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991.
The value of urine flow cytometry (UFC) in diagnosing acute renal allograft rejection (AR) was recently established in a prospective double-blind study. In this study, we report the 1-year follow-up of three groups of patients identified during the previous study: group 1--stable patients (no ARs) with persistently negative UFCs (n=7); group II--patients who had early ARs (<3 months after transplantation), with positive UFCs that completely normalized with antirejection therapy (n=8); group III--stable patients (no ARs) with positive UFCs (n=7). By definition, group III consists of patients previously considered to have "false positive" UFCs. All patients received standard immunosuppressive therapy, with regimens that included cyclosporine at doses adjusted to maintain target levels. Serum creatinine (SCr) levels (mg/dl) were similar in all three groups at 1 month after transplantation. However, at 1 year after transplantation, SCr was 1.4 +/- 0.2 in group I, 2.0 +/- 0.9 in group II, and 1.9 +/- 0.3 in group III (P=0.004 group I vs. group III). There were no ARs clinically diagnosed during this follow-up period in any of the three groups of patients, but there were significantly higher SCr increments among group III patients after the 1 year of follow-up. The detection of an active urine sediment by flow cytometry in "clinically stable" allograft recipients may indicate ongoing, subclinical acute rejection activity, which in this study was found to be associated with worse renal function at the end of the first posttransplant year as compared with patients with persistently negative UFCs. Increased immunosuppression may be indicated for these patients with persistently positive UFCs.  相似文献   
992.
993.
This study tests the hypothesis that glycolytic regulation of KATP channel activity is altered in myocardial hypertrophy. Left ventricular (LV) subendocardial myocytes were isolated from cats with normal or left ventricular hypertrophied hearts (LVH). Saponin-permeabilized open cell-attached patch configurations of normal and LVH cells were exposed to an exogenous ATP consuming system containing hexokinase and 2-deoxyglucose. Phosphoenol pyruvate (PEP, substrate for the last ATP producing step in glycolysis) was applied extracellularly; ADP was present. In both cell types, KATP channels were activated in the absence of PEP, inhibited when PEP was added and activated again when PEP was removed, indicating the cells retained metabolic integrity and generated ATP in the proximity of their KATP channels. Single channel conductance in the absence of PEP was similar (70 pS, normal; 66 pS, LVH). However, LVH KATP channels showed enhanced activity (P0=0.50+/-0.03); normal (0.41+/-0.03) in PEP absence (P<0. 05). PEP responsiveness was reduced in LVH, with IC50, PEP increased to 23 microM; (11 microM normal). Lactate failed to activate KATP channels in both cell types. The concentration-P0 response curves obtained during exposure of open cells to exogenous ATP also revealed reduced responsiveness to ATP of LVH KATP channels (IC50, ATP=283 microM LVH; 93 microM normal). Our data indicate myocardial hypertrophy increases the maximal activity of KATP channels in the absence of ATP and reduces their responsiveness to ATP, including locally generated glycolytic ATP. These alterations in metabolic regulation of myocardial electrophysiology may contribute to diversity of action potential shortening in hypertrophied hearts during acute ischemia.  相似文献   
994.
Techniques for the separation/concentration of micro-organisms from background food matrices can be applied to increase the speed of analysis and ease of isolation and detection of target micro-organisms. One recent example of such a technique is the immunomagnetic separation (IMS) procedure that has been used for the separation of specific micro-organisms from foods. This paper describes the use of a novel biosorbent consisting of a Salmonella-specific bacteriophage (phage) immobilized to a solid phase that was used for the separation and concentration of Salmonella from food materials. This work has shown that a Salmonella-specific phage-based biosorbent could remove Salmonella from culture fluid and separate Salmonella from suspensions of other Enterobacteriaceae. The ease of production of phage, high affinity of phage-cell interaction and the ability of phage to infect host cells in heterogeneous environments indicates the potential of such a biosorbent as the basis for a reliable separation system in food microbiological analysis.  相似文献   
995.
Germinomas arising within the sella turcica are extremely rare. The association of intrasellar and a pineal region tumours is even more unusual. We report a 30-year-old man with germinomas in the sellar and pineal region.  相似文献   
996.
Factors that, according to nurse participants, influenced the application of what was learned in a pain program were explored by means of qualitative interviews. Participants indicated that the correspondence between the program and their personal view on pain management, attitudes toward the program and innovations in general, self-efficacy perceptions, and (un)familiarity and taboos with respect to program items influenced what they put into practice. In addition, participants indicated that interactions with colleagues, nursing managers, patients, and physicians affected their application of the program. Furthermore, organizational factors, such as limited time and lack of formal program implementation, were mentioned as influential.  相似文献   
997.
BACKGROUND: Posttransplant lymphoproliferative disorder (PTLD) has been observed with increasing frequency consequent to the availability of more effective and potent immunosuppression. Prior work suggested that a peripheral blood monitoring strategy detecting peripheral B lymphoproliferation was effective in the early diagnosis of PTLD among 7 of 179 (3.9%) consecutive transplant recipients. Each of those seven patients received at least one course of antithymocyte globulin, Minnesota antilymphocyte globulin, or OKT3 before developing PTLD. METHODS: To determine whether antiviral prophylaxis might reduce the incidence of PTLD, a subsequent group of 198 consecutive recipients received either ganciclovir or acyclovir during antilymphocyte antibody administration. When the donor or recipient were cytomegalovirus-seropositive, ganciclovir was given; acyclovir was used when both were cytomegalovirus-seronegative. Baseline and protocol posttransplant cell surface profiles were obtained using immunofluorescence and flow cytometry to detect T cells, lymphocyte activation markers, and the CD19 B cell antigen. RESULTS: Demographic factors, including the incidence of recipients more than 50 years of age, non-Caucasians, previous transplantation, and diabetes mellitus, were similar in both groups. Additionally, the number of patients receiving antilymphocyte preparations was similar. However, only one patient (0.5%) from the latter group who received preemptive antiviral therapy developed PTLD. Although elevations in CD19+ B cells preceded clinical PTLD among each of the seven earlier patients, evidence of peripheral B cell proliferation was not demonstrated for the sole patient from the latter group, which suggests a possible effect of antiviral therapy. CONCLUSIONS: Prophylactic antiviral therapy may reduce the sensitivity of peripheral monitoring for B lymphoproliferation, but the dramatic reduction in PTLD incidence strongly supports its use among transplant recipients at risk.  相似文献   
998.
