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1.
ABSTRACT: This study examined the decrease in cesarean section rates in relation to perinatal mortality between 1987 and 1993 at the primary referral hospital in north Jordan. Most of the population is at high risk and of low socioeconomic status. The cesarean section rate decreased from 15.5 percent in 1987 to 8.7 percent in 1993, and has remained at this low rate. During the same period the perinatal mortality dropped from 52 to 20.9 deaths per 1000 live births. These results do not include perinatal morbidity. The successful reduction of the cesarean section rate is attributed to active management of labor, trial of labor for women with a previous cesarean birth, and vaginal breech delivery in selected women. We conclude that the rate of cesarean delivery can be safely reduced in a developing country without adverse effects on birth outcomes.  相似文献   
2.
Synthetic lipopeptide analogues of bacterial lipoprotein constitute potent polyclonal activators for monocytes/macrophages and B lymphocytes. However, the fate of the lipopeptides after their interaction with target cells is as yet unknown. In order to follow the routes and to determine the distribution of the lipopeptide within macrophages after stimulation, we investigated lipopeptide-stimulated bone marrow-derived macrophages using the novel method of electron energy loss spectroscopy (EELS). Our results show that the lipopeptide was present in different compartments of the cell. The major amount of the activator was located within the cytoplasm and the plasma membrane, and minor quantities were detected within the nuclear membrane and the nucleus. The distribution of the lipopeptides varied depending on the duration of stimulation. Our results should help to elucidate the molecular mechanisms of macrophage stimulation by lipopeptides or other cell activators.  相似文献   
3.
This study shows that stimulating bone marrow-derived macrophages with either lipopolysaccharide (LPS) or the lipopeptide N-palmitoyl-S-(2,3-bis(palmitoyloxy)-(2RS)-propyl)-(R)- cysteinyl-alanyl-glycine (Pam3Cys-Ala-Gly), a synthetic analogue of the N-terminal part of bacterial lipoprotein, leads to the formation of nitric oxide (NO) and nitrite (NO2-), a stable analogue of NO. NO was detected by applying the chemiluminescence method and by measuring the activity of exogenously added soluble guanylate cyclase (GC), which is strongly and selectively activated by NO. Synthesis of NO and NO2- occurs via activation of the L-arginine and NADPH-dependent enzyme(s) present in the cytosol of bone marrow-derived macrophages. No produced by this non-constitutive L-arginine pathway is thought to be responsible for the cytostatic and killing properties of macrophages (Stuehr & Nathan, 1989). Macrophages stimulated either with LPS or Pam3Cys-Ala-Gly exhibited a 6-hr lag time before engaging in nitrite synthesis, a time at which expression of the NO-forming enzyme had already reached its maximum. The regulation of NO and NO2- synthesis during macrophage development seems to differ from that of cytokine synthesis. Whereas cytokine release varies during a culture period up to 20 days, NO synthesis and expression of the NO-forming enzyme remain unaltered. These studies show that, similar to LPS, Pam3Cys-Ala-Gly is a potent activator of 'the oxidative L-arginine pathway' in bone marrow-derived macrophages. Whether both stimuli use the same signal transfer mechanism to induce this pathway and whether NO synthesized by this pathway is involved in the activation of the enzyme guanylate cyclase in macrophages requires clarification.  相似文献   
4.
PURPOSE: To describe the occurrence and importance of intravascular gas at ultrasonography (US) during the initial examination of patients after blunt abdominal trauma. MATERIALS AND METHODS: Reports of all abdominal US examinations performed at one institution for blunt trauma from October 1995 through June 1996 were reviewed. The charts of patients with intravascular gas were examined to determine the mechanism of injury, associated findings, and clinical outcome. RESULTS: A total of 730 patients underwent abdominal US examinations during the 9 months of study; five had intravascular gas demonstrated. Two patients had portal venous gas, one had hepatic venous gas, and two had inferior vena caval gas. Four of the five patients were involved in motor vehicle accidents, and one had been assaulted. In patients in whom follow-up studies were obtained, there was no evidence of intravascular gas at US or computed tomography. No cause was found at imaging or clinical examination. CONCLUSION: Intravascular gas may occur as a transient incidental finding after blunt abdominal trauma.  相似文献   
5.
