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101.
Lichen planus of the oral mucosa (OLP) is characterized by lymphocytic infiltrate in the epithelial layer and basal cells lysis. Some studies have suggested a high incidence of oral squamous cell carcinoma in patients with OLP that has been implicated as a premalignant lesion. We describe 19 cases of OLP, and the immunopathologic basis for OLP, its potential association with malignancy and the variable clinical pictures in patients with OLP are reviewed. Also, specific recommendations are given for treatment and follow-up of lesions.  相似文献   
102.
103.
Adenosine is an endogenous antiaggregating substance that influences the platelet responses through specific A-type receptors that activate adenylate cyclase increasing the levels of 3',5'-cyclic adenosine monophosphate (cAMP). In this study, we investigated whether adenosine can also influence the levels of 3',5'-cyclic guanosine monophosphate (cGMP) and decrease the aggregating response of human platelets to adenosine-5-diphosphate (ADP) through this nucleotide. In platelet samples from healthy volunteers, we evaluated the effect of adenosine on ADP-induced aggregation and cyclic nucleotide synthesis. Some experiments were repeated in the presence of dipyridamole (inhibitor of adenosine uptake and phosphodiesterase activity), N(G)-monomethyl-L-arginine (L-NMMA, nitric synthase inhibitor), ionomycin (calcium ionophore), and ambroxol (2-amino-3,5-dibromo-N-[trans-4-hydroxycyclohexyl]benzylamine, inhibitor of nitric oxide (NO)-dependent activation of guanylate cyclase). Adenosine decreased the response to ADP in a concentration-dependent way (analysis of variance, ANOVA: P<.0001): cAMP levels increased from 30.0 +/- 2.0 (control) to 46.0 +/- 3.0 pmol/10(9) platelets (in the presence of 15 mumol/l adenosine) and cGMP levels increased from 5.6 +/- 1.0 (control) to 10.9 +/- 2.0 pmol/10(9) platelets (in the presence of 15 mumol/l adenosine). Also, nucleotide levels measured at the end of aggregation were higher in platelet samples exposed to adenosine than in controls. Dipyridamole at 40 mumol/l slightly increased adenosine's effects on both nucleotides. L-NMMA blunted the effect of adenosine on cGMP both in unstimulated samples and in aggregated platelets without any effect on cAMP synthesis. Platelet exposure to L-NMMA and ambroxol partially prevented adenosine's effect on ADP-induced aggregation. In conclusion, adenosine, which enhances intraplatelet cAMP levels, was determined to also cause an increase in cGMP concentrations through a mechanism that involves NO synthesis. This effect plays a direct role in the adenosine-induced antiaggregation.  相似文献   
104.
Serum cholesterol levels and mood symptoms in the postpartum period   总被引:6,自引:0,他引:6  
During pregnancy, the total serum cholesterol concentration rises up to 43%, followed by a rapid fall after delivery. Mild depressive symptoms ('postpartum blues') are a common complication of the puerperium and affect 30-85% of women in the early postpartum period. Based on these observations, it has been suggested that the sudden fall in cholesterol levels after delivery could serve as a 'natural model' to test the suggested association between cholesterol and mood. The present study was designed to expand the database concerning the association between cholesterol levels and mood in the postpartum period and to address some methodological problems raised by previous studies. Forty-seven healthy primiparous women were interviewed with a structured clinical interview on two occasions: during late pregnancy (median: day -20 before the expected delivery) and during the early postpartum period (median: day 32 after delivery). On both occasions, serum concentrations of total and HDL cholesterol were measured and mood symptoms were assessed with the state form of Spielberger's State-Trait Anxiety Index (STAI), the state form of the State-Trait Anger Scale (STAS), and the Beck Depression Inventory (BDI). We found significant, albeit moderate, relationships between serum cholesterol levels and mood symptoms in the postpartum period that were not present during late pregnancy. Lower postpartum levels of total cholesterol were associated with symptoms of anxiety (r=-0.30, P=0.04), anger/hostility (r=-0.31, P=0.04), and depression (r=-0.35, P=0.02), and lower postpartum levels of HDL cholesterol were associated with symptoms of anxiety (r=-0.34, P=0.02). This study confirms that the physiological fall in blood lipids in the postpartum period can be a useful model to test the relationship between serum cholesterol levels and mood.  相似文献   
105.
106.
