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61.
PURPOSE: Flavonoids with two to five hydroxy groups, with or without sugar, and/or methoxy groups were studied on their effects to affect ocular blood flow. METHODS: Colored microsphere technique was used to determine the ocular blood flow in rabbit eyes. RESULTS: Flavonoids with three free hydroxy (OH) groups seemed to produce the optimal effects in increasing ocular blood flow (naringenin and hesperitin, Pfalts and Bauer, Waterbury, CT). Whether the OH groups are below three (naringenin, hesperitin, Pfalts and Bauer, Waterbury, CT) or above four (Quercetin, Pfalts and Bauer, Waterbury, CT), they produced no effects on the ocular blood flow. When OH groups are four (rutin, Aldrich, Milwaukee, WI), it produced mixed effects on ocular blood flow. The attachment of rutinose and/or methoxy group in the structure did not affect the ocular blood flow one way or the other. CONCLUSION: The ocular blood flow is increased significantly by the number of OH group in the molecule, with three the best to increase the ocular blood flow.  相似文献   
62.
Background: The authors determined whether desflurane altered myocardial excitation-contraction coupling and electrophysiologic behavior in the same manner as isoflurane and sevoflurane.

Methods: The effects of desflurane on isometric force in guinea pig ventricular papillary muscles were studied in modified standard and in 26 mm K+ Tyrode solution with 0.1 [mu]m isoproterenol. Desflurane effects on sarcoplasmic reticulum Ca2+ release were also determined by examining its actions on rat papillary muscles, guinea pig papillary muscles in low-Na+ Tyrode solution, and rapid cooling contractures. Normal and slow action potentials were recorded using a conventional microelectrode technique. Ca2+ and K+ currents of guinea pig ventricular myocytes were examined.

Results: Desflurane (5.3% and 11.6%) decreased peak force to approximately 70% and 40% of the baseline, respectively, similar to the effects of equianesthetic isoflurane concentrations. With isoproterenol in 26 mm K+ Tyrode solution, desflurane markedly depressed late peaking force and modestly depressed early peak force. The rested state contractions of rat myocardium or guinea pig myocardium in low-Na+ Tyrode solution were modestly depressed, whereas rapid cooling contractures were virtually abolished after desflurane administration. Desflurane significantly prolonged the action potential duration. Desflurane reduced L-type Ca2+ current and the delayed outward K+ current but did not alter the inward rectifier K+ current.  相似文献   

63.
The immunologic risk associated with donor-specific antibodies (DSA) against Class II human leukocyte antigens (HLA) in kidney transplant (KTx) recipients is unclear. The aim of this study was to determine the outcome of KTx when DSA was detected only against HLA Class II. To isolate the impact of anti-Class II DSA, we retrospectively analyzed 12 KTx recipients who at baseline had a positive B-cell flow cytometric crossmatch (FXM) and a negative T-cell FXM. Using alloantibody specification analysis, 58.3% (7/12) had DSA against donor Class II and 41.7% had no demonstrable DSA. Biopsy-proven AMR occurred in 57% (4/7) in the Class II(+) group and 0% in the Class II(-) group (p > 0.05). Peritubular capillaries stained positive for C4d in 86% (6/7) of the Class II(+) patients and in 40% (2/5) of the Class II(-) patients (p > 0.05). One patient in the Class II(+) group lost their graft at 3 months to accelerated transplant glomerulopathy, while all other grafts were functioning 3-37 months posttransplant despite the persistence of anti-Class II DSA. We conclude that KTx recipients with clearly defined anti-Class II DSA are at risk for humoral rejection suggesting that desensitization and/or close posttransplant monitoring may be needed to prevent AMR.  相似文献   
64.
