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71.
Jitter analysis in single fiber EMG (SFEMG) is usually done on-line during recording. However, this technique frequently prolongs the study and makes re-analysis impossible. We attempted to measure jitter with a high speed FM tape recorder and compare the results with the previously published values. SFEMG data, acquired with voluntary activation on extensor digitorum communis muscle of 25 healthy relatives of children with myasthenia gravis were retrospectively analyzed. Fiber density (FD) was estimated on-line. Five to 18 single fiber action potential (SFAP) pairs were studied in each subject. The wow of the tape recorder was 6 microseconds. Mean (SD) (upper 95th percentile) FD, individual jitter, highest jitter, mean jitter and interspike interval were 1.60 (0.18) (1.90), 25.30 (11.20) (57.00) microseconds, 31.24 (6.87) (47.00) microseconds, 25.08 (5.04) (43.00) microseconds, and 0.67 (0.11) (0.91) ms respectively. Mean jitter in the pooled SFAP pairs and mean MCD were found to be lower than the published values of the Ad Hoc Committee of the AAEM Special Interest Group on Single Fiber EMG. A high speed FM tape recorder can be reliably used for the off-line analysis of jitter.  相似文献   
72.
Adenosquamous carcinomas are rare malignant tumors of the pancreas and periampullary region. We present two cases of pancreatic and periampullary adenosquamous carcinoma with clinicopathologic, histo- and immunohistochemical findings. A 51-year-old and a 48-year-old man presented with right upper quadrant pain of three months duration and jaundice for two weeks. Both cases had an elevation of liver enzymes and CA 19-9. In the first case, computerized tomography showed a 3 cm-mass at the pancreatic head. In the second one, endoscopic retrograde choledocopancreatography (ERCP) revealed a mass at the ampulla Vateri localization. A pancreatoduodenectomy was performed for both cases. Gross pathologic examination displayed a solid, gray-white colored 4 cm-tumor at the pancreatic head and a solid, pink-white colored, 2 cm-tumor at the periampullary region bulging into the duodenal lumen. Microscopically, both tumors were composed of solid nests of squamous cells with pearl formation and mucin-containing glandular cells and diagnoses were adenosquamous carcinoma. Furthermore, histo- and immunohistochemical findings were consistent with microscopic diagnoses.  相似文献   
73.
This study describes the genetic relationships and antimicrobial resistance determinants found among 99 clinical isolates of enterococci from 15 different hospitals in Cuba. Pulsed-field gel electrophoresis SmaI analysis demonstrated a high degree of genetic diversity. A limited number of multiresistant Enterococcus faecalis clones, showing resistance to three or more families of antimicrobial agents, were detected simultaneously in different institutions, suggesting inter-hospital circulation of selected clones, and/or selection of particular clones following their introduction into the hospital environment. Antimicrobial resistance determinants, including erm(B), aac(6')-aph(2'), aph(3'), ant(6), vanB (E. faecalis) and vanA (Enterococcus faecium) were detected by PCR in various isolates.  相似文献   
74.
Several problems in the management of life-threatening mucormycosis remain unresolved, necessitating new methods of management. Four patients with histopathologically proven rhinocerebral mucormycosis were treated with high cumulative doses of granulocyte colony-stimulating factor (G-CSF). All had multiple predisposing factors for mucormycosis, particularly leukemia and neutropenia. Two patients refractory to fluconazole therapy were treated with liposomal amphotericin B. The improvement in clinical manifestations was closely related to neutrophil recovery, and all patients were alive at the end of therapy. In addition to surgical debridement and antifungal therapy, G-CSF seems to have played a role in their survival.  相似文献   
75.
Bordetella pertussis bacterial cells, bacterial extracts, and concentrated culture supernatant fluid were comparatively examined for histamine sensitizing and leucocytosis promoting activities, toxicity (mouse weight gain test), immunoprotective potency and lipopolysaccharide bioassay. The activity of histamine sensitizing factor always paralleled that of leucocytosis promoting factor. In contrast, important differences were demonstrated regarding the toxicity and protective activity of the three preparations. Culture supernatant was more toxic and less protective than either bacterial cells or cell extract. Although the latter had lower protective potency than whole cells, its lower toxicity might lead to its consideration as a possible potential vaccine.  相似文献   
76.
The occurrence of P fimbriae in a total of 222 uropathogenic Escherichia coli (UPEC) strains was investigated. Out of the total, 31 (14%) were P fimbriated. Of 24 pyelonephritogenic E. coli strains, three (13%) with P fimbriae occurred in children with clinical pyelonephritis, and of 198 E. coli strains 29 (15%) occurred in children with cystitis. Prevalence of P fimbriae of E. coli strains was found to be quite similar in patients with cystitis and pyelonephritis  相似文献   
77.
