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121.
The pharmacokinetics and metabolism of 4-demethoxydaunorubicin (idarubicin, IDA) were studied in 21 patients with advanced cancer after i.v. (12 mg/m2) and oral (30-35 mg/m2) treatment according to a balanced crossover design. Patients were divided into four groups: subjects who showed normal liver and kidney function (group N), those who presented with normal kidney function and liver metastases (group L), those with kidney dysfunction (creatinine clearance, less than or equal to 60 l/h; group R), and those with both liver and kidney dysfunction (group LR). Five patients showed variations in liver or kidney function after the first treatment and were considered to be nonevaluable for the crossover study but evaluable for the liver/kidney function study; some of them appeared in different groups for the i.v. as opposed to p.o. treatments. After i.v. administration, IDA plasma levels followed a triphasic decay pattern. The main metabolite observed in all patients was the 13C-reduced compound (IDAol), which attained plasma levels 2-12 times higher than those of the parent compound. IDA pharmacokinetics was not dependent on the presence of liver metastases but was related to the integrity of kidney function. Analysis of variance indicated a significant correlation between IDA plasma clearance and creatinine clearance; it was also found that IDA plasma clearance was lower in patients whose creatinine clearance was less than 60 ml/min [group N, 122.8 +/- 44.0 l/h; group L, 104.4 +/- 27.7 l/h (P = 0.58) vs group R, 83.4 +/- 18.3 l/h (P = 0.037)]. The IDAol terminal half-life and mean residence time (MRT) were significantly increased in patients with impaired kidney function [MRT: group N, 63.6 +/- 10.8 h; group L, 69.9 +/- 10.2 h (P = 0.27) vs group R, 83.2 +/- 10.9 h (P = 0.025) and t1/2 gamma: group N, 41.3 +/- 10.1 h; group L, 47.0 +/- 7.4 h (P = 0.31) vs group R, 55.8 +/- 8.2 h (P = 0.025)]. After oral treatment, drug absorption occurred during in the first 2-4 h after IDA administration; a biphasic decay pattern was observed thereafter. The main metabolite observed in all patients was again IDAol. The AUC of IDAol was greater after oral administration than after i.v. treatment in proportion to the AUC of IDA (i.v.: AUC-IDAol/AUC-IDA, 2.4-18.9; p.o.: AUC-IDAol/AUC-IDA, 4.1-21.4). Following oral dosing, a substantial amount of 4-demethoxydaunomycinone (AG1) was found in 11/21 patients.(ABSTRACT TRUNCATED AT 400 WORDS)  相似文献   
122.
The objective of this study was to find the incidence of accidental exposures to blood and body fluids among surgeons during operations and to describe their dynamics. A probabilistic model was also used to predict the cumulative 30-year risk to the surgeon of contracting hepatitis B and C viruses (HBV, HCV) or human immunodeficiency virus (HIV) infection and estimate the effect of preventive strategies in reducing this risk. A multicentric prospective survey, based on self-administered questionnaires, was conducted during a period of 6 months in 39 Italian hospitals. An accidental exposure to blood or body fluids occurred in 9.2% of 15,375 operations. In about 2% of procedures a parenteral-type injury, such as actual skin puncture or eye contamination, was suffered by the operating surgeon. A needle-stick injury was the commonest accident, and its occurrence was found to vary with the phase of the procedure and its length. The current lifetime risk of acquiring HBV, HCV, and HIV infection in our regions was estimated to be as high as 42.7%, 34.8%, and 0.54%, respectively. The adoption of preventive strategies is expected to reduce this risk to 21% for HBV, 16.6% for HCV, and 0.23% for HIV infection. Active immunization of surgeons against HBV is strongly recommended. The case is also made for the use of a face-shield combined with a permanent change in our surgical practice capable of reducing the current high rate of parenteral injuries.  相似文献   
123.
The Physical Capacity Evaluation, a performance measure of functional capabilities comprised of 13 tasks simulating those used in activities of daily living, was tested on 289 community-dwelling elderly people and compared against a widely used self-report measure of function, the Health Assessment Questionnaire. Factor analysis identified one dominant component in each instrument. Internal consistency reliability (Cronbach's alpha) was .90 for both instruments. Global disability (Health Assessment Questionnaire) and function (Physical Capacity Evaluation) scores were correlated -.74. One-week retest reliabilities on 58 subjects were .94 for the Physical Capacity Evaluation and .95 for the Health Assessment Questionnaire. The Physical Capacity Evaluation is a valid and reliable measure of physical performance for use with elderly people.  相似文献   
124.
