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71.
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From January 1981 through October 1995, a total of 28 patients underwent surgery for metastatic lung tumors in our institute. A retrospective review and survival analysis of these patients are reported. There were 12 males and 16 females, with the mean age of 57 years. Of them, 20 patients had solitary lesions. Pulmonary metastasis was from the colon in 8 patients, from the breast in 5, from the stomach and the uterus in each 3, from the bladder, the rectum and the soft tissue in each 2, and from the kidney, the ovarium and the thyroid in each 1. A lobectomy was performed in 22 patients, 17 of whom were accompanied with mediastinal lymph node dissection (R2a). Partial resection without lymph node dissection was performed in 6 patients (R0). Overall 5-year survival was 24.7%. Four-year or over survivor were 4 patients who underwent a lobectomy with R2a. The patients undergoing lobectomy had a significantly better prognosis compared with patients with partial resection (p<0. 05). The patients with R2a had significantly less local recurrence than patients with R1 or R0 (p<0.05). We conclude that lobectomy with R2a is suitable treatment for metastatic lung cancer.  相似文献   
73.
BACKGROUND: Heart transplantation (HT) as a therapeutic option for end-stage chronic Chagas' heart disease (CCHD) is controversial. Reactivation of Trypanosoma cruzi infection and recurrence of the disease in the allograft are likely to occur. Furthermore, active myocarditis has been reported to predispose patients to an increased incidence and severity of rejection. METHODS AND RESULTS: We prospectively investigated the long-term follow-up of 10 patients with CCHD who underwent HT. Immunosuppression was based on cyclosporine A and azathioprine. T cruzi reactivation was prevented with benzonidazole. Besides allograft rejection surveillance, T cruzi infection was monitored through blood tests, myocardial biopsies, and serological tests. Over a mean follow-up period of 34 +/- 38 months (range, 73 to 124 months), 7 patients are alive and in NYHA functional class I. Life expectancy was 78% for the second year and 65% for 10 years. Rejection was less frequent in chagasic than in age- and sex-matched control patients (mean +/- SD, 1.60 +/- 1.26 versus 5.70 +/- 1.89 episodes per patient, respectively; P = .0001); decreased severity of rejection was also observed (P = .006). T cruzi parasitemias detected on three occasions were successfully treated with benzonidazole. There were no signs of recurrence of the disease in the allograft. CONCLUSIONS: These results suggest an important role of HT in the treatment of CCHD. There was a low frequency of T cruzi infection reactivation and no signs of recurrence of the disease in the allograft. The surprisingly decreased rejection incidence and severity require further studies for elucidation.  相似文献   
74.
Multiple biologic effects of interferon-alpha (IFN-alpha), including cell growth inhibition and antiviral protection, are initiated by tyrosine phosphorylation of STAT proteins. Although this signal pathway has been intensively investigated, the relevance of STAT signal persistence has received scant attention. Using paired isogenic lymphoma cells (Daudi), which either are sensitive or resistant to growth inhibition by IFN-alpha, we found comparable initial tyrosine phosphorylation of multiple STAT proteins; however, the phosphorylation durations and associated DNA-binding activities diverged. Phosphorylation and DNA-binding capacity of STAT1 decreased after 4 to 8 hours in resistant cells, as compared with 24 to 32 hours in sensitive cells, whereas phosphorylation of STAT3 and STAT5b was briefer in both lines. Functional significance of the prolonged STAT1 signal, therefore, was explored by experimental interruption of tyrosine phosphorylation, either by premature withdrawal of the IFN-alpha or deferred addition of pharmacologically diverse antagonists: staurosporine (protein kinase inhibitor), phorbol 12-myristate 13-acetate (growth promoter), or aurintricarboxylic acid (ligand competitor). Results indicated that an approximately 18-hour period of continued STAT1 phosphorylation was associated with growth arrest, but that antiviral protection developed earlier. These differences provide novel evidence of a temporal dimension to IFN-alpha signal specificity and show that duration of STAT1 activation may be a critical variable in malignant cell responsiveness to antiproliferative therapy.  相似文献   
75.
To clarify the characteristic features of nosocomial pneumonia in a community hospital, we performed a clinical analysis of 147 patients (155 episodes) with nosocomial pneumonia. The following results were obtained. 1, Regarding the risk factors for nosocomial pneumonia, factors such as the patient whose age was over 65 years, a duration of admission of over one month, performance status 4 and underlying respiratory diseases associated with the appearance of nosocomial pneumonia. 2, The causative microorganism isolated from the sputum of the patient with nosocomial pneumonia was frequently a multi-drug resistant microorganism such as Methicillin-resistant Staphylococcus aureus (MRSA). 3, regarding treatment, although several antibiotics were administered for a long time, mechanical ventilation was used on 31% of the patients, and steroid pulse therapy was carried out on 24%. The clinical efficacy was poor with a 50% mortality rate. The reason why treatment of nosocomial pneumonia was difficult is thought to be been related to the general condition of these inpatients and to the appearance of a multi-drug resistant, polymicrobial microorganisms.  相似文献   
76.
