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991.
992.
Background: The first reported case of radiation (XRT) recall related to capecitabine described dermatitis in a previously radiated field in a breast cancer patient (Ortman; JCO). We previously reported the first case of recall syndrome manifesting as diffuse gastritis and duodenitis related to capecitabine with prior XRT with 5-FU in a pancreatic cancer patient (Saif; JARCET). We report here another pancreatic cancer patient with a radiation recall receiving capecitabine following capecitabine-XRT. Patients and methods: From April 2004 to June 2005, 20 patients with locally advanced pancreatic adenocarcinoma were treated with capecitabine 1,600 mg/m2 daily with concomitant radiation (5040cGy) Monday–Friday (weekends off) for a total of 6 weeks, followed by capecitabine 2,000 mg/m2 daily for 14 days every 3 weeks. One male patient with tumor in the neck and body of pancreas and not infiltrating the duodenum dropped hemoglobin to 7.3 g/dl at the end of the ninth week, and melena on rectal examination. Specimen of primary pancreatic ductal adenocarcinoma was obtained via EUS-guided biopsy before starting XRT on day 1 and utilized for RNA extraction. TP mRNA level was determined by real-time quantitative PCR (RT-Q-PCR). Results: Upper endoscopy revealed gastritis consistent with radiation toxicity. Colonoscopy was negative. Transfusion of three units of packed red blood cells (PRBCs) was given. The dose of capecitabine was reduced by 25%. His anemia continued to progress, a CT scan revealed 39% decrease in the tumor size (PR). Analysis of tumor specimen prior to the start of capecitabine-XRT showed TP expression of 183.16 (high). In addition to TP, DPD was 7.40, and TNF-alpha 4,114.56. Conclusion: We believe this case to be the second case of radiation recall presenting as diffuse gastritis in a patient receiving capecitabine after previous treatment with XRT. Further studies, including the role of TP are warranted into the pathogenesis of this unique phenomenon.  相似文献   
993.
This phase II trial investigated the safety and preliminary efficacy of a topotecan/thalidomide combination therapy in patients with myelodysplastic syndrome who had refractory anemia with excess blasts (RAEB), RAEB with transformation, or chronic myelomonocytic anemia. Patients received three 21-day cycles of topotecan 1.25 mg/m2 on days 1-5, which was repeated for two additional cycles in patients whose bone marrow blast percentages did not decrease. Oral thalidomide was then started at 100 mg/day (with the dose escalated up to 300 mg/day if well tolerated) for up to 1 year. Patients were monitored throughout the trial for hematologic and clinical adverse events, and efficacy was assessed using International Working Group (IWG) criteria. Forty-five patients, mostly elderly (median age 68 years; range 52-79 years), were enrolled. Therapy was generally well tolerated compared to high-dose chemotherapy. Three patients died from disease progression/infections during topotecan therapy, and four patients discontinued topotecan because of high-grade neutropenia (two patients), syncope (one patient), or hip surgery (one patient). Of 24 patients who received thalidomide, three discontinued because of treatment-related toxicity. Thirty-eight patients were evaluable for response: nine (24%) had hematologic improvement and 13 (34%) had stable disease. Responses occurred in patients with all disease subtypes. Six patients achieved transfusion independence, and one patient had a trilineage response. Approximately one-third of the patients had decreases in bone marrow blasts of ≥50%. Therefore, a topotecan and thalidomide combination therapy is promising, although further studies are needed to determine the optimum doses and schedule.  相似文献   
994.
