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A modified technique for palliative resections of malignant endobronchial tumors with the Nd:YAG laser is described. A special tracheoscope was used in conjunction with the instrument guide of a laser bronchoscope. The main advantage of this technique is easy and simultaneous access to both lungs for ventilation and surgical procedures. The method helps to separate surgical from anesthetic manipulations. The experience of over 70 operations using this technique provides evidence that the use of a tracheoscope is a safe and efficient method of endoscopic resections of larger intrabronchial tumors.  相似文献   
3.
Recent protocols have allowed successful positive crossmatch (+XM) and ABO incompatible (ABOI) kidney transplantation, although their long-term outcome is not clear. To begin to assess this issue we compared protocol biopsies performed 12 months posttransplant in 37 +XM, 24 ABOI and 198 conventional allografts. Although the majority in all three groups had only minimal histologic changes, transplant glomerulopathy (TG) was significantly increased in +XM (22% vs. 13% ABOI vs. 8% conventional, p = 0.015), and correlated with prior humoral rejection (HR) by multivariate analysis (odds ratio 17.5, p < or = 0.0001). Patients with a prior history of HR also had a significant increase in interstitial fibrosis (No HR 54% vs. HR 86%, p = 0.045). In the absence of HR no difference in histologic changes was seen between groups, although all three groups had a demonstrable mild increase in interstitial fibrosis from biopsies performed at the time of transplant. Thus, although HR is associated with an increase in TG, in its absence allograft histology is similar in +XM, ABOI and conventional allografts 1 year posttransplant.  相似文献   
4.
Sixty Sprague-Dawley rats were pair-fed one of three nutritionally identical diets. One diet contained “low-fiber” (3.8% crude fiber); the others contained “high fiber” (28.7% crude fiber) composed of either cellulose or lignin. Although both “high fiber” diets had similar stool bulking effects, only the cellulose diet was associated with a reduction in 1,2-dimethylhydrazine (DMH)-induced colon neoplasms. The cellulose diet was also associated with distinct changes in the gut bacterial profile and with a lowered serum cholesterol. © 1993 Wiley-Liss, Inc.  相似文献   
5.
It has been demonstrated, that in a regular mastectomy a certain amount of glandular tissue is left back in the overlying skin flaps. If direct skin closure is achieved postoperatively, the glandular tissue remnants are laid with the skin flaps on top of the denuded pectoral muscle. Since these glandular tissue remnants may contain or develop breast cancer, a latter recurrence on the thoracic wall may take place. In order to avoid these iatrogenic thoracic wall recurrences an interpositioning of vital tissues between the thoracic wall and the skin is recommended. This is achieved by reconstructing the breast immediately after mastectomy.  相似文献   
6.
A case of unexpected cardiac arrest occurring in a 17-year-old male patient is reported. The patient had been admitted after sustaining hand trauma. A first emergency surgical procedure was carried out, followed about three weeks later by another one. No incidents occurred during or after either of these two operations. A third procedure was required about two months after the accident (free toe graft to the thumb of the left hand). The twelve-hour operation was carried out under general anaesthesia and axillary block. The patient was given intravenous heparin (800 IU.h-1) during the procedure on the arm. The patient recovered quickly, and was extubated before his transfer to the recovery room. Fifteen minutes later, the patient's heart rate decreased to 40 b.min-1, followed by a transient cardiorespiratory arrest. The suspicion of pulmonary embolism was confirmed by pulmonary scintigraphy. Thrombolysis was carried out with 2,000 IU.kg-1.h-1 of urokinase for a 72 h period, combined with continuous heparin administration (16 to 36 x 10(3) IU.day-1). The patient recovered after one week. No thrombophlebitis was found for origin of the emboli. Biological investigations carried out both before and after 10 minutes of anoxia revealed a normal fibrinolytic system, but a deficit in protein C (62% antigen, 64% activity). Two years after the episode of pulmonary embolism, the patient, still taking acenocoumarol, remained free from any sequela. Current perioperative management of patients with a known protein C deficit is discussed.  相似文献   
7.