The purpose of this study was to evaluate the safety and feasibility of front-line high-dose sequential (HDS) chemotherapy with peripheral blood stem cell (PBSC) transplantation in patients with newly diagnosed high-risk non-Hodgkin's lymphoma (NHL). Thirty-two patients with high-risk NHL (defined by the age-adjusted international index) underwent HDS chemotherapy followed by PBSC transplantation and consolidative radiotherapy. Twenty-eight patients (88%) had intermediate/high grade NHL and four patients (12%) had small noncleaved or lymphoblastic lymphoma. Twenty-four patients were classified as high-intermediate-risk (two risk factors) and eight patients were classified as high-risk (three risk factors). The five phases of HDS (see Fig. 1) consisted of Phase I (adriamycin, vincristine, and prednisone); Phase II (cyclophosphamide, filgrastim [G-CSF], and PBSC harvest); Phase III (methotrexate, leucovorin, vincristine; Phase IV (etoposide, filgrastim [G-CSF]); and Phase V (mitoxantrone, melphalan, autologous peripheral blood stem cell infusion, and filgrastim [G-CSF]). Radiation therapy was given to sites of previous bulk disease, 2400 cGy, (D + 30-100)]. Toxicity, engraftment, hospital utilization, overall survival, and relapse-free survival were evaluated. The high-dose sequential chemotherapeutic regimen was well tolerated. Treatment-related mortality was 6.25% with two deaths occurring secondary to sepsis and one death was caused by progressive disease. The major toxicity in Phase I-IV was grade 3 nausea/vomiting. The major toxicity in Phase V was grade 3 or 4 nausea/vomiting and mucositis. The median follow-up is 18.8 months (range 4-44 months). The overall survival (OS) and relapse-free survival (RFS) at 18 months for all patients were 78% (95% CI 37-90%) and 67% (95% CI 46-88%), respectively. The OS at 18 months for all patients, excluding the four patients with either small noncleaved or lymphoblastic lymphoma, was 82% (95% CI 65-98%) vs. 30% (95% CI 0-86%) (p = 0.0059). One patient in this latter group remains alive at 6 months follow-up. The RFS for all patients, excluding the four patients with either small noncleaved or lymphoblastic lymphoma, was 78% (95% CI 58-97%) vs. 0% (95% CI 0-0%) (p = 0.0004). High-dose sequential chemotherapy with initial PBSC transplantation is well tolerated and appears effective in high-risk NHL. Superior results were noted in patients with intermediate grade versus those with small noncleaved or lymphoblastic NHL.  相似文献   
999.
We used the expression of the immediate-early gene c-fos, a marker of neuronal activation, to localize brainstem neuronal populations functionally related to fictive cough (FC). In decerebrate, paralyzed, and ventilated cats, the level of Fos-like immunoreactivity (FLI) was examined in five groups of animals: (1) controls, sham-operated unstimulated animals; (2) coughing cats, including both animals in which FC was elicited by unilateral electrical stimulation of the superior laryngeal nerve (SLN) and (3) those in which FC was elicited by bilateral SLN stimulation; (4) stimulated-treated cats, in which bilateral SLN stimulation was applied after selective blockade of FC by codeine; and (5) codeine controls, sham-operated unstimulated cats subjected to administration of codeine. Fifteen brainstem structures were compared for numbers of labeled cells. Because codeine selectively blocks FC, brainstem nuclei activated specifically during FC were identified as regions showing increased FLI after FC and significant reductions in FLI after FC suppression by codeine in stimulated-treated cats. In coughing animals, we observed a selective immunoreactivity in the interstitial and ventrolateral subdivisions of the nucleus of the tractus solitarius, the medial part of the lateral tegmental field, the internal division of the lateral reticular nucleus, the nucleus retroambiguus, the para-ambigual region, the retrofacial nucleus, and the medial parabrachial nucleus. FLI in all these nuclei was significantly reduced in stimulated-treated cats. Our results are consistent with the involvement of neurons overlapping the main brainstem respiratory-related regions as well as the lateral tegmental field and the lateral reticular nucleus in the neural processing of laryngeal-induced FC.  相似文献   
1000.
STUDY DESIGN: Frameless stereotaxy with doppler ultrasound and three dimensional computer model registration is assessed in vitro for pedicle screw placement. OBJECTIVE: To identify feasibility of pedicle screw navigation and placement using this technology. SUMMARY OF BACKGROUND DATA: Inaccurate pedicle screw placement can lead to neurovascular injury or suboptimal fixation. Present techniques in pedicle screw placement involve only confirmation of hole orientation. METHOD: Forty-four pedicle screws were placed in lumbosacral models and cadaver specimens. Accuracy was assessed with a computed tomography scan and vertebral cross sectioning. RESULTS: All screws were intrapedicular. Accuracy of anterior cortical fixation was 1.5 mm, with a range of 2.5 mm. CONCLUSION: In vitro frameless stereotaxy is accurate for pedicle screw placement. This technology adds a component of navigation to pedicle screw placement.  相似文献   
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