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1.
2.
Autopsy samples from the brains of 20 patients who died of falciparum malaria were examined by light microscopy and by an immunohistologic method. Particular attention was paid to a comparison of the pathologic features of the white matter and the cortex. In the high-sequestration (greater than 50%) group (n = 8), the mean +/- SD percentage of cerebral microvessels that showed parasitized red blood cell (PRBC) sequestration was 71.2 +/- 8.1% in the cortex and 84.0 +/- 6.7% in the white matter. The difference in the PRBC sequestration rate between cortex and white matter was statistically significant (P less than 0.01). Perivascular and ring hemorrhages were seen more frequently in the white matter than in the cortex. Deposition of IgG and Plasmodium falciparum antigen in the cerebral microvessels was more highly significant in the white matter than in the cortex (P less than 0.01). Our study demonstrated that the localized concentration of PRBC sequestration in the brain correlated with the marked immunohistologic differences in the microvessels of cortex and white matter.  相似文献   
3.
SummarySymptomatic intracranial stenoses display an increased risk for ischemic stroke. Until now, only retrospective studies have demonstrated a positive effect of oral anticoagulation for prevention of further ischemic strokes. However, this therapy is widely used. The aim of the present study was to examine the efficacy and safety of oral anticoagulation for patients with symptomatic intracranial stenoses in clinical practice. Sixty-one patients with the diagnosis of symptomatic intracranial stenosis between 1992 and 1998 and who received oral anticoagulation were interviewed and examined in 2000. Ten patients suffered ischemic strokes (eight TIA, two completed strokes), and a subdural hematoma occurred in one patient. Six patients died during the observation period. In none of these cases was the death related to oral anticoagulation. Eight extracerebral bleedings occurred. An annual rate of 3% per year for ischemic strokes could be calculated. The annual rates for intracerebral and extracerebral bleeding amounted to less than 1% per year and 2.6% per year, respectively. Thus, oral anticoagulation in patients with symptomatic intracranial stenoses seems to be safe. Although the results suggest its efficacy, this cannot be proven due to the small number of patients examined and due to the design of the study.  相似文献   
4.
Nasolacrimal injuries. Evaluation and management   总被引:2,自引:0,他引:2  
The tear drainage system is disrupted in 17% to 21% of nasoethmoidal fractures and, to a lesser degree, other midfacial fractures. When epiphora or dacryocystitis occurs, evaluation should include the Jones dye tests, probing of the ductal system, or dacryography. Dacryocystorhinostomy is the treatment of obstruction distal to the common canaliculus.  相似文献   
5.
Between 1977 and 1989, 151 patients were treated in our institution for acute sigmoid diverticulitis. Thirty-one patients were operated on for diffuse peritonitis, and were excluded from the study. One hundred twenty patients had localized disease. There were 59 men and 61 women, with a mean age of 60 years (range, 30 to 87 years). Thirteen were under 40 years of age. A phlegmonous diverticulitis (no pericolic abscess) was diagnosed in 78 cases (group I). A pericolic abscess was identified in 42 cases (group II). The medical treatment was successful in 97% of the patients of the group I. Only 15 patients required a delayed elective resection for recurrence or chronic complications, within the next 24 months. There were no operative deaths. All the other patients were doing well after a mean follow-up of 5 years (9–144 months), without any disease-related death. Patients presenting with a localized pericolic abscess (group II,n=42) were initially treated either conservatively (n=22) or by a more or less extensive drainage (n=20). There were two deaths in the conservative group. Primary or delayed colonic resection was indicated in 34 cases because of uncontrolled sepsis, recurrence or secondary chronic complications. It is concluded that accurate classification of the disease is essential. If no peritonitis has developed, the presence of an abscess is the main determinant in both prognosis and treatment. Most patients who develop an acute phlegmonous diverticulitis do well with conservative treatment, and prophylactic resection is not indicated. Curative colectomy is reserved for patients developing persistent complications over the next few months. On the other hand, high rates of recurrence and complication are observed among the patients with a pericolic abscess. Drainage of the abscess, possibly followed by a secondary elective colectomy, could be the appropriate treatment.
