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81.
BACKGROUND: The World Health Organization advocates 2-3 doses of sulfadoxine-pyrimethamine (SP) for intermittent preventive treatment of malaria (SP IPTp). The optimal number of doses and the consequences of single-dose therapy remain unclear.METHODS: Data were from a randomized, controlled study of human immunodeficiency virus-positive Zambian women comparing monthly versus 2-dose SP IPTp. We compared maternal and neonatal birth outcomes as a function of how many doses the mothers received (1 to > or =4 doses).RESULTS: Of 387 deliveries, 34 received 1 dose of SP. Single-dose SP was significantly associated with higher proportions of maternal anemia, peripheral and cord blood parasitemia, infant prematurity, and low birth weight. SP conferred dose-dependent benefits, particularly in the transition from 1 to 2 doses of SP. Women randomized to the standard 2-dose regimen were much more likely to receive only 1 dose than were women randomized to monthly IPT (relative risk, 16.4 [95% confidence interval, 4.0-68.3]).CONCLUSIONS: Single-dose SP was a common result of trying to implement the standard 2-dose regimen and was inferior to all other dosing regimens. At a programmatic level, this implies that monthly SP IPTp may ultimately be more effective than the standard regimen by reducing the risk of inadvertently underdosing mothers.  相似文献   
82.
This study examined whether (1) parents of anxiety-disordered (AD) children differed from those of non-clinical controls in their childrearing style, and whether (2) the child-rearing style of parents towards AD children is different from that towards their siblings. A clinical sample of 25 AD children, age range 8–13 years, was compared with 25 siblings and a non-clinical control group (n = 25). Childrearing was assessed by means of parental self-report, child report and through an expressed emotion interview measure. AD children perceived more parental rejection than non-clinical control children or the AD children’s siblings. High-expressed emotion was scored significantly more often towards AD children than non-clinical control children, or their siblings. On ‘care’ and ‘control’ parental self-report showed some differences regarding AD children on the one hand and non-clinical control children or siblings of AD children on the other. These results suggest that the rearing of AD children differs significantly both from the rearing of their siblings and that of non-clinical control children. I. E. Lindhout and F. Boer were with the Academic Centre for Child and Adolescent Psychiatry Curium, Oegstgeest, and Leiden University Medical Centre, Leiden, The Netherlands, at the time of the study.  相似文献   
83.
BACKGROUND: The clearance of D+ red blood cells (RBCs) from the circulation in D- individuals mediated by passively administered anti-D occurs by opsonization with the antibody and subsequent removal in the spleen. Few data exist on the kinetics of clearance of large volumes of D+ RBCs from the maternal circulation by anti-D in clinical cases of massive fetomaternal hemorrhage (FMH). CASE REPORT: A 33-year-old D- woman delivered a D+ female infant by emergency cesarean section for suspected fetal anemia. A massive FMH, initially estimated to be approximately 142 mL of RBCs, was found. In addition to the standard dose of intramuscular (IM) anti-D (300 microg) given immediately after delivery, 2700 microg of anti-D was administered intravenously (IV). The clearance of D+ fetal cells from the maternal circulation was monitored by flow cytometry in samples obtained on a daily basis using anti-D. The mother had no detectable anti-D 6 months after delivery. RESULTS: No clearance of fetal cells was apparent after the insufficient dose of IM anti-D. The IV administration of anti-D caused accelerated clearance of D+ fetal RBCs with a t1/2 of 24.5 hours. D+ reticulocytes comprised 4.2 percent of all D+ cells in the maternal circulation at delivery suggesting acute fetal blood loss. CONCLUSIONS: The approach used in this report allowed a detailed analysis of the kinetics related to the clearance of fetal D+ RBCs. Simultaneous measurements of fetal reticulocytes and fetal RBCs in maternal blood may establish the timing of an FMH.  相似文献   
84.
85.
Contingent shock (CS) has been used in a number of studies to suppress health-threatening self-injurious behavior of individuals with mental retardation and autism. As sustained suppression is an issue of concern, research into procedural variables of CS is needed. In this study, clinical evidence was used to infer a variable that might be of relevance for the application of clinical contingent shock, that is, to assess the effect of single versus repeated shock at a specific location on the body. With pain intensity and startle response as dependent variables, shocks were administered to 48 healthy volunteers. Electric shocks were identical to those that used in clinical practice. The second shock in succession to the same location of the body produced higher pain intensity ratings than the first shock and that the third shock in succession to the same location of the body produced higher pain intensity ratings than the second shock in succession. Startle responses, however, failed to be affected in this direction. The latter result is consistent with a previous study. Our data suggest that repeated shock to the same location is likely to be more effective to establish suppression than repeated shock to different locations.  相似文献   
86.
