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31.
Skoug John W. Borin Marie T. Fleishaker Joseph C. Cooper Anne M. 《Pharmaceutical research》1991,8(12):1482-1488
The mechanism of release from sustained-release adinazolam mesylate tablets was assessed by the Higuchi equation and by analysis of drug release profiles through 60% released using the Peppas equation. Computed values of the diffusional exponent, n, ranged from 0.59 to 0.66. Values of n in this range are consistent with a mixed mechanism of release, with diffusion of drug through the hydrated polymer matrix and relaxation of this matrix being the principal processes controlling release. The rate of in vitro drug release was increased for half tablets relative to whole tablets and is attributed to an increase in the surface to volume ratio of half tablets of about 16%. This increase in surface-to-volume ratio of half tablets was reflected by an increase in the constant, k, from the Peppas equation of 20–23% and by an increase in the slope of Higuchi plots of 12–18% for four lots of tablets. In vivo/in vitro relationships from two bioavailability studies were thoroughly evaluated. Using either a linear or a quadratic relationship, an in vivo/in vitro correlation exists for sustained-release adinazolam mesylate tablets. 相似文献
32.
C. COLETTE M. C. GOUTTEBEL† L. H. MONNIER B. SAINT-AUBERT† H. JOYEUX† 《European journal of clinical investigation》1986,16(4):271-276
Seventeen patients who had undergone extensive small bowel resection were studied for calcium absorption (FACa) and plasma vitamin D metabolites. FACa was measured by a double radio-tracer technique and expressed as percentage of total oral dose. FACa was decreased compared with controls (34%, range: 3-46 v 65%, range: 57-73, P less than 0.01). A positive correlation (r = 0.49, P = 0.05) was found between FACa and the remaining length of small bowel (SBL). As wide variations in both SBL and duration after surgery were observed among the seventeen investigated patients, we were led to individualize less heterogeneous subgroups of patients. Better correlations were found when the patients were divided into two subgroups according to whether the time interval between the resection and the investigation was shorter (r = 0.75, n = 11, P less than 0.02) or longer (r = 0.89, n = 6, P = 0.05) than 2 years. In thirteen patients who had a SBL shorter than 100 cm, a positive correlation was observed between FACa and the time interval after surgery (months): r = 0.65, P less than 0.05. Plasma 1,25 (OH)2D was markedly reduced in the whole group (31 pmol l-1, range: 8-108) compared with controls (103 pmol-1, range: 59-134, P less than 0.01). The present study shows that in extensively small bowel resected patients, calcium absorption is reduced, the alteration being dependent both on the length of the remnant small bowel and on the time after surgery.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
33.
Urvashi Razdan R. M. Raizada V. N. Chaturvedi 《Indian journal of otolaryngology and head and neck surgery》2004,56(1):20-22
Objective To assess the efficacy of conservative modalities in the management of epistaxis.
Study design Prospective case studies.
Setting Rural medical college hospital.
Patients Indoor and outdoor patients with epistaxis.
lntervention Conservative(non surgical) management techniques in epistaxis.
Results Chemical cauterization was successful in 72.07% cases, anterior nasal packing in 84.5% and posterior nasal packing in 95.6%
cases.
Conclusion Out of 300 cases of epistaxis included in the study (except for one case that required internal maxillary artery ligation).
all cases were treated successfully with conservative treatment alongwith treating the underlying pathology causing epistaxis. 相似文献
34.
A. Ravikumar S. Mohanty R. P. Vatsanath S. Raghunandhan 《Indian journal of otolaryngology and head and neck surgery》2004,56(4):317-320
The co-existence of fungal elements in allergic nasal Polyposis, has given rise to a distinct clinical entity known as ‘Allergic
fungal sinusitis ’ (AF’S). Many a time, these fungal elements may not be diagnosed pre-operatively by routine diagnostic nasal
endoscopy or CT scan of paranasal sinuses, due to the florid presentation of nasal polyps, which usually obscure the underlying
fungal pathology. The diagnosis is often made intra-operatively. The post-operative confirmation of AFS is by histopathology,
fungal smear, fungal culture, allergic murin study and fungal specific IgE titres. We report a series often such cases done
in our institution, which highlight that AFS should be considered as a differential diagnosis in Sinonasal Polyposis cases,
for their effective management. 相似文献
35.
