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排序方式: 共有847条查询结果,搜索用时 31 毫秒
1.
Irene T Lynch Joseph A Eustace Willliam D Plant Kevin D Cashman Majella O'Keefe Sinead Lordan Rachel Moloney 《Journal of renal nutrition》2007,17(6):408-415
OBJECTIVE: To quantify the dietary calcium and vitamin D intake in adult renal-transplant recipients attending at a large teaching hospital in Ireland for follow-up. SETTING: Outpatient renal-transplant follow-up clinic. SUBJECTS: Fifty-nine adult renal transplant recipients (58% male) with a mean age of 46 years, a median transplant duration of 6 years, and a mean estimated glomerular filtration rate (eGFR) of 50 mL/min per 1.73 m2. Fifty-three percent were at National Kidney Foundation stage 3 chronic kidney disease, and 14% had stage 4 chronic kidney disease. INTERVENTION: This cross-sectional, observational study used a tailored food frequency questionnaire specific for calcium and vitamin D intake in Irish adults, which was completed during a face-to-face interview with each subject. MAIN OUTCOME MEASURE: The main outcome measure was the average daily dietary and supplemented calcium and vitamin D intake. RESULTS: The median interquartile range (IQR) dietary calcium intake was 820 mg/day (range, 576-1,177 mg/day), and was similar in men and women (recommended intake > or = 1,000 mg/day in adult men and nonmenopausal adult women, > or = 1,500 mg/day in menopausal women). Five participants received calcium supplementation. Overall, 59% of men and 64% of women had total calcium intakes below the recommended amounts. The median IQR estimated dietary vitamin D intake was 5.2 microg/day (range, 2.4-6.4 microg/day) in women, and 4.6 microg/day (range, 2.2-6.6 microg/day) in men (recommended intake, > or = 10 microg/day). Six subjects received vitamin D supplementation. Total vitamin D intakes were suboptimal in 91% of men and 87% of women. Dietary calcium and vitamin D intakes significantly correlated with each other, but neither was significantly related to eGFR category, and was similarly low in both presumed menopausal women and in the initial year posttransplantation. CONCLUSION: These findings suggest that dietary and total calcium and vitamin D intakes in adult renal-transplant patients are in many cases inadequate. 相似文献
2.
Fernando Cendes Frederick Andermann Stirling Carpenter Robert J. Zatorre Neil R. Cashman 《Annals of neurology》1995,37(1):123-126
We describe the development of temporal lobe epilepsy in an 84-year-old man who had suffered domoic acid intoxication. Following intoxication he had nausea, vomiting, confusion, and coma. Generalized convulsions and complex partial status epilepticus progressively developed. After 3 weeks he improved and was seizure free with severe residual memory deficit. Electroencephalograms initially showed periodic epileptiform discharges, later evolving to epileptic abnormalities over frontotemporal regions with diffuse slow waves. Eight months after the intoxication the electroencephalogram was normal. One year after the acute episode, complex partial seizures developed. Electroencephalograms showed epileptic discharges independently over both temporal lobes, with left-sided predominance. Magnetic resonance imaging revealed a hyperintense T2-weighted signal and atrophy of both hippocampi; a positron emission tomographic scan showed bitemporal decreased glucose metabolism. Pneumonia developed and the patient died 31/4 years after the intoxication. Autopsy disclosed severe bilateral hippocampal sclerosis. The seizures following acute domoic acid intoxication, the postmortem pathology, and the fact that temprol lobe epilepsy developed 1 year after intoxication indicate that the human hippcampus is also vulnerable to kainate receptor excitotoxicity, and provide strong evidence supporting the role of excitotoxic injury in epileptogenesis. This report provides a unique human parallel to, and validates the animal model of, Kainate-induced epilepsy as an important tool for studying temporal lobe epilepsy. 相似文献
3.
The reaction of NalO4, highly purified flavin-containing monooxygenase (EC 1.14.13.8), and microsomes from hog liver with 2-aryl-1,3-dithiolanes and 2-aryl-1,3-dithiolane S-oxides was investigated. The initial rates determined for the microsome- and purified flavin-containing monooxygenase-catalyzed rate of S-oxidation of para-substituted 2-aryl-1,3-dithiolanes were similar, demonstrating that S-oxidation of these substrates occurred with similar velocities at saturating concentrations of substrate and, at least for the first S-oxidation, the reaction was insensitive to the nature of the para-substituent. The diastereoselectivity of S-oxygenation of 2-aryl-1,3-dithiolanes was determined and, in general, a marked preference for addition of oxygen to the sulfide sulfur atom was observed to occur trans to the aryl groups. In all cases examined, enantioselective enzymatic S-oxidation was observed. For S-oxide formation in microsomes, the data provided evidence for a minor role of cytochrome P-450 in S-oxide formation, but the flavin-containing monooxygenase was mainly responsible for production of S-oxide. In contrast to previous reports, the enantioselectivity of S-oxidation catalyzed by highly purified cytochrome P-450IIB-1 and cytochrome P-450IIB-10 was not always opposite to that catalyzed by hog liver flavin-containing monooxygenase activity. 2-Aryl-1,3-dithiolane S-oxides were also oxidized a second time by NalO4, microsomes, or highly purified flavin-containing monooxygenase from hog liver but not cytochrome P-450IIB-1 or P-450IIB-10. The rate of the second oxidation was 10-15-fold slower than the corresponding first S-oxidation and S,S'-dioxide formation was markedly dependent on the electronic nature of the para-substituent (Hammett correlation rho value of -1.3 and -1.1 for microsomes and highly purified flavin-containing monooxygenase from hog liver, respectively). The large dependence of the rate of S,S'-dioxide formation on the nature of the para-substituent demonstrates that velocity values at saturating concentrations of S-oxide were not the same for all 2-aryl-1,3-dithiolane S-oxides and suggests that the chemical nature of the 2-aryl-1,3-dithiolane S-oxide contributes to the rate-determining step of this enzymatic reaction. 相似文献
4.