Sarcococca saligna is a shrub that is traditionally used for its medicinal properties in Pakistan. In this study we report the cardio-suppressant, vasodilator and tracheal relaxant activities of the aqueous-methanolic extract (Ss.Cr) of the plant. Ss.Cr, that tested positive for the presence of saponins, flavonoids, tannins, phenols, and alkaloids, exhibited a dose-dependent (0.3-5 mg/mL) negative inotropic and chronotropic effect on the isolated guinea-pig atrium which was resistant to atropine (1 microM) and aminophylline (10 microM) pretreatment. In rabbit thoracic aorta, Ss.Cr dose-dependently (0.1-3 mg/mL) relaxed the high K+ (80 mM) and phenylephrine (PE, 1 microM)-induced contractions, indicating a possible Ca++ channel blocking (CCB) effect. When tested against PE (1 microM) control peaks in normal Ca++ and Ca++-free Kreb's solution, Ss.Cr exhibited dose-dependent (0.1-3 mg/mL) inhibition, being more potent in relaxing the PE responses in Ca++-free Kreb's solution, thus indicating specific blockade of Ca++ release from the intracellular stores. Ss.Cr also relaxed the agonist-induced contractions in: a) rat aorta irrespective of the presence of endothelium or nitric oxide synthase inhibitor L-NAME and b) rabbit and guinea-pig tracheal strips. The data shows that Ss.Cr possesses possible Ca++ channel blocking activity which might be responsible for its observed cardio-suppressant, vasodilator and tracheal relaxant effects though more tests are required to confirm this Ca++ channel blocking effect.  相似文献   
995.
A new flavanone Persinol (1) and the new flavanone glucosides persinosides A (2) and B (3), along with known flavonoids (4 and 5) have been isolated from the ethyl acetate soluble fraction of the whole plants of Aerva persica. Their structures were elucidated on the basis of extensive analysis of nuclear magnetic resonance (1D and 2D-NMR) spectral data. All of them showed profound antioxidative activities by DPPH and cytochrome-c-reduction assays using the HL-60 cell culture system.  相似文献   
996.
We present a case with dihydropyrimidine dehydrogenase (DPD) deficiency that manifested a variant of hand-foot syndrome (HFS). A 52-year-old man received capecitabine for adjuvant treatment of rectal cancer. On the ninth day of the first cycle, he presented to the clinic with a rash on the dorsum of both hands accompanied by symptoms of pain, erythema, swelling, and desquamation consistent with grade 3 HFS. The palms of his hands and soles of his feet were only tender with no apparent rash or discoloration. Dihydropyrimidine dehydrogenase activity was evaluated by radio assay using peripheral blood mononuclear cells. Dihydropyrimidine dehydrogenase activity was below normal: 0.12 nmol/minute/mg protein. Capecitabine was not resumed, and the rash resolved in 3 weeks with the use of pyridoxine and Udderly Smooth balm. Interestingly, HFS is rarely seen with 5-fluorouracil regimens containing selective DPD-inhibitors. This patient with DPD deficiency manifested a variant of HFS. The pharmacologic basis for the development of HFS in DPD-deficient patients warrants further investigation. Dihydropyrimidine dehydrogenase deficiency, if undiagnosed, can lead to death. In addition to severe to life-threatening toxicities akin to 5-fluorouracil, capecitabine can lead to unusual variants of common toxicities, including HFS, in DPD-deficient patients.  相似文献   
997.
OBJECTIVE: On the basis of a case study in Pakistan, the paper argues that good governance, characterized by transparency, accountability and meaningful community participation, plays a critical role in the sustainability of donor-funded health systems projects in the public health sector. METHODS: The Family Health Project (FHP) (1992-1999), funded by the World Bank, has been used as a case study. Critical analysis of secondary data mainly obtained from the Department of Health (DoH) in the province of Sindh in Pakistan is the major tool used for the study. Data from other sources including the World Bank have also been used. RESULTS: The analysis reveals that the existing health care system could not fully absorb and sustain major "sociopolitical" thrusts of the project, meaningful community participation and "democratic" decision-making processes being the most important ones. The hierarchical structure and management process made it difficult to produce a sense of ownership of the project among all managers and the rank and file staff. The Provincial Health Development Center (PHDC) and District Health Development Centers (DHDCs) established by the FHP did not receive adequate financial and political support from DoH and the Ministry of Health to have much control of the project at the local level. Consequently, these Centers largely failed to institutionalize a continuing training program for district level health officials/professionals. Due to lack of political support, the District Health Management Teams (DHMTs) could not be institutionalized. Community participation in the DHMTs was symbolic rather than forceful. Improved coordination among all stakeholders, more stable and competent leadership, more meaningful community participation, greater devolution of project management to the district level, and better management of resources would have resulted in more effective and efficient implementation of the project. Based on these findings, the paper introduces a Sustainable Management Approach (SMA) as a tool that can be used to ensure the sustainability of health systems projects, particularly those funded by international organizations in developing countries. CONCLUSIONS: Good governance and a conducive organizational culture are important prerequisites for incorporating any new project within an existing system. This includes prior consensus building among all stakeholders, a meaningful and inclusive participatory planning, implementation and evaluation process involving communities, political commitment, and the identification and use of appropriate leadership for project management.  相似文献   
998.
