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121.
WR Hart DE Townsend JO Aldrich BE Henderson M Roy B Benton 《Canadian Metallurgical Quarterly》1976,37(2):763-775
A total of 98 colposcopically directed biopsies were obtained from the vagina, cervix, and cervicovaginal ridge (hood) of 80 young women believed to have had intrauterine exposure to stilbestrol (DES). Specific investigation of the patient's medical records corroborated the history of maternal stilbestrol administration in 36 patients (45%), while in the remainder the drug history was regarded as presumptive since medical records were unavailable for review. The findings did not differ significantly in those biopsies taken from patients with confirmed or presumptive drug histories. Histologic evidence of vaginal adenosis was detected in vaginal biopsies from 43 patients. In 30 cases (70%) benign Müllerian-type glandular epithelium was in the superficial vaginal wall, residing on the mucosal surface and/or in the lamina propria. The glandular epithelium predominantly was of endocervical type, but in six instances it resembled endometrial or fallopian tubal epithelium. The glands were accompanied by varying degrees of squamous metaplasia in 22 cases. When extensive the metaplasia produced transformation zones similar to those seen in the normal cervix. Vaginal biopsies of adenosis from the other 13 patients (30%) revealed squamous metaplasia without demonstrable glands due to complete transformation of all antecedent glandular epithelium by squamous metaplasia. Our studies indicate that squamous metaplasia is a component of major importance in the natural history of adenosis and that the concept of adenosis should be broadened to include those examples comprised exclusively of metaplastic epithelium. In such examples metaplasia is identified by the immaturity and poor glycogenation of the squamous cells and their accompanying squamous pegs which often contain residual gland openings or squamous "eddies." Similar findings were present in biopsies of seven cervicovaginal ridges and in cervical biopsies from 37 patients, except for the absence of endometrial or tubal type glands in the latter site. Although no adenocarcinomas were detected, six patients had squamous dysplasia of the vagina and/or cervix. In no case were premalignant or dysplastic changes of glandular cells found. Our findings support the thesis that stilbestrol-associated adenosis represents anomalous embryologic localization of the original squamocolumnar junction in the vagina rather than in the cervix. It is closely related to so-called cervical "erosions." The development of squamous metaplasia accounts for modifications in the clinical and histologic appearances by producing transformation zones which then may be subject to the same oncogenic stimuli for squamous neoplasia as are their counterparts in the cervix. 相似文献
122.
123.
BE Watkins JO Davis RC Hanson TE Lohmeier RH Freeman 《Canadian Metallurgical Quarterly》1976,231(3):954-960
Unilateral renal artery plication in dogs reduced renal blood flow by 80% and produced a sustained elevation in arterial pressure whereas plasma renin activity increased for only 4 days. Sodium was retained for 3 days after plication, but this response is similar to that after a sham operation. Of seven dogs studied chronically, elevated arterial pressure was sustained for 27 days or longer in six animals. In three dogs hypertension continued for 2 mo before collateral vessels developed and arterial pressure fell; ligation of these collaterals restored hypertension. Arterial pressure was unaffected by an infusion of [1-sarcosine, 8-alanine] angiotensin II in chronic hypertensive dogs on a normal sodium intake. This angiotensin antagonist lowered arterial pressure after sodium depletion, but became ineffective following rapid sodium repletion. Chronic hypertensive dogs showed normal responses to deoxycorticosterone acetate. These findings suggest that the renin-angiotensin system is not critically involved in maintenace of chronic two-kidney renovascular hypertension in the dog. The data also show that the homeostatic role played by the renin-angiotensin system in the maintenance of arterial pressure remained intact in chronic hypertension. 相似文献
124.
125.
KM Mattila C Forsell T Pirttil? JO Rinne T Lehtim?ki M R?ytt? L Lilius A Eerola PH St George-Hyslop H Frey L Lannfelt 《Canadian Metallurgical Quarterly》1998,44(6):965-967
In early-onset familial Alzheimer's disease (AD) pathogenic mutations have been found in the amyloid precursor protein (APP) gene and in the presenilin (PS)-1 and PS-2 genes. We screened for mutations in these genes in 20 patients with familial AD from the Finnish population. In addition, we sampled 41 sporadic AD patients and 59 controls to test for mutations identified in our familial AD cases. We detected an A-to-G transition in the PS-1 gene, resulting in a glutamic acid (Glu)-to-glycine (Gly) substitution at codon 318 in 2 familial and 2 sporadic AD patients. The Glu318Gly mutation has previously been reported to cause AD. We also found the Glu318Gly mutation in 4 healthy aged controls (range, 74-87 years). We thus conclude that the mutation is most likely a rare polymorphism not related to AD. 相似文献
126.
