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41.
42.
Cutaneous manifestations of malignancy are not uncommon, especially in advanced disease. They may also occur early in malignant disease or they may even signify recurrence particularly if they are paraneoplastic in nature. Clinical diagnosis can be difficult because of the wide spectrum of appearance of these lesions, and, in many cases, because of the lack of an identifiable underlying primary. Presented here is the case of a 65-year-old woman with multiple inflammatory cutaneous metastases, which were sclerodermoid in nature. These appeared 14 months after initial diagnosis of adenocarcinoma of unknown primary (ACUP) and signified the beginning of a rapid deterioration in her condition. The coexistence of limited systemic sclerosis (scleroderma) and ACUP initially raised several interesting diagnostic possibilities. Adenocarcinoma of unknown primary and the sclerodermoid reaction in malignancy are discussed. 相似文献
43.
44.
Avram MJ Krejcie TC Niemann CU Enders-Klein C Shanks CA Henthorn TK 《Anesthesiology》2000,92(6):1757-1768
BACKGROUND: Earlier studies have demonstrated that physiologic marker blood concentrations in the first minutes after administration, when intravenous anesthetics exert their maximum effect, are determined by both cardiac output and its distribution. Given the reported vasodilating properties of isoflurane, we studied the effects of isoflurane anesthesia on marker disposition as another paradigm of altered cardiac output and regional blood flow distribution. METHODS: The dispositions of markers of intravascular space and blood flow (indocyanine green), extracellular space and free water diffusion (inulin), and total body water and tissue perfusion (antipyrine) were determined in four purpose-bred coonhounds. The dogs were studied while awake and while anesthetized with 1.7%, 2.6%, and 3.5% isoflurane (1.15, 1.7, and 2.3 minimum alveolar concentration, respectively) in a randomized order determined by a Latin square experimental design. Marker dispositions were described by recirculatory pharmacokinetic models based on very frequent early, and less frequent later, arterial blood samples. These models characterize the role of cardiac output and regional blood flow distribution on drug disposition. RESULTS: Isoflurane caused a significant and dose-dependent decrease in cardiac output. Antipyrine disposition was profoundly affected by isoflurane anesthesia, during which nondistributive blood flow was maintained despite decreases in cardiac output, and the balance between fast and slow tissue volumes and blood flows was altered. CONCLUSIONS: The isoflurane-induced changes in marker disposition were different than those the authors reported previously for halothane anesthesia, volume loading, or hypovolemia. These data provide further evidence that not only cardiac output but also its peripheral distribution affect early drug concentration history after rapid intravenous administration. 相似文献
45.
Zachary A Rodd Richard L Bell Ying Zhang James M Murphy Avram Goldstein Alejandro Zaffaroni Ting-Kai Li William J McBride 《Neuropsychopharmacology》2005,30(2):330-338
The meso-limbic dopamine (DA) system has an important role in regulating alcohol drinking. Previous findings from our laboratory indicated that Wistar rats self-administered ethanol (EtOH) directly into the posterior, but not anterior, ventral tegmental area (VTA), and that coadministration of a DA D(2,3) receptor agonist or a serotonin-3 (5-HT3) receptor antagonist blocked EtOH self-administration. In addition, we reported that alcohol-preferring (P) rats self-administered acetaldehyde (ACD), the first metabolite of EtOH, into the posterior VTA. The objectives of this study were to compare the reinforcing effects of EtOH and ACD within the VTA of P rats to examine the possibility that the reinforcing effects of EtOH within the VTA may be mediated by its conversion to ACD. Adult female P rats were stereotaxically implanted with guide cannulae aimed at either the posterior or anterior VTA. At 1 week after surgery, rats were placed in standard two-lever (active and inactive) experimental chambers for a total of seven to eight sessions. The 4-h sessions were conducted every other day. The results indicated that (a) 75-300 mg% (17-66 mM) EtOH and 6-90 microM ACD were self-administered into the posterior, but not anterior, VTA; (b) the self-administration of 150 mg% EtOH was not altered by coinfusion of a catalase inhibitor; (c) coadministration of the D(2/3) agonist quinpirole (100 microM) blocked the self-infusions of 150 mg% EtOH and 23 microM ACD into the posterior VTA; and (d) coadministration of 200 microM ICS205,930 (5-HT3 receptor antagonist) prevented the self-infusion of 150 mg% EtOH, whereas concentrations of ICS 205,930 up to 400 microM had no effect on the self-infusion of 23 microM ACD into the posterior VTA. Overall, the results of this study indicate that EtOH and ACD can independently produce reinforcing effects within the posterior VTA, and that activation of DA neurons mediates these effects. Furthermore, activation of 5-HT3 receptors within the posterior VTA is involved in the self-infusion of EtOH, but not ACD. 相似文献
46.
