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81.
Background: This study was carried out to determine the effects of pilocarpine on the anterior chamber angle in healthy volunteers. Methods: We measured changes in anterior chamber depth (ACD), trabecular-iris angle (TIA), angle opening distance at 250 and 500 m from the scleral spur (AOD250 and AOD500), and iris thickness using ultrasound biomicroscopy in 48 eyes of 48 normal volunteers (ages 18–57 years, mean 34.8 years) before and 1 h after instillation of 2% pilocarpine. Results: Pilocarpine altered the TIA by –18.6° to + 10.5° (mean –4.16°), and change in the TIA increased significantly and linearly in relation with decrease in the pretreatment TIA (r = 0.929). Pilocarpine altered AOD250 change by –136 to +94 m (mean –38 m) and AOD500 by –151 to +157 m (mean –42 m); changes in the AOD250 and AOD500 were significantly correlated to the pretreatment AOD250 and AOD500 values, respectively (r = 0.923 andr = 0.896, respectively). The pilocarpine-induced change in the ACD showed a linear relationship to the pretreatment ACD (r = 0.887). The changes in the TIA, AOD250 and AOD500 showed greater increases in association with lower pretreatment ACD (r = 0.848,r = 0.891,r = 0.842) and smaller change in the ACD (r = 0.834,r = 0.839,r = 0.812). Conclusions: The response of the anterior chamber angle to pilocarpine, narrowing or widening, depended on its pretreatment state. The ability to predict the pilocarpine-induced change in the angle before the instillation of pilocarpine would be helpful in treating patients with glaucoma.  相似文献   
82.
All C-H and O-H bond dissociation enthalpies (BDE's) in catechins, (-)-epigallocatechin) were calculated by semi-empirical molecular orbital calculation using the SPARTAN program. The BDE's of benzyl hydrogens (C-2 position in catechins) were found to be quite low. This suggests that abstraction of benzyl hydrogen is crucial step for antioxidative activity. This is corroborated by the reported results of LC/MS and spectrophotometric analysis of reaction intermediates from catechins treated with AAPH.  相似文献   
83.
Akiyama H  Mori H  Saido T  Kondo H  Ikeda K  McGeer PL 《Glia》1999,25(4):324-331
Diffuse amyloid beta-protein (Abeta) deposits with numerous glial cells containing C-terminal Abeta fragments occur in the cerebral cortex of patients with Alzheimer's disease. By using a panel of antibodies specific for various epitopes in the Abeta peptide, we have investigated the immunohistochemical nature of the diffuse Abeta deposits. The extracellular material contains Abeta with a C-terminus at residue valine40 (Abeta40) as well as residues alanine42/threonine43 (Abeta42). The N-termini include aspartate1, pyroglutamate3, and pyroglutamate11, with pyroglutamate3 being dominant. Microglia and astrocytes in and around these deposits contain intensely staining granules. Most of these granules are negative for antibodies to the N-terminally located sequences of Abeta. These include 6E10 (Abeta1-17), 6F/3D (Abeta8-17), and the N-terminal antibodies specific to aspartate1, pyroglutamate3, and pyroglutamate11. The C-termini of intraglial Abeta are comparable with those of the extracellular deposits. The microglia and astrocytes have quiescent morphology compared with those associated with senile plaques and other lesions such as ischemia. Complement activation in these deposits is not prominent and often below the sensitivity of immunohistochemical detection. Although factors which may cause this type of deposit remain unclear, lack of strong tissue responses suggests that these deposits are a very early stage of Abeta deposition. They were found only inconsistently and were absent in a number of cases examined in this study. Further analysis of these deposits might provide important clues regarding the accumulation and clearance of Abeta in Alzheimer's disease brain.  相似文献   
84.
85.
Tsujitani S  Oka S  Saito H  Kondo A  Ikeguchi M  Maeta M  Kaibara N 《Surgery》1999,125(2):148-154
BACKGROUND: Less invasive treatment is the current trend in many surgical fields. Most patients with early gastric cancer do not have lymph node metastasis. Thus extensive resection of the stomach and extended lymph node dissection do not appear to be necessary. METHODS: In a retrospective study, 890 consecutive patients with early gastric cancer who had undergone standard gastrectomy were assessed for depth of invasion, gross appearance, and maximum diameter of the tumor to examine the possibility of limiting the extent of lymph node dissection. A variety of limited gastrectomies have been developed and now include endoscopic mucosal resection, wedge resection, segmental gastrectomy, limited proximal gastrectomy, and distal hemigastrectomy. RESULTS: A retrospective study revealed that extensive lymph node dissection did not improve the survival of patients with early gastric cancer. Endoscopic mucosal resection was suitable for cancers of the depressed type of less than 1 cm in diameter and the elevated type of less than 2 cm in diameter. Wedge, segmental, or limited proximal gastrectomy was suitable for the elevated type of 2 to 3 cm in diameter. The elevated type of more than 3 cm in diameter and the depressed type of 1 to 3 cm in diameter sometimes involved metastasis to group 1 nodes. The depressed type of more than 3 cm in diameter sometimes involved metastasis to group 2 nodes. Thus such cases should be treated by gastrectomy with dissection of potentially metastatic lymph nodes. CONCLUSIONS: Limitation of the extent of gastrectomy and lymph node dissection may be possible, depending on the gross appearance and size of the tumor.  相似文献   
86.
