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11.
The pleural space is a virtual compartment between the lung and chest wall that becomes filled with fluid and inflammatory cells during a variety of respiratory diseases. Here, we study the potential role of the eicosanoid metabolite leukotriene B4 (LTB4) in disparate diseases leading to acute (pneumonia) or chronic (tuberculosis, cancer) inflammation of the pleural space. LTB4 concentrations were significantly higher in pleural fluid due to pneumonia, tuberculosis and cancer with respect to congestive heart failure and correlated with neutrophil elastase, which is used as an indication of state of activation of neutrophils in the pleural space. Moreover, pleural LTB4 was biologically active, as an anti-LTB4 antibody partially neutralized the chemotactic activity of parapneumonic, tuberculous and cancer effusions. Macrophages, neutrophils, lymphocytes, mesothelial cells and cancer cells all expressed mRNA for 5-lipoxygenase, the enzyme that initiates leukotriene synthesis leading to the production of LTB4, in exudative pleural effusions. Upon stimulation in transudative pleural effusions, pleural macrophages produced, in a time-dependent fashion, a significantly higher concentration of LTB4 than mesothelial cells. These studies demonstrate that different cell types are capable of producing LTB4 in the inflamed pleural space and that this mediator may play a crucial role in the recruitment of neutrophils into the pleural space.  相似文献   
12.
This review describes the usefulness of colour Doppler energy (CDE) (or power Doppler) imaging to measure vascularization in the female reproductive tract. CDE imaging is characterized by an increased sensitivity to flow, and thus may be useful in low-flow states and when optimal Doppler angles cannot be obtained. In addition, longer segments of vessels and more individual vessels can be visualized with CDE imaging. The role of CDE imaging in the evaluation of stromal vasculature in normal and in polycystic ovaries is described, and the relationship between follicular vascularity and outcome following in-vitro fertilization are discussed, together with the findings obtained from the evaluation of thecal arteriole of corpus luteum in early pregnancy. The fundamental role of CDE imaging in differentiation among ovarian masses is also reviewed. We summarize the role of CDE imaging in pregnancy, and describe two new applications of three-dimensional power Doppler sonography and the use of ultrasound contrast media. In conclusion, CDE imaging can replace conventional colour Doppler when the information on the direction of flow is not useful. Moreover, the technique appears superior to others for describing microvascular architecture and determining the presence or absence of flow.  相似文献   
13.
In male rats, noncontact erections occur concomitantly with an increase in NO2- and NO3- in the paraventricular nucleus of the hypothalamus (PVN). In the present study, both responses were reduced by the blockade of PVN excitatory amino acid receptors by dizocilpine, (+)-MK-801(1 and 5 microg), but not by 6-cyano-7-nitro-quinoxaline-2,3-dione (5 microg) or (+)-2-amino-4-phosphono-butanoic acid (5 microg). Also ineffective when injected into the PVN were the dopamine antagonists SCH 23390 (5 microg), S(+)-raclopride (10 microg), and cis-flupenthixol (10 microg), and the oxytocin antagonist d(CH2)5Tyr(Me)2-Om8-vasotocin (1 microg). However, when the last was given into the lateral ventricles, it reduced noncontact erections without modifying NO2- and NO3- increases. These results suggest that excitatory amino acid transmission increases in the PVN during noncontact erections. This may contribute to increased NO production in the PVN, and it may activate oxytocin neurons mediating this sexual response.  相似文献   
14.
The majority of Duchenne muscular dystrophy (DMD) female carriers show dystrophin immunostaining abnormalities, although a significant proportion of clinically non-manifesting carriers are normal following this analysis. We had the opportunity to study dystrophin immunostaining in two different muscles, the vastus lateralis and the rectus abdominis of a possible DMD carrier. While the vastus showed normal dystrophin immunostaining, pathological staining was detected in her rectus abdominis. These findings seem to indicate that dystrophin expression can vary in different muscle groups of a DMD carrier. The implications of these findings in DMD carrier detection and possible dystrophin function are discussed.  相似文献   
15.
A reversed-phase high-performance liquid chromatography (HPLC) method with diode-array detection for the quantification of several human salivary peptides is described. Sample pretreatment consisted of the acidification of whole saliva by phosphate buffer. This treatment produced precipitation of mucins, alpha-amylases and other high-molecular-mass salivary proteins, simultaneous inhibition of intrinsic protease activities and reduction of sample viscosity. Direct HPLC analysis by diode-array detection of the resulting acidic sample allowed one to quantify histatin 1, histatin 3, histatin 5, statherin, as well as uric acid, in normal subjects. Moreover, the groups of peaks pertaining to proline-rich proteins and cystatins were tentatively identified. The method can be useful in assessing the concentration of salivary peptides from normal subjects and from patients suffering oral and/or periodontal diseases.  相似文献   
16.