Situated on mature B lymphocytes, CDw75 antigen is a sialylated carbohydrate epitope generated by the enzyme beta-galactosyl alpha-2,6-sialyltransferase. Although CDw75 antigen expression was found to be correlated with aggressive behaviour of tumour cells in gastric adenocarcinomas, its prognostic role still remains unknown. The objective of this study was to determine the value of CDw75 antigen expression as a marker of the metastatic potential and prognosis of gastric adenocarcinomas. CDw75 antigen expression was evaluated immunohistochemically in 64 tumours and their nodal metastases. The correlation was analysed between CDw75 antigen expression and selected clinicopathological variables, including survival. Positive staining was detected in 31 cases. Non-neoplastic gastric mucosa was consistently negative. CDw75 expression was correlated with larger tumour size (p<0.006), infiltrative growth pattern (p<0.044), advanced stage (p<0.0006), and positive lymph nodes (p<0.0003).The overall survival rate of patients with CDw75 expression was 28%, which was significantly worse than that of patients without CDw75 expression (53%) (p<0.0005). Multivariate analysis showed that CDw75 expression was an independent prognostic indicator, together with the growth pattern of the tumour. These results indicate that immunohistochemical detection of CDw75 antigen expression may be a good indicator of metastatic potential and of prognosis in patients with gastric carcinomas.  相似文献   
78.
BACKGROUND: Data on the efficacy of pimecrolimus cream 1% within the first days of treatment are scarce, as in previous studies, the first postbaseline assessment was performed only after 1 week. OBJECTIVE: We sought to investigate the onset of action of pimecrolimus cream 1% in infants with mild to very severe atopic eczema. METHODS: We used pimecrolimus cream 1% (n = 129) or vehicle cream (n = 66) administered in a double-blind manner for 4 weeks and then open-label pimecrolimus cream 1% for 12 weeks, with a 4-week follow-up period. RESULTS: Pimecrolimus cream 1% reduced the mean Eczema Area and Severity Index at 4 weeks by 71.5% compared with an increase of 19.4% with vehicle ( P < .001). The reduction in the Eczema Area and Severity Index with pimecrolimus cream 1% was significant at day 4 (38.5% vs 17.6% increase with vehicle). Significant improvements in caregivers' assessments of pruritus and sleep loss were observed with pimecrolimus cream 1% by day 2 ( P < .03) and day 3 ( P = .002), respectively, compared with vehicle. Responses to pimecrolimus cream 1% were sustained during the open-label phase, and pimecrolimus cream 1% was well tolerated. Symptoms of atopic eczema returned gradually after discontinuation. CONCLUSION: Pimecrolimus cream 1% was well tolerated and effective in patients with mild to very severe atopic eczema, with rapid onset of action and no disease rebound after discontinuation.  相似文献   
79.
A recombinant pseudorabies (Aujeszky’s disease) virus (PrV) designated as vE16lac was constructed by deleting a 3-kbp DNA segment spanning the junction of long and short components of the viral genome, and by replacing the deleted segment with a lacZ-expression cassette. The aim of constructing this mutant was (a) to determine whether the terminal repeat (Tr) can serve as a template for the regeneration of the internal repeat (Ir), and (b) whether this deletion causes a reduction in the neuroinvasiveness of the virus. To analyze the mechanism of equalization, revertant viruses were selected and structurally characterized from vE16lac infection of PK-15 cells, mice and pigs. Because all revertants acquired Ir sequences identical to that of the wild-type virus, the equalization process occurred using the Tr as a template to reconstitute the Ir. We also found that the recombinant virus vE16lac was virulent in both pigs and mice. The data are discussed in view of studies performed with similar PrV mutants by other authors (Rall et al., 1992, Dean and Cheung, 1995 and Dean et al., 1996). This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   
80.
A case of ossifying fasciitis occurring in the left femoral region of a 57-year-old male is reported. The patient complained of pain in his left lower extremity which was the site of previous catheterization. During a left femoropopliteal by-pass, a firm and cylindric mass measuring 5 x 3 x 2.5 cm in size was found and extracted from the left groin. Histologically, a reactional lymph node and an irregularly shaped lesion extended into the perinodal fat tissue which is composed of proliferating fibroblasts with occasional mitotic activity. Within this fibroblastic proliferation, immature woven bone composed of osteoid with calcification and chondroid differentiation were seen. Metaplastic bone is an uncommon finding in cases of nodular fasciitis, parosteal fasciitis, cranial fasciitis and florid reactive periostitis. Ossifying fasciitis is known as an uncommon variant of nodular fasciitis. It is an uncommon post-traumatic benign lesion of subcutaneous tissue with an unclear etiology of ossification which is neither related with a bony structure nor contains any muscle tissue. This lesion has been reported only once previously, in the femoral region after a trauma history of catheterization.  相似文献   
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