PURPOSE: The purpose of this study is to statistically analyze medical and socioeconomic factors which influence discharge disposition from a stroke unit. METHODS: We investigated 126 stroke patients admitted to a community hospital within 30 days from the onset of the stroke. Mean age was 65.9 +/- 13.9 (SD) years old, profile of diagnosis was 89 infarctions was 37 hemorrhages, and mean length of stay was 79.7 +/- 45.1 days. Our rehabilitation team consists of doctors, nurses, physical therapists, occupational therapists and a medical social worker. Our stroke unit accepted the stroke patients from the time of admission and attempted to begin rehabilitation as soon as possible. The patients and their families were informed about their options after discharge from the hospital. Eight factors were analyzed using a multiple logistic regression model. RESULTS: 1) Ninety-eight patients (77.8%) could return home (home group) and 28 patients (22.2%) were discharged to another hospital or a long-term care facility (LTCF group). 2) Mean age of LTCF group (70.3 +/- 12.0) was significantly higher than the home group (64.8 +/- 14.2, p < 0.05). The home group showed milder leg paresis (p < 0.01), better Barthel index (p < 0.01), a higher number of family members (p < 0.05), and a better substantial care ability (p < 0.01) than LTCF group. 3) Three factors, higher Barthel index (odds ratio: 1.36), higher number of family members (1.84), and better substantial care ability (1.94), were found to facilitate discharge to home. Two other factors, hemorrhage (0.39) and public assistance (0.04), adversely affected the likelihood of discharge to home. CONCLUSIONS: This study suggests that a stroke unit could accelerate discharge home by improving the Barthel index. In addition, socioeconomic factors should be taken into consideration.  相似文献   
87.
This study investigates the pharmacokinetics and safety profile of Z-321, (4R)-3-(indan-2-ylacetyl)-4-(1-pyrrolidinyl-carbonyl)-1,3-thiazoli dine, a novel specific orally active prolyl endopeptidase (PEP) inhibitor. Following a preliminary safety evaluation wherein 2 subjects received 3.75 and 15 mg doses and 2 other subjects received 7.5 and 30 mg doses, 16 subjects were assigned to two groups of 8 subjects each. In each group, 6 subjects were to receive active treatment, and 1 or 2 subjects were to receive placebo treatment. One group received 60 mg under fasted and fed conditions. A separate group of 8 subjects received 60 mg of Z-321 or a placebo in a bid regimen for 6 days and the morning dose on day 7. The concentrations of Z-321 and its main metabolites--R- and S-sulfoxide; RR-, SS-, and RS-indanol; and indanolsulfoxides in plasma and urine--were determined by the HPLC method. In the multiple-dose study, the cholinesterase activity was gradually increased and reached above the normal range on day 8 in 3 of 6 subjects given Z-321 and gradually returned to the normal range after completion of dosing. The elevation of plasma cholinesterase activity was considered to be an action of Z-321, but this remains to be verified. In a single-dose study at a dose of 30 mg, headache and vomiting were observed in 1 of 6 subjects. In the multiple-dose study, slight skin itching and eczema in 3 and 2 of 6 subjects, respectively, and headache in 2 of 6 subjects were observed, but all symptoms were not severe. There were no other abnormal findings in objective signs and laboratory findings, including blood pressure, heart rate, electrocardiogram, body temperature, hematology, blood chemistry, and urinalysis. The Cmax of Z-321 at 30, 60, and 120 mg in the fasting state were 63.7 +/- 23.9, 102.0 +/- 43.1, and 543.3 +/- 437.0 ng/ml (mean +/- SD), respectively, at 0.9 hours after administration, and the t1/2 was about 1.8 hours. There were no dramatic changes in the pharmacokinetics of Z-321 in the presence of food. In the multiple-dose study, there was no drug accumulation trend in plasma. These results indicate that Z-321 has acceptable pharmacodynamic and pharmacokinetics profiles for clinical use without any serious adverse events, as verified in healthy young male volunteers.  相似文献   
88.
The von Hippel-Lindau (VHL) tumor suppressor gene has been shown to be mutated frequently not only in neoplasms from von Hippel-Lindau disease, but also in sporadic clear cell renal carcinoma. In order to reveal the possible role of the VHL tumor suppressor gene in the development of ovarian carcinoma, a total of 71 primary sporadic ovarian carcinomas were analyzed for the presence of mutations in the exon 2 and 3 of the VHL tumor suppressor gene, using the polymerase chain reaction with single strand conformation polymorphism analysis. No mutations in the VHL gene were found in any of the tumors analyzed. This result shows that the VHL tumor suppressor gene does not play a major role in the tumorigenesis of sporadic ovarian carcinoma.  相似文献   
89.
Summary The basiparallel cut is a nearly horizontal slice of the posterior fossa used in air study and the structures are observed on a plane parallel to the clivus. Total shrinkage of the cerebellum, with or without fourth ventricle dilatation, was found in cases of olivopontocerebellar atrophy, some intoxications, and a few senile subjects. Some atrophy of paleocerebellar portions was seen in Holmes-type degeneration. Another pattern was symmetric shrinkage of neocerebellar lobules and relatively specific for the cases of multiple system atrophy such as progressive supranuclear palsy, striatonigral degeneration, Marie's ataxia, etc. Loss of the superior cerebellar peduncle was clearly demonstrated in this view.  相似文献   
90.
The cytotoxicity of two types of nickel oxide particles was investigated in rat alveolar macrophages cultured in vitro. The trypan blue dye exclusion test and the release of lactate dehydrogenase into culture medium were used as cytotoxic indices. Although both types of nickel oxide particles were produced by the same manufacturer and were commercially sold under the same name of "nickel oxide", one type of the nickel oxide particles which had black color was much more cytotoxic than the other type of green color. The black nickel oxide particles were more soluble in various kinds of solutions than the green nickel oxide particles. Therefore, it appears that the difference in the cytotoxicity of the black and green nickel oxide particles may be attributable to the difference in the solubility of the particles.  相似文献   
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