To assess the incidence rate and the characteristics of traveler's diarrhea in small children ages 0 to 2 years, children ages 3 to 14 years, and adolescents ages 15 to 20 years a retrospective survey was conducted. Of the pretravel visitors to the Zurich University Vaccination Center, all those ages 0 to 20 years were selected between October, 1987, and May, 1988. They received a questionnaire within 2 weeks after returning home. Of the 446 young travelers who were recruited, 363 (81.3%) could be evaluated. Within 14 days in the tropics or subtropics, traveler's diarrhea occurred in 8 of 20 (40.0%) small children, in 4 of 47 (8.5%) children ages 3 to 6 years, in 10 of 46 (21.7%) children ages 7 to 14 years and in 90 of 250 (36.0%) adolescents (P = 0.0003). In small children the clinical course tended to be severe and prolonged (average duration, 29.5; median, 17.5 days) when compared with other age groups (3 to 5 days). In 40% of all the children the parents reported that they had consistently practiced dietary preventive measures. For self-treatment oral rehydration solutions were used in 5.0% and loperamide in 33.8%. In conclusion adults should be discouraged from taking small children to developing countries unless necessary. Parents should be instructed about how to prevent traveler's diarrhea and about the mainstay of self-therapy in pediatric patients by oral rehydration solutions.  相似文献   
8.
9.
Psoriasis vulgaris, a type-1 cytokine-mediated chronic skin disease, can be treated successfully with fumaric acid esters (FAE). Beneficial effects of this medication coincided with decreased production of IFN-gamma. Since dendritic cells (DC) regulate the differentiation of T helper (Th) cells, this study focussed on effects of monomethylfumarate (MMF, bioactive metabolite of FAE) on polarization of monocyte-derived DC. MMF-incubated, lipo-polysaccharide-stimulated DC (MMF-DC) produced dramatically (p<0.05) reduced levels of IL-12p70 and IL-10 (8+/-4% and 20+/-4%, respectively) compared to control DC. MMF-DC were mature. MMF affected polarization of DC irrespective of polarization factor(s) and ligands for the various Toll-like receptors used. Coculture of MMF-DC with naive and primed allogenous Th cells resulted in lymphocytes producing less IFN-gamma, i.e. 59% and 54% of that by the respective Th cells cocultured with control DC. IL-4 production by primed, but not naive Th cells cocultured with MMF-DC was decreased as compared to cocultures with control DC. IL-10 production by naive and primed Th cells cocultured with MMF-DC and control DC did not differ. In addition, MMF inhibited LPS-induced NF-kappaB activation in DC. Together, beneficial effects of FAE in psoriasis involve modulation of DC polarization by MMF such that these cells down-regulate IFN-gamma production by Th cells.  相似文献   
10.
Serum and tissue lysozyme in leprosy.   总被引:3,自引:2,他引:3       下载免费PDF全文
Mean serum lysozyme values were found to be elevated in untreated leprosy patients. Statistically significant elevations were present in each of the three major categories of leprosy, tuberculoid, borderline, and lepromatous. Values were particularly high in patients with severe reversal reactions or Lucio's phenomenon. Prolonged sulfone therapy was associated with a fall in serum lysozyme values. With an immunoperoxidase method to localize lysozyme in leprous tissues, two distinct staining patterns were found, granular and saccular. The grandular pattern of lysozymal staining was found in epithelioid cells and in giant cells, and the intensity of staining showed a positive correlation with serum lysozyme levels. Conversely, a saccular pattern of lysozymal staining was found in lepromatous histiocytes, buth the intensity of staining was unrelated to serum lysozyme levels; the saccular structures contained dense aggregates of Mycobacterium leprae. These two patterns of staining probably represent different functional responses of monocyte-derived granuloma cells, whereas the serum levels reflect, to a varying degree, both the absolute number of such cells and the rate of secretory activity of this cell population as a whole.  相似文献   
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