% for lymph nodes. There are several limitations of EUS‐FNA including the need for on‐site cytopathology review. In addition, accuracy of cytologic review is hampered by the presence of blood, benign epithelial cells, desmoplasia, and well‐differentiated tumors. Furthermore, the small biopsy sample and destruction of tissue architecture limits the diagnostic sensitivity for GISTs and lymphomas. Many of these problems can be overcome with use of EUS trucut biopsy (TCB) needles. These large caliber, cutting needles acquire larger tissue samples allowing preservation of tissue architecture and histologic examination. Our recently described experience with EUS‐TCB initially in swine and later humans demonstrated the safety for acquiring histologic tissue representative of the target organs sampled enabling accurate diagnosis. These studies suggested greater diagnostic accuracy of EUS‐TCB for submucosal mass lesions and lymphoma and potentially the need for fewer needle passes for solid pancreatic neoplasms. In this paper we will review the current TCB literature, device design and technique, help troubleshoot potential problems, and offer opinion as to the utility and role of this new device. 相似文献
72.
L.I. Daikhin M. Urbakh 《Journal of electroanalytical chemistry (Lausanne, Switzerland)》2003,560(1):59-67
We develop a theory of the double layer at electrolyte–electrolyte interfaces taking in to account the microscopic structure of the interfacial region. This includes a “mixed boundary layer” where the overlapping of two space-charge regions occurs, and the effects of ion association and adsorption at the interface. Theoretical results are in good agreement with experimental data obtained for various organic solvents and electrolytes. The theory suggests a framework for the treatment of the capacitance data and establishes a relationship between experimental results and the microscopic structure of interfaces between two immiscible electrolyte solutions (ITIES). 相似文献
73.
经直肠超声引导前列腺穿刺活检203例临床分析 总被引:8,自引:1,他引:7
目的评估经直肠超声引导的前列腺六针穿刺活检在前列腺癌及前列腺其他疾病的诊断和鉴别诊断的价值。方法对指肛检查阳性,血清PSA〉4pg/L及经直肠超声检查前列腺声像图异常怀疑有占位性病变的203人进行经直肠超声引导的前列腺穿刺活检。结果穿刺活检的203例病理结果:良性前列腺增生(BPH)104例占51.24%,前列腺癌(PCa)95例占46.80%,前列腺结核及前列腺平滑肌肉瘤各2例,分别占0.98%。结论经直肠超声引导的前列腺穿刺活检其操作简单,病人痛苦小,并发症少,较安全。在前列腺癌及其他前列腺疾病的诊断与鉴别诊断中有重要的临床价值。 相似文献
74.
Severe axonal polyneuropathy with onset in the postpartum period 总被引:1,自引:0,他引:1
A. Vital M. Larrivière A. Lagueny E. Ellie X. Ferrer M. Dupon M. Barat J. M. Mazaux 《Acta neurologica Scandinavica》1994,89(4):303-306
We report two patients who presented severe polyneuropathy in the postpartum period. Electrophysiological studies evidenced an axonal process which was associated with proximal demyelination in the second patient. In both cases, a peripheral nerve biopsy showed severe axonal Wallerian-like degeneration and no feature of demyelination. The first patient had a dramatic loss of myelinated fibres, and severe disability persisted for several months. These two patients are different from cases of acute or chronic inflammatory demyelinating polyradiculoneuropathy previously reported in relation with pregnancy. 相似文献
75.
Neurogenic muscle hypertrophy in radiculopathy 总被引:1,自引:0,他引:1
The course of radiculopathy is sometimes associated with weakness and wasting of muscles. Very rarely in such cases, however, is hypertrophy of muscle fibres observed. Three cases are presented of sciatica with enlarged calves caused by hypertrophy of type 1 or types 1 and 2 muscle fibres. In light of the literature and the results obtained, an attempt is made to explain the cause of rare clinical symptoms and draw attention to diagnostic and therapeutic difficulties. 相似文献
76.
以液体稀释法比较了自制与进口十六烷基吡啶作用于4种口腔常见微生物的最低抑菌浓度和最低杀菌浓度的实验结果,经t检验证明两者间无显著差异,提示自制氯化十六烷基吡啶的药效质量可靠。并就控制接种菌量及杀菌机理等问题作了初步探讨。 相似文献
77.
Objective Report of two cases of exudative discoid and lichenoid dermatosis (Sulzberger-Garbe), with typical penile lesions. Differential diagnosis of persistent penile plaques. Background Following remission of the generalized eruption of exudative discoid and lichenoid dermatosis (Sulzberger-Garbe), it is not unusual to see a single remaining lesion localized on the penis. Since Sulzberger et al. (Sulzberger MB, Witten VH, Hunt JA. Puzzling persistent penile plaques. Arch Dermatol 1956:73:101-109) reviewed dermatoses presenting with puzzling persistent penile plaques in 1955, further dermatoses have evolved as important differential diagnoses. Much controversy has arisen as to the justification of exudative discoid and lichenoid dermatosis (Sulzberger-Garbe) as a disease entity. Conclusions Diagnosis of most cases of persistent plaques of dermatitis on the penis is possible with a careful examination of the entire skin, and a thorough history to discover past lesions. The possibility of malignancy makes a biopsy mandatory. Exudative discoid and lichenoid chronic dermatosis (Sulzberger-Garbe) typically responds well to systemic steroids. Intrale-sional triamcinolone acetonide has been demonstrated to be effective in the treatment of a persistent penile plaque in exudative discoid and lichenoid dermatosis (Sulzberger-Garbe), and may be helpful in discontinuing or reducing systemic therapy to a level compatible with long-term treatment. 相似文献
78.
