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81.
Kelli J Kochan David A Wright Lisa J Schroeder Jianjun Shen Donald C Morizot 《Developmental dynamics》2003,226(1):99-102
Amphibians, and particularly the African clawed frog Xenopus laevis, have been used for more than a century as models of vertebrate embryonic development. However, in many cases, elucidation of developmental functions of specific gene sequences could be severely impeded, because X. laevis is a tetraploid species, with multiple functional copies of many genes of interest. Recent studies have shifted focus to the West African or tropical clawed frog, X. tropicalis, the only known diploid species of the genus Xenopus. Here, we present two preliminary linkage maps, constructed by analysis of joint segregation of amplified fragment length polymorphism (AFLP) markers in a X. tropicalis interstrain hybrid. A total of 53 markers, including 51 AFLP markers and 2 isozyme markers, are presently assigned to 13 multipoint linkage groups on a map of the maternal strain, whereas 9 AFLP markers from the paternal strain are assigned to 3 linkage groups on a separate map. A dense genetic linkage map is essential in mapping new developmental mutants and determining their sequences by positional cloning. 相似文献
82.
For patients with coronary artery disease and left ventricular dysfunction who undergo revascularization, it is important to estimate the left ventricular ejection fraction (LVEF) improvement after revascularization, as this is a strong indicator of the long-term outcome. Identification of viable segments from echocardiography has been considered a predictive sign of LVEF improvement. However, a quantitative relation between segmental function recovery and global ejection fraction improvement has not been established. There is a clinical need to determine parameters that are predictive to LVEF improvement. A cylindrical left ventricular model is proposed to establish the relation between segmental myocardial function and LVEF based on a 12-segment echocardiograph model. Model results show that LVEF improvement is directly related to the contraction ratio in normal segments and a weighted sum of the number of viable segments that recover to normal or hypokinetic, which is equal to a weighted sum of the change in wall motion scores. This new combined parameter is a better predictor of the amount of LVEF improvement than the total number of viable segments or preoperative ejection fraction. The predictive value of the model was illustrated in a group of four patients with coronary artery disease who underwent revascularization. 相似文献
83.
STUDY OBJECTIVES: Very few studies have evaluated narcolepsy in Asian countries, outside of Japan. Our goal was to study narcolepsy at the genetic, clinical and pathophysiological level in Korea. DESIGN: Prospective study of consecutive patients and age matched controls. Clinical data ascertained from the Stanford Sleep Inventory, Polysomnography and MSLT data, as well as clinical notes. High resolution DRB1 and DQB1 typing in all subjects and studies of CSF hypocretin-1 was also evaluated in a subset of patients. PARTICIPANTS AND SETTING: 20 patients diagnosed at St. Vincent and Korea University Hospitals (Seoul, Korea). 21 Korean control subjects. INTERVENTIONS: N/A. MEASUREMENTS AND RESULTS: For narcoleptic subjects, mean age was 28.2 years old and 45% were female. Mean BMI was 23.9+/-3.4 kg/m2, a significantly higher value than that expected in an age- and sex-matched sample (p<0.01). All patients had sleepiness and cataplexy while the prevalence of other symptoms ranged from 60-75%. All but 2 subjects were HLA-DR15 (DR2), DQB1*0602 positive (90%). This high DQB1*0602 percentage compared with 24% DQB1*0602 positivity in 21 control Koreans. Protective effects were observed for the DQB1*0601 and DRB1*0406 alleles, Hypocretin (orexin) CSF studies were also performed in 6 cataplectic subjects, all of which had undetectable CSF hypocretin levels. Two of these subjects had started narcolepsy less than 1 year before analysis yet had undetectable hypocretin levels. CONCLUSION: These results illustrate the similarity of narcolepsy-cataplexy in Korea in comparisons with other more studied populations. We also identified a new potential HLA protective subtype, HLA-DRB1*0406. 相似文献
84.
T H Lim J S Lee B I Choi I O Kim C H Suh M C Han C W Kim 《Journal of computer assisted tomography》1987,11(3):474-479
The pattern of renal enhancement and washout of contrast medium was observed on sequential follow-up CT in 12 patients with Korean hemorrhagic fever, in which acute renal failure is one of the most important clinical features. Renal contrast enhancement and contrast medium washout were delayed longer in patients with severe oliguric renal failure. The delayed washout peaked at 4-5 days and did not return to normal until 8-9 days in the patients with severe oliguria; in the patients without severe oliguria the times were 1-2 days and 3-4 days, respectively. A characteristic "cart-wheel" pattern was observed during the washout stage in patients without severe oliguria. This "cart-wheel" pattern of washout is thought to result from relief of vasoconstriction and repair of tubular function. Multifocal "wedge-shaped" nonenhanced areas of the kidney, seen on the 2 week follow-up postcontrast CT, are thought to be ischemic zones due to persistent vasoconstriction. On the 6 week follow-up postcontrast CT in one patient, scarring of the kidney was detected in the same area that did not enhance on the 2 week CT. This scarring is thought to be a result of permanent vasoconstriction. 相似文献
85.