David P. Vogt Thomas Santoscoy Avram M. Cooperman Robert E. Hermann 《American journal of surgery》1983,146(2):274-279
The results of 157 operations performed for portal hypertension and esophageal varices on 148 patients at the Cleveland Clinic in the 10 year period between 1970 and 1980 are reported. One hundred four shunt procedures and 53 ligation procedures were performed. The overall operative mortality rate of 13 percent did not differ significantly from the 11 percent rate reported from this institution in 1971. A comparatively higher rate of recurrent variceal hemorrhage and a lower rate of encephalopathy reflected our increased use of selective shunts and ligation procedures. There was no improvement in overall long-term survival, which was approximately 50 percent.The two most important factors in predicting the results of all operations for esophageal varices continue to be assessment of preoperative liver function and the timing of the operation. The best results were obtained in patients with good liver function who had an elective operation. Our data suggest that the portacaval shunt is associated with a higher incidence of late mortality, largely as a result of liver failure; therefore, our preference now is to perform a distal selective splenorenal shunt procedure whenever possible. If a selective shunt procedure cannot be performed, we advocate either a mesocaval shunt or a ligation procedure, depending on patient risk and the suitability of veins for a shunt procedure. 相似文献
47.
Familial protein S deficiency with a variant protein S molecule in plasma and platelets 总被引:3,自引:0,他引:3
A protein S deficient family presenting a variant protein S molecule in plasma and platelets is described. The propositus, age 20, and two brothers suffered from venous thrombotic disease. The propositus, the only family member studied while taking oral anticoagulants, had a protein S antigen (ag) level of 17% and undetectable activity. As demonstrated by immunoblotting both the propositus and one clinically affected brother (42% ag, 7% activity) presented variant protein S molecules of 65,000 molecular weight (mol wt) while the other clinically affected brother (64% ag, 11% activity) had only protein S with normal electrophoretic mobility of 70,000 mol wt. The mother had normal protein S levels (93% ag, 100% activity) but had both normal and variant protein S molecules and based on her functional protein S data a normal anticoagulant activity of the variant molecule is suggested. One asymptomatic but protein S deficient sister (68% ag, 9% activity) as well as the asymptomatic protein S deficient father (59% ag, 10% activity) had only protein S molecules of 70,000 mol wt. The variant protein S bound to C4b-binding protein in plasma, and differed from normal protein S in carbohydrate content. Platelets of each family member contained the same immunoblotting pattern of normal and variant protein S forms as found in plasma, consistent with the hypothesis that protein S gene expression involves codominant expression of two alleles that is similar in cells that control the synthesis of both platelet and plasma forms of protein S. 相似文献
48.
Crosslinking the CD27 antigen on T cells provides a costimulatory signal that, in concert with T-cell receptor crosslinking, can induce T- cell proliferation and cellular immune activation. We find that chronic lymphocytic leukemia (CLL) B cells from most patients coexpress both membrane-bound and soluble CD27, along with its newly identified ligand, CD70. The expression of soluble CD27 may preclude leukemic B cells from stimulating T cells via CD70, thereby potentially impairing their ability to function as effective antigen-presenting cells. We find that leukemic B-cell expression of soluble and membrane-bound CD27 can be downmodulated through a CD40-dependent signal. This signal also induces enhanced expression of CD70 on both normal and leukemic B cells. We find that tumor necrosis factor (TNF)-alpha, or the Th1 cytokine interferon (IFN)-gamma, also can induce downmodulation of CD27, whereas Th2-associated cytokines interleukin-4 (IL-4) or IL-10 can enhance leukemic B-cell expression of this accessory molecule. The modulation of CD27 induced by these conditions is accompanied by reciprocal changes in the expression levels of CD70, suggesting that these accessory molecules may be engaged in reciprocal receptor-ligand downmodulation. Consistent with this, we observe that co-culture of CLL B cells with transfected murine plasmacytoma cells that express human CD70 affects downmodulation of CD27 and enhanced expression of CD70 on leukemic B cells, but does not affect expression of CD27 mRNA. However, we find that CD40-crosslinking, in addition to reducing the level of CD27 protein, also reduces leukemic B-cell expression of CD27 mRNA. This argues that the changes in the expression levels of CD27 following CD40-signaling are not simply due to induced increases in the expression levels of CD70. Finally, we demonstrate that reciprocal changes in expression of CD27 and CD70 may contribute to the enhanced antigen-presenting capacity of CLL B cells after CD40-dependent leukemic B-cell activation. These findings expand the understanding of the regulation of costimulatory molecules important in antigen presentation and also have implications for the immunobiology of and therapy for CLL. 相似文献
49.
