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91.
Questionnaires were distributed among 200 medical students regarding safety precautions observed while perfonning various invasive procedures during their clinical posting. Only 106 students responded with the completed questionnaire. The most common procedure performed by the students was drawing of blood, with an average frequency of 60.8 per month. Sixty-one per cent of the students reported being injured during the various procedures and only 3 5.5% of them used gloves. Resheathing the needle was responsible for causing injury to 69% of the students, which was significantly higher than injuries occurring while entry into the vein or withdrawing the needle (p<0.05). 相似文献
92.
R. R. Mehta J. M. Graves A. Shilkaitis T. K. Das Gupta 《British journal of cancer》1998,77(4):595-604
Xenografts originated from human tumours offer the most appropriate research material for in vivo experimental research. However, primary human breast carcinomas are difficult to grow when transplanted in athymic mice: tumour take is less than 15%. Recently, we have achieved 60% tumour take by injecting tumour cell suspensions mixed with Matrigel. Human breast xenografts originated from primary breast carcinoma also frequently show the potential to metastasize spontaneously. In the present study, we generated a human breast carcinoma xenograft line (UISO-BCA-NMT-18) that shows 100% tumorigenicity and 80-100% lung metastasis when transplanted s.c. in athymic mice. We have studied in detail the characteristics of the xenograft and the patient''s tumour from which the xenograft line originated. Both the xenograft and the patient''s tumour showed intense staining for mutant p53 nuclear protein, and high expression of U-PA, PAI and u-PAR. In vivo growth of the xenograft is stimulated by exogenous supplementation of oestrogen. This xenograft is continuously growing in mice and has shown 80-100% metastasis for the last three successive in vivo passages. This well-characterized, oestrogen-responsive, metastatic breast carcinoma xenograft line will provide excellent research material for metastasis-related research. 相似文献
93.
This study analysed a sample of food advertisements shown during 63 hours of children's programming to investigate compliance and non‐compliance with one of the Australian Children's Television Standards (CTS): CTS 20.2a. This standard regulates the way premium offers may, and may not, be used to sell products to children. Of the 1721 advertisements contained in the sample, 544 (32%) were for food. A significantly higher number of food advertisements (41%) were shown during ‘C’ programs (which are specifically regulated and produced for children six to 13 years of age and suitable for viewing without adult supervision), compared with 30% during the less regulated ‘G’ programs (P= < 0.001) (suitable for children to view without adult supervision but not produced specifically for a child audience). Over one‐third of food advertisements (36%) in ‘C’ time contained a premium offer compared with 17% in ‘G’ time (P= < 0.0001). Using a precisely defined interpretation of CTS 20.2a, this study found 30 (31%) of food advertisements breached the standard during ‘C’ programs. This was a significantly higher proportion than the 54 (12%) of breaches in ‘G’ time (P= < 0.0001). From this study, the current regulatory system has not resulted in more responsible food advertising during ‘C’ programs, and the widespread breaches of CTS 20.2a indicate this standard is ineffective as a means of regulating food advertising. The Australian Broadcasting Authority has recognised that children need protection from unfair marketing practices and the improper use of premium offers to promote a food product, therefore CTS 20.2a needs urgent review to make it more effective. 相似文献
94.
OBJECTIVES: To determine whether pulse oximetry-detected episodes of desaturation are associated with impairment of cerebral and somatic (renal) tissue oxygenation in mechanically ventilated preterm neonates. DESIGN: Observational cross-sectional study. SETTING: Neonatal intensive care unit of a university-affiliated children's hospital. PATIENTS: Ten mechanically ventilated preterm (gestational age 24-32 wks) infants. INTERVENTIONS: In addition to the traditional monitoring of hemodynamic variables that included pulse oximetry (Sao2), near-infrared spectroscopy (NIRS) was used to evaluate the cerebral and somatic (renal) tissue oxygen saturation (rSO2C and rSO2R, respectively). MEASUREMENTS AND MAIN RESULTS: A total of 40 rSO2C and rSO2R measurements were simultaneously recorded: 20 during hypoxic events when the Sao2 was =80% for >/=4 secs (cases) and generally ranged between 70% and 80%, and 20 measurements when the Sao2 was >/=85% (paired controls). Additionally, the fractional oxygen extraction (FOE) from the cerebral (FOEC) and renal (FOER) tissue was calculated. All the measurements were made under steady conditions during a 2-hr period. The rSO2C, rSO2R, FOEC, and FOER among the cases (Sao2 = 80%) and controls (Sao2 >/= 85%) were compared using the paired Student's t-test. Both rSO2C and rSO2R during the desaturation episodes were lower than in the controls (51.6 +/- 6.3% vs. 66.2 +/- 10.2%, p < .0001 and 61.1 +/- 6.8% vs. 80.1 +/- 10.0%, p < .0001, respectively). The FOEC during the hypoxic episodes was comparable with control levels but increased in renal tissue. However, during two of the desaturation episodes (10%), the rSO2C and FOEC levels (which were <44% and >0.47, respectively) may reflect compromised tissue oxygen supply. CONCLUSIONS: In the majority of mechanically ventilated preterm neonates, the reduction in cerebral and renal tissue oxygenation associated with short periods of decreased arterial saturation to 70-80% does not significantly compromise oxygen utilization in the cerebral tissue but increases oxygen extraction in the renal tissue, which might cause ischemic tissue injury following a further reduction in oxygen delivery. 相似文献
95.
