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61.
Oral Diseases (2012) 19 , 85–91 Objective: To analyze the expression and distribution patterns of mature dendritic cells (mDCs) and immature DCs (imDCs) in radicular cysts (RCs), dentigerous cysts (DtCs), and keratocystic odontogenic tumors (KCOTs). Materials and methods: Forty‐nine odontogenic cystic lesions (OCLs) (RCs, n = 20; DtCs, n = 15; KCOTs, n = 14) were assessed using the following markers: S100, CD1a and CD207 for imDCs; and CD83 for mDCs. Results: Almost all cases were S100, CD1a, and CD207 positive, whereas 63% were CD83 positive. RCs presented greater number of immunostained cells, followed by DtCs, and KCOTs. The number of S100+ cells was greater than both CD1a+ and CD207+ cells (P < 0.001), which showed approximately similar amounts, followed by lower number of CD83+ cells (P < 0.001) in each OCL type. Different from S100+ cells, both CD1a+ and CD207+ cells on the epithelium (P < 0.05) and CD83+ cells on the capsule (P < 0.05) were preferentially observed. In RCs, significant correlation was found between the thickness epithelium with S100+ and CD1a+ cells, and between the degree of inflammation with CD83+ cells. Conclusions: Dendritic cell populations in OCLs can be phenotypically heterogeneous, and it could represent distinct lineages and/or functional stages. It is suggested that besides DC‐mediated immune cell interactions, DC‐mediated tissue differentiation and maintenance in OCLs should also be considered.  相似文献   
62.
BACKGROUND: Intravenously administered perfluorocarbon (PFC) emulsions increase oxygen solubility in plasma. PFC might therefore temporarily replace red cells (RBCs) lost during intraoperative hemorrhage. In patients who have undergone hemodilution, the return of autologous blood may be delayed by the administration of PFC, and autologous RBCs may be saved for transfusion after surgical bleeding is stopped and PFC is cleared by the reticuloendothelial system. STUDY DESIGN AND METHODS: In 22 anesthetized, hemodiluted dogs (hemoglobin [Hb] 7 g/dL) breathing 100-percent O2, an intraoperative volume-compensated blood loss was simulated. The efficacy of three therapeutic regimens in maintaining tissue oxygenation was compared: 1) RBC group (n = 7): maintenance of a Hb > 7 g per dL by transfusion of autologous RBCs; 2) PFC group (n = 7): bolus application of a second-generation PFC emulsion (60% wt/vol perflubron) and further acute normovolemic hemodilution (ANH) to a Hb of 3 g per dL; and 3) control group (n = 7): further ANH alone to a Hb of 3 g per dL. Systemic and myocardial oxygenation status and tissue oxygenation were assessed. RESULTS: Autologous RBCs transfused to maintain a Hb of 7 g per dL preserved hemodynamics and tissue oxygenation during blood loss. In the PFC and control groups, heart rate and cardiac index increased significantly in response to further ANH. Tissue oxygenation was not different in the PFC and the RBC groups. Direct comparison of the PFC and control groups revealed better tissue oxygenation in the PFC group, as reflected by significantly higher mixed venous, coronary venous, and local tissue pO2 on liver and skeletal muscle. CONCLUSION: Bolus intravenous administration of 60- percent (wt/vol) perflubron emulsion and further hemodilution from a Hb of 7 g per dL to one of 3 g per dL were as effective as autologous RBC transfusion in maintaining tissue oxygenation during volume-compensated blood loss designed to mimic surgical bleeding.  相似文献   
63.
OBJECTIVE: The hypothalamic-pituitary-adrenal (HPA) axis has been proposed to be susceptible to fetal programming, the process by which an adverse fetal environment elicits permanent physiological and metabolic alterations predisposing to disease in later life. It is hypothesized that fetal exposure to poor circumstances alters the set point of the HPA axis, leading to increased HPA axis activity and subsequent increased cortisol concentrations. In this study, we tested the hypothesis that prenatal exposure to famine during different periods of gestation is associated with increased activity of the HPA axis. DESIGN AND METHODS: We assessed plasma cortisol concentrations after a dexamethasone suppression and an ACTH1-24 -stimulation test in a group of 98 men and women randomly sampled from the Dutch famine birth cohort. Cohort members were born as term singletons around the 1944-1945 Dutch famine. RESULTS: Cortisol profiles after dexamethasone suppression and ACTH1-24 stimulation were similar for participants exposed to famine during late, mid- or early gestation (P = 0.78). Cortisol concentrations after dexamethasone suppression test did not differ between those exposed and those unexposed to famine in utero (mean difference -2% (95% confidence interval (CI) -27 to 23)). Neither peak cortisol concentration (20 nmol/l (95% CI -27 to 66)), cortisol increment (-5 nmol/l (95% CI -56 to 47)) or cortisol area under the curve post-ACTH1-24 injection (4% (95% CI -4 to 12)) differed between exposed and unexposed participants. CONCLUSIONS: Prenatal famine exposure does not seem to affect HPA axis activity at adult age, at least not at the adrenal level. This does not exclude altered HPA axis activity at the levels of the hippocampus and hypothalamus.  相似文献   
64.
An eclamptic seizure occurring at 32+2 weeks of gestation was treated with magnesium sulfate. Accidentally an overdose was given. As a consequence, the patient had a cardiopulmonary arrest. Immediate resuscitation and calcium gluconate administration did restore vital functions. Pregnancy continued for 4 weeks after the accident. Both mother and child left the hospital in good condition.  相似文献   
65.