Immunological interventions in endotoxemia and sepsis have been tested in experimental and clinical studies. Our group evaluated the effects of an immunoglobulin (Ig)M-enriched solution in an established model of Gram-negative bacteraemia. Ten New Zealand White rabbits (2-3 kg) were randomized to a treatment or control group. In both groups, LPS was infused at a rate of 40 mg kg(-1) h(-1). Immunoglobulin M-enriched solution (Pentaglobin; 2 mL kg(-1) h(-1)) was applied in the intervention group 15 min after beginning LPS infusion. 1 x 10(8) colony forming units of Escherichia coli were injected 30 min after LPS infusion was commenced. Baseline hemodynamic and respiratory parameters, blood E. coli concentration (30 min before and 1, 15, 30, 60, 90, 120, and 180 min after E. coli injection), polymorphonuclear neutrophil oxidative burst activity, and phagocytosis dead space (both 30 min before and 1, 15, 60, 120, and 180 min postinjection) were measured. Ex vivo phagocytosis activity was measured in a separate experiment and evaluated by electron microscopy. Diffuse alveolar damage (DAD) was measured. Organ colonization (kidney, lung, liver, spleen) was assessed in aseptic organ samples. Hemodynamic parameters did not differ between the two groups. Bacterial blood clearance was not influenced by application of IgM-enriched solution. Liver and spleen colonization was significantly reduced in the IgM group. Immunoglobulin M-enriched solution reduced in vitro residual phagocytosis capacity at 30, 90, and 180 min and improved respiratory burst at 180 min. Correspondingly, ex vivo phagocytosis activity as documented by electron microscopy was increased in the IgM group. The sum of all weighted DAD scores (except overdistension) was significantly better in the IgM group (23+/-5 vs. 30+/-8). Immunoglobulin M-enriched solution significantly improved six of seven DAD score parameters and reduced liver and spleen E. coli count. Residual phagocytosis capacity was significantly decreased in the IgM group, whereas burst activity was increased, pointing to an increased in vivo phagocytosis efficiency. Short-term IgM-enriched solution intervention had an especially beneficial effect on LPS-induced pulmonary histological changes.  相似文献   
87.
Enterococcal meningitis is a rare complication of neurosurgical procedures. We present a patient who developed vancomycin-resistant enterococcal ventriculitis - meningitis after a brain tumor resection and ventriculoperitoneal shunt placement, treated successfully with intrathecal streptomycin through bilateral cerebrospinal fluid drainage catheters in addition to systemic antibiotics. This is the first report of such treatment for this resistant organism.  相似文献   
88.
In this study we developed a refined pharmacophore model for antagonists of the human adenosine A1 receptor, based on features of known pyrimidine and purine derivatives. The adoption of these updated criteria assisted us in synthesizing a series of 1-deazapurines with consistently high affinity as inverse agonists for the adenosine A1 receptor. These 1-deazapurines (otherwise known as 3H-imidazo[4,5-b]pyridines) were substituted at their 2- and 6-positions, yielding a series with five of the derivatives displaying Ki values in the subnanomolar range. The most potent of these, compound 10 (LUF 5978), displayed an affinity of 0.55 nM at the human adenosine A1 receptor with >300-fold and 45-fold selectivity toward A2A and A3 receptors, respectively. Compound 14 (LUF 5981, Ki = 0.90 nM) appeared to have the best overall selectivity with respect to adenosine A2A (>200-fold) and A3 (700-fold) receptors.  相似文献   
89.
90.
Persistent diarrhea associated with AIDS   总被引:1,自引:0,他引:1  
Chronic diarrhea and wasting are very common manifestations of AIDS in adults in developing countries. Etiologic studies show that protozoa (including Cryptosporidium parvum, Isospora belli , and Enterocytozoon bieniusi ) and Mycobacterium avium-intracellulara are the most frequently identified pathogens. Limited data in children suggest that common enteric pathogens are equally as likely in HIV+ and HIV- babies. Preliminary analysis of an ongoing longitudinal study of 469 babies born to mothers with known HIV serostatus in Kinshasa, Zaire, reveals progression of acute to persistent diarrhea is six times greater in HIV+ compared to HIV- babies, and 3.5 times greater in HIV- babies born of HIV+ mothers in comparison to HIV- babies with HIV- mothers. HIV+ babies were also at greater risk than HIV- babies to have recurrent episodes of diarrhea (RR = 2.3). Fifty percent of the deaths were due to acute or persistent diarrhea, and were strongly associated with HIV infection. Efforts to improve child survival in AIDS infected populations will need to address HIV infections in both mothers and infants.  相似文献   
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