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101.
In this paper we will review the results obtained during the last 2 years with the aponeurotic galea and subgalea for vermillion lip augmentation. The survey was carried out on 42 patients who displayed either an absence of or reduction in the vermillion of one or both lips or a senile lip. In all cases the surgical procedure introduced aponeurotic galea and subgalea in the space found between the orbicular lip muscle and the vestibular mucus, just behind the vermillion. All the operations were performed under local anaesthetic. The size of the aponeurotic galea fragment removed varied in length between 10 and 12 cms. and in width between 1 and 2 cms., using the following parameters for its dimensions: the previous volume of the lips, and the distance between the two buccal commissures when in the “smile position.”  相似文献   
102.
 Styrene is stereoselectively oxidized by cytochrome P450 to its reactive metabolite, styrene oxide. The (R)- and (S)-enantiomers of styrene oxide can be conjugated with glutathione (GSH) to both (R)- and (S)-diastereoisomers of the specific mercapturic acids, N-acetyl-S-(1-phenyl-2-hydroxyethyl)-L-cysteine (M1) and N-acetyl-S-(2-phenyl-2-hydroxyethyl)-L-cysteine (M2). Several investigations have indicated different toxic potential of the (R)- and (S)-configurations of styrene oxide and its GSH- and N-acetyl-conjugates. In this study the mercapturic acid diastereoisomers were measured in the urine of rats exposed to styrene in combination with ethanol, a good inducer of styrene metabolism. Male Sprague-Dawley rats were given an isocaloric liquid diet containing ethanol (5% w/v) for 3 weeks. Starting from the 2nd week, the animals were also exposed to styrene vapours (300 ppm, 6 h/day, 5 days/week) in a dynamic exposure chamber. Both the (R)- and (S)-diastereoisomers of the M1 and M2 as well as the conventional biomarkers, mandelic acid (MA) and phenylglyoxylic acid (PGA) were measured in urinary samples. Approximately 30 and 25% reduction of the levels of brain non-protein sulfhydryls (NPS) was observed in the animals given styrene and ethanol, respectively, while the combined ethanol and styrene treatment resulted in a 60% decrease. Ethanol consumption also resulted in higher urinary levels of the M1-R, M1-S and M2 metabolites associated with increased M1-R/S ratio and higher urinary MA excretion compared to animals treated with styrene. These results suggest that the urinary mercapturic acid diastereoisomers may be used as a noninvasive tool to examine stereoselective patterns of styrene metabolism in vivo, as well as their alterations caused by ethanol. These compound-specific mercapturic acids may also be valuable indicators of styrene-induced disorders of GSH homeostasis in nonaccessible organs. Received: 19 December 1995/Accepted: 10 May 1996  相似文献   
103.
Objective: To retrospectively review the management of adenocarcinomain situof the uterine cervix, to determine the outcome of conization versus hysterectomy, and to compare the results achieved by different methods of conization. Methods: We performed a retrospective pathology and chart review of 46 patients with cervical adenocarcinomain situfrom January 1980 to October 1994. Results: Nine patients were managed during the first half of the study period and 37 were managed in the second half. The mean age of patients was 38.4 years (range 25–72). Forty-five of 46 patients were diagnosed as a result of an abnormal Pap smear, although only 19 smears indicated adenocarcinomain situor other glandular abnormalities. Cold knife conization resulted in a 33% rate of positive margins for adenocarcinomain situcompared to 50% for large loop excision of the transformation zone (LLETZ). Among 24 conservatively managed patients with negative conization margins, there have been 2 (8.3%) recurrences of adenocarcinomain situ.Among patients not undergoing hysterectomy as definitive treatment, 1 of 18 (6%) patients undergoing cold knife conization recurred, compared to 4 of 14 (29%) managed with LLETZ, despite a 63.4-month shorter mean follow-up interval for the LLETZ patients. Conclusions: Cold knife conization is associated with a lower rate of recurrence of cervical adenocarcinomain situcompared to LLETZ. We recommend cold knife conization for patients who are not treated with hysterectomy.  相似文献   
104.
Enzymatic synthesis of penicillins   总被引:5,自引:0,他引:5  
Different penicillins (phenylacetyl, 2-hydroxyphenylacetyl, 4-hydroxyphenylacetyl, phenoxyacetyl and 2-thiopheneacetylpenicillin) have been synthesized "in vitro" by direct N-acylation of 6-aminopenicillanic acid (6-APA) with the acyl group of several acyl-CoA derivatives. The enzyme that catalyzes these reactions, acyl-CoA: 6-APA acyltransferase of Penicillium chrysogenum, was purified to homogeneity (374-fold) and its amino acid composition is given. This protein accepts as substrates several aliphatic acids and different aromatic acids with the only requirement that an acetyl-CoA moiety must be present in the substrate molecule. Shortening or lengthening of the acyl moiety prevents the 6-APA-N-acylation reaction. The presence of an amino group in the alpha-position of the acetyl group does not allow this molecule to be used as substrate. However, different substitutions in the phenyl group (hydroxylation of the carbons 2 and 4) or its replacement by another aromatic ring (thiophene) were accepted with varying reactions rates in the acylation reaction when a 176-fold purified acyltransferase was employed. The homogeneity pure enzyme accepts as substrate thiophene acetyl-CoA but it did not 2-hydroxyphenyl and 4-hydroxyphenylacetyl-CoA. The presence of an oxygen atom between the aromatic and the acetyl moieties did not affect the catalysis.  相似文献   
105.
A high-performance liquid chromatographic (HPLC) method is described for the assay of the active metabolite [1-(2-pyrimidinyl)piperazinel of buspirone, an anxiolytic agent, in rat plasma.

