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61.
Severe malaria in children in Papua New Guinea   总被引:1,自引:0,他引:1  
The clinical features of severe falciparum malaria and risk factors for mortality were studied in 489 children admitted with malaria to Madang Hospital, Papua New Guinea. The most common severe manifestations of malaria were severe anaemia (22%) and coma (16%). Children with severe anaemia were younger than those with coma (median age 2.2 vs. 3.7 years) and had been ill for longer before admission (median 7 vs. 4 days, respectively). Although the clinical features of coma in Madang children with malaria resembled closely those reported in African children, mortality was lower (8% vs. 17-25%, respectively). Overall, 17 (3.5%) children died, most within 12 h of admission. A high level of plasma lactate (> or = 5 mmol/l) was common (20%) and was the major predictor of death in multiple regression analysis. Raised plasma creatinine and decreased plasma bicarbonate were also independent predictors of mortality. Coma was not predictive of death, although a high proportion of children with profound coma died. Investigation of the causes of acidosis in children with malaria is a high research priority. In view of the short time interval between admission and death in many children, emphasis must be placed on the prevention or early recognition and treatment of acidosis in the district health clinic as well as the central hospital.   相似文献   
62.
A medicoeconomic evaluation of continuous intrathecal baclofen (Lioresal®) infusion for symptomatic treatment of severe spinal spasticity was realised using a monocentric, comparative, retrospective approach where subjects were their own controls (n = 22). Study results confirm the efficacy of baclofen on symptoms, functional status of patients and on a non specific quality of life scale. Conversely, use of baclofen lead to a 67% increase of average annual costs of care for these patients and reaches around 173,500 French francs (~29,000 US$)/year. Such a cost seems to be acceptable with respect to clinical benefits. © 1998 Elsevier, Paris  相似文献   
63.
胎儿和新生儿同种免疫性血小板减少症(alloimmune thrombocytopenia,AIT)的发生是由于胎儿的血小板特异性抗原刺激母体产生同种抗体而引起的。胎儿的这种特异性抗原来源于父亲。通常,胎儿和新生儿发生严重AIT绝大多数是由于胎儿-母体PIA1抗原不相容所致,估计这种病例有20%可并发颅内出血。最近,在挪威和苏格兰进行的AIT发生率的前瞻性研究中发现因PIA1所致的新生儿AIT的发病率大约是1%。由于AIT与其他病因引起的新生儿血小板减少症的治疗方法不同,故对AIT的快速诊断将有助于患儿获得最佳治疗。本研究比较了血清学诊断为AIT的新生儿与血清学不支持诊断为  相似文献   
64.
胎儿和新生儿同种异体免疫性血小板减少症(AIT)是引起胎儿和新生儿严重血小板减少的最常见原因.母亲针对源自父亲的胎儿血小板抗原的IgG抗体,在妊娠早期就可通过胎盘,通常导致胎儿严重血小板减少.由于一些血小板减少症临界值(50、100或150×109/L)的不同,他们的发生率亦各不相同.但在多数未经选择的人群中,AIT影响1/1 000到1/2 000活产数.在新生儿病房,临床确诊的重症AIT很罕见,可能只有1:10 000分娩数.  相似文献   
65.
Heart-reactive antibody (HRA) appears in the sera of experimental animals inoculated with group A streptococci as well as patients with acute rheumatic fever. Adsorption of either serum with group A streptococcal membranes will remove the HRA. Blocking experiments between these two types of HRAs have demonstrated that the antibodies are directed towards different antigenic determinants on either the same or different molecules. To isolate and purify the antigen from the group A streptococcus cross-reactive with sarcolemmal sheaths of cardiac myofibers, it became necessary to purify the HRA from rheumatic fever patients’ sera. Isolated gamma globulin containing all of the HRA was adsorbed onto human sarcolemmal sheaths. The specific HRA was released by using potassium iodide. Over 99 percent of the purified HRA was shown to bind the sarcolemmal sheath whereas less than 1 percent of the antibody would bind nonspecifically to other material. Preparations of group A streptococcal membrane will bind HRA purified from the sera of acute rheumatic patients at levels of 97 percent or greater. The cross-reactive antigen solubilized by nonionic detergent was purified 120-fold by column chromatography. On sodium dodecyl sulfate polyacrylamide electrophoresis, the antigen was demonstrated to be composed of four polypeptides with mol wt of 32,000, 28,000, 26,000, and 22,000 daltons, respectively. Only proteolytic enzymes could destroy the antigenic determinant whereas glycosidases and lipases had no effect. The purified antigen blocked the binding of purified HRA to normal human heart sections.  相似文献   
66.
SUMMARY A case of cord presentation associated with the presence of a complex true knot is described and the aetiology and risks reconsidered.  相似文献   
67.
We determined the prevalence of antibody to cytomegalovirus (CMV) in the sera of non-homosexual hemophilia patients and homosexual men infected with the human immunodeficiency virus type 1 (HIV-1). CMV antibody testing by latex agglutination revealed 33 of 58 HIV-1 infected hemophiliacs (57%) were antibody-positive compared with 54 of 54 HIV-1 infected asymptomatic non-hemophiliac homosexuals (100%) (p less than .001). Nine of 15 hemophiliacs (60%) with symptomatic HIV-1 infection were CMV antibody-positive. We also tested 22 HIV-1 antibody-negative hemophiliacs who had received non-heat treated factor concentrates. 14 of these 22 (64%) were CMV antibody-positive compared with 57% of HIV-1 antibody-positive hemophiliacs. We conclude 1) there is little correlation between transmission of HIV-1 and CMV by factor concentrates, 2) the presence of CMV antibody does not appear to be associated with clinical stage of HIV-1 infection in hemophiliacs, and 3) there may be a significant number of CMV antibody-negative hemophiliacs with HIV-1 infection at risk for primary infection and subsequent disease if CMV seronegative blood products are not provided for future transfusions.  相似文献   
68.