Han Ji-sheng韩济生Department of Physiology Beijing Medical University Beijing 《中华医学杂志(英文版)》1987,100(6):459-464
roiiowing the rapid progress iri molecular bio
logy, we are moving from the period of "one peptide
a year" to a period of "one peptide a day". To
cope with the rapid emergence of novel biologically
active peptides, new techniques are needed to clarify
their physiological functions. Evidence is presented
here to show that antibody microinjection is a rapid
and reliable method to evaluate the functions of
endogenously released peptides. It is especially
useful when no specific receptor antagonist is yet
avaiilable for pharmacological study. 相似文献
86.
Sun Chang-ti孙昌惕 Cao Lu-cheng曹履诚and Han Ke-han韩可汉Institute of Urology Beijing Medical University Beijing 《中华医学杂志(英文版)》1987,100(12):935-939
The formation of calcium oxalate nephrolithiasis
can be estimated by measuring the concentration of
calcium oxalate versus the inhibitory role of crystal
formation in the urine. In recent studies, the
calcium oxalate saturation index and the inhibitory
activity (by modified Sarig's method) of the urine
during fasting and after oral calcium loading in
normal subjects and in patients with calcium nepliro-
lithiasis were determined. It was shown that, in
normal comrols after calcium loading the inhibitory
activity of the urine increased in parallel with the
increase in urinary excretion of calcium oxalate; in
contrast, in patients with kidney stones, it remained
unchanged or fell slightly. This abnormal response
might result in a disturbance of the saturation-inhibi-
tion balance and formation of kidney stone. In
normal individuals, there may be a "protective re-
sponse" to prevent the precipitation of calcium
oxalate when the urrine is oversaturated with calcium
oxalate while a defect of the "protective response"
in patients may be an important factor in calcium
oxalate stone formation. 相似文献
87.
Seventy three patients with disseminated diffuse non-Hodgkin's lymphomas were treated with combinations of cyclophosphamide, vincristine sulfate, prednisone, and doxorubicin with and without 2 weekly doses of oral methotrexate in "intermediate" doses, followed by calcium leucovorin rescue. The addition of methotrexate did not increase the complete remission rate, the remission duration, or the survival (P value = 1.0, 0.74, and 0.78, respectively) in patients who did not have previous chemotherapy treatment. In previously treated patients, the complete remission rate was somewhat higher and the remission duration and survival were longer among those patients treated with the methotrexate containing program; however these differences were not statistically significant (P values = 0.88, 0.81, and 0.46, respectively). There was substantial morbidity and mortality during treatment with both treatment arms, among patients aged more than 60 years. 相似文献
88.
Wong Jasin Ezeife Nnaemezie Kudla Angelika Crown Deborah Trierweiler Robert Capraro Pamela Tomazin Stephanie Su Han Pham Tri Heinemann Allen W. 《Journal of occupational rehabilitation》2022,32(3):464-472
Journal of Occupational Rehabilitation - Purpose The COVID-19 pandemic has disproportionately affected the lives of people with disabilities (PWD). How the pandemic affects the employment of PWD... 相似文献
89.
Kai Dong Mengjun Shen Guanqun Ju Sha Han Zhijun Wang Kaining Lu Dongliang Xu 《European urology》2021,79(2):283-289
BackgroundPartial nephrectomy or angioembolisation is commonly used for sporadic renal angiomyolipomas (RAMLs) with high RENAL scores, but there is a risk of reduced renal function, postoperative complications, and recurrence.ObjectiveTo describe a new technique for off-clamp laparoscopic evacuation of sporadic RAMLs with high RENAL scores that promotes maximal renal function maintenance and low postoperative complication and lesion recurrence rates.Design, setting, and participantsA retrospective cohort of patients undergoing off-clamp laparoscopic evacuation for sporadic RAMLs with RENAL scores ≥9 from January 2013 to June 2018 was included.Surgical procedureWe highlighted the curettage, suction, packing, and binding (CSPB) technique, a new off-clamp retroperitoneoscopic evacuation technique for sporadic RAMLs.MeasurementsDemographics, preoperative, intraoperative, and postoperative outcomes were assessed.Results and limitationsA total of 141 cases were included. The median (interquartile range [IQR]) tumour size was 7 (6.2–8.2) cm. The median (IQR) RENAL score was 10 (9–11). The median (IQR) operative time was 80 (65–125) min, with a median (IQR) estimated blood loss of 130 (90–362.5) ml. Conversion to neither open surgery nor standard laparoscopy occurred. The warm ischaemia time was zero for all cases. Postoperatively, 13 minor complications (Clavien grade 1) were recorded. No blood transfusions were reported. The glomerular filtration rate did not change significantly from preoperative period to 12-mo follow-up. Recurrence did not occur at the median follow-up period of 48 (36–60) mo. The retrospective design and lack of a control group are limitations of this study.ConclusionsOff-clamp retroperitoneoscopic tumour evacuation using the CSPB technique is feasible, safe, and effective for treating complex sporadic RAMLs.Patient summaryWe report a curettage, suction, packing, and binding technique for off-clamp retroperitoneoscopic evacuation of sporadic renal angiomyolipomas that leads to complete lesion clearance, excellent renal function preservation, and minimal perioperative complications. 相似文献
90.