Nerve biopsy findings in Niemann-Pick type II (NPC) 总被引:1,自引:0,他引:1
A. F. Hahn J. J. Gilbert C. Kwarciak J. Gillett C. F. Bolton C. A. Rupar J. W. Callahan 《Acta neuropathologica》1994,87(2):149-154
The severe infantile form of Niemann-Pick disease type II was diagnosed in a 4-year-old girl and confirmed by demonstrating in cultured skin fibroblasts a deficiency of low-density lipoprotein-stimulated cholesterol ester synthesis of < 5% of normal. Electrodiagnostic studies revealed changes of a predominantly demyelinating motor and sensory polyneuropathy. Light microscope and ultrastructural examination of a peroneal nerve biopsy showed unique changes. Compacted myelin sheaths were disproportionately thin with marked globular irregularities in single teased nerve fibres and evidence of chronic demyelination. The majority of axons were preserved but axonal spheroids and cytoskeletal abnormalities akin to neuroaxonal dystrophy were noted. Membrane-bound multilobulated lysosomal inclusions of floccular and electron-dense material were present in Schwann cells (SC), endoneurial fibroblasts, macrophages, pericytes and endothelial cells. SC of myelinated fibres were stuffed with whorls of concentric osmiophilic membranous profiles and electron-lucent material. The findings are diagnostic and differ from those of classical Niemann-Pick disease. 相似文献
79.
J. BYROM G. DOUCE† P.W. JONES‡ H. TUCKER J. MILLINSHIP K. DHAR & C.W.E. REDMAN 《International journal of gynecological cancer》2006,16(1):253-256
The reliability and applicability of colposcopically directed cervical punch biopsy was assessed in a sample of 170 paired punch and large loop excision of cervical transformation zone (LLETZ) specimens obtained from previously untreated women who had been selected for treatment on the basis of cytology and/or colposcopic findings and in whom the entire cervical transformation zone was visible. A single punch biopsy was taken immediately before the LLETZ, and all the specimens were reviewed by a single pathologist. Nine (5.3%) punch biopsies were inadequate. In terms of whether or not there was cervical intraepithelial neoplasia (CIN), the chance-corrected kappa analysis rated overall agreement as poor (kappa = 0.21, 95% confidence limits 0.02-0.39), whereas in terms of histologic grade, it was fair to moderate (kappa = 0.32, 95% confidence limits 0.23-0.42). Punch biopsy tended to underestimate the disease. The sensitivity and specificity of colposcopically directed punch biopsy for the detection of high-grade CIN was 74% and 91%, respectively, with positive- and negative predictive values of 97% and 48%, respectively. Two microinvasive and two intraepithelial glandular lesions were missed on punch biopsy. Punch biopsy should be avoided when high-grade disease is suspected. 相似文献
80.
Michelle Lucinda DeOliveira M.D. Tarcisio Triviño M.D. Ph.D. Gaspar de Jesus Lopes Filho M.D. Ph.D. 《Journal of gastrointestinal surgery》2006,10(8):1140-1143
Carcinoma of the papilla of Vater is classified as periampullary cancer representing 5% of all gastrointestinal tract malignancies.
Early and accurate diagnosis is important for those patients with a tumor of the papilla, as the prognosis is more favorable
than in other periampullary neoplasms. Endoscopically obtained biopsies from suspicious papillae can detect an early tumor,
although even for skilled pathologists it is often difficult to differentiate carcinomas from noninvasive lesions on the basis
of forceps biopsies. The purpose of this study was to assess the preoperative diagnostic accuracy of duodenoscopy appearance
and biopsy in all cases with suspicion of tumor. Thirty patients with suspicion of carcinoma of the papilla of Vater and with
final diagnosis established by pancreatoduodenectomy were included in this retrospective study. In each case, a comparison
was made between endoscopic biopsy and duodenoscopic appearance. Duodenoscopic appearance sensitivity and accuracy for malignancy
were 86% and 83%, respectively, whereas endoscopic biopsy sensitivity and accuracy were 65% and 67%, respectively. Although
preoperative diagnosis of carcinoma of the papilla of Vater is useful for making therapeutic decisions, the diagnostic value
of the endoscopic appearance was superior to endoscopic biopsy in this series.
Presented at the 2003 American Hepato-Pancreato-Biliary Association Congress, Miami, Florida, February 27-March 3, 2003.
Supported by FADA-CAPES/PROP 200J (M.L.D.). 相似文献