Cardiopulmonary Resuscitation is the 28th title in the ContemporaryCardiology series, by Humana Press. The editors state that thebook is intended to provide the latest information onthe science and practice of CPR by exploring thephysiology behind current state-of-the-art clinical resuscitationin depth. The book provides an extremely comprehensivereview of all aspects of resuscitation. However, with the vastmajority of 相似文献
5.
Suresh Kumar Masilamani Annamalai Rachel Buckingham John Cashman 《Journal of children's orthopaedics》2007,1(2):107-113
The treatment of Legg-Calvé-Perthes disease remains controversial. The aim of this survey was to ascertain the current management
strategies of this condition amongst UK paediatric orthopaedic surgeons, with particular regard to containment procedures
in the fragmentation phase. Questionnaires were distributed at the January 2006 meeting of the British Society for Children’s
Orthopaedic Surgery (BSCOS) and was posted to all absent members. The results showed a great deal of variability not only
in the treatment of Perthes disease, but also in the decision-making processes. Consideration must now be given to a carefully
constructed national multi-centre prospective randomised controlled study into the optimum management of this disease 相似文献
6.
Celeste A. Lemay Suzanne B. Cashman Judith A. Savageau Patricia A. Reidy 《Journal of nursing scholarship》2004,36(4):312-315
PURPOSE: Evaluate the effectiveness of body mass index (BMI) tables placed in exam rooms as an intervention to encourage providers to calculate and record BMI scores in patients' medical records. DESIGN: In a prospective cohort design, medical record data for 276 adult patients at a federally funded community health center in New England were examined from August 2000 to August 2002 following the intervention. METHODS: Prominent, multicolored, laminated BMI tables were posted in the exam rooms of one of the study site's three primary health care teams. Medical record data collected included documentation of BMI calculation in medical records, documentation of an obesity diagnosis, and inclusion of heights and current weights. Frequency distributions were calculated; chi-square tests were used to identify associations. FINDINGS: In contrast to the comparison teams, patients on the intervention team were more likely to have BMI recorded in the medical record. A statistically significant increase in the diagnosis of obesity was observed throughout the health center after the intervention. CONCLUSIONS: Posting BMI tables in exam rooms contributed to increased BMI documentation in patients' medical records. 相似文献
7.
Neuromuscular transmission as a function of motor unit size in patients with prior poliomyelitis. 总被引:2,自引:0,他引:2
We studied neuromuscular transmission in 16 patients with prior poliomyelitis by measuring single fiber electromyographic (SFEMG) jitter. This was compared with 3 indirect methods of assessing reinnervation: SFEMG fiber density, macro EMG, and the presence of fiber type grouping on muscle biopsy. In patients with acute poliomyelitis before the age of 10, there was a positive correlation between the extent of neuromuscular transmission impairment, demonstrated by increased SFEMG jitter, and the enlargement of the motor unit, as indicated by increased fiber density, increased macro EMG signals, and fiber type grouping on muscle biopsy. However, there was no correlation between any of these parameters and the presence or absence of new symptoms of weakness. These findings suggest that impaired neuromuscular transmission is most common in patients with prior poliomyelitis whose motor units have been maximally enlarged by axonal sprouting, but is independent of the presence or absence of new symptoms of weakness. 相似文献
8.