To evaluate the effectiveness of the oxidized regenerated celluloseabsorbable barrier (Interceed®, TC7) in the prevention ofde-novo adhesion formation after laparoscopic myomectomy, aprospective and randomized study was performed at the Departmentof Obstetrics and Gynaecology of the University of Cagliari,Cagliari, Italy. A total of 50 pre-menopausal non-pregnant women,aged 23—42 years, who submitted to laparoscopic myomectomyfrom January 1993 to June 1994, were randomized to surgery alone(control group, n = 25) or surgery and oxidized regeneratedcellulose barrier (Interceed group, n = 25). Neither group receivedany other treatment for adhesion prevention. A second-look laparoscopywas performed 12—14 weeks after laparoscopic myomectomy.The incidence of adhesion-free patients was assessed at second-looklaparoscopy by an investigator not informed of the treatment.The numbers of adhesion-free patients were three out of 25 (12%)in the control group and 15 out of 25 (60%) in the treatmentgroup (P < 0.05). In conclusion, the oxidized regeneratedcellulose absorbable barrier significantly reduced de-novo adhesionformation after laparoscopic myomectomy.  相似文献   
17.
18.
OBJECTIVE: To evaluate the short- and long-term effect on the uterus, endometrium, and vascular reactivity of uterine arteries of sequential transdermal estradiol (50 microg/day) and norethisterone (0.25 mg/day in the last 14 days of each cycle). DESIGN: An intravaginal ultrasound evaluation was performed in 48 postmenopausal women before and at the 3rd and 12th month of treatment, during the last 3 days of both estradiol alone and estradiol plus norethisterone. An endometrial biopsy was also performed before and at the end of treatment. In 11 participants, intravaginal ultrasound and endometrial biopsy were repeated after 48 months of treatment. RESULTS: Uterine volume (33.7 +/- 3.3 cm3 to 56.8 +/- 3.7 cm3; p = 0.001) and endometrial thickness (3.07 +/- 0.48 mm to 5.74 +/- 0.41 mm; p = 0.001) increased within 3 months, with no further increases. Thickness was similar in the estradiol and estradiol-norethisterone phase. Endometrial hyperplasia was found in one participant at 12 months of treatment. A significant decrease (p = 0.002) in the pulsatility index of uterine arteries was observed only during the estradiol phase. After 48 months of treatment, the pulsatility index of uterine arteries was lower than at baseline (2.78 +/- 0.24 vs. 2.23 +/- 0.33; p = 0.044) even when evaluated in the combined phase. CONCLUSIONS: The transdermal administration of sequential estradiol and norethisterone reduces uterine artery resistance and induces a self-limiting growth of the uterus and endometrium.  相似文献   
19.
Tissue factor (TF) is an integral membrane protein that binds factor VIIa and initiates coagulation. The extracellular domain of TF is responsible for its hemostatic function and by implication in the dysregulation of coagulation, which contributes to death in endotoxemia. The role of the cytoplasmic domain of tissue factor in endotoxemia was studied in mice, which lack the cytoplasmic domain of TF (TF(deltaCT/deltaCT)). These mice develop normally and have normal coagulant function. Following i.p injection with 0.5 mg of lipopolysaccharide (LPS), TF(deltaCT/deltaCT) mice showed significantly greater survival at 24 hours compared to the wt mice (TF(+/+)). The serum levels of TNF-alpha and IL-1beta were significantly lower at 1 hour after LPS injection and IL-6 levels were significantly lower at 24 hours in TF(deltaCT/deltaCT) mice compared to TF(+/+)mice. Neutrophil recruitment into the lung was also significantly reduced in TF(deltaCT/deltaCT) mice. Nuclear extracts from tissues of endotoxemic TF(deltaCT/deltaCT) mice also showed reduced NFkappaB activation. LPS induced leukocyte rolling, adhesion, and transmigration in post-capillary venules assessed by intravital microscopy was also significantly reduced in TF(deltaCT/deltaCT) mice. These results indicate that deletion of the cytoplasmic domain of TF impairs the recruitment and activation of leukocytes and increases survival following endotoxin challenge.  相似文献   
20.
The effect of muscimol and baclofen injected into the paraventricular nucleus of the hypothalamus on penile erection and yawning induced by apomorphine, oxytocin and N-methyl-D-aspartic acid (NMDA) was studied in male rats. Muscimol (20-200 ng), but not baclofen (200 ng), injected into the paraventricular nucleus of the hypothalamus 10 min before apomorphine (50 ng), oxytocin (10 ng) or NMDA (50 ng) reduced penile erection and yawning induced by the above compounds given into the paraventricular nucleus. Bicuculline (250 ng) injected into the paraventricular nucleus 5 min before muscimol (100 ng) prevented the inhibitory effect of muscimol on penile erection and yawning induced by apomorphine, oxytocin and NMDA. The present results show that gamma-aminobutyric acid (GABA) inhibits penile erection and yawning by acting on GABA(A) receptors in the paraventricular nucleus of the hypothalamus.  相似文献   
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