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131.
The fate (movement and disintegration) of hard novel hydroxypropyl methylcellulose (HPMC) two-piece capsules in the human gastrointestinal tract was investigated using a gamma scintigraphic imaging method. Two different prolonged-release formulations without an active ingredient were used. The capsules contained different viscosity grades of HPMC powder (HPMC K100 and HPMC K4M). The aim was to determine the main reason why the pharmacokinetic profiles of model drugs change when the diluent was changed to a higher viscosity grade. The results were compared with our previous pharmacokinetic studies with corresponding capsules containing metoclopramide hydrochloride or ibuprofen as a model drug. The first observation was that the HPMC capsules had a tendency to attach to the oesophagus. Therefore, it is recommended that the HPMC capsules as well as gelatine capsules be taken with a sufficient amount of water (150–200 ml) in an upright position and maintaining the upright position for several minutes. The viscosity grade of the HPMC did not affect the transit times of the capsules in the GI tract. The major differences between the two formulations were the complete disintegration times of the capsules and the spreading of the capsules to the large intestine. Most of the HPMC K100-based capsules were completely disintegrated during the 8 h study, whereas the HPMC K4M-based capsules still exhibited plug formations in the large intestine. Also the HPMC K100-based capsules spread better to the ascending colon than the HPMC K4M-based capsules. The faster disintegration of the HPMC K100-based capsules explains the differences in the pharmacokinetic profiles of the model drugs between the HPMC K100- and K4M-based capsules in our previous studies. The main absorption site of the drugs from the capsules studied here is probably the large intestine when taken in a fasting state.  相似文献   
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133.
The aim of this study was to describe the dynamics of HIF‐1α, GLUT‐1, Bcl‐2 and Ki‐67 during chemoradiotherapy (CRT) of rectal cancer, and to investigate the fluctuation of these biomarkers in relation to pathological response to CRT. The study included 86 patients with rectal adenocarcinoma receiving preoperative CRT (>50.4 Gy and Uracil/Tegafur). Immunohistological expressions of HIF‐1α, GLUT‐1, Bcl‐2 and Ki‐67 were investigated in biopsies taken before treatment, after 2, 4 and 6 weeks of CRT and in specimens from the operation. Decreasing expressions of HIF‐1α, Bcl‐2 and Ki‐67 were observed during CRT, whereas GLUT‐1 overall was unchanged. No significant changes of the markers were observed in the interval between CRT and surgery. A significant association was observed between the presence of residual carcinoma after 6 weeks of treatment and pathological response to CRT, but no association was seen between the fluctuations of any of the markers and response to CRT. This unique material containing specimens before, after and during CRT for rectal cancer demonstrated biological dynamics in HIF‐1α, Bcl‐2 and Ki‐67, but not GLUT‐1, expression during CRT, and a significant association was seen between the presence of residual carcinoma after 6 weeks of treatment and pathological response to CRT.  相似文献   
134.
Adult‐onset inflammatory linear verrucous epidermal nevus (ILVEN) is an uncommon cutaneous disease compared to childhood‐onset ILVEN. The typical histopathologic features are alternating parakeratosis and orthokeratosis with an absent granular layer underneath parakeratosis, in contrast to a thickened granular layer below the foci of orthokeratosis in psoriasiform epidermal hyperplasia. Herein, we present a 49‐year‐old woman with typical clinical and histopathologic characteristics of adult‐onset ILVEN, including linear arrangement of thick scaly papules and plaques localized on the medial side of her right leg, ankle, and foot. Immunohistochemical studies included involucrin, Ki‐67, and keratin‐10. Compared to the staining pattern in psoriasis, the expression of involucrin in this case was of lower intensity and localized to upper epidermal layers with relatively less extensive staining beneath regions of parakeratosis as compared to orthokeratosis; Ki‐67 showed lower basal layer proliferative activity; and keratin‐10 showed a greater intensity of staining within suprabasal epidermis.  相似文献   
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136.
Mantle Cell lymphoma is a heterogeneous malignancy that has different subtypes with variable levels of aggressiveness. Research on the pathobiology of this disease is helping us understand the etiology for this heterogeneity and has the potential to guide future therapeutic options. The availability of the Ki67 proliferation index and the use of the MIPI score can help determine which of the numerous therapeutic options might be utilized. Minimal Residual Disease testing can act as a guide as to the potential benefit of maintenance therapy. This article discusses the current standard of care for Mantle Cell lymphoma and our current understanding of the pathobiology of the disease leading to strategies to improve patient outcomes with some of the newer targeted agents.  相似文献   
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138.
Abstract

