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101.
The dysplastic nevus in nonfamilial melanoma is a clinicopathologic entity consistently demonstrating an eightfold or greater association with malignant melanoma. The present report quantifies the relationship between nuclear atypia and 16 architectural and cytoplasmic features in 153 pigmented nevi removed from a similar number of patients with newly diagnosed nonfamilial melanoma. All lesions were evaluated by one dermatopathologist, and most lesions were reviewed by a second dermatopathologist. Nuclear atypia of nevomelanocytes was defined as at least three of the following: nuclear enlargement, pleomorphism, hyperchromatism, and prominent nucleoli easily observed throughout each lesion. Seventeen percent of the total nevi had such atypia. On univariate analysis, 11 parameters (lentiginous hyperplasia of the epidermis, basal melanocytic hyperplasia, junctional nest disarray, fusion [bridging] of theques, suprabasal melanocytes, lymphoid response, prominent vascularity, fibroplasia, abundant cytoplasm, "dusty" cytoplasm, and large melanin granules) showed an association with nuclear atypia (P less than .05). However, on multivariate analysis only five parameters continued to be important: basal melanocytic hyperplasia, junctional nest disarray, melanophages (inverse correlation), prominent vascularity, and large melanin granules. These data support the idea that multiple histopathologic characteristics, correlating objectively with nuclear atypia, are important for the diagnosis of dysplastic nevi. In our view, the minimal essential histologic criteria for dysplastic nevi based on these findings include nuclear atypia and abnormal patterns of intraepidermal nevomelanocytic proliferation (ie, basal melanocytic hyperplasia and/or junctional nest disarray).  相似文献   
102.
Previous studies have demonstrated that the urinary bladder is a consistent source for isolating the Lyme disease spirochete, Borrelia burgdorferi, from both experimentally infected and naturally exposed rodents. We examined histopathologic changes in the urinary bladder of different types of rodents experimentally infected with Lyme spirochetes, including BALB/c mice (Mus musculus), nude mice (M. musculus), white-footed mice (Peromyscus leucopus), and grasshopper mice (Onychomys leucogaster). Animals were inoculated intraperitoneally, subcutaneously, or intranasally with low-passaged spirochetes, high-passaged spirochetes, or phosphate-buffered saline. At various times after inoculation, animals were killed and approximately one-half of each urinary bladder and kidney were cultured separately in BSK-II medium while the other half of each organ was prepared for histologic examination. Spirochetes were cultured from the urinary bladder of all 35 mice inoculated with low-passaged spirochetes while we were unable to isolate spirochetes from any kidneys of the same mice. The pathologic changes observed most frequently in the urinary bladder of the infected mice were the presence of lymphoid aggregates, vascular changes, including an increase in the number of vessels and thickening of the vessel walls, and perivascular infiltrates. Our results demonstrate that nearly all individuals (93%) of the four types of mice examined had a cystitis associated with spirochetal infection.  相似文献   
103.
The aim of this study was to investigate the predictive and prognostic value of PLR, and the relationship between PLR and tumor localization.A total of 229 patients with de-novo metastatic CRC were retrospectively analyzed. The cutoff value for PLR was defined by the receiver operating characteristic (ROC) curve analysis and threshold value of 196.5 as best cut-off value was found.The higher rate of BRAF mutation was significantly detected for patients with PLRhigh (> 196.5) compared to those with PLRlow (≤196.5) (P = .001). PLR was significantly higher in tumors located on the right colon (P = .012). PLR, tumor localization, the presence of surgery for primary tumor, the presence of curative surgery, the presence of metastasectomy for progression-free survival (PFS) and PLR, gender, BRAF mutation, tumor localization, the presence of surgery for primary tumor, the presence of metastasectomy for overall survival (OS) were found to be prognostic factors by univariate analysis. Multivariate analysis showed that PLR, the presence of curative surgery and the presence of metastasectomy for both PFS and OS were found to be independent prognostic factors. Moreover, a logistic regression analysis indicated that PLR and tumor localization were found to be an independent factors for predicting response to systemic treatment (P < .001 and P = .023 respectively).Our results showed that pretreatment PLR was readily feasible and simple biomarker predicting response to treatment and survival, in addition it was significantly associated with tumor localization.  相似文献   
104.
Using monoclonal antibodies to spirochetal antigens and lymphoid cell surface markers, we examined the synovial lesions of 12 patients with Lyme disease, and compared them with rheumatoid synovium and tonsillar lymphoid tissue. The synovial lesions of Lyme disease patients and rheumatoid arthritis patients were similar and often consisted of the elements found in normal organized lymphoid tissue. In both diseases, T cells, predominantly of the helper/inducer subset, were distributed diffusely in subsynovial lining areas, often with nodular aggregates of tightly intermixed T and B cells. IgD-bearing B cells were scattered within the aggregates, and a few follicular dendritic cells and activated germinal center B cells were sometimes present. Outside the aggregates, many plasma cells, high endothelial venules, scattered macrophages, and a few dendritic macrophages were found. HLA–DR and DQ expression was intense throughout the lesions. In 6 of the 12 patients with Lyme arthritis, but in none of those with rheumatoid arthritis, a few spirochetes and globular antigen deposits were seen in and around blood vessels in areas of lymphocytic infiltration. Thus, in Lyme arthritis, a small number of spirochetes are probably the antigenic stimulus for chronic synovial inflammation.  相似文献   
105.