Background  

Patients with diabetic polyneuropathy (DPN) are often confronted with ulceration of foot soles. Increased plantar pressure under the forefoot has been identified as a major risk factor for ulceration. This study sets out to test the hypothesis that changes in gait characteristics induced by DPN related muscle weakness are the origin of the elevated plantar pressures.  相似文献   
69.

Background and purpose:

α- and β-amyrin are pentacyclic triterpenes found in plants and are known to exhibit pronounced anti-inflammatory effects. Here, we evaluated the effects of a 1:1 mixture of α- and β-amyrin (α,β-amyrin) on an experimental model of colitis in mice.

Experimental approach:

Colitis was induced in Swiss male mice by trinitrobenzene sulphonic acid (TNBS) and followed up to 72 h; animals were treated systemically with α,β-amyrin, dexamethasone or vehicle. Macro- and microscopic damage, myeloperoxidase activity and cytokine levels were assessed in colons. Histological sections were immunostained for cyclooxygenase-2 (COX-2), vascular endothelial growth factor, phospho-p65 nuclear factor-κB (NF-κB) and phospho-cyclic AMP response element-binding protein (CREB)

Key results:

TNBS-induced colitis was associated with tissue damage, neutrophil infiltration and time-dependent increase of inflammatory mediators. Treatment with α,β-amyrin (3 mg·kg−1, i.p.) or dexamethasone (1 mg·kg−1, s.c.) consistently improved tissue damage scores and abolished polymorphonuclear cell infiltration. α,β-Amyrin, like dexamethasone, significantly diminished interleukin (IL)-1β levels and partially restored IL-10 levels in colon tissues 72 h after colitis induction, but only α,β-amyrin reduced vascular endothelial growth factor expression by immunohistochemistry. The colonic expression of COX-2 at 24 h and that of phospho-NF-κB and phospho-CREB (peaking at 6 h) after colitis induction were consistently inhibited by both α,β-amyrin and dexamethasone.

Conclusions and implications:

Systemic administration of α,β-amyrin exerted a marked and rapid inhibition of TNBS-induced colitis, related to the local suppression of inflammatory cytokines and COX-2 levels, possibly via inhibition of NF-κB and CREB-signalling pathways. Taken together, our data suggest a potential use of α,β-amyrin to control inflammatory responses in bowel disease.  相似文献   
70.
Intrakranielle Blutungen (ICB) machen etwa 15% aller Schlaganf?lle aus. In der Notfallsituation ist die CT der derzeitige diagnostische Standard zur Differenzierung zwischen hyperakuter ICB und zerebraler Isch?mie. Der MRT wird im Akutstadium ein geringer Stellenwert für die Diagnose einer ICB oder Subarachnoidalblutung (SAB) beigemessen und viele Autoren bescheinigen der MRT eine niedrige Sensitivit?t für hyperakute ICB. Wir geben eine übersicht über die aktuelle Literatur und charakterisieren den Stellenwert der MRT bei der Diagnose von ICB und SAB sowie hyperakuter Schlaganf?lle im Allgemeinen: MRT-Signalcharakteristika von ICB beruhen auf dem H?moglobinabbau. Bei subakuten und chronischen ICB/SAB ist die MRT der CT überlegen, bei hyperakuten ICB herrscht diesbezüglich Dissens. Deoxyh?moglobin, dessen paramagnetische Eigenschaften einen Signalverlust in suszeptibilit?tsgewichteten Sequenzen (T2*-WI) bewirken, ist das Substrat des MRT-Nachweises akuten Blutes. Vorl?ufige Daten legen eine hohe Sensitivit?t moderner Schlaganfall-MRT Protokolle auch für hyperakute ICB und SAB nahe. Au?erdem k?nnen durch die MRT zus?tzliche Informationen zur ?tiologie einer ICB oder SAB erlangt werden. Von weiterem Interesse sind perih?morrhagische pathophysiologische Abl?ufe, deren Charakterisierung bei ICB-Patienten evtl. eine Verbesserung des Therapiemanagements mit sich bringt.  相似文献   
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