OBJECTIVES: To illustrate how multiple hypotheses testing can produce associations with no clinical plausibility. STUDY DESIGN AND SETTING: We conducted a study of all 10,674,945 residents of Ontario aged between 18 and 100 years in 2000. Residents were randomly assigned to equally sized derivation and validation cohorts and classified according to their astrological sign. Using the derivation cohort, we searched through 223 of the most common diagnoses for hospitalization until we identified two for which subjects born under one astrological sign had a significantly higher probability of hospitalization compared to subjects born under the remaining signs combined (P<0.05). RESULTS: We tested these 24 associations in the independent validation cohort. Residents born under Leo had a higher probability of gastrointestinal hemorrhage (P=0.0447), while Sagittarians had a higher probability of humerus fracture (P=0.0123) compared to all other signs combined. After adjusting the significance level to account for multiple comparisons, none of the identified associations remained significant in either the derivation or validation cohort. CONCLUSIONS: Our analyses illustrate how the testing of multiple, non-prespecified hypotheses increases the likelihood of detecting implausible associations. Our findings have important implications for the analysis and interpretation of clinical studies.  相似文献   
999.
A randomized single-dose crossover study was conducted in 24 healthy male volunteers to compare the bioavailability of two amoxicillin (CAS 26787-78-0) formulations, Glomox tablet (test) and a commercially available original preparation, amoxicillin capsule (reference). One thousand milligram of each formulation were administered after an overnight fast with a washout period of three days. Sixteen blood samples were collected over 10 h, amoxicillin concentrations in deproteinized serum were determined by a high performance liquid chromatographic (HPLC) assay, and pharmacokinetic parameters were analyzed by the standard non-compartmental method. Mean +/- SD maximum concentration (Cmax), time to reach maximum concentration (Tmax), area under the curve (AUC0-->t and AUC0-->infinity), and elimination half-life (t1/2) were 13.30 +/- 4.52 and 12.99 +/- 3.56 microg/ml, 1.92 +/- 0.76 and 2.02 +/- 0.62 h, 42.50 +/- 13.62 and 42.24 +/- 12.35 microg x h/ml, 46.31 +/- 13.23 and 46.08 +/- 12.14 microg x h/ml, and 1.54 +/- 0.39 and 1.48 +/- 0.48 h for the test and reference formulation, respectively. The parametric 90 % confidence intervals of the mean of the difference (test-reference) between log-transformed values of the two formulations were 92.61% to 109.50%, 92.83% to 109.12%, and 93.11% to 109.41% for AUC0-->t, AUC0-->infinity, and Cmax, respectively. The results indicate that the two formulations can be considered equivalent with regard to the rate and extent of absorption under fasting conditions.  相似文献   
1000.
An expedient high-performance liquid chromatography (HPLC) assay for nizatidine measurement in human plasma was developed and validated. After deproteinization of 200 microL of plasma by filtration, nizatidine and 4-amino-antipyrine (internal standard) were separated (capacity ratio 3.0 and 6.63, respectively) on Nova-Pak C18 cartridge at room temperature (RT), and detected spectrophotometrically at 320 nm. The mobile phase, 0.02 mol/L disodium hydrogen phosphate, acetonitrile, methanol, and triethylamine (80:10:10:0.05 vol/vol), was delivered at 1.5 mL/min. Calibration curves were linear (r2 > or = 0.999) in the range 0.02 to 5 microg/mL, detection and quantification limits were 0.01 and 0.02 microg/mL, respectively, intra-run and inter-run coefficients of variation were < or = 3.5% and < or = 4.2%, respectively, and recovery was >90%. Nizatidine was stable for at least 4 hours at RT, 12 weeks at -20 degrees C, and 3 freeze-thaw cycles in plasma; 16 hours at RT and 48 hours at -20 degrees C in deproteinized plasma; and 6 hours at RT and 3 weeks at -20 degrees C in water.  相似文献   
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