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71.
72.
OBJECTIVE: To propose a definition for stage IA1 cervical adenocarcinoma, based on the International Federation of Gynecology and Obstetrics (FIGO) staging system, and to determine if patients meeting criteria might be candidates for conservative surgery. METHODS: Two hundred women were diagnosed with early-stage cervical adenocarcinoma from 1982 to 1996. Histopathologic sections were reviewed by a gynecologic pathologist. Medical records were reviewed, and patients included in this study had microscopically identifiable lesions, up to 3 mm invasive depth, up to 7 mm tumor width, and negative margins if cone biopsy was performed. RESULTS: Twenty-one patients with microinvasive adenocarcinoma met criteria for FIGO stage IA1 carcinoma of the cervix. The median (range) follow-up was 76 (30-172) months and median (range) patient age was 38 (24-75) years. Definitive treatment included type II or III radical hysterectomy in 16 cases, simple abdominal or vaginal hysterectomy in four cases, and loop electrosurgical excision procedure in one case; one patient received adjuvant pelvic radiation. The histologic subtypes were endocervical adenocarcinoma in 18 cases, adenosquamous carcinoma in two cases, and clear-cell adenocarcinoma in one case. There was no evidence of parametrial invasion or lymph node metastases in any patient who had radical surgery, and there were no disease recurrences. CONCLUSION: Patients with microinvasive adenocarcinoma who met criteria for FIGO stage IA1 cervical carcinoma had disease limited to the cervix, and conservative surgery, such as cone biopsy or simple hysterectomy, might offer them definitive treatment. 相似文献
73.
Effects of insertions and deletions in a beta-bulge region of Escherichia coli dihydrofolate reductase 总被引:1,自引:0,他引:1
The role of a beta-bulge in Escherichia coli dihydrofolate reductase (DHFR)
has been explored by a series of insertion and deletion mutations.
Insertion of a seven amino acid sequence from a structurally equivalent
'beta-blowout' sequence from human DHFR destabilizes E. coli DHFR by 3.6
kcal/mol and decreases catalytic efficiency (kcat/K(m)) 34- fold. Deletion
of F137, delta 137, the looped out residue in the bulge, also destabilizes
E. coli DHFR by 2.8 kcal/mol but only decreases catalytic efficiency
threefold. Concurrent deletion of F137 and mutation of, V136 to proline to
try and maintain the strand twist associated with the beta-bulge decreases
protein stability by 3.4 kcal/mol and decreases catalytic efficiency
84-fold. These insertion/deletion mutations were also constructed in a D27S
DHFR background. The D27S mutation has been described previously and
proposed to remove the catalytic acid from the active site. The delta 137
mutation partially suppresses the effect of the D27S mutation as it
decreases the K(m) for substrate, dihydrofolate, twofold. Non-additive
effects are observed for the insertion/deletion mutations in wild-type
versus D27S DHFR backgrounds, consistent with structural changes.
相似文献
74.
SA Gould EE Moore FA Moore JB Haenel JM Burch H Sehgal L Sehgal R DeWoskin GS Moss 《Canadian Metallurgical Quarterly》1997,43(2):325-31; discussion 331-2
We have previously documented the safety of 1 unit (50 gram) of human polymerized hemoglobin (Poly SFH-P) in healthy volunteers. This report describes the first patient trial to assess the therapeutic benefit of Poly SFH-P in acute blood loss. Thirty-nine patients received 1 (n = 14), 2 (n = 2), 3 (n = 15), or 6 (n = 8) units of Poly SFH-P instead of red cells as part of their blood replacement after trauma and urgent surgery. There were no safety issues related to the infusion of Poly SFH-P. The plasma hemoglobin concentration ([Hb]) after the infusion of 6 units (300 gram) of Poly SFH-P was 4.8 +/- 0.8 g/dL (mean +/- SD). Although the red cell [Hb] fell to 2.9 +/- 1.2 g/dL, the total [Hb] was maintained at 7.5 +/- 1.2 g/dL. Poly SFH-P maintained total [Hb], despite the marked fall in red cell [Hb] due to blood loss. The utilization of O2 (extraction ratio) was 27 +/- 16% from the red cells and 37 +/- 13% from the Poly SFH-P. Twenty-three patients (59%) avoided allogeneic transfusions during the first 24 hours after blood loss. Poly SFH-P effectively loads and unloads O2 and maintains total hemoglobin in lieu of red cells after acute blood loss, thereby reducing allogeneic transfusions. Poly SFH-P seems to be a clinically useful blood substitute. 相似文献
75.