Micrografting in the treatment of severely burned patients   总被引:4,自引:0,他引:4  
The micrografting technique, employed to treat patients with extensive TBSA burns and reduced areas of healthy donor skin, was assessed simultaneously with traditional mesh grafts (STSG) or Tiersch grafts in the treatment five severely burned subjects (average TBSA burned 35.6 per cent; average per cent of full thickness wounds 32.6 per cent).

At the first clinical control on day 6 post-surgery 93 per cent of the micrografted area was in situ and healthy: epithelialization of the wound sites was complete at day 21. Meshed STSG yielded 90 per cent attachment at day 6 post-surgery, with epithelialization complete at 12 ± 2 days post-surgery.

Functional results were equivalent no matter what technique was used, while aesthetic results were better in the areas where micrografting was carried out.

Although the micrograft technique is labour-intensive, if the expansion needed is at least 1:6, the aesthetic and functional results obtained are comparable to, or better than, those with meshed grafts. Also, large segments of micrograft are not compromised if a small area of mesh becomes detached, and epithelialization is faster and more uniform, enabling a reduction in both infection and length of hospital stay.  相似文献   

125.
The purpose of this study was threefold: to evaluate the role of gallium-67 scintigraphy in the staging of low-grade non-Hodgkin’s lymphomas (LGNHL), to assess the relationship between the expression of CD71 on the surface of the neoplastic cells and the 67Ga uptake by the tumour, and to establish the contribution of 67Ga scan in defining the prognosis of LGNHL. Forty-eight patients with untreated LGNHL diagnosed in a single institution over a decade were reviewed. The end point of the study was survival of the patients according to the scintigraphic 67Ga score at diagnosis. In addition to 67Ga scan, other prognostic variables were studied, relating to the neoplastic burden, the biology of the tumour and the host. Univariate and multivariate analyses were used. 67Ga scan identified only 116/286 (41%) nodes involved by lymphoma that were detected by clinical examination or computed tomography scan. A scintigraphic scoring system with an arbitrary cut-off value of 3 (high scan score) was able to predict patients with a dismal prognosis: with a mean follow-up of 47 months (range: 1–146 months) the median survival time was 28 months in patients with a high scan score and 74 months in patients with a low scan score (P=0.002). CD71 values were 27.4%±14.9% (mean ±SD) in the former and 8.9%±7.2% in the latter (P=0.0001). Only performance status and extranodal sites were significant variables for prognosis in multivariate analysis. It is concluded that 67Ga scan is inaccurate in staging but might be very important in defining the prognosis in LGNHL, in association with other prognostic variables. Received 1 May and in revised form 6 August 1997  相似文献   
126.
127.
Lymph node (LN) metastases represent the most important negative prognostic factor in squamous cell carcinoma (SCC) of the oral cavity, even though controversies still exist regarding their management. The aim of this study was to retrospectively analyze our experience in surgical management of SCC of the oral cavity with particular focus on the prevalence and localization of lymph nodal metastases and recurrences. The clinical records of 89 consecutive patients treated from 1983 to 2002 by concomitant surgery on both the T and N sites, excluding those undergoing salvage surgery, were reviewed. A total of 119 neck dissections (ND) were performed. Survival outcomes were calculated by the Kaplan–Meier method, while univariate comparisons by the log-rank and non-parametric tests were performed between different groups of patients. Five-year overall and determinate survivals were 50 and 57%, respectively. LN metastases were observed in 52% (56% of these showing extracapsular spread) and their presence strongly correlated with determinate survival (p < 0.0001). The prevalence of clinical and occult nodal disease was not related to the pT status. Neck levels II (59%) and I (56%) were most frequently involved. Metastases to level IV accounted for 15% of positive LN, even though 28% of them turned out to be skip metastases. Five neck recurrences were observed, only one of which was salvaged by surgery. The high prevalence of clinical and occult LN metastases in this setting suggests that ND should be performed on a nearly routine basis, even for lesions with a low-T category and a cN0 neck. Moreover, ND should always encompass level IV due to the possibility of skip metastases, particularly in tumors involving the oral tongue. In patients with a cN+ neck, levels from I to V should be addressed, particularly in the presence of metastases at levels III and IV.  相似文献   
128.