The method is based on the use of ion-pair HPLC coupled to a liquid—solid extraction scheme. Samples of rat plasma (2 ml) with internal standard (1-phenylpiperazine), adjusted to pH 10.5 with borate buffer, were loaded on to a preactivated C-18 cartridge. The metabolite and the internal standard were eluted with 5 ml of methanol and injected on to a reversed-phase 10-μm Spherisorb ODS-2 column. The column was eluted with a mobile phase of 0.005 M sodium lauryl sulphate in citrate buffer (pH 3.6)-acetonitrile (65:35, v/v) at 2 ml min−1. Detection was carried out at 248 nm. The recovery of the metabolite was 55%. The method was applied to the determination of the metabolite in rat plasma after oral dosing (25 mg kg−1) of the parent compound.  相似文献   

106.
The authors describe the different "retentive complexes" proposed by the Akers, Roach and Ney schools and analyse their biomechanical validity.  相似文献   
107.
DNA isolated from chondrosarcoma cells effectively transformedNIH-3T3 cells and human foreskin fibroblasts. The transfectedNIH-3T3 cells, directly implanted three or four passages later,formed progressively growing tumors ( 2.0 cm in diameter) subcutaneouslyin nude mice. No metastasis was evident upon pathological examinationof the tumor bearing mice. Transfected human foreskin fibroblaststhat exhibited anchorage independent growth formed only smalltumors in nude mice (<0.6 cm in diameter). The transfectedhuman cells which exhibited anchorage independent growth reactedwith the monoclonal antibody 345.134S, specific for an epitopeexpressed by human sarcoma cells. The transfected NIH-3T3 cellsdid not exhibit reactivity with the same monoclonal antibody.Southern blot analysis of the DNA prepared from the transfectedNIH-3T3 cells, that developed as a progressively growing tumorin a nude mouse, revealed the presence of human repetitive DNAsequences.  相似文献   
108.
Wild rodents and the subadult Ixodes ricinus (L.) ticks infesting them were examined for the presence of Borrelia burgdorferi Johnson, Schmid, Hyde, Steigerwalt & Brenner s.l. in a sylvatic habitat in west central Poland during May-September 2002. In total, 818 feeding ticks were recovered from 73 infested yellow-necked mice, Apodemus flavicollis Melchior; in addition, bank voles, Clethrionomys glareolus Schreber, were rarely captured and proved to be weakly parasitized. Only 2.7% of A. flavicollis and 2.2% of 320 engorging larvae were polymerase chain reaction (PCR) positive for the bacterium. All spirochete-PCR-positive samples yielded exclusively B. burgdorferi s.s. This genospecies was also the most prevalent in questing nymphs and accounted for 87.5% of the total number of Borrelia infections in nymphal ticks collected during May and June 2 yr later. The presence of the same genospecies both in naturally engorged larvae and blood-positive animals as well as the high predominance of B. burgdorferi s.s. in questing nymphs strongly differs from most study sites investigated in Europe. This unique pattern of Borrelia-diversity in both rodents and ticks seems to be determined by highly site-specific host vertebrate cenosis, and yellow-necked mice are involved in the maintenance of B. burgdorferi s.s. in the forest habitat. However, the transmission efficiency of this spirochete from the mice to the I. ricinus vector seems to be very low. The research provides additional information on the complexity of B. burgdorferi s.l. ecology in Europe, pointing to the importance of the local host community.  相似文献   
109.
Williams or Williams-Beuren syndrome (WBS) is a developmental disorder with multisystemic manifestations characterized by distinctive facial features, mental disability with unique cognitive and personality profiles, vascular stenoses, growth retardation, and occasional infantile hypercalcemia, caused by haploinsufficiency for genes deleted in chromosome band 7q11.23. However, with the exception of arterial stenoses caused by haploinsufficiency for the elastin gene (ELN), no specific implication of any other gene in the phenotype has been established. We present two patients with portal hypertension leading to splenomegaly and pancytopenia carrying the common 1.5 Mb WBS deletion. We propose this is an additional severe vascular complication of ELN deficiency and discuss the specific characteristics of the portal venous tract that could explain the impact of ELN deficiency in that venous territory. This complication is potentially lethal and should thus be considered in any patient with WBS and splenomegaly.  相似文献   
110.
The cytokines that predominate at the healthy maternal fetal interface are compatible with those produced by Th2/3 cells. Th1 and Th2 type immunity are mutually inhibitory and cytokine profiles are regulated in part by maternal sex steroids. The immune and endocrine equilibrium required for pregnancy success may be modified by external factors including stress, infection and altered maternal nutrition. The latter has received surprisingly little attention particularly as the effects of nutrition on immunity per se are widely documented. We have used animal models to investigate the effects of altered maternal diet on both immune and endocrine mechanisms important for pregnancy success. In rodents, maternal deficiencies in iron and vitamin A have been shown to negatively alter the expression of placental cytokines and in the case of vitamin A, increase placental apoptosis. In a highly controlled sheep model, overfeeding young growing females carrying singleton pregnancies restricts placental growth resulting in the premature delivery of low birth weight lambs. This is associated with reduced maternal concentrations of progesterone, placental lactogen, PSPB, GH and increased insulin, IGF-1, leptin and thyroid hormones (Wallace et al. Reprod 2001; 122:347–357). At day 80 of gestation (term=145) the placentae of overfed dams exhibit reduced expression of proliferation markers, predominantly in the fetal trophectoderm, and increased expression of the pro-apoptotic protein bax. These data indicate an altered balance between placental proliferation and apoptosis, possibly linked to maternal endocrine status. We conclude that maternal diet has considerable impact on immuno-endocrine mechanisms critical for pregnancy success.  相似文献   
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