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排序方式: 共有10000条查询结果,搜索用时 15 毫秒
991.
Replacement of cholesterol gallstones by murideoxycholyl taurine gallstones in prairie dogs fed murideoxycholic acid 总被引:1,自引:0,他引:1
B I Cohen N Ayyad E H Mosbach C K McSherry N Matoba A F Hofmann H T Ton-Nu Y Peng C D Schteingart R J Stenger 《Hepatology (Baltimore, Md.)》1991,14(1):158-168
The effect of two hydrophilic bile acids, murideoxycholic acid (3 alpha,6 beta-dihydroxy-5 beta-cholanoic acid) and ursodeoxycholic acid, on cholesterol and bile acid metabolism and hepatic pathology and gallstone composition was studied in the prairie dog. Cholesterol gallstones were induced by feeding a diet containing 1.2% cholesterol for 75 days. The animals were divided into six groups, and gallstone regression was studied as follows: groups 2 and 5, chow plus 0.2% cholesterol; groups 3 and 6, chow plus 0.2% cholesterol plus 0.15% ursodeoxycholic acid; groups 4 and 7, chow plus 0.2% cholesterol plus 0.15% murideoxycholic acid. Animals in groups 2 to 4 were killed after an additional 6 wk; animals in groups 5 to 7 were killed after an additional 12 wk. Gallstone dissolution did not occur in any group. The gallstones in groups 2, 3, 5 and 6 were typical cholesterol aggregates, as determined by polarized light microscopy and Fourier transform infrared spectrometry. The gallstones of the murideoxycholic acid group were large, solitary, dark stones that appeared radiopaque under 22 kVp x-ray examination. Scanning electron microscopy showed that in these stones the cholesterol crystals had been replaced by an amorphous material, both within the stone and on the stone surface. Chemical analysis indicated that at the end of 12 wk the calcium/sodium salt of the taurine conjugate of murideoxycholic acid (murideoxycholyl taurine) comprised 70% of the stones; protein, cholesterol and small amounts of other bile salts were also present. In vitro studies confirmed the insolubility of the sodium and calcium salts of murideoxycholyl taurine. These studies indicate that the hydrophilic bile acids, murideoxycholic acid and ursodeoxycholic acid, did not achieve gallstone dissolution under the conditions used. In the animals fed murideoxycholic acid, an insoluble calcium salt of murideoxycholyl taurine replaced cholesterol as the major constituent of gallbladder stones. This is the first example of an insoluble dihydroxy taurine-conjugated bile acid; administration of the unconjugated bile acid induced precipitation of a kind of gallstone not previously reported. The final result was transformation of cholesterol stones to bile salt stones. 相似文献
992.
Demetrius M Maraganore Matthew J Farrer Timothy G Lesnick Mariza de Andrade James H Bower Dena Hernandez John A Hardy Walter A Rocca 《Movement disorders》2003,18(11):1233-1239
We conducted a case-control study of the alpha-synuclein-interacting protein gene (SNCAIP, also known as synphilin-1) and Parkinson's disease (PD). A total of 319 PD cases and 195 controls were genotyped for four SNCAIP variants, including a microsatellite repeat in intron 4 and three restriction fragment length polymorphisms (RFLP) proximal to the 5' terminal of exons 1, 4, and 6. None of the variants were found associated with PD overall. Global score statistics were not significant for four, three, and two loci haplotypes. All four loci were in linkage disequilibrium for cases, controls, or both groups combined (P < 0.0001). Recursive partitioning showed no interactions between variants of the SNCAIP gene and variants of the alpha-synuclein gene (SNCA) or the parkin (PARK2) gene. 相似文献
993.
994.
995.
X F Sun H Zhang X C Wu Y M Han G Q Hou M S Xian 《Acta oncologica (Stockholm, Sweden)》1992,31(1):37-40
The microcirculatory architecture of normal tissue, transitional mucosa and adenocarcinoma of the human colon was investigated with microvascular corrosion casting (MVCC) combined with scanning electron microscopy (SEM). The study showed that the capillaries within the normal mucosa were arranged in a regular hexagonal pattern around the mucosal glands and that the microvessels of transitional mucosa mostly had lost the typical hexagonal pattern and become slightly wider in diameter. The microvessels in the tumor periphery were increased in number and disorganized, and presented large variation in morphology with claw-like formations, widened sinuses, diverticula and appendixoid patterns. Microvessels were lacking in the central areas of tumors. These morphological alterations may serve as additional indicators of tumor development. 相似文献
996.
997.
Y Muraki T Kobayashi H Kojima A Shibuya T Nagasawa T Abe N Mori 《[Rinshō ketsueki] The Japanese journal of clinical hematology》1992,33(3):328-332
A 50-year-old woman with anorexia nervosa was admitted for evaluation of neutropenia (WBC 1,600/microliters). Her bone marrow was gelatinous, and myeloid cells had decreased. Homogeneous substance deposited in the marrow, stained by alcian blue (pH 2.5), indicative of acid mucopolysaccharides. CFU-G and CFU-GM were decreased in number and myeloid pool in the bone marrow also decreased. Anti-neutrophilic antibody was negative. Neutropenia may be related to myeloid hypoplasia, due to increase of acid mucopolysaccharides replacing adipose cells in the bone marrow under long-term mal-nutritional state. Neutrophils markedly increased by administration of rhG-CSF 5.0 micrograms/kg/day for 14 days without the first peak. Serum G-CSF level did not increase (less than 60 pg/ml). It is effective to administer G-CSF to anorexia nervosa with neutropenia. 相似文献
998.
999.
Background: The qualities of visual perception and of motor reaction to the visual stimulus have never been studied in reference to the type of video-camera system (2-D vs 3-D) used during laparoscopy. Methods: The study was designed in two parts. The first evaluated the ability of the eye to discriminate how objects are spaced relative to one another. The second investigated the motor reaction to the visual stimulus in an environment where depth was the preponderent cue. The tests were performed in a pelvi-trainer in which were inserted different modules built either for visual observation (Part 1) or for evaluation of motor ability (Part 2). Variables studied during Part 1 were the time required to do the test and the number of errors committed during its performance. The variable evaluated during Part 2 was the time needed to terminate the test. Each of these two parts of the study were completed alternating the 2-D and 3-D systems. A total of 304 observations were recorded. Statistics used were the paired t-test, the independent group t-test, and the Newman-Keuls multiple comparisons test. Results: Results of Part 1 of the study confirm that visual perception varies significantly among individuals (n = 10) (p < 0.05) and that a true 3-D video-camera system facilitates visual perception when compared to a 2-D system (p < 0.001). Results of Part 2 of the study also show significant differences among participants (n= 9) (p < 0.05). The true 3-D system allowed significantly faster motor performances than the 2-D system (p < 0.001). Conclusion: Our experiment shows that the 3-D system allowed significant improvements in the execution of the evaluated parameters. Also noted were significant differences among participants in term of visual and motor skills. 相似文献
1000.
Shigeki Ohgitani Akimitsu Miyauchi Yasuyuki Takagi Yoshio Fujii Takuo Fujita Misa Nakamura Zhi-qiang Zhang Liang Shan Mitsuyo Sasaki Ryuichi Tsukino Toyoharu Yokoi Kennichi Kakudo Tomitaka Nakayama Junya Toguchida Hiroshi Kanoe Shinichi Aizawa Masao S. Sasaki Takashi Nakamura M. Suda K. Tanaka Y. Ogawa N. Tamura A. Yasoda H. Itoh M. Uehira N. Nishimoto T. Takigawa K. Shiota K. Nakao 《Journal of bone and mineral metabolism》1997,15(3):165-171