Contrast agents in acute myocardial infarction 总被引:2,自引:0,他引:2
Hemmingsson A Bjerner T Ericsson A Johansson L Ahlström H 《Magma (New York, N.Y.)》2001,12(2-3):96-98
The experimental design in examination of acute myocardial infarctions should be valid in terms of flow, perfusion and re-flow
after intervention. The contrast agents concentration in experimental studies can be measured by microdialysis. We have assessed
the usefulness of different extracellular and blood pool contrast agents for visualization of the area at risk in coronary
artery occlusions. The double contrast technique, where Dy-DTPA-BMA was combined with Gd-DTPA-BMA yielded a superior infarct
visualization. Blood pool agents for example NC100/150 injection is also promising in first path myocardial perfusion imaging. 相似文献
127.
Constantin Sârbu Andréas Johansson Neeraj Suri Nachiappan Nagappan 《Empirical Software Engineering》2010,15(4):380-422
As the complexity of modern Operating Systems (OS) increases, testing key OS components such as device drivers (DD) becomes increasingly complex given the multitude of possible DD interactions. Currently, DD testing entails a broad spectrum of techniques, where static (requiring source code) and dynamic (requiring the executable image) and static-dynamic testing combinations are employed. Despite the sustained and improving test efforts in the field of driver development, DDs still represent a significant cause of system outages as the coverage is invariably limited by test resources and release time considerations. The basic factor is the inability to exhaustively assess and then cover the operational states, leading to releases of inadequately tested DDs. Consequently, if representative operational activity profiles of DDs within an OS could be obtained, these could significantly improve the understanding of the actual operational DD state space and help focus the test efforts. Focusing on characterizing DD operational activities while assuming no access to source code, this paper proposes a quantitative technique for profiling the runtime behavior of DDs using a set of occurrence and temporal metrics obtained via I/O traffic characterization. Such profiles are used to improve test adequacy against real-world workloads by enabling similarity quantification across them. The profiles also reveal execution hotspots in terms of DD functionalities activated in the field, thus allowing for dedicated test campaigns. A case study on actual Windows XP and Vista drivers using various performance and stability benchmarks as workloads substantiates our proposed approach. 相似文献
128.
L. E. Johansson 《Journal of the American Oil Chemists' Society》1980,57(1):16-22
Phase composition of a copper on silica gel catalyst was studied with X-ray diffraction analysis. Activity measurements showed
three periods of activity, the first two of which were ascribed to a copper surface subjected to reduction and the third one
to the reduced form of the catalyst. Hydrogenation reaction over Cu/SiO2 catalyst has a complex pressure dependence with a rate maximum at 6 atm in the low pressure range. Preparation of the catalyst
was studied. On the basis of a proposed reaction model, a catalyst mixture was prepared and tested with good results. In rapeseed
oil hydrogenation, Cu/SiO2 catalysts were shown to be superior to copper chromite catalysts. In soybean oil the two types of catalyst were rather equivalent. 相似文献
129.
Two ductile coating ma-terials were subjected to a combined indentation and scratch test procedure de-signed to screen a predetermined
pattern of many small sample surfaces in a limited time. The screening of 50 surface spots ordered in a matrix pattern on
the surface was carried out in 4.5 hr. The test provides reproducible data in terms of indentation modulus, elastic recovery,
scratch penetration depth, and scratch residual depth, and also offers the possibility of detecting critical mechanical transitions
such as rupture. The presented procedure produces sufficient data in a limited time scale to fulfill the requirements for
a fast method to screen coating compositions.
Dept. Polymer Technology, SE-100 44 Stockholm, Sweden.
Jaquet-Droz 1, CH-2007 Neuchatel, Switzerland. 相似文献
130.
Liang Li Anders Rasmuson Andy Ingram Mats Johansson Johan Remmelgas Christian von Corswant Staffan Folestad 《American Institute of Chemical Engineers》2015,61(3):756-768
Particle cycle and residence time distributions are critical factors in determining the coating quality in the Wurster process. Positron emission particle tracking experiments are performed to determine the cycle and residence times of particles in different regions of a Wurster fluid bed. The results show that particles tend to recirculate in and sneak out below from the Wurster tube. The experiments also show that a larger batch size leads to a shorter cycle time and a narrower cycle time distribution (CTD). It is possible to avoid recirculations and obtain a shorter cycle time and a narrower CTD by selecting the operating conditions appropriately or via equipment design. Experiments using binary mixtures of particles with a diameter ratio of 1.5 show that large particles have a longer cycle time than small particles and that the cycle time is shorter for mixtures with approximately equal amounts of small and large particles. © 2014 American Institute of Chemical Engineers AIChE J, 61: 756–768, 2015 相似文献