J García-Samaniego V Soriano J Castilla R Bravo A Moreno J Carbó A I?iguez J González F Mu?oz 《Canadian Metallurgical Quarterly》1997,92(7):1130-1134
OBJECTIVES: The factors influencing the histological severity of chronic hepatitis C (CHC) have not been well established. We therefore investigated the effect of hepatitis C virus (HCV) genotypes and human immunodeficiency virus (HIV) infection on histological liver damage in a cohort of intravenous drug users with CHC. METHODS: We analyzed the histological activity score and the HCV genotypes in 59 HCV-RNA-positive patients with biopsy-proven CHC. Forty-eight (81%) of them had concomitant HIV infection with a CD4+ cell count above 200 x 10(6) cells/L and an absence of AIDS-defining conditions. Multivariate analysis was performed to determine the features associated with the histological severity. RESULTS: Minimal/mild hepatitis was found in 16 patients (27%), moderate chronic hepatitis in 29 (49%), and severe chronic hepatitis in 14 (24%). Patients with HCV subtype 1b had a higher histological score than others (8.7 +/- 3.3 vs. 6.5 +/- 3.2, p = 0.012), either as single or mixed infections. In multivariate analysis, HIV-infected individuals had a higher score of piecemeal necrosis (OR = 21.7, p = 0.002) and a higher stage of fibrosis (OR = 17.9, p = 0.004) than patients without HIV infection. HIV infection and HCV genotype 1b were found to be independent factors of histological severity. CONCLUSIONS: Liver damage in patients with CHC seems to be directly influenced by HCV subtypes. Infection by HCV subtype 1b is closely associated with more severe forms of liver pathology. Furthermore, the presence of HIV infection is an independent factor associated with more aggressive histological damage. In these patients, higher degrees of piecemeal necrosis and fibrosis are commonly seen. 相似文献
76.
77.
DA Partrick DD Bensard EE Moore MD Partington FM Karrer 《Canadian Metallurgical Quarterly》1998,33(11):1712-1715
BACKGROUND/PURPOSE: The aim of this study was to investigate driveway-related injuries in children, identify associated risk factors, and evaluate outcome compared with other mechanisms of blunt trauma. METHODS: A 6-year review (1991 to 1996) of pediatric (age less than 18 years) pedestrian injuries treated at two urban trauma centers was conducted: one regional pediatric trauma center and one level I trauma center with pediatric commitment. Five hundred twenty-seven children injured in pedestrian accidents were identified from the trauma registry; 51 children (10%) sustained traumatic injuries as a result of being struck in their driveway. Data are reported as mean +/- SEM. RESULTS: Children less than 5 years of age (n = 41) had an injury severity score (ISS) of 12.3+/-2.3, 15 (37%) sustained closed head injury, 13 (37%) had torso trauma, 19 (46%) skeletal trauma, and eight (20%) died. Children > or = 5 years old (n = 10) had an ISS of 10.7+/-2.4, three (30%) sustained closed head injury, four (40%) torso trauma, six (60%) skeletal trauma, and none died. In contrast, all other pediatric pedestrian accidents analyzed over the same time period had a mortality rate of only 2% (11 of 476). CONCLUSIONS: Pediatric driveway trauma carries a significant risk of head injury and a 10-fold increase in mortality in children under 5 years of age when compared with all other pediatric pedestrian accidents. More emphasis must be placed on injury prevention and public education to prevent this devastating mechanism of injury in these young, vulnerable children. 相似文献
78.
79.
EE Miniat EB Khomiakova MV Petrova MZ Gorgoshidze VI Ivanov 《Canadian Metallurgical Quarterly》1998,32(6):1013-1019
A HPLC method was developed and validated for the quantitation of 9-cis-retinoic acid (ALRT1057) and its major metabolite, 4-oxo-9-cis-retinoic acid (LG100182) in human plasma. Samples were buffered and extracted with methyl-tert-butyl-ether. The analytes and an I.S. were separated on a C18 HPLC column using a shallow gradient of 70-89% organic solvent. The analytes were quantitated by UV detection at 348 nm. Selectivity against endogenous compounds and potential metabolites (retinol, all trans-, 13-cis-, and 4-hydroxy-9-cis-retinoic acid) was demonstrated. The run time was 29 min. The standard curve was linear from 2.5 to 450 ng ml-1. Interassay precision for both analytes in quality control samples was less than 5.0% RSD. Accuracy was within 11.0% RE for both compounds. Analyte stability during sample storage, extraction processing, and chromatography was established. Method ruggedness was tested by two analysts and on two HPLC systems. This method has been applied to the quantitation of clinical samples. 相似文献
80.
EE Brooks NS Gray A Joly SS Kerwar R Lum RL Mackman TC Norman J Rosete M Rowe SR Schow PG Schultz X Wang MM Wick D Shiffman 《Canadian Metallurgical Quarterly》1997,272(46):29207-29211
The activity of cyclin-dependent kinase 2 (CDK2) is essential for progression of cells from G1 to the S phase of the mammalian cell cycle. CVT-313 is a potent CDK2 inhibitor, which was identified from a purine analog library with an IC50 of 0.5 microM in vitro. Inhibition was competitive with respect to ATP (Ki = 95 nM), and selective CVT-313 had no effect on other, nonrelated ATP-dependent serine/threonine kinases. When added to CDK1 or CDK4, a 8.5- and 430-fold higher concentration of CVT-313 was required for half-maximal inhibition of the enzyme activity. In cells exposed to CVT-313, hyperphosphorylation of the retinoblastoma gene product was inhibited, and progression through the cell cycle was arrested at the G1/S boundary. The growth of mouse, rat, and human cells in culture was also inhibited by CVT-313 with the IC50 for growth arrest ranging from 1.25 to 20 microM. To evaluate the effects of CVT-313 in vivo, we tested this agent in a rat carotid artery model of restenosis. A brief intraluminal exposure of CVT-313 to a denuded rat carotid artery resulted in more than 80% inhibition of neointima formation. These observations suggest that CVT-313 is a promising candidate for evaluation in other disease models related to aberrant cell proliferation. 相似文献