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71.
The rheological properties of self-emulsifying systems, water and microcrystalline cellulose. 总被引:2,自引:0,他引:2
J M Newton M Bazzigialuppi F Podczeck S Booth A Clarke 《European journal of pharmaceutical sciences》2005,26(2):176-183
The rheological properties of mixtures of equal parts of a range of ratios of a self-emulsifying system (MP) and water (W) added to microcrystalline cellulose (MCC), have been measured by an extrusion capillary rheometer. These measurements allow assessment of both the shear and tension components of flow plus the elastic behaviour of the wet powder masses, although the results for the estimation of shear stress require careful interpretation due to the limitation of the measuring system and the assumptions made in their derivation. The results indicate that there are three regions of behaviour of the systems, which are all significantly different from the mixtures containing only W and MCC. At low MP contents (1.5--23%), the masses increase in their resistance to shear and elongational flow and have lower elasticity. These similarities in behaviour occur in spite of considerable increase in the viscosity of the MPW mixtures and a change to non-Newtonian flow of the fluid. The behaviour of the 46% MP system is intermediate between these systems and the high MP concentrations (69, 80 and 92%). These latter systems show less resistance to shear and elongational flow than the first group of concentrations, but show considerably higher levels of elasticity. As the resistance to shear decreases, so does the impairment of the surface of the extrudate. There is clear evidence of a systematic change in behaviour of the wet powder masses as the values for the angle of entry of the wet mass into the die when plotted against the ratio of the resistance to die entry (upstream pressure loss) to the shear stress within the die, is linear on a log/log scale. Also, the values of compliance of the systems as a function of shear stress fall on a common curve. Changes in the ratio of the MPW to MCC for a system for a single level of MP (46%) resulted in a change in the values of the rheological parameters but not the type of behaviour. As all these wet powder masses had been shown previously to form pellets by the process of extrusion/spheronization, it is clear that systems with a wide range of rheological characteristics can be processed and no single rheological parameter can be used to provide complete characterisation of the processability of such systems. 相似文献
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Charles Newton Odongo Raymond Atwine Fred Kirya Patrick Ambrose Okello Eugene Ogwang Moses Acan Felix Bongomin Martin Situma 《Clinical Case Reports》2022,10(5)
Cavernous hemangioma (CH) of urinary bladder occurs relatively infrequently, accounting for 0.6% of all bladder tumors. This tumor may occur sporadically or coexist with other benign and malignant vascular lesions. In this report, we present a rare case of CH in a 3‐year‐old Ugandan girl. A 3‐year‐old girl was referred to Mbarara Regional Referral Hospital (MRRH) for urological evaluation following a 3‐year history of intravaginal swelling, dysuria, and heavy hematuria resulting in anemia. Imaging was consistent with polypoid bladder mass arising from the bladder trigone. Embryonal rhabdomyosarcoma was suspected based on clinical eyeballing. She was worked up for chemotherapy and received 26 cycles of vincristine sulfate, actinomycin‐d, and cyclophosphamide (VAC). Biopsy and fulguration were performed after optimizing the patient. Histopathology confirmed CH. The surgery was uneventful and resulted in complete cure. CH should be considered in the differential diagnosis of childhood genitourinary masses. It is a rare entity in the real‐life clinical practice and therefore can be overlooked. Excision biopsy and histology should be performed before initiating the patients to chemotherapy. CH is very insensitive to chemotherapy and therefore surgery maybe adequate in resource‐limited settings. 相似文献
75.