Paracetamol is the commonest agent employed in self poisoning, however it is not clear whether adolescents possess insight into the serious complications associated with its misuse. Using a one page questionnaire, the availability, usage, and knowledge of toxicity of paracetamol among 1147 American and British adolescents was assessed. Although 90% of all students recognised that paracetamol could kill, the great majority of students overestimated the lethal dose. In addition, while knowledge regarding side effects of paracetamol was poor the drug was widely available to, and used by, the study population. It is proposed that gross overestimation of the number of tablets required to kill, poor understanding of paracetamol side effects, and wide availability of the drug contribute to its frequent use in adolescent suicidal behaviour. The inclusion of some over-the-counter medications in school drug education programs in addition to tighter control of the availability of paracetamol may help reduce the problem of adolescent self poisoning.  相似文献   
107.
The main purpose of this study was to compare rectal and axillary temperature measurements in African children. Altogether 573 sick children were seen in an outpatient setting in rural West Africa. Rectal and axillary temperatures were measured and the parent or guardian was asked if they thought that the child had a raised body temperature. Normal ranges were defined from an age matched population of 203 healthy children. A raised axillary temperature predicted a raised rectal temperature with a sensitivity of 98% and a specificity of 88%. The parents' impression that their child had a fever was a less sensitive (89%) and less specific (59%) indicator of raised rectal temperature. A raised axillary temperature is a good screening test for a raised rectal temperature in African children.  相似文献   
108.
Doppler and direct measurements of right ventricle to right atrial pressure drop were made during cardiac catheterisation on 28 occasions in 26 infants with congenital heart disease. Age was 10 days to 12 months (median 4.5 months), and weight was 3.1 to 9.0 kg (median 4.7 kg). We measured peak velocity of tricuspid regurgitation by continuous wave Doppler, and the pressure drop was calculated using the modified Bernoulli equation (delta p = 4v2). There was a high correlation (r = 0.95) between direct and Doppler measurements. Doppler values tended to underestimate the right ventricle to right atrial pressure drop, but this was not of clinical significance (mean 2 mm Hg). The 95% confidence interval for the Doppler velocity was -0.41 to +0.26 m/sec, and was consistent across the range of pressures studied. Variability between observers was tested, by two observers performing sequential paired examinations on 16 newborn babies with tricuspid regurgitation. The coefficient of repeatability was 6.3 mm Hg (95% confidence interval 4.7 to 9.5 mm Hg) or 0.26 m/sec (0.18 to 0.50 m/sec). This method of right ventricular pressure estimation, validated previously only in older children and adults, is a reproducible and accurate technique in infants with tricuspid regurgitation.  相似文献   
109.
Previous research has found that patients of osteopathic physicians tend to report poorer general health perceptions than persons in the general population or than patients of allopathic physicians. Quality of life and level of healthcare satisfaction in patients referred to a specialty clinic for osteopathic manipulative treatment (OMT) at a college of osteopathic medicine were measured in 1997. Data from the Medical Outcomes Study 36-Item Short Form (SF-36) were used to compute standardized scores in the following eight health scales: physical functioning, role limitations because of physical problems, bodily pain, general health perceptions, vitality, social functioning, role limitations because of emotional problems, and mental health. There were 185 patients who returned the survey (mean response rate, 90%), including 22 new and 163 established patients. Patients reported poorer health than the general population on all eight scales (P < .001). Patients frequently reported poorer quality of life than referents with hypertension, congestive heart failure, type 2 diabetes mellitus, recent acute myocardial infarction, or clinical depression. More than 97% of established patients were satisfied or very satisfied with the healthcare received at the clinic. This study suggests that referred patients presenting to osteopathic physicians for OMT may have poorer quality of life than is generally recognized when relying only on traditional diagnostic approaches. Early detection and treatment of musculoskeletal conditions may be important factors in preventing chronicity and its impact on quality of life.  相似文献   
110.
Some human tumors express known antigens that can be utilized as targets for specific immunotherapy. An absolute requirement for the efficacy of this therapeutic strategy is an adequate expression of the candidate antigen by all cells of the primary and metastatic tumor. To examine the presence and distribution of tumor-associated antigens in metastatic breast cancer, we used PCR analysis and ethidium bromide staining to test the expression of genes of the MAGE family in 28 primary tumors and related metastatic samples. Overall, samples obtained from 7 of 28 patients revealed positive. However, 2 of 3 primary tumors positive for MAGE-1 and/or MAGE-3 had corresponding negative metastatic lesions. On the contrary, 4 of the 25 MAGE-negative primary tumors gave rise to positive metastatic nodes. Our results confirm in vivo, at the molecular level, the tumor-antigen heterogeneity previously observed at the cellular level by in vitro analysis. Our data strongly suggest that, at least in patients with breast cancer, multiple different antigens would be required to optimize the recognition of neoplastic cells in immunotherapeutic protocols using MAGE products as target antigens. © 1995 Wiley-Liss, Inc.  相似文献   
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