本文通过分析鼻骨外伤X线成像特点,重点探讨了常规X线与DR检查在鼻骨外伤中的应用价值,旨在提高对鼻骨骨折诊断的准确率。结果表明DR摄影是鼻骨常规检查的理想手段。 相似文献
36.
亚低温治疗患者鼻饲营养并发症的观察及护理 总被引:4,自引:1,他引:3
报道48例亚低温治疗患者采用一次性投给、间歇滴注和连续输注营养膳的方式鼻饲营养,其并发症有:腹泻、腹胀、肠蠕动亢进,便秘,食物反流,吸入性肺炎,代谢紊乱,高血糖,水、电解质失衡,鼻胃管堵塞等。护理中体会到亚低温治疗患者鼻饲营养的时机最好在急性期1~2d后,应用鼻饲泵连续输注,适时使用胃肠动力药西沙比利.掌握营养膳的配制和正确的鼻饲方法,严密观察,发现异常及时处理,可大大降低并发症的发生。 相似文献
37.
目的探讨间接喉镜下或鼻内镜下微波热凝治疗声带息肉或小结的效果。方法对321例在间接喉镜或鼻内镜下微波热凝治疗声带息肉或小结病例资料进行分析。结果321例患者均一次手术成功。术后随诊3个月~一年以上的321例患者,治愈率92%,好转率8%。无效率为0。术中和术后未发生并发症。结论间接喉镜下或鼻内镜下微波热凝治疗声带息肉声带小结,具有操作安全、方便、不出血、快捷、简单、治愈率高等优点。 相似文献
38.
Lage Burström Ronnie Lundström 《International archives of occupational and environmental health》1988,61(3):213-216
Summary A possible basis for risk assessment of human exposure to vibration when using hand-held tools may be to determine the amount of mechanical energy that is absorbed by the hand-arm system. The aim of this investigation was to study the absorption of mechanical energy in the human hand-arm system during exposure to sinusoidal vibration within the frequency range of 20 to 1500 Hz. A handle, specially designed for this type of experiments, was used during the measurements. The influence of various experimental conditions, such as three different hand-arm postures, grip force (25–75 N) and vibration levels (27–53 mm/srms), were studied on eight subjects. The outcome clearly shows that the energy absorption properties of the human hand-arm system are more or less dependent on all of the experimental conditions studied, but mainly to the frequency of the vibration stimuli. Furthermore, the results indicate a non-linear relationship between the energy absorbed and all other variables studies. 相似文献
39.
复方18甲基炔诺酮/雌二醇透皮控释传递系统(LNG/E_2 TCDS)能同时恒速释放低剂量的LNG和E_2,在1周内维持一个平稳而有效的LNG血药浓度。药动学与药效学研究证明,该系统释放的LNG能达到血清LNG目标水平,产生有效的排卵抑制(6/6)。LNG/E_2 TCDS可望发展成为一种安全、有效、非侵入性的新型生育调节避孕制剂。 相似文献
40.
A case of a 14 month old Japanese female infant presenting with nasal glioma Is reported. The tumor had been noticed at the nasal radix since birth and had slowly and progressively enlarged. There was no communication between the tumor and the cranial cavity on radiological examination. The tumor was macroscopically anchored to the nasal septum by a fibrous stalk, and histologically consisted of nests or trabeculae of either polygonal or spindle cells with plump eosinophilic cytoplasm and oval nuclei, separated by vascular-rich connective tissue intermingled with multinu-cleated giant cells. These tumor cells were immunohisto-chemically positive for glial fibrillary acidic protein as well as for S-100 protein and vimentin. An electron microscopic examination revealed collagen fibers and basal lamina between the tumor cells and the fibroblasts. Tumor cells possessed abundant intermediate filaments, which showed occasional Rosenthal fiber-like structures, in their cytoplasm and processes. A few oligodendrocytes and cilia of 9 micro-tubule doublets either with or without 2 central microtubules were also noted. These clinicopathological findings suggested that this tumor was once an encephalo(meningo)cele, which probably degenerated as a result of the loss of intracranial communication and then appeared to be isolated from the intracranial tissue. 相似文献