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51.
Rate and association constants (k and K) for the addition of sulfite ions to five nicotinamides substituted at the ring nitrogen, ( 2a–e ), and to poly(1-(4-vinylbenzyl)nicotinamide chloride) (poly{1-[4-(3-aminocarbonylpyridiniomethyl)phenyl]ethylene chloride}) (poly( 1 )) were determined at 30°C in aqueous systems. It was found that the reaction parameters for the addition of SO to poly( 1 ) are markedly enhanced (20500-fold in the k term and 510-fold in the K term) compared with the addition to the corresponding monomeric compound, 3-aminocarbonyl-1-benzylpyridinium chloride ( 2d ), and the enhancements are suppressed with increased ionic strengths. These enhanced reaction parameters for poly( 1 ) are deviated to the upper area by two logarithmic units from a linear log K vs. logk relationship which holds for monomeric nicotinamides. This means that the rate constant is enhanced more effectively that the association constant in the polymeric system. Plots of log KCN? vs. log K and of log kf, CN- vs. log k- gave good linear relationships. The plot for poly( 1 ), greatly deviated again to the upper area. The SO ion interacts with poly( 1 ), a cationic polyelectrolyte, more strongly than the CN? ion. 相似文献
52.
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
53.
Ndembi N Takehisa J Zekeng L Kobayashi E Ngansop C Songok EM Kageyama S Takemura T Ido E Hayami M Kaptue L Ichimura H 《Journal of acquired immune deficiency syndromes (1999)》2004,37(5):1641-1650
To monitor the presence of genotypic HIV-1 variants circulating in eastern Cameroon, blood samples from 57 HIV-1-infected individuals attending 3 local health centers in the bordering rural villages with Central African Republic (CAR) were collected and analyzed phylogenetically. Out of the 40 HIV-1 strains with positive polymerase chain reaction (PCR) profile for both gag and env-C2V3,12 (30.0%) had discordant subtype or CRF designation: 2 subtype B/A (gag/env), 1 B/CRF01, 2 B/CRF02, 1 CRF01/CRF01.A, 2 CRF11/CRF01, 1 CRF13/A, 1 CRF13/CRF01, 1 CRF13/CRF11, and 1 G/U (unclassified). Twenty-eight strains (70.0%) had concordant subtypes or CRF designation between gag and env: 27 subtype A and 1 F2. Out of the remaining 17HIV-1 strains negative for PCR with the env-C2V3 primers used, 10 (58.8%) had discordant subtype or CRF, and 7 (41.2%) had concordant one based on gag/pol/env-gp41 analysis. Altogether, a high proportion (22/57, 38.6%) of the isolates were found to be recombinant strains. In addition, an emergence of new forms of HIV-1 strains, such as subtype B/A (gag/env), B/CRF01 and B/CRF02, was identified. The epidemiologic pattern of HIV-1 in eastern Cameroon, relatively low and high prevalence of CRF02 and CRF11, respectively, was more closely related to those of CAR and Chad than that of other regions of Cameroon, where CRF02 is the most predominant HIV-1 strain. These findings strongly suggest that this part of Cameroon is a potential hotspot of HIV-1 recombination, with a likelihood of an active generation of new forms of HIV-1 variants, though epidemiologic significance of new HIV-1 forms is unknown. 相似文献
54.
55.
Seiji Miyauchi Yuichi Sugiyama Yasufumi Sawada Kaname Morita Tatsuji Iga Manabu Hanano 《Journal of pharmacokinetics and pharmacodynamics》1987,15(1):25-38
Hepatic elimination of 4-methylumbelliferone (4MU), which has been used as a model compound for conjugative metabolism, was studied by means of a multiple indicator dilution (MID) method in the isolated perfused rat liver. Using this method, three intrinsic hepatic clearances, CL
int,inf
, CL
int,eff, and CL
int,seq, which represent the influx, efflux, and sequestration processes, respectively, were obtained. When the dose was increased from a low dose (50 g/rat liver) to a high dose (3000 g/rat liver), the hepatic availability of 4MU increased from 0.11 to 0.73. With increasing dose, the CL
int,eff value increased approximately two times, while the CL
int,seq value decreased to approximately one-third. The remarkable dose dependence of hepatic availability was due to nonlinearity in both CL
int,eff and CL
int,seq values. However, the CLint,inf
value was almost independent of dose. The dose-dependent change in CLint,seq
might be explained by the saturation of conjugative metabolism of 4-MU, while the increase in the CL
int,eff value with increasing dose might be partly explained by the nonlinear tissue binding of 4-MU, since the tissue unbound fraction determined by an ultrafiltration method using liver homogenate increased approximately 1.5 times at higher concentration of 4-MU compared to that at lower concentrations. In addition, based on a comparison of the individual intrinsic clearances, i.e., CL
int,inf
, CL
int,eff, and CL
int,seq, the major determining process of the apparent hepatic intrinsic clearance of 4MU is thought to be the sequestration process at the high dose. However, at the low dose, the membrane transport process (influx and efflux processes) as well as the sequestration process also determine the apparent hepatic intrinsic clearance. 相似文献
56.