Femoral hypoplasia-unusual facies syndrome comprises malformations of the skeletal system consisting of shortened or absent bilateral femurs, variable bony sacral abnormalities, bilateral talipes equinovarus, and an unusual facies consisting of low-set ears with soft cartilage of the helix, up-slanting palpebral fissures, shortened nose, blunt alae nasi, elongated philtrum, and a thin upper lip. Inferiorly placed kidneys and a septated urinary bladder have also been reported, along with cardiovascular and gastrointestinal abnormalities such as esophageal reflux. The cause and pathogenesis are believed to be multifactorial and probably not inherited. We report the case of a newborn infant with visceral abnormalities not previously recognized in this complex: polysplenia, superiorly placed adrenals at the muscular diaphragms, a single pelvic kidney located in the uterosacral ligament, and anorectal agenesis with the colon ending in a blind pouch above the uterus.  相似文献   
106.
AIMS: The Brugada criteria proposed to distinguish between regular, monomorphic wide QRS complex tachycardias (WCT) caused by supraventricular (SVT) and ventricular tachycardia (VT) have been reported to have a better sensitivity and specificity than the traditional criteria. By incorporating two new criteria, a new, simplified algorithm was devised and compared with the Brugada criteria. METHODS AND RESULTS: A total of 453 WCTs (331 VTs, 105 SVTs, 17 pre-excited tachycardias) from 287 consecutive patients with a proven electrophysiological (EP) diagnosis were prospectively analysed by two of the authors blinded to the EP diagnosis. The following criteria were analysed: (i) presence of AV dissociation; (ii) presence of an initial R wave in lead aVR; (iii) whether the morphology of the WCT correspond to bundle branch or fascicular block; (iv) estimation of initial (v(i)) and terminal (v(t)) ventricular activation velocity ratio (v(i)/v(t)) by measuring the voltage change on the ECG tracing during the initial 40 ms (v(i)) and the terminal 40 ms (v(t)) of the same bi- or multiphasic QRS complex. A v(i)/v(t) >1 was suggestive of SVT and a v(i)/v(t) 相似文献   
107.
OBJECTIVE: To determine if clinically asymptomatic knee joints in patients with recent onset arthritis reveal histological evidence of synovitis. METHODS: As part of a prospective study of patients with synovitis of less than one year duration, we performed blind needle biopsies on the knees of 20 patients who had synovitis elsewhere but no symptoms or detectable swelling or tenderness of the biopsied joint. RESULTS: Histologic evidence of synovitis was observed in 11 knees (55%). All patients with synovitis had evidence of synovial lining cell hyperplasia, increased vascularity, and lymphocytic infiltrates. Five of 6 patients with rheumatoid arthritis (RA) and 5 of 8 with undifferentiated arthritis had histological evidence of synovitis, but none of the 5 with reactive arthritis (ReA) had synovitis in the asymptomatic joints. Histologic evidence of synovitis persisted in some after clinical resolution of previous pain and swelling, while it occurred in others with no history of previous involvement of that knee. CONCLUSION: Even asymptomatic joints in patients with RA and undifferentiated arthritis of recent onset reveal histologic signs of synovitis. The earliest changes may occur before symptoms. Histologic changes also persist after resolution of previous early symptoms. Evidence of inflammation was not present in asymptomatic joints in our 5 patients diagnosed with ReA.  相似文献   
108.
109.
Aydin S  Seker E 《Die Pharmazie》2005,60(2):147-150
The aqueous distillate of Origanum onites L. (Labiatae) was reported to have various ethnomedical uses including effects on the gastrointestinal tract. The effects of three different doses (0.1, 0.2 and 0.4 mL) of the aqueous distillate of Origanum onites on isolated rat fundus, duodenum and ileum against acetylcholine induced contractions were investigated in this study. The aqueous distillate inhibited contractions in a dose dependent manner. Inhibitions were lowest on fundus. Carvacrol, being the major compound of the test substance, did not inhibit acetylcholine induced contractions of the isolated rat fundus, indicating the presence of other active principles including menthane diols. As being one of the first pharmacological studies on aqueous distillates, a possible pharmacological activity of cis-p-menth-4-ene-1,2-diol and 3,7-dimethyl-1-octen-3,7-diol is proposed in this study.  相似文献   
110.
BACKGROUND: Body surface potential mapping has been shown to be a useful tool in the diagnosis and localization of remote non-Q wave and Q wave myocardial infarction, but human expertise is required to interpret the maps. OBJECTIVE: To identify quantitative body surface potential mapping parameters that could enable a computer-based diagnosis. METHODS: Body surface isopotential maps (63 unipolar leads) were recorded in 86 patients with remote Q wave and 71 patients with remote non-Q wave myocardial infarction. Twenty-four healthy adults served as control subjects. Myocardial infarctions were classified using standard electrocardiogram leads in the acute and chronic phases, and were validated by coronary angiography, ventriculography and thallium scintigraphy. RESULTS: Two simple quantitative parameters with high diagnostic power were identified: the time interval between the peak minimum and the peak maximum potentials (time-shift), and the ratio of these potentials (maximum to minimum ratio [max/min]). Both parameters showed significant differences between infarction patients and normal control subjects, and optimum cut-off values were determined using receiver operating characteristic curves (anterior infarction: time-shift of -4 ms or less, max/min of 0.6 or less; posterior infarction: time-shift of 8 ms or greater, max/min of 1.25 or greater). The sensitivities of the two parameters were 100% and 97%, and the specificities were 99% and 100%, respectively, in the anterior Q wave infarction group, compared with sensitivities of 88% and 100%, and specificities of 94% and 95%, respectively, in the posterior Q wave infarction group. In the anterior non-Q wave infarction group, sensitivity was 35% for both parameters, specificity was 100% for both parameters, and only infarctions associated with a low ejection fraction were detected, indicating that infarction size may influence the power of the tests. CONCLUSIONS: Time-shift and max/min are two new, simple, powerful parameters for infarction diagnosis and may also be suitable for automated, computer-based processing.  相似文献   
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