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91.
The diagnosis of lesions associated with human papillomavirus infection can be difficult because the results of the tests used can be contradictory. Our goal was to compare some of these tests and to evaluate their comparative strengths and weaknesses as clinically useful tools in confirming the diagnosis, especially in borderline cases. Twenty-one consecutive patients from our colposcopy clinic were screened with cytology and colposcopy. Biopsies were taken from representative areas on the cervix and vulva and divided. One-half was evaluated with Southern blot hybridization and the other half with histology and with RNA and DNA in situ hybridization. Cytology and histology were interpreted as either "positive" (showing definite evidence of human papillomavirus infection or cervical intraepithelial neoplasia [CIN]), "negative" (showing no evidence of human papillomavirus infection or CIN) or "equivocal" (atypical [class II] Papanicolaou smears or histology suggestive but not diagnostic of condyloma). In order to determine the clinical significance of equivocal results the sensitivity and specificity of these tests were calculated, with the equivocal results reclassified as either positive or negative. Colposcopy was the most sensitive technique but was not very specific. Cytology was a very sensitive screening tool when the atypical (class II) smears were considered positive but not when they were considered negative. The specificity of the histologic diagnosis was doubled with the equivocal results considered negative when compared to the specificity of the histologic diagnosis with the equivocal results considered positive, with no loss of sensitivity. Each technique has drawbacks, and therefore no one should be used to diagnose and treat these lesions to the exclusion of all others.  相似文献   
92.
Over a 10-year period when 51,022 singleton infants were delivered, 19 pregnancies (1 in 2,685) were complicated by acute polyhydramnios 17 (1 in 3,000) by subacute polyhydramnios and 501 (1 in 102) by chronic polyhydramnios. The incidence of major congenital malformations in singleton pregnancies associated with acute polyhydramnios was 63% and the perinatal mortality rate was 74%. When subacute polyhydramnios occurred in singleton pregnancies, the incidence of major congenital malformations was 65%, similar to acute polyhydramnios, but the perinatal mortality rate was only 35%. The comparable figures for chronic polyhydramnios in singleton pregnancies were a major malformation incidence of 14% and perinatal mortality rate of 10%. The type of onset of polyhydramnios, acute, subacute or chronic is therefore the most important indicator of prognosis. In patients with gross polyhydramnios, acute renal failure must be specifically excluded.  相似文献   
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 The expression of the pyruvate kinase (PK) isoenzymes L and M2 was analysed in the livers of rats treated with the hepatocarcinogenic agent N-nitrosomorpholine (NNM) in the drinking water. In control animals L-PK expression was restricted to liver parenchymal cells, whereas M2-PK was detected in bile duct epithelial, blood vessel wall, endothelial and Kupffer cells. In rats treated with NNM proliferating oval cells were consistently L-PK negative and M2-PK positive, while the ductal cells of cholangiofibroses were clearly L-PK positive and coexpressed M2-PK. However, no morphological differentiation of ductal cells into hepatocyte-like cells was observed. In the clear and acidophilic cell foci storing glycogen in excess strong staining for L-PK was observed. In glycogen-poor foci induced by NNM a shift from L-PK to M2-PK expression takes place. Received: 24 March 1998 / Accepted: 13 November 1998  相似文献   
96.
Human papillomaviruses (HPVs) cause benign papillomas and squamous cell carcinomas in the genital and respiratory tracts. Recurrent respiratory papillomas (RRP) generate a high level of morbidity and significant mortality because of their location, resistance to treatment, and relentless recurrence that can vary in frequency in a given patient and between patients. We have found that T-cells from these patients, when exposed to or isolated from autologous papilloma tissue, have an elevated percentage of CD8(+), CD28(-) T-cells, and that T-cells from many of these patients express an increase in T(H)2-like cytokine mRNA in response to autologous papilloma tissue. Furthermore, both of these immunologic findings correlate with disease severity. These observations suggest that patients with RRP, and possibly others with refractory HPV-induced lesions, are unable to manage their disease with an appropriate and effective HPV-specific, T-cell response. This immune imbalance may be responsible for the development and severity of HPV-induced respiratory papillomatosis.  相似文献   
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Chlorhexidine (CHX) and Hydrogen peroxide (HP) are potent antibacterial agents that are used in controlling dental plaque. However, both agents bear undesired side-effects. We have tested the hypothesis that an antibacterial synergistic effect can occur between the two agents against Streptococcus sobrinus, Streptococcus faecalis and Staphylococcus aureus. We have found that at several combinations of HP and CHX an antibacterial synergistic effect does occur, while at other combinations a on-significant synergism was noticed. No antagonism between the two agents was found in our experimental system. It can be postulated that the mechanism of this synergistic effect is via alteration of the bacterial cell-surface by CHX thereby allowing for an increased amount of HP to penetrate and to react with the intercellular organelles of the bacteria. These results suggest that CHX and HP can be of use in controlling the dental plaque in the oral cavity.  相似文献   
99.
Relatively little data exist concerning the utility of brief cognitive measures to detect dementia among African Americans. The current study evaluated the clinical utility of the Mini-Mental Status Exam (MMSE) and the Fuld Object Memory Evaluation (FOME) in detecting Alzheimer's disease (AD) among both African American and European American older adults. One hundred and forty geriatric patients from a large urban academic medical center were examined. Overall, the FOME appeared to be more effective in detecting AD than was the MMSE (93% sensitivity vs. 75% sensitivity, respectively), although both measures suffered from relatively low specificity (63.5) in the full sample. The FOME demonstrated exceptional clinical utility among African American patients (sensitivity 98.3%; specificity = 64.5; positive predictive power 83.8%; negative predictive power 95.2%). The results of this study support the use of the FOME among older African Americans to detect dementia.  相似文献   
100.
The cutaneous microcirculation shows a significant heterogeneity. With high-resolution two-dimensional laser Doppler perfusion imaging (LDPI), spatial and temporal reproducible perfusion measurements can be reached. The objective of this study was the quantification of skin perfusion in 20 defined skin areas with LDPI, in 60 healthy young and old volunteers. The perfusion of the face was significantly higher than that of the trunk and extremities. The highest perfusion values were seen at the lips, 1.47 arbitrary units (AU), followed by the chin (0.99 AU), the nose (0.95 AU), the forehead (0.73 AU) and the cheek (0.72 AU). Mean perfusion, between 0.40 and 0.49 AU, was seen at the extremities and at the trunk. The lowest perfusion was found at the bottom (0.37 AU), on the back of the foot (0.36 AU) and on the soles (0.31 AU). There was a tendency to show higher perfusion values in men than in women (0.60 +/- 0.31 vs. 0.53 +/- 0.26 AU). Age-related differences in perfusion could not be demonstrated. In the evaluation of the perfusion of pathological skin, regional perfusion differences must be considered, whereas moderate age or gender differences between different investigation groups can be tolerated.  相似文献   
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