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11.
Treatment for extensive-stage small cell lung cancer (ES SCLC) or extrapulmonary small cell carcinoma (EPSC) is typically palliative. We set out to determine progression-free survival (PFS) and overall long-term survival of ES SCLC and EPSC patients, physiologically aged < or = 60 years, responding to first-line chemotherapy followed by high-dose combination alkylating agents with hematologic stem cell support. Patients in first-line chemotherapy response underwent stem cell collection (marrow, peripheral blood progenitor cells, or both) followed by high-dose therapy with 1 of 2 regimens: CBP (cyclophosphamide, cisplatin, and carmustine) or ICE (ifosfamide, carboplatin, and etoposide) with or without etanidazole. Involved-field radiotherapy was given to selected patients with oligometastatic disease distributed in sites allowing for reasonable radiation ports, and prophylactic cranial radiotherapy was given upon recovery to patients in complete response (CR) or near-CR. A total of 36 patients were treated. Of 29 patients with ES SCLC, 6 (21%) had achieved CR, 18 near-CR, and 5 partial response prior to high-dose therapy. Of 7 patients with EPSC, 3 (43%) had achieved CR, 3 had achieved near-CR, and 1 had progression of disease prior to high-dose therapy. Thirteen ES SCLC patients received high-dose CBP. Of the remaining 23 patients with SCLC or EPSC, 17 were treated with ICE and 6 with ICE plus etanidazole, a hypoxic cell sensitizer. Treatment-related mortality was 11% (4 of 36 patients). For all patients, the median event-free survival (EFS) was 5 months. The 2- and 5-year survivals after intensification were 12% (95% confidence interval [CI], 5%-31%) and 9% (95% CI, 3%-27%), respectively. Of the 30 patients in or near CR prior to high-dose therapy, 5 remain continuously progression-free (2 ES SCLC, 3 EPSC) for a median of 55 months (range, 1-96 months) after high-dose therapy. By multivariate analysis, factors associated with more favorable EFS were the use of a more aggressive induction regimen (ICE), and the EPSC histology. These factors were also associated with more favorable overall survival. Other factors associated with more favorable overall survival were the use of short induction therapy (< or = 4 cycles) and younger age (<50 years). Except for high-dose ICE with etanidazole, the use of high-dose systemic therapy in ES SCLC and EPSC was associated with low treatment-related morbidity and mortality over the past 5 years. Late complications were infrequent, and most patients returned to full-time work and activity, barring disease recurrence. Nonetheless, few patients with ES SCLC have progression-free long-term survival. We conclude that high-dose therapy is not indicated as an approach for ES SCLC, except as part of an investigative trial. Conversely, 3 of the 7 patients with EPSC remain relapse-free (range, 1-96 months), warranting further phase II evaluation of this approach in this population.  相似文献   
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It was recently reported that the inheritance of the metacarpal cortical index (CI) in the Chuvashian population can be described in terms of a major gene (MG) model. By applying transmission probability tests, the hypothesis was accepted that not only baseline level of CI but also its sex‐specific dependence on age were under control of the same putative large‐effect gene. Using a pedigree sample from the population of the islands of Middle Dalmatia, Croatia (847 observed individuals in 278 pedigrees), data are presented to support the above findings. The following hypotheses were accepted: (i) inheritance of baseline CI in the Croatian population can be attributed to the effect of a MG responsible for about 42% of the variation; (ii) the same MG takes part in the control of the dependence of CI on age, particularly the age at onset of involutive bone changes (inflection point), and of the rate of decrease in CI with age (slope coefficient). Issues related to the assortative mating effect on CI and the determination of the most parsimonious model are discussed. Am. J. Hum. Biol. 13:398–408, 2001. © 2001 Wiley‐Liss, Inc.  相似文献   
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Group B streptococci (GBS) have been cultured from the chorioamnionic membrane of pregnant women, usually in association with chorioamnionitis and premature labor (K. A. Boggess, D. H. Watts, S. L. Hillier, M. A. Krohn, T. J. Benedetti, and D. A. Eschenbach, Obstet. Gynecol. 87:779–784, 1996). Colonization and infection of placental membranes can be a prelude to neonatal GBS infections even in the presence of intact membranes (R. L. Naeye and E. C. Peters, Pediatrics 61:171–177, 1978), suggesting that GBS cause chorioamnionitis or establish amniotic fluid infections by partial or complete penetration of the placental membranes. We have isolated and grown cultures of primary chorion and amnion cells from human cesarean-section placentas. This has provided a biologically relevant model for investigating GBS adherence to and invasion of the two epithelial barriers of the placental membrane. GBS adhered to chorion cell monolayers to a high degree. Pretreatment of GBS with trypsin reduced adherence up to 10-fold, which suggested that the bacterial ligand(s) was a protein. GBS invaded chorion cells at a high rate in vitro, and invasion was dependent on cellular actin polymerization. GBS could be seen within intracellular vacuoles of chorion cells by transmission electron microscopy. We also demonstrated that GBS were capable of transcytosing through intact chorion cell monolayers without disruption of intracellular junctions. GBS also adhered to amnion cells; in contrast, however, these bacteria failed to invade amnion cells under a variety of assay conditions. GBS interactions with the chorion epithelial cell layer shown here correlate well with epidemiological and pathological studies of GBS chorioamnionitis. Our data also suggest that the amnion cell layer may provide an effective barrier against infection of the amniotic fluid.  相似文献   
15.
