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41.
Spermon JR Ramos L Wetzels AM Sweep CG Braat DD Kiemeney LA Witjes JA 《Human reproduction (Oxford, England)》2006,21(7):1781-1786
BACKGROUND: While (partial) recovery of spermatogenesis, observed by means of standard semen analysis, has been seen in testicular cancer patients after chemotherapy with cisplatin, sperm genomic integrity and its implication for the patient's fertility are poorly understood. METHODS: Semen and serum from 22 patients treated for testicular cancer were analysed pre- and post-chemotherapy. Besides routine semen analysis, sperm samples were evaluated by computerized karyometric image analysis (CKIA), chromomycin-A3 assay (CMA3, chromatin condensation) and TdT-mediated dUTP nick-end labelling assay (TUNEL, DNA damage). Serum FSH, LH and testosterone concentrations were measured. RESULTS: Ejaculate volume decreased post-chemotherapy (P<0.05). External sperm characteristics (CKIA morphometry) and sperm counts did not deteriorate after chemotherapy. An improvement in DNA condensation was assessed after chemotherapy (37 versus 50% and 47.5 versus 63.7% for CMA3 and CKIA respectively; both P<0.005); yet a high percentage of TUNEL-positive sperm was found in the samples (21 versus 25% for pre- and post-chemotherapy samples respectively). These values were significantly higher than those of a convenience sample of normozoospermic males attending pre-IVF screening. Serum FSH and LH (IU/l) increased after chemotherapy compared with pretreatment levels (8.1 versus 16.7 and 4.5 vs 6.8; both P<0.05, respectively). CONCLUSIONS: Despite the improvement in sperm chromatin packaging after chemotherapy, an abnormally high percentage of DNA-damaged sperm was found in these samples. As sperm quality does not reach normal levels after treatment, it remains difficult to outline the best strategy and guidance concerning fertility potential of testicular cancer patients. 相似文献
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44.
Oculocutaneous albinism 总被引:2,自引:0,他引:2
JF Okulicz RS Shah RA Schwartz CK Janniger 《Journal of the European Academy of Dermatology and Venereology》2003,17(3):251-256
Oculocutaneous albinism represents a group of inherited skin disorders characterized by a generalized reduction of cutaneous, ocular and pilar pigmentation from the time of birth. Oculocutaneous albinism types 1 and 2 are the most common, but several other types have been described. A defect in the melanin synthesis pathway, resulting in reduced formation of melanin, is responsible for oculocutaneous albinism. Aetiology, clinical manifestations, diagnosis and management are discussed. 相似文献
45.
A prospective evaluation of color flow mapping and real-time ultrasound was performed to determine if pseudoaneurysms could be distinguished from other causes of masses surrounding vascular grafts of the lower extremities. Twelve palpable pulsatile masses were imaged. Diagnoses were confirmed at angiography (n = 11), computed tomography (n = 7), aspiration biopsy (n = 5), and operative intervention (n = 6). A swirling pattern of blood flow was seen in six of seven cases of pseudoaneurysm. Lack of flow signals was noted in four of the five collections representing hematoma (n = 2) or infection (n = 2). The seventh case was later shown to be an infected, thrombosed pseudoaneurysm. The single false-positive diagnosis was made early in the series when the flow signals detected were due to transmitted arterial pulsations. The authors conclude that color Doppler flow imaging is useful in the differential diagnosis of pulsatile masses associated with prosthetic grafts. Prosthetic graft pseudoaneurysms have a specific appearance of swirling blood flow arising from a wide neck and are distinguishable from traumatic or iatrogenic pseudoaneurysms of the native vascular tree. 相似文献
46.
Segmental dilatation of the small bowel is a rare congenital abnormality that occurs mainly in children and produces significant nonspecific symptoms. The authors reviewed 33 cases reported in the literature and present three new cases in which the lesion was demonstrated on radiographs obtained before laparotomy. These cases showed the spectrum of symptoms and characteristic radiologic features of this condition in both plain abdominal radiographs and barium studies. Plain radiographs of the abdomen may show an isolated loop of bowel containing an air-fluid level. The characteristic finding in barium studies of the small bowel is a localized dilatation of the small bowel lumen with afferent and efferent loops. In the absence of a complication or coexistent cause of obstruction, the transit time of contrast medium through the small bowel is not delayed. The radiologic examination is useful in diagnosis, and the condition is cured with surgery. 相似文献
47.
Grüntzig balloon catheters were used to dilate ten esophageal strictures in eight infants and children. Five infants who had anastomotic strictures following esophageal atresia repair gained complete resolution of their strictures, usually after one or two dilatations. Three older children who had strictures following esophageal re-operation or reconstruction required longer courses of dilatations to achieve consistent esophageal patency. The technique failed in two chronic strictures of two and one-half and nine years' duration. Balloon catheter dilatation, begun in the early postoperative period, is a safe, effective method for dilating esophageal strictures. 相似文献
48.
Coronary artery bypass grafts: visualization with MR imaging 总被引:1,自引:0,他引:1
49.
The magnetic resonance (MR) relaxation rates of protons were compared in the myelinated and nonmyelinated nerves of the garfish. The long, large olfactory nerve of the garfish, as an easily accessible source of nonmyelinated axons, is uniquely suited for such a comparison. The T1 and T2 measurements revealed distinct and consistent differences between nonmyelinated olfactory nerves and myelinated optic and oculomotor nerves. Comparisons between water content, lipid content, and relaxation rates indicated that the differences in MR properties represent complex differences in the distribution and physical environment of the constituent lipid and water protons. 相似文献
50.
Intestinal obstruction proximal to a transition zone without an interposed physical barrier usually indicates Hirschsprung disease. The authors report one case of focal small bowel muscular thinning just distal to a transition zone that produced clinical and radiographic findings that simulated long-segment Hirschsprung disease in a 2-day-old infant. 相似文献