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Leukemic cells from a series of patients with chronic B-lymphocytic leukemia (CLL) were analyzed for their buoyant density on discontinuous Percoll gradients. The density profile varied markedly between different patients and also between samples from different body compartments within the same patient. A good correlation was observed between buoyant density and maturation stage of the leukemic clones as judged by Ig-expression and their reactivity with a panel of monoclonal antibodies. Phorbol-ester-induced changes in the leukemic cells were found to be accompanied by a general decrease in their buoyant density. No correlation between density and clinical parameters such as cell counts, clinical stage and survival could be noted. Buoyant density characterization of leukemic B-cell populations is seen as a useful, rapid and simple marker of compartmentalization within the B-lymphocyte maturation spectrum but its clinical relevance remains to be established.  相似文献   
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Zusammenfassung Eine hochgradige Duodenalstenose im Erwachsenenalter kann in seltenen Fällen angeboren sein und findet ihre Ursache in einer intraduodenal gelegenen Membran. Die Anamnese zeigt Wachstumsstörungen mit Erbrechen und Meteorismus und abdominelle Beschwerden. Eine Perforationsöffnung in dieser Membran ist die Ursache fur ein Überleben bis ins Erwachsenenalter. Die Röntgendarstellung und die tiefe Duodenoskopie lassen auf einfache Weise die Diagnose stellen. Differentialdiagnostisch müssen der Volvulus bei Malrotation, Ladd-Bänder und das Pancreas anulare, sowie die Kompression des Duodenums durch Mesenterialgefäße erwogen werden. Das operative Verfahren der Wahl ist die Resektion der intraduodenalen Membran. Dabei ist v. a. die Papilla Vateri darzustellen, da diese nicht selten im Bereich des Septums mündet. Das längs eröffnete Duodenum wird quer verschlossen. Bei der Wind-Sock-Web-Anomalie sollte das Duodenum an der Ansatzstelle des Diaphragmas eröffnet werden. Die Anlage einer Gastrojejunostomie ist inadäquat und zu vermeiden.
Congenital duodenal stenosis in adulthood
A high-grade duodenal stenosis in adults can, in rare cases, be congenital, and its cause is found in an intraduodenally sited membrane. The anamnesis reveals growth disorders with vomiting and meteorism and abdominal complaints. A perforation opening in this membrane is the reason for survival into adulthood. The X-ray appearance and deep duodenoscopy make the diagnosis easy. Volvulus in cases of malrotation, Ladd's ligaments, anular pancreas, and compression of the duodenum by mesenteric vessels must be considered in the differential diagnosis. When the intraduodenal membrane is resected it is most important to expose the papilla Vateri, since this not uncommonly ends in the area of the septum. If necessary, a duodenoduodenostomy is performed. If the windsock web abnormality is present the duodenum should be opened at the point of attachment of the diaphragm. The construction of a gastrojejunostomy should be avoided.
  相似文献   
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OBJECTIVE: To compare the clinical efficacy and safety of trimethoprim-sulfamethoxazole (TMP-SMX) with pentamidine in the therapy of Pneumocystis carinii pneumonia (PCP) in patients with AIDS. PATIENTS, PARTICIPANTS: TMP-SMX (TMP, 20 mg/kg/day plus SMX, 100 mg/kg/day) was compared with pentamidine (4 mg/kg/day), both administered intravenously for 21 days in a prospective randomized treatment trial of 163 patients diagnosed with PCP between November 1984 and May 1988. RESULTS: Ninety-two evaluable patients received TMP-SMX as initial therapy; 68 received pentamidine. Failure to complete therapy was common. Of those receiving TMP-SMX, 39 (42%) required change in therapy because of failure to respond, and an additional 31 (34%) because of drug toxicity. This compared with 27 (40%; P = 0.733) and 17 (25%; P = 0.235), respectively, in the pentamidine-treated group. The overall survival rates were similar in the two groups, 62 out of 92 (67%) initially administered TMP-SMX versus 50 out of 68 (74%) initially administered pentamidine (P = 0.402). The survival rates for patients requiring a change in therapy because of failure to respond was 46% (18 out of 39) for the TMP-SMX group compared with 56% (15 out of 27) for the pentamidine group. When a change in therapy was made because of toxicity, survival rates were 97% (30 out of 31) for those receiving TMP-SMX versus 94% (16 out of 17) for those receiving pentamidine. CONCLUSION: TMP-SMX and pentamidine are of equivalent efficacy as initial therapies for PCP in patients with AIDS.  相似文献   
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It has been shown earlier that dilated cardiomyopathy can be associated withBorrelia burgdorferi infection.Here the authors present a case: a fifty-nine-year-old man who presented with dyspnea, oligoarthritis, paresthesia in both hands, and acrodermatitis chronica atrophicans. Upon further cardiologic exploration by cardiac catheterization and two-dimensional echocardiography (volume-length-area method), the patient exhibited an ejection fraction (EF) of 49%. Serology revealed IgG ELISA positive and IIFT 1:64 positive forB. burgdorferi. The patient received 2 × 150 mg roxithromycin orally for six weeks. Upon a second examination after termination of treatment (three months later), the patient presented with negativeB. burgdorferi serology and normal EF (70%). While cardiac manifestations thus apparently vanished, other symptoms persisted.This case may give new insight into mechanisms of action of macrolides againstB. burgdorferi (a field where information is inherently scant). One may, however, argue that in a well-perfused organ like the heart, tissue-activity of roxithromycin may suffice in order to unfold its activity againstB. burgdorferi.  相似文献   
108.
失控的炎性反应和补体活化参与多脏器功能衰竭的发病过程。而因肠粘膜屏障功能衰竭造成的大量肠道细菌和内毒素侵入体内协同作用形成的肠源性感染在多脏器功能衰竭发病中所起的作用又日益受到关注。本研究给动物注射一种补体活化和炎性反应的活化因子——酵母多糖,观察炎症和感染两者间的内在关联性。结果发现,亚致死量的酵母多糖(0.1mg/g)可损伤肠粘膜屏障而导致肠道细菌侵入体内。而蛋白质营养不良却显著强化了酵母多糖的上述病理效应,使动物形成致死性的全身性肠源性感染,感染的严重性和动物的病死率随营养不良的程度进行性增高。结果表明,在体内失控的炎性反应和肠源性感染有协同致病效应。  相似文献   
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OBJECTIVE: To compare perceived quality of life (QoL) in patients diagnosed with seasonal affective disorder (SAD) during the winter and summer months. METHODS: Twenty-six patients who were enrolled in an ongoing multicentre study in Canada completed 2 measures of QoL (the 20-item Medical Outcomes Study Short-Form General Health Survey [SF-20] and the Quality of Life Enjoyment and Satisfaction Questionnaire, [Q-LES-Q]) during the winter, when suffering from depression, and again during the summer months. RESULTS: Both general and health-related QoL scores were significantly improved in patients with SAD during the summer months, with scores for the most part falling within normal range. CONCLUSIONS: Perceived QoL in patients with SAD is markedly impaired during the winter months but shows a substantial rebound during the summer months. The findings of this study provide further evidence that SAD is a distinct diagnostic entity.  相似文献   
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