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21.
Balanitis xerotica obliterans in children   总被引:1,自引:0,他引:1  
Balanitis xerotica obliterans was studied in 48 fully developed and 6 early cases in children aged 2-15 years. It occurred in 9% of 100 consecutive circumcisions for all, including religious, reasons and in 19% of 232 other circumcisions for disease of the prepuce and penis. Seven cases developed after surgery for hypospadias. The boys nearly always presented with inability to retract the prepuce; half also had discomfort after micturition, and a quarter had obstructive signs, usually minor. At surgery, half had involvement of glans or meatus, previously considered rare in childhood, 3 requiring meatotomy. The condition, once seen, was easily recognized clinically as well as microscopically. The early cases, characterized by focal narrow hyaline edematous zones in severe diffuse chronic balanitis, suggest that the condition may be an inflammation in which the usual increased permeability of small vessels in inflammatory reaction is accentuated in a loose vascular region.  相似文献   
22.
OBJECTIVES AND STUDY DESIGN: Squamous cell carcinomas are common malignancies and a major cause of mortality. The molecular mechanisms involved in tumorigenesis remain largely unknown, but sequence alterations have been identified in coding regions of several genes. Primary squamous cell carcinomas of various tissues (skin, head and neck, esophagus, lung, penis, uterus, and vagina) from 52 patients were analyzed for the presence of mutations within several candidate genes presumably involved in tumorigenesis: Gsalpha, Gi2alpha, GTPase activating protein (GAP), and patched (PTCH) genes. METHODS: Mutational analysis scheme included polymerase chain reaction (PCR), denaturing gradient gel electrophoresis (DGGE), single stranded conformational polymorphism (SSCP), and selected sequence analysis. RESULTS AND CONCLUSION: No tumor had any evidence of mutations in any of these analyzed genes. Mutations within these genes do not occur frequently in an unselected population of patients with squamous cell carcinomas.  相似文献   
23.
PURPOSE: To determine the feasibility of using ultrasonography (US) for evaluation of a radial nerve injury associated with humeral shaft fracture. MATERIALS AND METHODS: In a prospective study, 11 consecutive patients with sensorimotor radial deficiency after distal humeral fracture were evaluated with conventional radiography, US, electroneurography, and electromyography. Surgical repair of the fracture and nerve inspection were performed in five patients. The remaining six patients were successfully treated conservatively. The US appearance of the radial nerve was studied in 10 healthy volunteers and in the noninjured arm of the 11 patients for comparison. RESULTS: In five patients, US findings of a severely damaged radial nerve were confirmed at surgical nerve inspection. In one patient, the nerve was entrapped between fragments. One patient had a complete nerve dissection, one had a lacerated nerve from a loose compression plate, and one had a nerve riding on the edge of a bone fragment. In the fifth patient who underwent surgical inspection, the nerve was buried in the callus. In the six patients treated conservatively, US showed continuity of the nerve. CONCLUSION: US may be useful for accurate evaluation of the radial nerve in patients with nerve palsy associated with humeral shaft fracture.  相似文献   
24.
The objective of this article was to review the different factors and limitations influencing the accuracy of computer-aided implant surgery. In vitro and in vivo accuracy studies of articles and congress proceedings were examined. Similar results using bur tracking as well as image-guided template production techniques have been reported, and both methods allow for precise positioning of dental implants. Compared to the conventional technique, this sophisticated technology requires substantially more financial investment and effort (computerized tomographic imaging, fabrication of a registration template, intraoperative referencing for bur tracking, or image-guided manufacturing of a surgical template) but appears superior on account of its potential to eliminate possible manual placement errors and to systematize reproducible treatment success. The potential for the protection of critical anatomic structures and the esthetic and functional advantages of prosthodontic-driven implant positioning must also be considered. However, long-term clinical studies are necessary to confirm the value of this strategy and to justify the additional radiation dose, effort, and costs.  相似文献   
25.
Purpose The aim of this study was to assess the value of multimodality imaging using a novel repositioning device with external markers for fusion of single-photon emission computed tomography (SPECT) and computed tomography (CT) images. The additional benefit derived from this methodological approach was analysed in comparison with SPECT and diagnostic CT alone in terms of detection rate, reliability and anatomical assignment of abnormal findings with SPECT.Methods Fifty-three patients (30 males, 23 females) with known or suspected endocrine tumours were studied. Clinical indications for somatostatin receptor (SSTR) scintigraphy (SPECT/CT image fusion) included staging of newly diagnosed tumours (n=14) and detection of unknown primary tumour in the presence of clinical and/or biochemical suspicion of neuroendocrine malignancy (n=20). Follow-up studies after therapy were performed in 19 patients. A mean activity of 400 MBq of 99mTc-EDDA/HYNIC-Tyr3-octreotide was given intravenously. SPECT using a dual-detector scintillation camera and diagnostic multi-detector CT were sequentially performed. To ensure reproducible positioning, patients were fixed in an individualised vacuum mattress with modality-specific external markers for co-registration. SPECT and CT data were initially interpreted separately and the fused images were interpreted jointly in consensus by nuclear medicine and diagnostic radiology physicians.Results SPECT was true-positive (TP) in 18 patients, true-negative (TN) in 16, false-negative (FN) in ten and false-positive (FP) in nine; CT was TP in 18 patients, TN in 21, FP in ten and FN in four. With image fusion (SPECT and CT), the scan result was TP in 27 patients (50.9%), TN in 25 patients (47.2%) and FN in one patient, this FN result being caused by multiple small liver metastases; sensitivity was 95% and specificity, 100%. The difference between SPECT and SPECT/CT was statistically as significant as the difference between CT and SPECT/CT image fusion (P<0.001). Twenty-seven abnormal SPECT findings in 17 patients could not be initially assigned to organs, but were clearly delineated after image fusion. In 21 patients (40%), clinically relevant information was obtained by image fusion as compared with SPECT alone.Conclusion Co-registration of SPECT and diagnostic CT using a cost-effective immobilisation device provides excellent accuracy for tumour detection of endocrine malignancies and is superior to SPECT and CT alone. Image fusion reduces false positive results and can detect additional lesions. Anatomical information provided by CT enables precise localisation of abnormalities observed in SPECT.  相似文献   
26.