Résumé Entre 1977 et 1989 151 malades ont été traités dans notre institution pour une diverticulite aigue du sigmoide. 31 malades ont été opérés pour une péritonite diffuse et ont été exclus de cette étude. 120 malades avaient une maladie localisée. Il y a avait 59 hommes et 61 femmes d'un âge moyen de 60 ans (30–87 ans). 13 étaient âgés de 40 ans ou moins. Une diverticulite phlegmoneuse (sans abcès péricolique) fut diagnostiquée dans 78 cas (groupe I). Un abcès péricolique a été identifié dans 42 cas (groupe II). Le traitement médical fut couronné de succès chez 97 % des patients du groupe I.15 patients seulement ont nécessité une résection élective retardée pour récidive ou complication chronique dans les 24 mois suivants. Il n'y a pas eu décès opératoire. Tous les autres patients allaient bien après une surveillance moyenne de 5 ans (9–144 mois) sans aucune cause de mort en relation avec la maladie. Les patients présentant un abcès péricolique localisé (groupe II,n=42) furent initialement traités soit conservativement (n=22), soit par un drainage plus ou moins extensif (n=20). Il y eut 2 morts dans le groupe conservatif. Une résection colique d'emblée ou retardée fut indiquée dans 34 cas en raison d'une suppuration incontrôlée, d'une récidive ou de complications chroniques secondaires. On conclut qu'une classification appropriée de la maladie est essentielle. Si il n'y a pas de péritonite, la présence d'un abcès est le principal facteur à la fois de pronostic et de traitement. La plupart des patients qui developpent une diverticulite phegmoneuse aigue vont bien avec un traitement conservateur et la résection prophylactique n'est pas indiquée. La colectomie curative est réservée aux patients qui développent des complications chroniques dans les quelques mois suivants. D'autre part, un pourcentage de récidives et de complications élevé fut observé chez les patients qui avaient un abcès péricolique. Le drainage de l'abcès, eventuellement suivi d'une colectomie élective secondaire, pourrait être le traitement approprié.
  相似文献   
6.
Helicobacter pylori-associated diseases, such as peptic ulcer and gastric cancer, are common in Vietnam, but the prevalence of the infection is largely unknown. A validated enzyme-linked immunosorbent assay was used for seroepidemiology with 971 samples from the general population, ages 0 to 88 years, with 546 samples from an urban population (Hanoi), and with 425 samples from a poor, rural province (Hatay). The overall seroprevalence of the infection was 746 per 1,000, with a prevalence of 788 per 1,000 in Hanoi and 692 per 1,000 in Hatay (P = 0.0007). The risk for infection in the rural area of Hatay was 40% lower than in the urban population of Hanoi, with the odds ratio being 0.59 (95% confidence interval, 0.43 to 0.81). The study shows that the prevalence of H. pylori infection is high in Vietnam and especially high in a large urban area, such as the city of Hanoi.  相似文献   
7.
C3H/HeJ mice received B10.BR skin grafts following portal or lateral tail vein infusion of irradiated B10.BR spleen cells. Thereafter mice were injected with anti-alpha beta or anti-gamma delta T-cell receptor (TCR) monoclonal antibody (mAb). Anti-gamma delta TCR mAb abolished the increased graft survival afforded by portal venous (p.v.) immunization, and reversed the bias towards expression of mRNA for type-2 cytokines [interleukin-4 (IL-4), IL-10] seen in lymphoid tissue of p.v.-immunized mice. When gamma delta TCR+ and alpha beta TCR+ cells were isolated from the intestinal epithelial compartment (IEL), liver or Peyer's Patch (PP) of p.v.-immunized mice, the gamma delta TCR+ cells were found to be enriched in cells producing type-2 cytokines on rechallenge with irradiated B10.BR cells in vitro. gamma delta TCR+ cells from p.v.-immunized mice were further expanded in vitro with anti-CD3 and cytokines (combined IL-2 and IL-4). Following expansion these cells were capable of adoptively transferring increased B10.BR skin graft survival to naive mice, and continued to show a bias in type-2 cytokine synthesis after allostimulation in vitro. When gamma delta TCR chain expression was assessed in cells taken from p.v.-immunized mice, or in cells expanded in culture, our data suggest that p.v. immunization leads to oligoclonal, not polyclonal, expansion of those gamma delta TCR+ cells involved in inhibition of graft rejection.  相似文献   
8.