Testosterone (T) 6 beta-hydroxylase (6 beta-OHase) is a well-recognized functional marker of rat liver cytochrome P450 3A (P450 3A) isozymes. Pretreatment of rats with inducers or specific or nonspecific inhibitors of P450 3A isozymes is associated not only with stimulation or inhibition of hepatic microsomal T 6 beta-OHase activity but also with parallel changes in the corresponding T 2 beta-, 15 beta-, and 18-OHase activities and T 4,6-diene formation. At the time these studies were conducted, no fully functionally active rat hepatic P450 3A isozymes had been isolated. To determine whether each of these activities was due to a single P450 3A isozyme, or whether multiple isozymes contributed to these activities, we specifically synthesized two thiotestosterone (6 beta- and 2 beta-SHT) analogues as potential mechanism-based inactivators of rat liver T 6 beta- and 2 beta-OHases. In addition, to assess their relative stereoselectivity, 2 alpha-SHT was also included as a control. Our studies revealed that although all three thiosteroids were excellent suicide substrates of P450 3A isozymes, they inactivated these T OHases differentially. Such differential inactivation and determination of the kinetic parameters of inactivation allowed the functional classification of rat hepatic P450 3A isozymes into at least two and possibly three categories: (i) forms (catalyzing 4,6-diene and 6 beta-OHT formation but with characteristically low 6 beta/2 beta-OHase ratios) highly susceptible to inactivation by SHTs; (ii) forms (catalyzing T 6 beta-, 2 beta-, 15 beta-, and 18-hydroxylations with high 6 beta-/2 beta-OHase ratios) moderately susceptible to the SHTs; and (iii) forms somewhat resistant to inactivation, at least at the SHT concentrations tested. Although no specific T OHase could be ascribed to a single P450 3A isozyme, it appears that each of these P450s catalyzed such T regiohydroxylations, albeit at considerably different extents. Furthermore, our studies also revealed that 2 alpha-SHT preferentially inactivated P450 3A forms but surprisingly failed to inactivate rat hepatic P450 2C11, thereby confirming the rather high substrate promiscuity of the P450 3A family of isozymes. 相似文献
9.
Unregulated proliferation of primitive neoplastic progenitor cells in long-term polycythemia vera marrow cultures 总被引:2,自引:2,他引:0 下载免费PDF全文
Marrow cells from seven untreated patients with polycythemia vera (PV) were used to initiate standard single inoculum long-term marrow cultures. The numbers, erythropoietin independence, and cycling behavior of all detectable classes of erythroid, granulopoietic, and multilineage progenitors were then evaluated and the results obtained compared with preculture values. Time course studies showed that the long-term marrow culture system supports the continuous proliferation of primitive neoplastic progenitor cells from PV patients for many weeks. However, these progenitors fail to respond to signals from the adherent layer that return their counterparts in normal long-term marrow cultures to a quiescent state 5-7 d after each medium change. This abnormal cycling behavior of PV cells in the long-term culture system appears to mimic that operative in vivo, where primitive hemopoietic progenitors are also in a continuous state of turnover, in contrast to similar primitive progenitor compartments in normal individuals, which are quiescent. The long-term marrow culture system thus offers new possibilities for the further analysis of abnormal cellular and molecular mechanisms underlying clonal expansion at the stem cell level in PV. 相似文献
10.
A Fukui EI Ntrivalas A Gilman-Sachs J Kwak-Kim KD Beaman 《American journal of reproductive immunology (New York, N.Y. : 1989)》2006,55(6):395-395
Aim: To determine if IgA is required for protection against Chlamydia infection in the male reproductive tract (MRT).
Materials and Methods: Male polyimmunoglobulin receptor knockout mice (PIgR-/- ) and wild-type C57BL/6 (WT) mice were immunised intranasally with chlamydial major outer membrane protein (MOMP) and cholera toxin (CT). MOMP-specific IgG and IgA in serum and prostatic fluids were measured by ELISA. Serum and PF were also assayed for inhibition of in vitro chlamydial infection. Immunized WT and PIgR-/- mice were challenged by direct inoculation of C. muridarum into the meatus urethra. Four weeks post challenge Chlamydia levels in the penile urethra, epididymis and testis were determined by PCR.
Results: Equivalent levels of IgG were found in the serum of both WT and PIgR-/- mice however IgA in serum of PIgR-/- mice was 19- to 20-fold higher than in WT animals consistent with the lack of the PIgR IgA transport molecule. IgA levels were significantly lower in PIgR-/- PF compared to WT PF after both immunization and infection. Only PF from WT but not PIgR-/- animals was able to inhibit in vitro chlamydial infection. Following challenge significantly higher levels of Chlamydia were recovered from the MRT of PIgR-/- mice compared to WT animals.
Conclusions: Male mice lacking a functional PIgR were unable to clear a genital tract Chlamydia infection despite high levels of serum IgA. These data show that mucosal IgA plays a major role in preventing chlamydial infection of the male genital tract and suggest that immunization strategies to protect males should target a strong mucosal IgA response. 相似文献
Materials and Methods: Male polyimmunoglobulin receptor knockout mice (PIgR
Results: Equivalent levels of IgG were found in the serum of both WT and PIgR
Conclusions: Male mice lacking a functional PIgR were unable to clear a genital tract Chlamydia infection despite high levels of serum IgA. These data show that mucosal IgA plays a major role in preventing chlamydial infection of the male genital tract and suggest that immunization strategies to protect males should target a strong mucosal IgA response. 相似文献