The ability of the second generation phosphodiesterase 4 inhibitor SB 207499 (Ariflo), [c-4-cyano-4-(3-cyclopentyloxy-4-methoxyphenyl)-r-l-cyclohexane carboxylic acid], to inhibit inflammatory cytokine production in vivo was evaluated and compared to that of rolipram, a first generation phosphodiesterase 4 inhibitor. To examine human tumor necrosis factor alpha (TNFalpha) production, human monocytes were adoptively transferred into Balb/c mice and challenged with lipopolysaccharide (LPS). In this model, SB 207499 inhibited human TNFalpha production with oral ED50 of 4.9 mg/kg. Similarly, R-rolipram inhibited human TNFalpha production with an ED50 of 5.1 mg/kg, p.o. In contrast to their equipotent activity against TNFalpha production, SB 207499 (ED50 = 2.3 mg/kg, p.o.) was 10-fold less potent than R-rolipram (ED50 = 0.23 mg/kg, p.o.) in reversing reserpine-induced hypothermia, a model of antidepressant activity. In time course studies, SB 207499 (30 mg/kg, p.o.) inhibited TNFalpha production for at least 10 hr; substantial plasma concentrations of SB 207499 were detected over the same interval. The ability of SB 207499 to modulate interleukin-4 production in vivo was assessed in a chronic oxazolone-induced contact sensitivity model in Balb/c mice. In this model, topical administration of SB 207499 (1000 microgram) inhibited intralesional concentrations of interleukin-4 (55%; P <.01). The results demonstrate that SB 207499 is a potent inhibitor of inflammatory cytokine production in a variety of settings in vivo. Moreover, although it is as potent as R-rolipram in inhibiting TNFalpha production, it has substantially less central nervous system activity. Thus SB 207499 represents an excellent candidate with which to evaluate the antiinflammatory potential of PDE4 inhibitors.  相似文献   
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Peptides labelled with the fluorophore cyanine 3 were used to study naturally expressed neuropeptide receptors by confocal microscopy in continuous cell lines, primary cultures, and unfixed tissue. Swiss 3T3 fibroblasts bound cyanine 3-gastrin-releasing peptide at 4 degrees C, and internalized the peptide after 10 min at 37 degrees C. Internalization was specific, since it was blocked by incubation with unlabelled peptide. Primary cultures of myenteric neurons of the guinea pig incubated with cyanine 3-substance P at 4 degrees C had specific surface labelling. After 30 s at 37 degrees C, the peptide was internalized into vesicles in both the soma and neurites. Direct observation of live neurons showed movement of fluorescent vesicles to a perinuclear region after 30 min. Endocytosis was associated with a loss of surface binding sites. Unfixed whole mounts of guinea pig and rat ileum were incubated with cyanine 3-neurokinin A at 4 degrees C. After 5 min at 37 degrees C, Cy3-neurokinin A was specifically internalized in neurons and smooth muscle cells. After 30 min, a perinuclear labelling occurred in some cells. Labelling in rat neurons was diminished by the NK3-R antagonist SR142801. Thus, cyanine 3-neuropeptides are valuable tools to study expression and endocytosis of naturally expressed receptors.  相似文献   
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80.
To assess the mechanisms related to tetanus-induced acute renal failure (ARF), 30 patients with tetanus had their renal function prospectively studied and factors possibly related to renal changes were evaluated during four weeks of hospitalization. Fifty percent of these patients had a glomerular filtration rate (GFR) < or = 50 ml/min in the first or second week of hospitalization (Group I) and 50% had a GFR > 50 ml/min throughout the entire hospitalization period (Group II). Age, gender, tetanus incubation time and tetanus onset time, hospitalization time, use of nephrotoxic drugs, need for mechanical ventilation with intermittent positive pressure, and presence of systemic infection were similar in both groups. None of the patients presented with oliguria. Autonomic nervous system (ANS) overactivity, characterized by intense variations in systolic and diastolic blood pressure, by increased heart rate and elevated urinary metanephrine excretion, was higher in Group I compared with Group II. Plasma renin activity, serum creatinephosphokinase levels, and myoglobinuria were not significantly different between the two groups. These results strongly suggest that tetanus-induced ARF has a high prevalence, is characterized by early onset, and is probably related to ANS overactivity.  相似文献   
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