We prospectively audited 79 patients undergoing primary knee or hip arthroplasty (38 knees, 41 hips) and found that 66% (58% of knees, 73% of hips) had at least one unit of blood transfused postoperatively, with a mean transfusion requirement of 13 units per patient (1.1 for knees, 0 to 6; 1.5 for hips, 0 to 4). We then established a new protocol for postoperative blood transfusion. This requires the calculation of the maximum allowable blood loss (MABL) that each individual patient can safely lose based upon their weight and preoperative haematocrit. The total blood loss up to this volume is replaced with colloid. When a patient's total blood loss reaches their MABL their haematocrit is measured at the bedside using the Microspin system (Bayer plc, Newbury, UK). If their haematocrit is low (< 0.30 for men, < 0.27 for women), blood is transfused. As a safety net all patients have their haemoglobin formally checked on days 1, 2, and 3 after surgery and have a transfusion if the haemoglobin levels are less than 8.5 g/dl. We conducted a further audit of 82 patients (35 knees, 47 hips) after the introduction of this protocol. Under the new protocol only 24% of patients required blood (11% of knees, 34% of hips) with a mean transfusion requirement of 0.56 units per patient (0.26 for knees, 0 to 4; 0.79 for hips, 0 to 4). The use of clinical audit and the introduction of strict guidelines for transfusion can change transfusion practice and result in improved patient care. Our transfusion protocol is a simple and effective method of keeping transfusion to a minimum and is particularly useful in departments which do not have the facility to use autologous blood or reinfusion drains for relective orthopaedic surgery.  相似文献   
27.
BACKGROUND: Salt Lake City, Utah has seen a continuing resurgence of rheumatic fever (RF) since 1985. METHODS: emm genotyping and multilocus sequence typing of streptococcal isolates from periods of increased RF activity were performed. RESULTS: Multiple genotypes were present during 1985 and 1998, two peak years of RF activity, and in 1992, a year with reduced RF activity. emm3 and emm18.1 were present in 1985 and 1998, but not in 1992. Two other emm types, 12 and L28, were significantly elevated in 1998 (a peak RF year) over 1992 (a non-peak RF year). Allelic profiles for the emm3 and emm18.1 isolates exhibited clonality. CONCLUSIONS: During years of increased RF activity multiple emm types, including emm18.1 and emm3, were circulating in the community. During a year of decreased RF activity, emm3 and emm18.1 genotypes were absent. The clonality of the emm3 and emm18.1 types suggests that specific clones of both types are important in the resurgence of RF during these peak years. Two other genotypes, emm12 and emmL28, may also be associated with the persistence of RF in the Salt Lake City, UT area.  相似文献   
28.
We report on a girl with an abnormal hybridization pattern for the subtelomeric fluorescence in-situ hybridization (FISH) probe panel showing deletion of the long arm telomeric region of chromosome 6. All other subtelomere DNA probes showed normal hybridization patterns. Metaphase cells analysed from cultures of peripheral blood revealed a normal female chromosome complement at the 650-band level. The deletion was further characterized using genomic microarray analysis. Clinical findings include: developmental delay, seizures, hypoplasia of the corpus callosum, dextrocardia, unusual dimpling of knees and elbows, and minor anomalies. We are aware of only two other reports of isolated cryptic 6q subtelomeric deletions not associated with other chromosomal abnormalities. The absence of retinal abnormalities in our case supports the theory that genes responsible for the retinal abnormalities in other terminal 6q deletions are proximal to 6q27. Subtelomeric FISH probes were useful in establishing a diagnosis in our patient. As more cases are reported, we may be able to establish discrete phenotypes and natural histories that can aid in counselling families.  相似文献   
29.
This paper reports on a sporadic, naturally acquired infection of sheep with Brucella abortus on a privately owned farm in Toro near Bauchi, Nigeria. The abortions, which occurred in a flock of 28 Yankassa sheep, involved five ewes at the third month of gestation. Serum and milk samples from the flock were examined for Brucella antibodies by the Rose Bengal plate test, serum agglutination test (SAT) and milk ring test (MRT). The proportion shown as positive by SAT was 14.3%. All the five milk samples examined by MRT were positive. A total of seven isolates of Brucella were obtained from three milk samples and four vaginal swabs collected from aborting ewes. All isolates were identified and biotyped as B. abortus biovar 1. This biovar was also isolated from cattle maintained on the farm in association with the sheep. The infection was attributed to the animal husbandry practices employed on the farm.  相似文献   
30.
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