OBJECTIVES: Reactions to airborne office dust among healthy subjects and subjects suffering from allergic rhinitis were investigated. METHODS: Twelve healthy and 11 subjects suffering from allergic rhinitis were exposed to clean air [17 (SD 2) microg/m3] and office dust [439 (SD 68) microg/m3] for 245 minutes. The effect measurements included subjective sensations (questionnaire and potentiometer ratings), mood scale, peak flow, bronchial provocation with histamine using forced expiratory volume in 1 second as the effect measure, nasal mucosal swelling, tear film stability, epithelial damage, foam formation in the eye canthus, threshold for eye irritation with carbon dioxide, eye redness, cellular content of conjunctival fluid, and an addition test for distraction. As many investigations were made and as many statistical analyses (including subgroup analyses) were carried out, the risk of mass significance appeared. This problem was dealt with using the Bonferroni correction for multiple significance tests. RESULTS: The mean ratings of the potentiometer were higher (the subjects showed more irritation) during the dust exposure. The objective investigations showed only indications of effects of dust exposure, and some of the indications were in biologically unexplainable directions. No difference in the reactions to dust was observed between the healthy subjects and the subjects suffering from allergic rhinitis. CONCLUSIONS: Dust does not seem to have objective or subjective effects on humans, as only indications of dust effects were found. Subjects suffering from allergic rhinitis do not appear to be a risk group in relation to dust exposure.  相似文献   
6.
7.
This paper investigates the relationship between animal rabies and postexposure treatment (PET) in Ontario by examining the introduction of human diploid cell vaccine (HDCV) in 1980 and the initiation of an oral rabies vaccination program for wildlife in 1989. Introducing HDCV led to an immediate doubling of treatments. Both animal rabies and human treatments declined rapidly after the vaccination program was introduced, but human treatments have leveled off at approximately 1,000 per year.  相似文献   
8.
Thalidomide has been shown to reduce the production of tumor necrosis factor-alpha (TNF-alpha), a cytokine with deleterious pathophysiologic effects in various diseases. In search of thalidomide analogues with improved TNF-alpha inhibiting properties, 5-ethyl-1-phenyl-5-(3,4,5,6-tetrafluorophthalimido)barbituric acid (TFBA) was found to be superior to thalidomide. Besides TNF-alpha, TFBA also suppressed interleukin-6 and interleukin-10 production of isolated monocytes. The possibility that TFBA exerts its action by increasing levels of cAMP via inhibition of phosphodiesterase-4 activity was excluded. TFBA had no influence on T cell proliferation; neither did it inhibit TNF-alpha production in peripheral blood mononuclear cells stimulated by anti-CD3 monoclonal antibody. When applied to mice treated with D-galactosamine and lipopolysaccharide, TFBA prevented a rise in serum TNF-alpha, had no effect on interleukin-6 levels and led to an increase in interleukin-10 production. The changes in cytokine production observed in vitro and in vivo were reflected by similar changes in the mRNA expression. Moreover, TFBA significantly reduced liver transaminase levels in D-galactosamine/lipopolysaccharide-treated mice and thus efficiently protected the animals from liver injury. Thus, according to its properties, TFBA has the potential of modulating an immune response by acting as an anti-inflammatory agent.  相似文献   
9.
The cost-effectiveness of smoking cessation interventions is well documented. However, most studies are based on randomized controlled trials (RCTs) and provide little information on the differences between subgroups. This study assessed the relative cost-effectiveness of smoking cessation interventions offered to various subgroups of smokers, based on real-life data. Regression analyses provided information on the factors determining abstinence and costs and led to the formation of relevant subgroups of smokers. Probabilistic Markov modeling was then used to estimate the relative cost-effectiveness of smoking cessation interventions for the entire database population and for the subgroups compared to a no-intervention case. The ICER for the base case population was estimated at €1,358. This is consistent with results from the existing literature. Group simulations showed lower ICERs for men, hospitals, and light smokers and falling ICERs with increasing age. Despite differences in the cost-effectiveness ratios between subgroups our results do not justify any kind of subgroup differentiation in a smoking prevention policy.  相似文献   
10.
A 50 year old man presented with progressive unilateral cranial nerve palsies (Garcin's syndrome) for one year. Skull radiography and computed tomography (CT) showed intracranial extension of a soft tissue tumour from the right base of the skull. Necropsy revealed a papillary cell carcinoma of the right kidney and metastases in the base of the skull.  相似文献   
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