The objective of this study is to compare the effects of three different anesthetic combinations on the electroretinogram in the same animals under similar laboratory conditions. Thiopental–isoflurane (TI), medetomidine–ketamine (MK), and xylazine–ketamine (XK) were used on each of 12 healthy miniature schnauzer dogs (MS) with a period of at least 3 weeks in between subsequent anesthesia protocols, using the Dog Standard Protocol. The scotopic ERGs consisted of scotopic low stimulus strength (S) responses designated S1, S2, S3, S4, and S5, at 1, 5, 10, 15, and 20 min after dark adaptation, respectively, and scotopic standard stimulus strength (S-ST) responses. The photopic ERGs consisted of a photopic single flash (P) response and 31 Hz flicker (P-FL) responses. For S-ST (2.5 cd s/m2), the amplitude of the a-wave using TI was significantly lower than that using MK (adjusted P = 0.05) and XK (adjusted P = 0.03), and the implicit time of the a-wave was significantly shorter than that using MK (adjusted P = 0.04). For P (2.5 cd s/m2), the amplitude of the b-wave using XK was significantly higher than that using MK (adjusted P = 0.01). The implicit times of the b-wave using TI was significantly longer and shorter than that of MK for S1, S2 and P-FL and for S4 and S-ST, respectively, and than that of XK for S2 and P-FL and for S5 and S-ST, respectively. The results of the present study showed that TI affected both the amplitude and the implicit time of the a-wave for S-ST and the implicit time of the b-wave relatively more so than was the case when using XK or MK. Therefore, it appears that either XK or MK could be advantageous to use rather than TI for clinical studies.  相似文献   
65.
OBJECTIVE: Pamidronate has been studied as a therapeutic drug for various osteopenic diseases. However, avascular osteonecrosis in the jawbone has been recently reported in patients receiving pamidronate. The objective of this study was to examine the effect of pamidronate on bone regeneration in a controlled animal model. MATERIALS AND METHODS: To determine the effect of parmidronate on bone healing in a local bony defect area, a rabbit calvarial bony defect model was used and poly L-lactide-co-glycolide (PLGA) used as a drug carrier material. Four defect groups were made in each rabbit calvaria and the defects were treated as follows: untreated bony defect (group 1), PLGA only (group 2), 2 mg of pamidronate with PLGA (group 3), and 3 mg of pamidronate with PLGA (group 4). Bone healing was evaluated by radiography and histology at 1, 2, 4, 6, and 8 weeks after surgery. RESULTS: In radiographic analysis, radiopacity was lower in pamidronate groups than non-operated rabbit calvarial bone at all observation points (P < .05). In histological analysis, the initial bone formation at 1 week was not different among groups, but it was much lower in the pamidronate groups than in the control or PLGA group after 2 weeks. Newly formed bone at 1 week underwent avascular necrosis after 2 weeks in both pamidronate groups. Avascular necrosis was not observed until 8 weeks in both topically applied pamidronate groups. CONCLUSION: Collectively, pamidronate inhibits bone healing in rabbit calvarial bony defect and it may explain the avascular necrosis of the jaws in patients receiving pamidronate.  相似文献   
66.
The purpose of this study was to determine the genetic characteristics of foot polydactyly and identify its inheritance pattern by analyzing familial pedigree. Five cases from 2 Korean families were studied: 1 is a family whose members have been affected for 4 generations and the other for 2 generations. Using peripheral blood samples, we performed chromosomal analysis using the banding technique with Giemsa stain and karyotyping. We investigated the shape and structure of 46 chromosomes, looking for translation, deletion, inversion, ring chromosome, and isochromosome abnormalities. All peripheral blood samples demonstrated no chromosomal abnormalities, though the genetic nature of foot polydactyly and a new genetic locus was identified recently by other studies. Familial pedigree analysis suggested that polydactyly was inherited as an autosomal dominant trait in the first family. The mode of inheritance for the second family could not be determined due to an insufficient number of family members. The result of this study brought us to the conclusion that, while genetic factors play a major role in polydactyly, other factors may contribute to its occurrence.  相似文献   
67.
BACKGROUND: Masseteric muscle hypertrophy is an uncommon dition represented as a swelling of the masseter muscle. Recent reports have demonstrated the successful use of botulinum in the treatment of masseteric hypertrophy. OBJECTIVE: This study was a prospective trial to evaluate the effectiveness of botulinum toxin type A (Botox) in the treatment of masseteric muscle hypertrophy according to doses of 10, 20, and 30 U. MATERIALS AND METHODS: Twenty-two patients were referred to the dermatologic clinic for the management of masseteric muscle hypertrophy. Ultrasonographic measurements of the thickness of the masseter muscle were performed, and clinical photographs were taken before treatment and 1, 2, 3, 4, 6, and 9 months after the treatment. RESULTS. The median values of percentage reduction of muscle mass were 10.3%, 16.5%, 23.7%, 24.7%, 21.6%, 16.5% in the 10 U group; 11.9%, 18.8%, 24.8%, 27.7%, 26.7%, and 21.8% in the 20 U group; and 12.0%, 19.4%, 25.0%, 27.8%, 37.8%, and 24.1% in the 30 U group. CONCLUSION. The adequate dose of botulinum toxin type A for treatment of masseteric muscle hypertrophy should be above 20 U. The effect of botulinum toxin type A is maintained for at least 9 months as the treatment of masseteric muscle hypertrophy.  相似文献   
68.
