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91.
92.
Patients on hemodialysis are at increased risk for developing active tuberculosis (TB) after primary infection. Although this increased risk is well documented, the prevalence of TB infection, as indicated by a positive tuberculin skin test (TST), is not well described. End-stage renal disease is also known to be a risk factor for skin test anergy, but the rate of anergy in hemodialysis patients is unclear. We sought to identify rates of anergy and TST positivity in patients at four hemodialysis units in St Louis, Missouri, from June 1996 through August 1996. Data obtained from patients and medical records included age, years on hemodialysis, medical history, and basic laboratory data. Patients without a history of TB or a positive TST had a TST with Tubersol, as well as candida and tetanus controls, placed by the Mantoux method. Tests were read 48 hours later. Of the patients enrolled at these units, 307 of 331 (93%) were evaluated. Patients had a mean age of 58 years (range, 19 to 91 years) and had been on hemodialysis for a mean of 3.7 years (range, 1 week to 18.7 years). Blacks made up 81% of the population. A history of a positive TST was obtained from 24 patients (8%), and an additional seven (2%) had a history of active TB. Of the 276 patients tested, 93 did not respond to either control antigen, but five of these patients had a positive TST, leaving 88 (32%) anergic. Anergy was related to age, immunosuppressive drug use, and the reagents used, but not to urea reduction ratio. Positive TSTs were found in 17 of 188 of nonanergic patients (9%) (6% of all tested patients). Overall, 48 of 307 patients (16%) had a positive TST or history of TB. TB or a positive TST was associated with liver disease and peptic ulcer disease, but not socioeconomic status. All 17 newly identified TST-positive patients received chest radiographs. No new cases of active TB were found. Only two of 17 of these patients (12%) were started on isoniazid (INH) prophylaxis. We identified high rates of TST positivity and anergy in the hemodialysis patients tested. Hemodialysis patients should receive regular TST screening, and INH prophylaxis needs to be more strongly encouraged. Studies are ongoing to define the rate of TST conversion over time.  相似文献   
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Zusammenfassung Von 1980–1987 wurden 95 Patienten mit einem Ösophaguskarzinom bronchoskopiert. Bei 67 Patienten (70,5%) wurde ein regelrechter Befund erhoben. 24 Patienten (25,3%) zeigten in der Bronchoskopie indirekte Zeichen des Tumorwachstums and 4 Patienten (4,2%) eine direkte Tumorinfiltration. Die Korrelation der Tumorausdehnung mit dem bronchoskopischen Befund ergab eine deutliche Zunahme pathologischer bronchoskopischer Befunde bei einer Tumorlönge über 5 cm. Ösophaguskarzinome im proximalen Drittel waren etwa doppelt so hdufig mit pathologischen bronchoskopischen Befunden korreliert wie Karzinome im mittleren Drittel. Bei 5 Patienten (5,3%) sicherte die Bronchoskopie ein bis dahin unbekanntes zusdtzliches Bronchialkarzinom. Insgesamt wurden 67 der 95 Patienten einer operatven Therapie unterzogen. In 59 Fdllen erfolgte die Ösophagusresektion, bei 8 Patienten war lediglich eine Bypassoperation möglich. Die Operationsrate betrug im Kollektiv der bronchoskopischen Normalbefunde 77,6%. Dagegen waren nur die Hdlfte der Patienten mit einem pathologischen bronchoskopischen Befund operabel, die übrigen Patienten erhielten eine Strahlentherapie. Wir halten die Bronchoskopie wegen ihres Beitrages zur Kldrung der Operabilität bei Ösophaguskarzinomen and wegen der relativ hohen Rate von synchronen Neoplasien für eine sinnvolle Zusatzuntersuchung.
Is bronchoscopy a useful preoperative examination in patients with esophageal carcinoma?
Summary Between 1980 and 1987 95 patients with esophageal carcinoma had a bronchoscopy. In 67 patients (70.5%) no pathological findings could be detected. In 24 patients (25.3%) signs of impingement were present and in 4 patients (4.2%) tumor infiltration into the tracheobronchial tree was visible. The correlation between tumor length and bronchoscopic findings revealed a marked increase of direct and indirect tumor evidence in esophageal carcinomas of more than 5 cm in length. Pathologic bronchoscopic findings were detected twice as often in patients with carcinoma of the upper third of the esophagus in comparison with those of the middle third. In 5 patients (5.3%) bronchoscopy revealed an unknown additional bronchial carcinoma. 67 of the 95 patients underwent operation. In 59 patients the esophagus was resected. Among the normal bronchoscopic findings the operability rate was 77.6%. In contrast, only half of the patients with pathological bronchoscopic findings were operable, the other patients received radiotherapy. We recommend, therefore, preoperative bronchoscopy as an important investigation for assessment of operability and for evaluation of synchronous neoplasms in patients with an esophageal carcinoma.