Resveratrol inhibits rhabdomyosarcoma cell proliferation. 总被引:2,自引:0,他引:2
A W Chow G Murillo C Yu R B van Breemen A W Boddie J M Pezzuto T K Das Gupta R G Mehta 《European journal of cancer prevention》2005,14(4):351-356
Rhabdomysarcoma is the most common soft tissue tumour in children under the age of 15. Although the introduction of multimodal treatment programmes, including chemotherapy, radiation therapy and excision have increased the overall survival, the chemotherapeutic agents currently used for the treatment of rhabdomyosarcoma exhibit considerable toxicity. The aim of this study was to investigate the effects and possible mechanism(s) of action of resveratrol on human embryonal rhabdomyosarcoma (RD) cells. Resveratrol is a natural polyphenolic compound produced in a number of edible plants and has received considerable attention as a potential chemopreventive and/or chemotherapeutic agent against various types of cancers. In the present study, resveratrol was shown to inhibit cell proliferation of RD cells in a dose-dependent manner with an IC50 of 48.1 micromol/l and induce an arrest in the S/G2 phase of the cell cycle. As evident from immunocytochemical data, resveratrol treatment increased the size of the RD cells. Furthermore, resveratrol treatment resulted in a significant downregulation of cyclin B expression as demonstrated by western blot analyses. In conclusion, the present study shows that resveratrol exerts a strong inhibition of rhabdomyosarcoma cell proliferation in part by arresting cells in S/G2 phase of the cell cycle. These findings warrant further investigation to establish potential use of resveratrol as a relatively non-toxic chemotherapeutic agent for the treatment of rhabdomyosarcoma. 相似文献
96.
Timothy F Cloughesy John Kuhn H Ian Robins Lauren Abrey Patrick Wen Karen Fink Frank S Lieberman Minesh Mehta Susan Chang Alfred Yung Lisa DeAngelis David Schiff Larry Junck Morris Groves Steve Paquette John Wright Kathleen Lamborn Said M Sebti Michael Prados 《Journal of clinical oncology》2005,23(27):6647-6656
PURPOSE: To determine the maximum-tolerated dose (MTD), toxicities, and clinical effect of tipifarnib, a farnesyltransferase (FTase) inhibitor, in patients with recurrent malignant glioma taking enzyme-inducing antiepileptic drugs (EIAEDs). This study compares the pharmacokinetics and pharmacodynamics of tipifarnib at MTD in patients on and off EIAEDs. PATIENTS AND METHODS: Recurrent malignant glioma patients were treated with tipifarnib using an interpatient dose-escalation scheme. Pharmacokinetics and pharmacodynamics were assessed. RESULTS: Twenty-three assessable patients taking EIAEDs received tipifarnib in escalating doses from 300 to 700 mg bid for 21 of 28 days. The dose-limiting toxicity was rash, and the MTD was 600 mg bid. There were significant differences in pharmacokinetic parameters at 300 mg bid between patients on and not on EIAEDs. When patients on EIAEDs and not on EIAEDs were treated at MTD (600 and 300 mg bid, respectively), the area under the plasma concentration-time curve (AUC)(0-12 hours) was approximately two-fold lower in patients on EIAEDs. Farnesyltransferase inhibition was noted at all tipifarnib dose levels, as measured in peripheral-blood mononuclear cells (PBMC). CONCLUSION: Toxicities and pharmacokinetics differ significantly when comparing patients on or off EIAEDs. EIAEDs significantly decreased the maximum concentration, AUC(0-12 hours), and predose trough concentrations of tipifarnib. Even in the presence of EIAEDs, the levels of tipifarnib were still sufficient to potently inhibit FTase activity in patient PBMCs. The relevance of these important findings to clinical activity will be determined in ongoing studies with larger numbers of patients. 相似文献
97.