E J Roth  T Park  T Pang  G M Yarkony  M Y Lee 《Paraplegia》1991,29(9):582-589
Brown-Sequard syndrome (BSS) and Brown-Sequard-plus syndrome (BSPS) are characterised by asymmetrical paresis with hypalgesia more marked on the less paretic side. This study examined the clinical features of 38 patients (30 males and 8 females; mean age = 32 years) with traumatic cervical BSS or BSPS who underwent comprehensive inpatient rehabilitation. Twenty two injuries were caused by road traffic accidents, 8 by penetrating injuries, 5 by diving injuries, and 3 by other causes. After an average of 35 days in acute care and 79 days in rehabilitation, 37 patients had increased muscle strength, all 38 patients improved functional abilities, 29 patients walked independently, 34 had spontaneous bladder emptying, 36 were discharged home, and 14 were employed. Statistically significant increases (p less than 0.001) were made in modified Barthel index functional scores between admission and discharge. Patients with BSPS had a better prognosis than did those with 'pure' BSS. Patients with predominant upper limb weakness had more favourable outcomes than did those with predominant lower limb weakness. Few other potentially predictive demographic, injury, or neurological factors were associated with functional outcome. Patients with BSS or BSPS generally have a good prognosis for neurological and functional improvement.  相似文献   
69.
The intraocular pressure and the anteroposterior length of the eye are of great clinical importance for the diagnosis and management, before and after surgery, of congenital glaucoma. It is well-known that normal intraocular pressure in children is different from the normal levels in adults. We performed measurements of intraocular pressure and axial length in 141 children who had been admitted for eye problems other than glaucoma. The intraocular pressures were measured with the Perkins hand-held applanation tonometer at the beginning of general anesthesia. Simultaneously, A-scan ultra-sound measurements of the axial lengths of the eyes were made. In 10 children under the age of two years, the intraocular pressure was 11.85 +/- 1.35 mmHg. In 79 children from two to seven years, the intraocular pressure was 12.80 +/- 1.73 mmHg. In 52 children from seven to 15 years, the intraocular pressure was 13.31 +/- 1.79 mmHg. The axial lengths of the eyes in children under the age of two years, from two to seven years, and from seven to 15 years, were 21.31 +/- 0.97 mm, 22.04 +/- 0.92 mm, and 23.22 +/- 1.00 mm, respectively. These results were considered to be guidelines for measuring intraocular pressure and axial length in children suspected of having congenital glaucoma. The differences of intraocular pressures stated by other authors are due to early measurement of the intraocular pressure at the beginning of general anesthesia.  相似文献   
70.
Several electrophoretic forms of human platelet arylsulfatase A (ASA), including variant type IIIa and normal type IVa, have been identified by nondenaturing polyacrylamide gel electrophoresis. An alcoholic population that we have analyzed is enriched in variant type IIIa compared with nonalcoholic psychiatric and normal controls. Individuals with the IIIa enzyme possess greatly reduced levels of ASA activity. To understand further the structural basis for the differences and their potential biological consequences, the nature of the ASA variant expressed by fibroblasts from different individuals was explored. The electrophoretic patterns of fibroblast ASA from the IIIa and IVa individuals differ in degree of phosphorylation. Furthermore, fibroblast ASA from IIIa individuals lacks an N -linked glycan found in ASA from IVa individuals. In addition, differences in peptide and/or posttranslational modification unrelated to the N -linked carbohydrate or phosphorylation exist between the fibroblast ASA from IIIa and IVa individuals. The finding that both fibroblasts and platelets exhibit related electrophoretic isoform patterns characteristic of the donor's ASA type allows for the use of fibroblasts to study the impact of ethanol on the metabolism of cells possessing different ASA types.  相似文献   
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