M Sasaki K Ono N Kawahara H Tsutsumi T Aruga H Toyooka K Mii M Tsuzuki K Takakura 《No shinkei geka. Neurological surgery》1984,12(6):673-678
Head injury patients often complicate facial and/or multiple injuries other than cranio-cerebral insults and perplex the emergency staffs. The authors used Brighton epistaxis balloon for such patients with massive nasal bleeding and reported the utility of the balloon not only in such state of emergency but also for a few days to control the hemorrhage mostly caused by craniobasal fractures or rupture of the adjacent vessels. One hundred and twenty-nine patients were transported and hospitalized in Department of Emergency Medicine, University of Tokyo Hospital, Tokyo, Japan during the period from October, 1981 to January, 1983. Nasal bleeding was noted in 29 cases of them and the balloon was used in 10 cases, who were from 19 to 76 years of age, all males and suffered from basal fractures or craniofacial injuries. Six cases of them were also accompanied with fractures in the extremities or pelvis, hemopneumothorax and/or intra-abdominal bleeding and could not but put on "Military anti-shock trousers" for the management of hypovolemic shock, hence the nasal bleeding should be managed immediately in the emergency room. In these situations the balloon was inserted into both nasal cavities in all the patients, to control successfully the nasal hemorrhages one of which contaminated cerebrospinal fluid and three of which were sure to be pulsatile due to arterial injury. The Brighton epistaxis balloon is to be removed within twelve or twenty-four hours, but in the authors' cases the mean duration for the hemostasis was 58.9 hours for 6 survivors and 49.6 hours for all 10 cases.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
57.
Naoki Nakano Seiji Kubo Yutaka Sato Koji Takayama Kiyonori Mizuno Ryosuke Kuroda Tomoyuki Matsumoto 《Indian Journal of Orthopaedics》2021,55(4):948
BackgroundMany factors have been reported to affect postoperative range of knee flexion after total knee arthroplasty (TKA); however, no study has reported the impact of preoperative range of motion of the hip to the postoperative flexion angle of the knee thus far.MethodsOf 38 consecutive patients who underwent posterior-stabilized TKA, we assessed 21 patients after excluding 17 patients who met exclusion criteria. The range of motion of the knee and the hip, age, body-mass index, serum albumin level, HbA1c, Kellgren–Lawrence grade, knee extension strength and radiological femorotibial angle as well as postoperative knee flexion angle at three months were evaluated. The preoperative data and the knee flexion angle at three months after TKA were compared using Spearman''s rank correlation coefficient.ResultsKnee flexion angle at three months after TKA was positively correlated with preoperative flexion (ρ = 0.616, p = 0.007) and external rotation angle (ρ = 0.576, p = 0.012) of the hip as well as preoperative knee flexion angle (ρ = 0.797, p = 0.001). There were no correlations between postoperative knee flexion angle and other preoperative data.ConclusionsPatients with restricted flexion and/or external rotation of the hip may have contractures of Gluteus maximus, Gluteus medius and Tensor fasciae latae, which can cause hypertension of iliotibial tract. It may cause decreased internal rotation of the tibia when the knee is flexed, which affects postoperative knee flexion angle, thus limited flexion and/or external rotation of the hip might restrict knee flexion angle following TKA. 相似文献
58.
Terue Okamura Toshiko Kobashi Joji Kawabe Hironobu Ochi Yasuto Onoyama Seiji Yamagami 《Journal of bone and mineral metabolism》1994,12(Z1):S111-S116
Renal osteodystrophy (ROD) accompanied by long-term hemodialysis patients with chronic renal failure includes several forms
of disorders of mineral and skeletal metabolism such as osteitis fibrosa attributed to secondary hyperparathyroidism, osteomalasia
and adynamic bone disease. Bone scan is performed to detect of the mainly pathophysiology of ROD. We investigated bone scan
of 25 hemodialysis patients with secondary hyperparathyroidism diagnosed clinically before and after parathyroidectomy (PTX).
Before PTX an diffusely high accumulation of bone seeking agent in the whole skeleton especially skull in all patients (100%),
vertebra in 24 out of 25 (96%), patella in 24/25 (96%), limbs in 23/25 (92%), sternum in 19/25 (76%), sacrum in 18/25 (72%)
and costochondral junctions in 14/25 (56%) was noted in these patients. The radionuclide activity of the calvaria, maxilla
and mandible in the skull was prominently high. Fourteen patients had an equally high activity in the calvaria, maxilla and
mandible, 6 patients had higher activity in the maxilla and mandible than that of calvaria and 5 patients had higher in the
calvaria than that of maxilla and mandible. After PTX the changes in the skull were obvious in 19 patients who showed a more
markedly decreased in activity of the maxilla and mandible than that of the calvaria. In 3 patients showed a more markedly
decreased in activity of the calvaria than that of the maxilla and mandible. Another 3 demonstrated equally decreased in activity
in the calvaria, maxilla and mandible. It became clear that the highest activity of the skull was shown in all patients and
the therapeutic changes of the skull are the most pronounced in maxilla and mandible in this study. 相似文献
59.
60.
Tatsuro Kono Hiroko Kurome Yuzo Shibuya Seiji Hayasaka 《Albrecht von Graefes Archiv fur klinische und experimentelle Ophthalmologie》1995,233(11):667-671
Background: Nevus of Ota is common in Japanese women, but most patients are not examined ophthalmologically. Methods: We performed ophthalmologic examinations on 16 Japanese women who had had bluish pigmentation in the periorbital region, sclera, and conjunctiva since birth. Results: Fifteen patients had unilateral involvement, and one had bilateral lesions. The visual acuities were good, and the intraocular pressures were within normal range. All patients had a negative family history. Three patients had light pigmentation in the optic disc in the affected eye. Conclusion: We believe that optic disc pigmentation associated with nevus of Ota, as found in these three patients, may be common but have been rarely described. 相似文献