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51.
52.
Injury to the growth plate after Pemberton osteotomy 总被引:3,自引:0,他引:3
Leet AI Mackenzie WG Szoke G Harcke HT 《The Journal of bone and joint surgery. American volume》1999,81(2):169-176
The Pemberton osteotomy involves cutting directly into the iliopubic and ilioischial limbs of the triradiate cartilage of the acetabulum. Complete closure of the triradiate cartilage after this osteotomy has been described in case reports. The present experimental study was performed to determine whether physeal osseous bars formed after Pemberton osteotomy. Eight Pemberton osteotomies were performed in six piglets. The animals were killed, and the acetabula were studied with use of radiography, computed tomography, and histological analysis for evidence of physeal injury. Plain anteroposterior radiographs of the pelvis did not clearly demonstrate the formation of osseous bars. However, Bucholz radiographs, made with the acetabulum placed directly on the cassette, showed osseous bars in three of the four specimens that were studied in this manner. Histological sections of the eight specimens of triradiate cartilage demonstrated five osseous bars in the iliopubic limb and four in the ilioischial limb. In two specimens, there was disruption of the cartilage without osseous bridging. Only two of the eight specimens had normal histological findings in both the iliopubic and the ilioischial limb of the triradiate cartilage. 相似文献
53.
54.
RAL Dampney Y. Hirooka PD Potts GA Head 《Clinical and experimental pharmacology & physiology》1996,23(Z3):105-111
- 1 It was first shown several years ago that the rostral part of the ventrolateral medulla (VLM) contains a high density of receptor binding sites for angiotensin II (AngII). In the present paper we briefly review recent studies aimed at determining the actions of both exogenous and endogenous angiotensin peptides in the rostral VLM, as well as their specific sites of action.
- 2 The results of these studies have shown that angiotensin peptides can excite pressor and sympathoexcitatory neurons in the rostral VLM, but do not appear to affect non-cardiovascular neurons in this region.
- 3 It is known that pressor neurons in the rostral VLM include both catecholamine and non-catecholamine neurons. There is evidence that, at least in conscious rabbits, both of these types of neurons are activated by AngII. The specific endogenous angiotensin peptide or peptides that affect pressor neurons in the rostral VLM have not yet been definitively identified.
- 4 It is also possible that different angiotensin peptides may have different effects on pressor neurons in the rostral VLM, mediated by different receptors. Further studies will be needed to define these different functions as well as the specific receptors and cellular mechanisms that subserve them.
55.
Process and outcome measures were compared in two long-term groups. The measure "Relatedness" reflected an individual's attachment to and comfort with the group, and "Group Work" indicated perception of the group as having a positive working climate. High Relatedness scores predicted better outcome at 18-month follow-up. Group Work scores were not related to outcome. Relatedness and Group Work scores were not correlated. Results replicate in a group psychotherapy population the importance, reported in individual therapy literature, of an early and sustained positive therapeutic alliance (Relatedness). However, a measure that is closely related to the concept of "working alliance" (Group Work) did not predict outcome. 相似文献
56.
J. C. Cailliez D. Poulain D. W. R. Mackenzie L. Polonelli 《European journal of epidemiology》1992,8(3):452-459
Expression of antigenic epitopes shared by secreted yeast glycoproteins was studied using specific immunological probes. Application of cytological and ultrastructural methods of immunodetection, employing monoclonal antibodies, permitted us to localize these glycoproteins in the cytoplasm, through the cell wall and at the yeast cell surface. Importance of glycosylation-secretion relationships were evaluated in the secretion process of these molecules. The cell wall crossing and the cell surface distribution of antigenic glycoproteins was described in immunoelectron microscopy and immunofluorescence. Some preferential secretion ways were suspected through the yeast cell wall leading to an heterogenous distribution of cell surface glycoproteins destined to be excreted into the medium.Antigenic variability of cell wall glycoproteins expression was discussed in relation with the glycloprotein secretion. 相似文献
57.
Summary Full-length dsDNA clones that encode the genomes of two Australian turnip yellow mosaic isolates, TYMV-BL and TYMV-CL have been constructed. These clones were transcribed to give 6.3 kb capped ssRNA which infects Chinese cabbages to give symptoms indistinguishable from those produced by the parental viruses. Extensions of up to 26 nucleotides at the 3 end of the TYMV-BL clone delay infections, but virus particles isolated from these plants 4 weeks after inoculation contain RNA with the original TYMV-BL 3 terminus. A 90 nucleotide-long portion of the virion protein gene of TYMV-BL was replaced by a synthetic 90-mer primer with 16 nucleotide changes to decrease the large cytosine content (34–42%) characteristic of tymovirus genomic RNA. No reversion of any of the mutated nucleotides to cytosine occurred during 7 passages in Chinese cabbage. Hybrids between the TYMV-BL and TYMV-CL clones were also constructed, by exchanging various portions of the genome. However, it was not possible to determine definitively which part of the viral genome is responsible for the more severe symptoms caused by TYMV-BL as the hybrids gave intermediate symptoms. 相似文献
58.
