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71.
Non-Hodgkin's lymphoma (NHL) is the most common human immunodeficiency virus (HIV)-associated malignancy in hemophiliacs. We studied the incidence and clinicopathologic features of NHL in 3,041 hemophiliacs followed at 18 US Hemophilia Centers between 1978 and 1989. Of the 1,295 (56.6%) who were HIV(+), 253 (19.5%) developed acquired immunodeficiency syndrome (AIDS), of whom 14 (5.5%) developed NHL. Three NHL occurred in HIV(-) hemophiliacs, for a 36.5-fold greater risk in HIV(+) than HIV(-) hemophiliacs (P < .001). The NHL incidence rate was 29-fold greater than in the US population by Surveillance, Epidemiology, and End Results (SEER) estimates (P < .001). Between 0 and 4 lymphomas have been observed per year between 1978 and 1989. At presentation 13 (92.9%) of the HIV(+) NHL were extranodal. Ten were stage IV, 1 stage II, and 3 stage IE. Ten (71.4%) were high-grade, 3 (21.4%) intermediate-grade, and 1 (7.1%) was a low-grade B-cell lymphoma. Epstein-Barr virus (EBV) DNA was detected in 36% by in situ hybridization, including one central nervous system (CNS) lymphoma. The mean CD4 cell count at NHL diagnosis was 64/mm3, the mean latency from initial HIV infection was estimated to be 59 months, and the median survival was 7 months. The incidence of basal cell carcinoma in HIV(+) hemophiliacs was 18.3-fold greater than in HIV(-) hemophiliacs (P < .001) and 11.4-fold greater than in the US population (P < .001). In conclusion, incidence rates of NHL and basal cell carcinoma in HIV(+) hemophiliacs are significantly increased over rates in HIV(-) hemophiliacs and over rates in the US population. Clinicopathologic presentation of NHL in HIV(+) hemophiliacs is similar to that in HIV(+) homosexual men.  相似文献   
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Summary Two seriously injured trauma patients presenting with intense and progressive neutropenia are described. Bone marrow examination in both cases showed virtually absent granulopoiesis but normal erythropoiesis and megakaryopoiesis, allowing the diagnosis of acute agranulocytosis. Discontinuation of only one drug (dipyrone) with no further treatment was required for normalization of blood parameters. The association of dipyrone with neutropenia is still debatable. The recent medical literature on dipyrone generation of agranulocytosis is reviewed.  相似文献   
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The respiratory viruses are recognized as the most frequent lower respiratory tract pathogens for infants and young children in developed countries but less is known for developing populations. The authors conducted a prospective study to evaluate the occurrence, clinical patterns, and seasonal trends of viral infections among hospitalized children with lower respiratory tract disease (Group A). The presence of respiratory viruses in children's nasopharyngeal was assessed at admission in a pediatric ward. Cell cultures and immunofluorescence assays were used for viral identification. Complementary tests included blood and pleural cultures conducted for bacterial investigation. Clinical data and radiological exams were recorded at admission and throughout the hospitalization period. To better evaluate the results, a non- respiratory group of patients (Group B) was also constituted for comparison. Starting in February 1995, during a period of 18 months, 414 children were included- 239 in Group A and 175 in Group B. In Group A, 111 children (46.4%) had 114 viruses detected while only 5 children (2.9%) presented viruses in Group B. Respiratory Syncytial Virus was detected in 100 children from Group A (41.8%), Adenovirus in 11 (4.6%), Influenza A virus in 2 (0.8%), and Parainfluenza virus in one child (0.4%). In Group A, aerobic bacteria were found in 14 cases (5.8%). Respiratory Syncytial Virus was associated to other viruses and/or bacteria in six cases. There were two seasonal trends for Respiratory Syncytial Virus cases, which peaked in May and June. All children affected by the virus were younger than 3 years of age, mostly less than one year old. Episodic diffuse bronchial commitment and/or focal alveolar condensation were the clinical patterns more often associated to Respiratory Syncytial Virus cases. All children from Group A survived. In conclusion, it was observed that Respiratory Syncytial Virus was the most frequent pathogen found in hospitalized children admitted for severe respiratory diseases. Affected children were predominantly infants and boys presenting bronchiolitis and focal pneumonias. Similarly to what occurs in other subtropical regions, the virus outbreaks peak in the fall and their occurrence extends to the winter, which parallels an increase in hospital admissions due to respiratory diseases.  相似文献   
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Der Pseudotumor der Orbita ist ein unspezifischer entzündlicher Prozess dessen Genese unbekannt ist und der histologisch in 3 Gruppen unterteilt wird: der granulomat?se, lymphoide und sklerosierende Typ. Zwischen 1995 und 1998 haben wir 12 Patienten mit einem Pseudotumor der Orbita behandelt. Es handelte sich dabei um F?lle vom granulomat?sen (n=6), lymphoiden (n=3) und sklerosierenden (n=3) Typ. Bei 7 Patienten war der Pseudotumor im medialen Bereich der Orbita und in 4 F?llen im lateralen Bereich lokalisiert. Bei einer Patientin lag eine diffuse Infiltration ann?hernd aller orbitalen Strukturen vor. Die Probebiopsie wurde in 6 F?llen endonasal, in 2 F?llen über eine mediale Orbitotomie und bei 4 Patienten über eine laterale Orbitotomie durchgeführt. Die gut abgrenzbaren lymphoiden (n=3) und sklerosierenden (n=3) Pseudotumoren konnten im Rahmen der Probebiopsie komplett entfernt werden, so dass die Patienten nach wenigen Wochen beschwerdefrei waren. Bei den 6 Patienten mit einem granulomat?sen Pseudotumor wurde nach der definitiven Histologie eine prim?re Kortikosteroidtherapie durchgeführt. In 3 der 6 F?lle kam es dadurch zu einem Rückgang der Beschwerden mit kompletter Ausheilung. Bei den restlichen 3 Patienten war eine erneute Kortisontherapie erforderlich wobei diese nur in 2 F?llen erfolgreich war. Der Nachbeobachtungszeitraum betrug 6–28 (Mittel 16) Monate. Postoperative Komplikationen traten nicht auf.  相似文献   
78.
Tobacco use and its concomitant, nicotine dependence, are increasing in African countries and other parts of the developing world. However, little research has assessed nicotine dependence in South Africa or other parts of the African continent. Previous research has found that adolescent problem behaviors, including tobacco use, tend to cluster. This study examined the relationship between nicotine dependence and adolescent problem behaviors in an ethnically diverse sample of urban South African adolescents. A community sample (N = 731) consisting of “Black,” “White,” “Coloured,” and “Indian” youths aged 12–17 years was drawn from the Johannesburg metropolitan area. Structured interviews were administered by trained interviewers. Nicotine dependence was assessed by the Fagerström Test of Nicotine Dependence. Logistic regression analyses showed that higher levels of nicotine dependence significantly predicted elevated levels of violent behavior, deviant behavior, marijuana and other illegal drug use, binge drinking, early sexual intercourse, multiple sexual partners, and inconsistent condom use, despite control on the adolescents’ demographic characteristics, peer smoking, conflict with parents, peer deviance, and the availability of legal and illegal substances. These relationships were robust across ethnicity and gender. The findings indicate the need for policy makers and prevention and intervention programs in South Africa to consider adolescent nicotine dependence in conjunction with comorbid problem behaviors, including other substance use, sexual risk behaviors, and deviant behaviors.  相似文献   
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