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941.
OBJECTIVE: The new FIGO staging for endometrial cancer cases complies with other forms of surgical staging and correlates better with clinical outcomes because it includes prognostic factors. This study was done to investigate whether total abdominal hysterectomy with bilateral salpingo-oophorectomy (TAH+BSO) is adequate for new FIGO Stage I endometrial carcinoma. SUBJECTS: Sixty-five cases of endometrial carcinoma defined according to the new FIGO Stage Ia (n = 26), Ib (n = 24) and Ic (n = 15) were analysed. They all received TAH+BSO only and were followed up for at least two years. METHODS: The histologic type, grade, depth of myometrial invasion, lympho-vascular tumour emboli and tumour size were analysed by t-test to correlate the risk factors for treatment failure. RESULTS: There were no recurrences after TAH+BSO in Ia and Ib cases. However, recurrences occurred in five cases (33%) of Stage Ic with deep myometrial invasion, high histologic grade, large tumour size and tumour emboli. CONCLUSIONS: TAH+BSO is inadequate in some Ic cases with a high histologic grade, deep myometrial invasion and tumour emboli. Thus, thorough pre-operative and intra-operative staging, adequate operation method and prompt post-operative adjuvant therapy are indispensable for successful treatment.  相似文献   
942.
Recombinant DNA fragments from Leishmania aethiopica that code for epitopes which react with human antibodies have been characterized by cross-hybridization studies and DNA sequence analysis. Twenty clones could be grouped into seven different groups (I-VII), probably representing seven different L. aethiopica antigens. The DNA sequences of representative clones from the seven groups have been obtained and the amino acid sequence of the respective recombinant antigens established. The recombinant antigens have been analysed by epitope scanning with patient sera, and octapeptides that contain potential B-cell epitopes have been identified in all seven recombinant antigens. These octapeptides have further been tested with additional patient sera and control sera, and three octapeptides (HAFCHEEG, YHSSVVHD and SYAPCSLK) were found to contain major epitopes recognizing specific antibodies in nine, seven and four, respectively, of the twenty sera tested. Fifteen of the twenty sera reacted with one or more of these three octapeptides.  相似文献   
943.
The three-dimensional structure of a secreted aspartic protease from Candida albicans complexed with a potent inhibitor reveals variations on the classical aspartic protease theme that dramatically alter the specificity of this class of enzymes. The structure presents: (1) an 8-residue insertion near the first disulfide (Cys 45-Cys 50, pepsin numbering) that results in a broad flap extending toward the active site; (2) a 7-residue deletion replacing helix hN2 (Ser 110-Tyr 114), which enlarges the S3 pocket; (3) a short polar connection between the two rigid body domains that alters their relative orientation and provides certain specificity; and (4) an ordered 11-residue addition at the carboxy terminus. The inhibitor binds in an extended conformation and presents a branched structure at the P3 position. The implications of these findings for the design of potent antifungal agents are discussed.  相似文献   
944.
BuPdGMPNHPP was synthesized and assayed as a non-incorporable inhibitor of B family DNA polymerases. The derivative was synthesized by preparation of the imidophosphorane of BuPdG followed by reaction with orthophosphate using the imidazolide method. BuPdGMPNHPP inhibited human DNA polymerase alpha and T4 DNA polymerase 10 and 3.5-times more potently than BuPdGTP, respectively, and was not a substrate for either enzyme. BuPdGMPNHPP acts as an active site affinity probe that could find use in co-crystallization trials of B family DNA polymerases.  相似文献   
945.
946.
Mature female sperm whales (Physeter macrocephalus) live in socially cohesive groups of 10-30, which include immature animals of both sexes, and within which there is communal care of the young. We examined kinship in such groups using analyses of microsatellite DNA, mitochondrial DNA sequence, and sex-linked markers on samples of sloughed skin collected noninvasively from animals in three groups off the coast of Ecuador. Social groups were defined through photographic identification of individuals. Each group contained about 26 members, mostly female (79%). Relatedness was greater within groups, as compared to between groups. Particular mitochondrial haplotypes were characteristic of groups, but all groups contained more than one haplotype. The data are generally consistent with each group being comprised of several matrillines from which males disperse at about the age of 6 years. There are indications of paternal relatedness among grouped individuals with different mitochondrial haplotypes, suggesting long-term associations between different matrilines.  相似文献   
947.
948.
Density Stratification Effects in Sand-Bed Rivers   总被引:1,自引:0,他引:1  
In this paper the effects of density stratification in sand-bed rivers are studied by the application of a model of vertical velocity and concentration profiles, coupled through the use of a turbulence closure that retains the buoyancy terms. By making the governing equations dimensionless, it is revealed that the slope is the additional dimensionless parameter introduced by inclusion of the buoyancy terms. The primary new finding is that in general density stratification effects tend to be greater in large, low-slope rivers than in their smaller, steeper brethren. Under high flow conditions the total suspended load and size distribution of suspended sediment can be significantly affected by density stratification, and should be accounted for in any general theory of suspended transport.  相似文献   
949.
950.
We are pleased to initiate, with this issue, the column “Talking About Color …”, which Professor W. David Wright has agreed to write for this journal. It is indeed a privilege to provide, on a continuing basis, thoughts about color from this distinguished colorist and educator. Our thanks go also to the incoming Editor-in-Chief, Rolf G. Kuehni, for suggesting and arranging for Dr. Wright's column. We expect it to appear in each issue.  相似文献   
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