We report a case of nodular-type muscular sarcoidosis with no systemic symptoms. Thallium-201 scintigraphy showed intense uptake in the muscular lesion mimicking malignant soft tissue tumor. Magnetic resonance imaging (MRI) demonstrated characteristic signal patterns of peripheral high intensity with central low intensity (“three stripes” pattern). Microscopy revealed sarcoid granuloma with typical histopathological characteristics. Propionibacterium acnes was detected on polymerase chain reaction analysis of the excised tissue.  相似文献   
139.
《Acta orthopaedica》2013,84(3):380-385
Background?There are few dual X-ray absorptiometry (DXA) studies on periacetabular bone density changes after cup implantation. This study was designed to analyze the load-transfer mechanism and stress pattern of periacetabular cortical and cancellous bone after implantation of a ihemispherical titanium alloy press-fit cup with alumina-alumina pairing in vivo. We introduced a novel method of computed tomography (CT)-assisted osteodensitometry.

Method?We investigated 26 hips (26 patients) with osteoarthritis using conventional sequential CT examinations performed within the first 10 days after implantation, and after a mean period of 1.1 years postoperatively. Bone density of full, cancellous and cortical bone (mgCaHA/mL) was measured.

Results?At the time of follow-up, the mean bone density values of the cortical bone cranial to the cup increased by 3.6% (p = 0.03) while the cancellous bone density decreased by 18%. Cancellous bone loss was greater in the region ventral to the cup (–35%) than in the dorsal region (–30%). Cortical bone density decreased ventral to the cup (–6.4%). All these changes were statistically significant. The bone density changes in the dorsal cortical region were not significant.

Interpretation?The method presented is an excellent tool for detailed measurement of bone density changes around the cup after total hip arthroplasty, and allows a thorough assessment of stress shielding phenomena in vivo. The hemispherical titanium alloy press-fit cup is a rigid implant which stress shields cancellous bone and enhances load transfer to the cranial cortical bone. Further investigations will demonstrate the impact these factors have on the long-term results of the implant, and may allow a type-related predictable prognosis of the longevity of the prosthesis.  相似文献   
140.
目的应用正常及制备的肝硬化大鼠模型的肝脏组织观察H2S过载及不足状态下肝细胞的增殖变化。方法雌性SD大鼠48只,随机分为6组(每组8只):NF组(正常对照组)、SF组(正常H2S增加组)、PF组(正常H2S减少组)、HF组(肝硬化对照组)、SHF组(肝硬化H2S增加组),PHF组(肝硬化H2S减少组)。分组比较门静脉压力及门静脉血浆H2S含量,免疫组化法观察CSE及Ki-67的表达,免疫荧光双重染色观察CSE及Ki-67是否在同一细胞表达。结果随着给予H2 S供体及H2 S的抑制剂,HF组H2S含量明显低于NF组(P<0.01),SHF组和SF组中,给予H2S供体均能使H2S含量升高(P<0.01),给予H2S供体使H2S含量进一步升高(P<0.01);HF组CSE表达明显低于NF组(P<0.01),SF组H2S表达较SHF组均减少(P<0.01)。H2S对正常大鼠无明显作用;HF组Ki-67表达明显高于NF组(P<0.01),SF组H2S表达较SHF组增加(P<0.01),Ki-67表达在正常大鼠无明显作用。结论 NaHS作为H2S供体可能具有抑制实验性肝硬化大鼠肝组织内细胞增殖的作用,H2S可能通过抑制星状细胞和肝血管平滑肌细胞从而对肝硬化起到保护作用。  相似文献   
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