Rewarming and cardiac surgery: a review   总被引:1,自引:0,他引:1  
Patients undergoing cardiac surgery are mildly hypothermic by the completion of the surgical procedure. They need to return to a normothermic state if enzymatic functions are to proceed in their normal manner. The body can produce heat by elevating metabolic rate or by activating the shivering mechanism. Metabolic rate peaks shortly after separation of the patient from cardiopulmonary bypass, and therefore contributes to heat production. Because of the effects of neuromuscular blockage administered both during and after surgery; these patients may be unable to generate heat by shivering, and shivering is usually undesirable. This eliminates the major heat production mechanism available to the body. Therefore, heat must be transferred down its gradient by means of convection and conduction. External and internal methods accomplish these goals. External methods, which minimize additional heat loss, include the use of warming lights, elevation of room temperature, and the use of blankets. Internal methods, which transfer heat by convection, may be used to help actively reverse hypothermia. Such techniques include warmed inhalation gases and intravenous fluids, warmed nasogastric lavage fluid, and warmed peritoneal dialysis fluid for patients with end-stage renal failure with severe electrolyte disorders after surgery.  相似文献   
129.
130.
Introduction There is now increasing evidence that proximal tubular cells (PTCs) contribute to renal interstitial fibrosis by alteration of matrix turnover and by the generation of pro‐fibrotic cytokines such as TGF‐β1. Recent studies suggest that, through a process of transdifferentiation, the PTCs are one source of the interstitial myofibroblasts that directly drive the fibrotic process. The aim of this work was to examine the role and mechanism by which TGF‐β1 may regulate PTC phenotype and function. Methods Experiments were performed using both primary‐cultures of PTC and the human PTC cell line HK2. All experiments were performed on growth‐arrested cells in the absence of serum. Results TGF‐β1 altered cell phenotype, assessed by light microscopy, with cells appearing elongated and spindle‐shaped. This was associated with loss of cell–cell contact and rearrangement of the actin cytoskeleton, increased formation of stress fibres and focal adhesions. Disruption of the actin cytoskeleton with cytochalasin‐D prevented phenotypic alterations following addition of TGF‐β1. Transient transfection with Smad‐2/‐4 or Smad‐3/‐4 expression vectors did not alter cell phenotype. Previously, we have demonstrated β‐catenin translocation to PTC nuclei and its association with Smad proteins following addition of TGF‐β1, suggesting the possibility that TGF‐β1 may modulate Wnt signalling. Wnt‐responsive Xtwn‐reporter construct was, however, silent in response to TGF‐β1. Similarly, a second Wnt‐/LEF‐1‐regulated element Toplflash, which does not contain Smad‐binding sites, was insensitive to TGF‐β1 signalling. In contrast, phenotypic changes in response to TGF‐β1 were abrogated by inhibitors of the RhoA downstream target ROCK, which also prevented loss of cell–cell contact and adherens junction disassembly. Removal of TGF‐β1 and addition of 1% FCS, however, reverted cell phenotype to a typical cobblestone epitheliod appearance, suggesting that TGF‐β1 did not result in terminal PTC transdifferentiation. Cells grown on tissue culture dishes coated with either type‐I or type‐III collagen also acquired an elongated fibroblastic phenotype; this effect was exaggerated by the addition of TGF‐β1. In contrast to the cells stimulated with TGF‐β1 alone, following stimulation by both TGF‐β1 and exposure to interstitial collagens, cell phenotype was stable in that it was not reversed upon removal of TGF‐β1 and addition of FCS. Addition of TGF‐β1 to cells grown on type‐IV collagen had no greater effect than TGF‐β1 alone. Addition of TGF‐β1 alone had little effect on the expression of α‐SMA. In contrast, cells grown on either type‐I or type‐III collagen, following addition of TGF‐β1, demonstrated marked increased expression of α‐SMA, which appeared to be incorporated into the cell cytoskeleton. Similarly, the combination of interstitial collagen (either type‐I or type‐III) and TGF‐β1 had synergistic effect on the relocation and down‐regulation of the epithelial markers E‐cadherin and cytokeratin. Finally, the results demonstrated synergistic effects of coating with interstitial collagen (either type‐I or type‐III), on cell ‘fibroblastic’ cell function as assessed by cell migration and by the synthesis of type‐III and type‐IV collagen. Conclusion The results of these in vitro experiments suggest that terminal transdifferentiation of proximal tubular epithelial cells is the result of a combination of the effects of the pro‐fibrotic cytokine TGF‐β1 and exposure of the cells to components of the interstitial extra‐cellular matrix to which the cells are not exposed in the absence of damage to the tubular basement membrane.  相似文献   
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