Keijo Hkkinen Robert U. Newton Simon Walker Arja Hkkinen Sonja Krapi Rebekka Rekola Pivi Koponen William J. Kraemer G. Gregory Haff Anthony J. Blazevich Kazunori Nosaka Juha Ahtiainen 《Journal of Sports Science and Medicine》2022,21(2):200
Effects of eccentric (ECC) versus concentric (CON) strength training of the upper body performed twice a week for 10 weeks followed by detraining for five weeks on maximal force, muscle activation, muscle mass and serum hormone concentrations were investigated in young women (n = 11 and n = 12). One-repetition bench press (1RM), maximal isometric force and surface electromyography (EMG) of triceps brachii (TB), anterior deltoid (AD) and pectoralis major (PM), cross-sectional area (CSA) of TB (Long (LoH) and Lateral Head (LaH)) and thickness of PM, as well as serum concentrations of free testosterone, cortisol, follicle-stimulating hormone, estradiol and sex hormone-binding globulin were measured. ECC and CON training led to increases of 17.2 ± 11.3% (p < 0.001) and 13.1 ± 5.7% (p < 0.001) in 1RM followed by decreases of -6.6 ± 3.6% (p < 0.01) and -8.0 ± 4.5% (p < 0.001) during detraining, respectively. Isometric force increased in ECC by 11.4 ± 9.6 % (p < 0.05) from week 5 to 10, while the change in CON by 3.9±6.8% was not significant and a between group difference was noted (p < 0.05). Maximal total integrated EMG of trained muscles increased only in the whole subject group (p < 0.05). CSA of TB (LoH) increased in ECC by 8.7 ± 8.0% (p < 0.001) and in CON by 3.4 ± 1.6% (p < 0.01) and differed between groups (p < 0.05), and CSA of TB (LaH) in ECC by 15.7 ± 8.0% (p < 0.001) and CON by 9.7 ± 6.6% (p < 0.001). PM thickness increased in ECC by 17.7 ± 10.9% (p < 0.001) and CON by 14.0 ± 5.9% (p < 0.001). Total muscle sum value (LoH + LaH + PM) increased in ECC by 12.4 ± 6.9% (p < 0.001) and in CON by 7.1 ± 2.9% (p < 0.001) differing between groups (p < 0.05) and decreased during detraining in ECC by -6.5 ± 4.3% (p < 0.001) and CON by -6.1 ± 2.8% (p < 0.001). The post detraining combined sum value of CSA and thickness was in ECC higher (p < 0.05) than at pre training. No changes were detected in serum hormone concentrations, but baseline free testosterone levels in the ECC and CON group combined correlated with changes in 1RM (r = 0.520, p < 0.016) during training. Large neuromuscular adaptations of the upper body occurred in women during ECC, and CON training in 10 weeks. Isometric force increased only in response to ECC, and total muscle sum value increased more during ECC than CON training. However, no changes occurred in serum hormones, but individual serum-free testosterone baseline concentrations correlated with changes in 1RM during strength training in the entire group. Both groups showed significant decreases in neuromuscular performance and muscle mass during detraining, while post detraining muscle sum value was only in ECC significantly higher than at pre training. Key points
- Maximal eccentric and concentric strength training in women for 10 weeks (only twice a week) led to great gains in dynamic strength of upper body.
- Upper body muscle mass increased more after eccentric than concentric strength training.
- During detraining for 5 weeks both groups showed decreases in strength and muscle mass.
- However, post-detraining combined sum muscle mass value was only in ECC higher than at pre-training.
76.
The effect of aminophylline on renin release from human chorion was investigated by perfusing the tissue with various concentrations of the drug. Buffer containing aminophylline (2 X 10(-6) mol/l) doubled the rate of active and total renin secretion, but a more concentrated solution (10(-5) mol/l) released proportionately less active and total renin although the result was statistically significant. Renin secretion was not altered by aminophylline (5 X 10(-5) mol/l). The pattern of renin release was modulated by concentrations of aminophylline which were at least a 100-fold lower than those required to inhibit cyclic adenosine 3',5'-monophosphate phosphodiesterase. However, as the methylxanthines are potent adenosine receptor antagonists, we suggest that in the human chorion adenosine is a mediator of renin release. 相似文献
77.
Penetration of imipenem into human aqueous and vitreous humor 总被引:2,自引:0,他引:2
J L Axelrod J C Newton R M Klein R L Bergen M Z Sheikh 《American journal of ophthalmology》1987,104(6):649-653
Twenty-five patients about to undergo cataract surgery and ten patients about to undergo vitrectomy received a 1-g intravenous dose of imipenem before surgery. Specimens of aqueous or vitreous humor were then obtained and assayed for antibiotic content with a microbiologic disk agar technique. A mean peak aqueous humor level of 2.99 micrograms/ml was found at approximately two hours after administration, and a mean vitreous level of 2.53 micrograms/ml was found from two hours to three hours 15 minutes after administration. These concentrations were well above the minimum inhibitory concentration of imipenem for 90% (MIC90) of Staphylococcus epidermidis, S. aureus, and the Enterobacteriaceae commonly involved in bacterial endophthalmitis. 相似文献
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NG da Silva AS Carreira EN Pedreira FM Tuji KL Ortega JD Pinheiro 《Head & face medicine》2012,8(1):23
ABSTRACT: Central giant cell lesions are benign intraosseous proliferative lesions that have considerable local aggressiveness. Nonsurgical treatment methods, such as intralesional corticosteroid injections, systemic calcitonin and interferon have been reported. Recently, bisphosphonates have been used to treat central giant cell lesions. A case of a 36-year-old male with a central giant cell lesion crossing the mandibular midline was treated with intralesional corticosteroids combined with alendronate sodium for the control of systemic bone resorption. The steroid injections and the use of bisphosphonates were stopped after seven months when further needle penetration into the lesion was not possible due to new bone formation. After two years, the bony architecture was near normal, and only minimal radiolucency was present around the root apices of the involved teeth. The patient was followed up for four years, and panoramic radiography showed areas of new bone formation. Thus far, neither recurrence nor side effects of the medication have been detected. 相似文献