Rafael Manon Anne O'Neill Jonathan Knisely Maria Werner-Wasik Hillard M Lazarus Henry Wagner Mark Gilbert Minesh Mehta 《Journal of clinical oncology》2005,23(34):8870-8876
PURPOSE: Long-term brain metastases survivors are at risk for neurologic morbidity after whole-brain radiotherapy (WBRT). Retrospective radiosurgery (RS) reports found no survival difference when compared with WBRT. Before RS alone was evaluated with delayed WBRT in a phase III trial, the feasibility of RS alone was tested prospectively. PATIENTS AND METHODS: Patients with renal cell carcinoma, melanoma, or sarcoma; one to three brain metastases; and performance status of 0 to 2 were enrolled. Exclusion criteria were leptomeningeal disease; metastases in medulla, pons, or midbrain; or liver metastases. On the basis of tumor size, patients received 24, 18, or 15 Gy RS. At recurrence, management was discretionary. The primary end point was 3- and 6-month intracranial progression. RESULTS: Between July 1998 and August 2003, 36 patients were accrued; 31 were eligible. Median follow-up was 32.7 months and the median survival was 8.3 months (95% CI, 7.4 to 12.2). Three- and 6-month intracranial failure with RS alone was 25.8% and 48.3%. Failure within and outside the RS volume, when in-field and distant intracranial failures were scored independently, was 19.3% and 16.2% (3 months) and 32.2% and 32.2% (6 months), respectively. Approximately 38% of patients experienced death attributable to neurologic cause. There were three grade 3 toxicities related to RS. CONCLUSION: Intracranial failure rates without WBRT were 25.8% and 48.3% at 3 and 6 months, respectively. Delaying WBRT may be appropriate for some subgroups of patients with radioresistant tumors, but routine avoidance of WBRT should be approached judiciously. 相似文献
98.
Gupta Sumita Mukherjee Aparna Lodha Rakesh Kabra Madhulika Deepak Kishore K. Khadgawat Rajesh Talwar Anjana Kabra Sushil Kumar 《Indian journal of pediatrics》2019,86(11):987-994
Indian Journal of Pediatrics - To evaluate effect of one year exercise intervention program on bone mineral accrual in children and adolescent with cystic fibrosis (CF). Fifty-two CF children (mean... 相似文献
99.
Anood Alassaf Khaled Ellithy Tejas Mehta Walid Aljbawi Hossamaldein Ali Ashraf Soliman Mohammed Al Amri Abdulqadir J. Nashwan 《Clinical Case Reports》2022,10(8)
Our patient is a 3‐week‐old female neonate, presented with complaints of low‐grade fever and a congested nose for one day. Eventually, she developed progressive desaturation, hypotension, and poor perfusion due to severe pulmonary hemorrhage. Then, she developed cardiac arrest and was declared dead. 相似文献
100.
Pooja Khandelwal Julia Lawrence Alexandra H. Filipovich Stella M. Davies Jacob J. Bleesing Michael B. Jordan Parinda Mehta Sonata Jodele Michael S. Grimley Ashish Kumar Kasiani Myers Rebecca A. Marsh 《Pediatric transplantation》2014,18(1):94-102
SR‐aGVHD remains a significant cause of morbidity and mortality in allogeneic HCT recipients. Alemtuzumab has been used with success in adult patients but has not been studied in the pediatric setting. To estimate the effectiveness of alemtuzumab for the treatment of SR‐aGVHD in pediatric patients, we retrospectively reviewed the charts of 19 patients (median age 4 yr, range 0.5–28 years) with grades II (n = 3), III (n = 10), or IV (n = 6) SR‐aGVHD who received alemtuzumab treatment. Patients received a median dose of 0.9 mg/kg alemtuzumab (range 0.3–2 mg/kg) divided over 2–6 days. Eighty‐nine percent of patients received additional courses. A complete response, defined as GVHD of grade 0 at four wk following the first alemtuzumab course, was observed in nine patients (47%). A partial response, defined as an improvement in grade after four wk, was observed in five patients (26%). There was no response in five patients (26%). The overall response rate at four wk was 73%. Infectious complications included bacteremia (47%), presumed or documented fungal infections (21%), adenovirus viremia (52%), EBV viremia (36%), and CMV viremia (36%). We conclude that alemtuzumab is effective for SR‐aGVHD in pediatric patients with a tolerable spectrum of complications. 相似文献