Clonal dysregulation of the antibody response to tetanus-toxoid after bone marrow transplantation 总被引:2,自引:0,他引:2
Gerritsen EJ; Van Tol MJ; Van 't Veer MB; Wels JM; Khouw IM; Touw CR; Jol-Van Der Zijde CM; Hermans J; Rumke HC; Radl J 《Blood》1994,84(12):4374-4382
After bone marrow transplantation (BMT), a prolonged dysregulation of humoral immunity can be observed. In the present study, we investigated whether this is reflected in an abnormal production of specific antibodies (Ab) to the T-cell-dependent recall antigen tetanus-toxoid (TT). The study group consisted of children receiving transplants of an unmodified allogeneic graft and of adults receiving either a T-cell- depleted allogeneic or an unmodified autologous BM graft. Findings were compared with those in healthy controls. In pediatric graft recipients, who were routinely revaccinated early after BMT, the Ab response was quantitatively superior to that in adult graft recipients who did not receive early revaccination. In the majority of graft recipients, the time period after vaccination required to reach the peak level of antibodies was prolonged and the number of responding TT-specific B- cell clones was markedly decreased in comparison with controls. In controls, a low frequency of dominant B-cell clones may produce low quantities of homogeneous Ab components (H-Ab) against a heterogeneous background. However, in BM graft recipients, "overshooting" of Ab production by separate B-cell clones was observed, resulting in the development of H-Ab at a relatively high concentration. These abnormalities were present up to 10 years after BMT, irrespective of either the age of the recipient, the modulation of the graft, or the vaccination schedule used. It is hypothesized that the dysregulated Ab production is the consequence of activation of a restricted number of resting memory B cells, present in germinal centers, repopulating gradually after BMT. Our data show that routine revaccination early after BMT improves the humoral immune response. However, because of a clonally dysregulated Ab production, long-lasting qualitative defects may be present even after normalization of Ab titers. 相似文献
50.
Angiogenic factors stimulate mast-cell migration 总被引:18,自引:1,他引:18
Mast cells accumulate at sites of angiogenesis. The factor(s) that control mast-cell recruitment at these sites have yet to be defined. We sought to determine if angiogenic factors result in mast-cell chemotaxis. In this study, we observed that platelet-derived growth factor-AB (PDGF-AB), vascular endothelial cell growth factor (VEGF), and basic fibroblast growth factor (bFGF) each cause directed migration of murine mast cells at picomolar concentrations, with a typical bell- shaped dose-response curve. Another potent angiogenic factor, platelet- derived endothelial cell growth factor (PD-ECGF), appears to promote chemokinesis of mast cells, whereas tumor necrosis factor-alpha, a weak angiogenic factor, is less robust but still functions as a mast cell chemotactic factor. Epidermal growth factor (EGF), a growth factor with minimal angiogenic properties, was ineffective as a mast cell chemotactic factor. A checkerboard analysis confirmed the directional chemotactic response of PDGF-AB, VEGF, and bFGF, while indicating the chemokinetic response induced by PD-ECGF. Cross-desensitization of growth-factor-induced directed migration was observed between PDGF-AB and bFGF, and also between PDGF-AB and PD-ECGF. Tyrosine kinase- inhibitor genistein effectively dampened the chemotactic responses, whereas pertussis toxin had no effect. In summary, our findings suggest that factors known to act on endothelial cells and stimulate neovascularization may simultaneously serve to recruit mast cells to these sites. The local accumulation of mast cells is believed to facilitate new vessel formation through complex cell:cell interactions. 相似文献