  相似文献   
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OBJECTIVES: To determine the economic and clinical outcomes associated with infection with vancomycin-resistant Enterococcus (VRE) and to compare these outcomes to those associated with infection with vancomycin-sensitive Enterococcus (VSE). METHODS: During a 3-month, prospective, cohort study of 117 high-risk, critically ill patients we collected complete clinical and demographic and ICU cost data from all patients during their ICU stays. RESULTS: After adjusting for variables in a stepwise multiple regression model VRE infections were associated with a median attributable increased ICU cost per patient of $33,251 (38,088 euros) and an increased length of hospital stay (LOS) of 22 days, while VSE infections were associated with an increased cost of $21,914 (25,102 euros) and an increased LOS of 27 days. The effect of VRE and VSE infections were not significantly different. Over the entire cohort the attributable cost per ICU patient day associated with VRE infection was $304 (348 euros). CONCLUSIONS: The attributable cost of ICU care associated with VRE infection is $33,251 (38,088 euros) and per ICU patient day was $304 (348 euros). VRE and VSE infections do not differ in associated cost of ICU care, LOS, or mortality. Any VRE control strategy is be cost-effective if the overall cost per ICU patient-day is less than $304 (348 euros).  相似文献   
97.
Andreesen  R; Bross  KJ; Osterholz  J; Emmrich  F 《Blood》1986,67(5):1257-1264
We have analyzed the expression of late differentiation antigens during terminal in vitro maturation of human macrophages (M phi) from blood monocytes (MO) in comparison to their distribution among mature M phi residing in various tissue sites. By immunizing mice with M phi derived from blood MO by culture on hydrophobic Teflon foils, monoclonal antibodies (mAbs) were developed (MAX.1, MAX.2, MAX.3, MAX.11) that reacted with lineage-restricted differentiation antigens. These antigens were expressed exclusively on M phi or were markedly increased after in vitro differentiation. The only overlap to another hemopoietic cell lineage was observed with MAX.3, which is shared by platelets and megakaryocytes. In the course of M phi maturation in vitro, the MAX.1 and MAX.3 antigens are detected within the cytoplasm two days before they appear on the cell surface. In contrast, the MAX.11 antigen is expressed simultaneously in the cytoplasm and at the cell surface, is found in varying degrees on a minor portion of blood MO and U937 cells, and is expressed rapidly at high density during early M phi differentiation in vitro. Among conventional mAbs that do not react with MO we found those against the transferrin (TF)-receptor, the BA-2, and the PCA1 antigen to label M phi. M phi matured in vivo and isolated from body fluids were positive with some but not all MAX mAbs. Distinctive patterns were observed with pulmonary M phi, exudate M phi from pleural and peritoneal effusions, synovial fluids, and early lactation milk. M phi from the alveolar space, for example, constantly expressed the MAX.2 antigen but not the MAX.3 antigen. Pleural effusion M phi, however, did not react with the MAX.1 mAb, but in most cases, it did react with the MAX.3 mAb. The detection of novel differentiation antigens, all expressed on monocyte-derived M phi but differently expressed on site-specific M phi in situ, underlines the remarkable heterogeneity among human M phi. The expression of these antigens is flexible because those MAX antigens that were not expressed in situ could be induced if cells from distinct tissue sites were cultured in vitro for several days. MAX mAbs may be of potential value to study both the sequential stages of maturation within the M phi lineage as well as differential developments induced by various culture conditions in parallel to environmental factors in vivo.  相似文献   
98.
以动脉粥样硬化为基础的心血管疾病是人类健康面临的严重挑战.人们对动脉粥样硬化发生、发展进行漫长和不懈的探索.至今,其机制与过程仍不十分清楚.  相似文献   
99.
Archivum Immunologiae et Therapiae Experimentalis - Conventional anti-cancer drugs preferentially eliminate differentiated cancer cells but those cells that are spared (i.e. cancer stem cells:...  相似文献   
100.
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