Andrew N Stone Peter I Mackenzie Aleksandra Galetin J Brian Houston John O Miners 《Drug metabolism and disposition》2003,31(9):1086-1089
Morphine elimination involves UDP-glucuronosyltransferase (UGT) catalyzed conjugation with glucuronic acid to form morphine 3- and 6-glucuronides (M3G and M6G, respectively). It has been proposed that UGT2B7 is the major enzyme involved in these reactions, but there is evidence to suggest that other isoforms also catalyze morphine glucuronidation in man. Thus, we have characterized the selectivity and kinetics of M3G and M6G formation by recombinant human UGTs. UGT 1A1, 1A3, 1A6, 1A8, 1A9, 1A10, and 2B7 all catalyzed M3G formation, but only UGT2B7 formed M6G. The kinetics of M3G formation by the UGT1A family isoforms was consistent with a single enzyme Michaelis-Menten model, with apparent Km values ranging from 2.6 to 37.4 mM. In contrast, M3G and M6G formation by UGT2B7 exhibited atypical kinetics. The atypical kinetics may be described by a model with high- and low-affinity Km values (0.42 and 8.3 mM for M3G, and 0.97 and 7.4 mM for M6G) from fitting to a biphasic Michaelis-Menten model. However, a multisite model with an interaction between two identical binding sites in a negative cooperative manner provides a more realistic approach to modeling these data. According to this model, the respective binding affinities (Ks) for M3G and M6G were 1.76 and 1.41 mM, respectively. These data suggest that M6G formation may be used as a selective probe for UGT2B7 activity, and morphine glucuronidation by UGT2B7 appears to involve the simultaneous binding of two substrate molecules, highlighting the need for careful analysis of morphine glucuronidation kinetics in vitro. 相似文献
59.
GA Smith SD Strausbaugh C Harbeck-Weber DM Cohen BJ Shields JD Powers 《Pediatrics》1997,100(5):825-830
OBJECTIVE: To compare the effectiveness of three new topical anesthetics that do not contain cocaine (prilocaine-phenylephrine, tetracaine-phenylephrine [tetraphen], and tetracaine-lidocaine-phenylephrine) to that of tetracaine-adrenaline-cocaine (TAC) during laceration repair in children. DESIGN: Prospective, randomized, double-blind clinical trial. SETTING: The emergency department of an urban children's hospital. PARTICIPANTS: Children 1 year of age or older with a laceration = 5 cm in length that required suturing. Intervention. A total of 240 children were randomly assigned to one of four treatment groups. OUTCOME MEASURES: Pain felt during suturing was scored by suture technicians, research assistants, parents, and patients >/= 5 years of age using a visual analogue scale (VAS). Suture technicians, research assistants, and parents also scored pain using a seven-point Likert scale. In addition, suture technicians completed an anesthetic effectiveness scale. RESULTS: There was consistently no difference demonstrated between the effectiveness of tetraphen and that of TAC for each outcome measure of each observer group. A statistically significant difference was seen among anesthetics when comparing VAS and Likert scale scores of suture technicians and Likert scale scores of research assistants. Based on post hoc analyses, these statistically significant differences were between TAC and prilocaine-phenylephrine (suture technician VAS and Likert scale) and between TAC and tetracaine-lidocaine-phenyl-ephrine (suture technician Likert scale), but not between TAC and tetraphen. When power analyses were performed using alpha = 0.05 and beta = 0.20, it was possible to detect a difference of 1.2 VAS units for each of the observer groups. Based on anesthetic effectiveness scale scores, the three new topical preparations collectively performed significantly better on the face and scalp than on the extremities (relative risk = 1.83; 95% confidence interval 1.20 < relative risk < 2.79). CONCLUSION: This study demonstrated the effectiveness and safety of three new non-cocaine-containing topical anesthetics. Consistently, there was no statistical difference demonstrated between the effectiveness of tetraphen and that of TAC for each outcome measure of each observer group. Tetraphen offers an effective alternative to TAC during laceration repair in children. 相似文献
60.
Mifepristone (RU-486) has recently been granted approval from the Food and Drug Administration for the early termination of pregnancy. Availability is anticipated during 1997. This article describes the pharmacologic function of mifepristone and discusses its potential clinical use in the United States, including its safety, efficacy, and possible complications. 相似文献