Primary subcutaneous phaeohyphomycosis can rarely be caused by Cladophialophora bantiana, and we present the histologic and culture findings of such a case. A 32-year-old African American woman with systemic lupus erythematosus presented with a 2-year history of multiple, recurrent, tender, and ulcerated skin nodules with purulent drainage on her upper back. Histologic sections of the excision demonstrated features of phaeohyphomycosis. Culture findings were characteristic of C bantiana. Of interest, at age 10 she had sustained traumatic implantation of wood splinters into this area during a tornado, yet clinical symptoms of a subcutaneous infection did not manifest until she developed lupus erythematosus at age 27. Our case highlights the role of trauma and immunosuppression in the pathogenesis of subcutaneous phaeohyphomycosis.  相似文献   
9.
R M Gorczynski  S Chung  Y Hoang  B Sullivan    Z Chen 《Immunology》1996,87(4):573-580
Naive or preimmunized (to B10.BR or BALB.k) C3H/HeJ mice received skin grafts from multiple minor histoincompatible B10.BR or BALB.k mice following antigen-specific portal venous (p.v.) pretransplant transfusion, a protocol known to produce prolongation of graft survival in naive animals. In addition, groups of mice received intravenous (i.v.) infusion following transplantation with a mixture of monoclonal antibodies (mAb) to vascular adhesion molecule-1L: very late activation antigen-4 (VCAM-1:VLA-4) or intracellular adhesion molecule-1:lymphocyte function-associated antigen-3 (ICAM-1:LFA-1). Cells were harvested from different tissues of the grafted mice at various times post grafting. RNA was extracted and analysed, using polymerase chain reaction, for expression of different cytokines potentially involved in the regulation of graft rejection [interleukin-2 (IL-2), IL-4, IL-6, IL-10, tumour necrosis factor-alpha, interferon-gamma and transforming growth factor-beta]. In addition, using limiting dilution analysis, we investigated the frequency of allo-specific and third-party reactive cells producing IL-2 and IL-4 in vitro in different tissues of grafted mice following these treatments. The mAb treatment protocol which produced optimum increases in graft survival in naive versus immune mice was different, with anti-LFA-1:ICAM-1 superior for naive mice compared with anti-VLA-4:VCAM-1, and vice versa for immune animals. However, in each case, increased survival was associated with increases local to the graft in the frequency of occurrence of antigen-specific type-2 cytokine-producing cells.  相似文献   
10.
Human herpesviruses are associated with morbidity and mortality in persons with compromised immune systems, including patients infected with human immunodeficiency virus (HIV). To investigate the basis for this association, the levels of all 8 human herpesviruses (herpes simplex virus, types 1 and 2, varicella-zoster virus, cytomegalovirus, Epstein-Barr virus, and human herpesvirus 6, human herpesvirus 7, and human herpesvirus 8) were measured with the quantitative polymerase chain reaction (PCR). Viral DNA was measured in the whole blood of 20 HIV-infected patients and compared with levels in 20 healthy blood donors. There was no significant difference in the frequency of virus detection of the 8 human herpesviruses between HIV-infected patients and healthy adults. These results indicate that HIV infection is not associated with a general increase in the circulating levels of human herpesviruses, and suggest that quantitative PCR analysis is superior to qualitative PCR analysis for detection of clinically relevant disease in HIV-infected patients.  相似文献   
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