Summary 1. Action-concentration curves have been plotted for the stimulation of the cat's superior cervical ganglion by acetylcholine. The free and the innervated receptors of the postsynaptic membrane, described by the authors, have been studied separately from this point of view.2. In the case of both the free and the innervated receptors, the action-concentration curves were similar in shape to the enzyme-substrate curve of cholinesterase. Analyzing these curves by the method of Lineweaver and Burk, in the case of free receptors, the dissociation constants of acetylcholine turned out to be: with stimulating RS complexes: 5.4·10–6–2.1·10–5M, with inhibitory RS 2 complexes: 3.2·10–5 – 5.2·10–5 M. The pertaining values for innervated receptors were 3.45 · 10–5 and 2.22 · 10–4 M, respectively.3. The parallelisms and divergences between the cholinesterase and acetylcholine-receptor functions are discussed.With 4 Figures in the Text  相似文献   
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A dihydropyridine pyridinium salt redox carrier-based chemical delivery system for benzylpenicillin (1) was complexed with 2-hydroxypropyl--cyclodextrin (HPCD). The solubility of the lipophilic 1, which is incompatible with aqueous formulations, was dramatically increased and showed a linear dependency on the HPCD concentration. The degree of incorporation was 20 mg of 1 per g of complex. The stability study of 1 in various pH buffers indicated the base-catalyzed hydrolysis of the acyloxyalkyl linkage and the hydration of the 5,6 double bond of the dihydropyridine as the main degradation processes. The overall loss of 1, which follows first-order kinetics, was not influenced by changes in ionic strength and elimination of oxygen from the reaction medium. The HPCD complex of 1, which has a stability constant of 720–940 M –1, stabilized the chemical delivery system. The influence of the temperature on the stability of 1 is also discussed.  相似文献   
18.
Summary Cyclophosphamide demonstrates enhanced tumoricidal activity with decreased bone marrow toxicity when given on a divided-dose schedule in certain animal models. A total of 22 patients presenting with refractory metastatic cancer were treated in a phase I trial of continuous infusion of cyclophosphamide over 96 h. Granulocytopenia of <500/l that lasted for > 14 days or thrombocytopenia of <25,000/l that lasted for > 14 days was the target dose-limiting toxicity in the absence of nonhematologic grade 4 toxicity. The maximal tolerated dose was 7 g/m2. Three patients died. Of 21 evaluable patients, 9 responded, including 8/9 who had experienced disease progression during prior oxazaphosphorine-containing combination chemotherapy. Clinically meaningful responses were observed in patients who had demonstrated clinical resistance to an oxazaphosphorine drug given at lower doses.Supported in part by U.S. Public Health Service grant P01CA-38493 and by a grant from the Mather's Foundation. Two of the authors (J. P. E. and A. D. E.) are recipients of Career Development awards from the American Cancer Society, and one (T. C. S.) is a recipient of a Faculty Development Award from the Pharmaceutical Manufacturer's Association Foundation  相似文献   
19.
Organ-specific acellular matrix for reconstruction of the urinary tract   总被引:5,自引:0,他引:5  
In urology, replacement of organs or organ segments has proved problematic. Current techniques do not replicate complete organ function, and they cause well-known complications. With the acellular organ-specific matrix we have found a way to regenerate tissue components seen in the normal lower urinary tract. The time required for regeneration depends on the matrix size and function. The matrix is covered by urothelium migrating from the host, after which neovascularization occurs, followed by formation of smooth-muscle cells and nerves. In our studies, normal muscle lining and nerves providing functional tissue were demonstrable and no sign of antigenicity was evident, even after heterologous grafting. The regenerated rat bladder was evaluated by organ bath as well as by in vivo functional tests and demonstrated properties and functions similar to those of host tissue. Besides our obtaining encouraging results in the rat bladder, we also studied the organ-specific acellular matrix in other species (dog and rabbit) and other organ segments (ureter and urethra).  相似文献   
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