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261.
J S Spratt D P Alagia R A Greenberg J G Kuhns J B Buchanan J B Warren H C Polk 《Cancer》1985,55(6):1372-1375
The Breast Cancer Demonstration and Detection Project in Louisville (BCDDP-L) screened 10,128 women for cancer. From this screening, another project evolved wherein those patients diagnosed as having chronic cystic mastopathy (CCM) were followed over a 10-year period to evaluate any association between CCM and breast cancer. In all, 1396 breast biopsies were performed, with 165 cancers being diagnosed either on initial screening or during subsequent years. Three of these are excluded, since histopathologic slides could not be obtained for central review. Of this group, cancer was associated with CCM in 116 specimens and without CCM in 46 specimens. One subset of 355 patients with biopsy-proven CCM but no breast cancer was followed for 6 to 12 years, for a total of 2443.5 woman-years of observation. Within this subset, a total of only four cancers occurred (4 cancers/2443.5 woman-years for 0.00164 cancers/woman-years). This incidence is not significantly different from the expected value. However, an estimate is provided as to the power of the test that could be obtained from a larger sample size derived from other BCDDPs. This group of 355 women was sorted into subsets by establishing a matrix matching ten histopathologic subdivisions of CCM against six subdivisions of Wolfe's xeromammographic (XM) patterns. The numbers of cancers in each cell of this matrix is reported. The results found no concentration of these four cancers in this matrix. 相似文献
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Visualization of the suprasternal fossa in the newborn is due to suprasternal retraction. It is seen in 59% of patients with respiratory distress syndrome of the premature prior to intubation, and in 5% of patients with conditions such as pneumonia, meconium aspiration, and transient tachypnea of the newborn. The lower compliance of the lungs in patients with respiratory distress syndrome and increased compliance of the chest wall in premature infants accounts for the higher incidence of accentuation of the fossa. Visualization of the suprasternal fossa can simulate the distended proximal pouch of esophageal atresia. The two can be differentiated in the lateral view where the pretracheal location of the fossa can be appreciated. 相似文献
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The glycosyltransferases responsible for catalyzing additions of A, B, and H sugars to cellular acceptors were studied in 23 cases of primary carcinoma. The carcinomas were derived from mouth, tongue, larynx, lung, cervix, esophagus, stomach, and colon. Comparisons of A, B, and H enzymes were made between mucosal extracts from tumor and from normal adjacent tissue and, in the case of gastrointestinal tract, extracts derived from mucosae of individuals free of disease. The most prevalent finding was that of alpha-2-fucosyltransferase (H enzyme) deficiency in tumor extracts from Group A, B, and O patients in relation to the normal tissue counterpart (20 cases). Exceptions were observed in one case of carcinoma of the stomach and in two of seven cases of carcinoma of rectum or sigmoid. In four of nine Group A patients (carcinoma of the mouth, tongue, ascending and transverse colon), N-acetylgalactosaminyltransferases (A enzymes) were demonstrated but were deficient in relation to the normal adjacent counterpart. A enzymes were not demonstrable in normal and tumor extracts from distal colon in five cases. Differences between tumor extracts and normal adjacent tissue were noted in D-galactosyltransferase (B enzyme) derived from carcinomas of larynx and esophagus, but B enzyme was not demonstrated in tumor or normal tissue derived from the sigmoid colon. Study of the normal distribution of H enzyme in gastrointestinal mucosa indicated the presence of relatively high enzyme levels in stomach and upper intestine but low levels in distal colon. 相似文献
266.
A closer orientation of blood banking toward optimal donor and patient care will depend upon an enlargement of the manpower pool of physicians with specific competence in this area. Toward this end, programs must be developed within medical school curricula, and comprehensive postgraduate training programs must be available for those interested in committing themselves fully to this specialty. Continuing education must be made available to part-time blood banking professionals in order that they remain abreast of newer developments. Recognition of their skills can now come about through competence testing and certification programs. Improvements in management of the blood resource may then be expected to occur in parallel with the increase in numbers and quality of the professionals within this unique specialty. 相似文献
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The effect of various air gaps on computed radiographic musculoskeletal images was investigated using a knee phantom. Scatter
to primary radiation ratios were measured using the beam stop method at air gaps ranging from 0 to 30 in. (0–762-mm). Bony
trabecular sharpness, line pair resolution, quantum mottle and visualization of low-contrast beads in the soft tissues were
evaluated. A significant reduction of scatter to primary radiation ratio, from a value of almost 1 at table top to about 0.4
at 10-in. (254-mm) air gap and about 0.2 at 25-in. (635-mm) air gap placement of the computed radiography (CR) imaging plate,
was obtained. A progressive improvement in bony trabecular sharpness and line pair resolution, compared with the table top
and Bucky images was observed on 10-in. (254-mm) through 25-in. (635-mm) air gap images. Sharpness of the bony trabeculae
and line pair resolution were best on the 25-in. (635-mm) air gap images. The skin entrance radiation dose does not have to be increased for air gap digital radiography. The radiographic noise or quantum mottle is highest on the Bucky image,
higher on air gap images and minimal on the table top images, despite a high scatter to primary radiation ratio at the table
top. The lower quantum mottle on the table top images allowed for maximal visualization of low contrast densities in the soft
tissues. Air gap radiography further improves musculoskeletal computed imaging by reducing the scatter to primary radiation
ratio without an increase in the skin entrance dose. For significant reduction of the scatter to primary radiation ratio and
best evaluation of line pair spatial resolution and bony trabeculae, a 25-in. (635-mm) air gap with digital radiography would
be optimal. For evaluation of low contrast densities in the soft tissues, table top placement would be the technique of choice.
Received: 29 December 1995 Accepted: 27 March 1996 相似文献