Abstract: Background : A home confinement with midwifery care is still an integral part of Dutch maternity care. It has been argued that the existence of home birth itself influences the course of the birth process positively, which is why obstetric interventions are low in comparison with neighboring countries. This study examined the impact of women's intended place of birth (home or hospital) and the course of pregnancy and labor when attended by midwives. Methods : This is a prospective study of 625 low‐risk pregnant women, gestation 20 to 24 weeks, enrolled in 25 independently working midwifery practices. The course of labor was measured by the frequency of interventions by midwives and obstetricians. Results : A more nontechnological approach to childbirth was observed within the women opting for a home birth compared with the women opting for a hospital birth. Data showed a relationship between interventions and planned birth site: sweeping membranes and amniotomy by midwives were more likely to be conducted in women opting for a home birth. Multiparas opting for hospital birth were more likely to experience consultations and referrals. Within the group of multiparas referred for obstetrician care, women intending to have a home birth experienced fewer interventions (e.g., induction, augmentation, pharmacologic pain relief, assisted delivery, cesarean section) compared with those who had opted for a hospital birth. Conclusions : A large proportion of women desire a home birth. The impact of that choice demonstrated a smoother course of the birth process, compared with women who desired to deliver in the hospital, as measured by fewer obstetric interventions. We suggest that psychological factors (expectation and perceptions) influence both a woman's decision of birthplace and the actual birth process. (BIRTH 31:1 March 2004)  相似文献   
66.
OBJECTIVE: The purpose of this study was to investigate whether the altered vascular resistance in pregnancy and preeclampsia results from alterations in intrinsic vascular smooth muscle properties or from external influences on vascular smooth muscle function. STUDY DESIGN: We studied subcutaneous resistance arteries from women with preeclampsia, from normal pregnant women, and from nonpregnant women, that were obtained during cesarean delivery or gynecologic surgical procedures, in a pressure myograph. Arteries were denervated, and smooth muscle cells were loaded with calcium indicator fura-2. Contractile properties were tested in physiologic saline solution and during potassium- and norepinephrine-induced constriction at various pressures. In addition, endothelial function was assessed. Intracellular calcium and tone were measured continuously. RESULTS: No significant differences in basal tone, constrictor, and myogenic responses were found between groups. Contractile element calcium sensitivity was significantly increased in women with preeclampsia. Norepinephrine caused an increase in calcium sensitivity in all groups. CONCLUSION: Vascular smooth muscle calcium sensitivity is increased in preeclampsia.  相似文献   
67.
The deep mycoses are uncommon infections, usually acquired from the inhalation or ingestion of fungal spores, sometimes from the soil in areas of endemicity, such as in the Americas and south-east Asia, or from decaying vegetable matter. They are also seen in immunocompromised persons and, increasingly, in HIV-infected persons. Respiratory involvement is frequent, with granuloma formation, and mucocutaneous involvement may be seen. Oral lesions of the deep mycoses are typically chronic but non-specific, though nodular or ulcerative appearances are common. Person-to-person transmission is rare. In HIV disease, the most common orofacial involvement of deep mycoses has been in histoplasmosis, cryptococcosis, aspergillosis and zygomycosis. Diagnosis is usually confirmed by lesional biopsy although culture may also be valuable. Treatment is with amphotericin or an azole.  相似文献   
68.
From 1560 twin pregnancies the birthweights were considered in relation to menstrual age. Compared to singletons a retardation of growth from about the 33rd wk of pregnancy was found. 407 measurements of the fetal biparietal diameter were performed in 69 twin pregnancies. Compared to singletons a retardation of growth of the fetal biparietal diameter was found from about the 30th wk of pregnancy. The suggestion is made that in singletons the birthweight values of prematurely born children are below fetal weight values at the same duration of pregnancy of children who will be born at term.  相似文献   
69.
Background: Thalassaemia and other structural haemoglobinopathies are the major genetic disorders prevalent in certain parts of the world including India. This study presents the pattern of haemoglobinopathies amongst the referred patients of anaemia in a two-year period.  相似文献   
70.
The prevalence ofChlamydia trachomatis infection in a population of women with no symptoms of sexually transmitted disease was investigated. These women, aged 35–55 years, participated in a screening program for cervical cancer. With the use of a direct immunofluorescence method, 109 out of 2,470 smears tested were positive forChlamydia trachomatis, indicating an overall prevalence of 4.4%. No changes in prevalence were found when five-year cohorts of this group were analyzed, indicating that age-dependent changes or epidemiological factors do not result in a different (decreased) prevalence over the ages 35 to 55 years. The prevalence ofTrichomonas vaginalis and fungi, as detected by cytological screening, was lower than that observed forChlamydia trachomatis: 3.1 and 2.1%, respectively. Of the 109 smears positive forChlamydia trachomatis, 90 showed cervical cells with reactive changes (out of 1,490 smears with PAP II), whereas no cytological changes were found in 15 cases (out of 884 smears with PAP I). Changes suggestive of mild or moderate dysplasia were found in only four cases (out of 93 smears with PAP III). The results indicate thatChlamydia trachomatis is associated with reactive changes of endocervical cells and raise serious questions about whether prevention of possible secondary effects such as infertility and pelvic inflammatory disease can be achieved by a combined screening program for cervical cancer andChlamydia trachomatis.  相似文献   
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