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81.
S Battersby B J Robertson T J Anderson R J King K McPherson 《British journal of cancer》1992,65(4):601-607
Steroid receptor was assessed immunohistochemically in 158 samples of normal breast for variation through the menstrual cycle. Patterns and intensity of reaction were used in a semi-quantitative scoring system to examine the influence of cycle phase, cycle type, parity and age. The changes in oestrogen receptor for natural cycle and oral contraceptive (OC) cycles indicated down-regulation by progestins. Progesterone receptor did not vary significantly in natural cycles, but increased steadily through OC cycles. This study provides strong evidence that both oestrogen and progesterone influence breast epithelium, but dissimilarities from the endometrium are apparent. The interval since pregnancy had a significant negative effect on frequency and score of oestrogen receptor and score of progesterone receptor. Multivariate analysis established the phase of cycle and OC use as independent significant influences on oestrogen receptor. The interval since pregnancy was an independent significant factor for both oestrogen and progesterone receptor presence. 相似文献
82.
Drinking History Is Related to Persistent Blood Pressure Dysregulation in Postwithdrawal Alcoholics 总被引:1,自引:1,他引:0
Andrea C. King Oscar A. Parsons Nancy C. Bernardy William R. Lovallo 《Alcoholism, clinical and experimental research》1994,18(5):1172-1176
We have previously demonstrated that alcoholics with transitory (< 72 hr) elevations in blood pressure (BP) during withdrawal continue to show residual cardiovascular dysregulation up to 4 weeks of abstinence. The present study replicates and extends these findings. Alcoholic inpatients were divided into three subgroups ( ns = 14) based on BP during the first 72 hr of withdrawal: transitory hypertensives (tHTs; BP > 160/95 mm Hg), transitory borderline hypertensives (tBHs; 140/90 BP < 160/95), and normotensives (NTs; all BPs < 140/90). All patients had normal resting pressures after 72 hr of withdrawal. At 3–4 weeks postadmission, the alcoholics and 14 nonalcoholic controls (CONTs) were tested at rest and during a 5-min handgrip task. The tHTs showed an exaggerated systolic and diastolic BP response to handgrip compared with NTs and CONTs, with tBHs intermediate ( ps < 0.05). Drinking history showed the tHTs had the highest reported level of alcohol consumption and severity of withdrawal symptoms ( ps < 0.05). Regression analyses indicated that consumption of hard liquor was the variable most predictive of admission BPs; further, parental history of hypertension potentiated this relationship for systolic BP. Age and consumption of nicotine and caffeine were not significant predictors of admission BP. The results suggest a persistent cardiovascular dysregulation in alcoholics showing transient hypertensive withdrawal BPs. These alcoholics may be at increased risk for future alcohol-related cardiovascular disorder. 相似文献
83.
Training in élite young athletes (the Training of Young Athletes (TOYA) Study): injuries, flexibility and isometric strength.
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Using a mixed longitudinal design, the incidence of injuries, and the development of flexibility and isometric strength of the upper and lower limbs were studied for 2 years in 453 élite young athletes (aged between 9 and 18 years) practising football, gymnastics, swimming or tennis. The children suffered from a low incidence of injuries. Strength and flexibility did not exert a significant role in determining injuries. The rate of injury was not significantly different between the 2 years of the study. Young swimmers showed a greater generalized flexibility. Girls were more flexible than boys between the ages of 13 to 16 years. Athletic children are able to exert greater isometric strength than normal schoolchildren. Boys diverged from the normal population at 14 years, while athletic girls were stronger at all ages. Girls were stronger than boys up to age 12, who were still increasing their muscle strength at 19 years. The average maximal isometric strength exerted in both upper and lower limbs in the four sports was not significantly different. Male gymnasts over 11 years old were significantly stronger than all other athletes. 相似文献
84.
David P. Faxon David Holmes Geoffrey Hartzler Spencer B. King Gerald Dorros 《Catheterization and cardiovascular interventions》1992,25(1):1-3
At present, the majority of cardiac catheterization laboratories acquire and store hemo-dynamic data in analog form. To examine the possibility of performing complex analysis of digital data during the catheterization procedure, we examined whether virtual realtime digital (fast Fourier) analysis improves the accuracy of clinical data. We compared digital filtering of fluid manometry during right heart catheterization with 10-Hz and 250-Hz analog filters. Using the simultaneously acquired micromanometry as the “gold standard,” we found that analog filtering is associated with a greater error and time delay than digital filtering. This study demonstrates that digital hemodynamic data analysis performed during cardiac catheterization can improve the quality of data obtained during right heart catheterization, with the results available within seconds. More extensive use of computers in the cardiac catheterization laboratory may be useful for both clinical and research purposes. © 1992 Wiley-Liss, Inc. 相似文献
85.
L P Clarke S J Cullom R Shaw C Reece B C Penney M A King M Silbiger 《Journal of nuclear medicine》1992,33(1):161-166
Quantitative imaging of bremsstrahlung from pure beta emitters is proposed as a means for in vivo management of antibody therapy. The method involves the use of high-energy collimation, an empirically selected broad photon energy window to enhance detector sensitivity, and a Wiener restoration filter to compensate for system blur. The measured and filtered data were obtained for an idealized scattering medium and isolated spherical sources. An effective linear attenuation coefficient of about 0.13 cm-1 was determined from the raw image data of 32P. A coefficient of 0.14 cm-1 was determined after the images were restored using the Wiener filter. The measured attenuation was not significantly dependent on the size of the region of interest or the size of the source. Its variation was within the experimental error of measurement (+/- 5%). The measured sensitivity (6 x 10(-6) cps/Bq) was sufficient for imaging therapy doses of 32P or 90Y. 相似文献
86.
87.
Several peptides have been localized within afferents to the opossum's cerebellum, including cholecystokinin (15), enkephalin (16, 17) and corticotropin releasing factor (7, 9). Each of these peptides has a heterogeneous laminar and lobular distribution. Two peptide, enkephalin (ENK) and corticotropin releasing factor (CRF) are present in specific populations of climbing fibers and mossy fibers, which have an overlapping distribution in several areas of the cerebellum, in particular the lateral aspect of vermal lobules VII and VIII. Within this location ENK and CRF are co-localized in individual climbing fibers and mossy fibers (7). In the present study, the physiological effects of these peptides on Purkinje cell activity were analyzed. The data indicate that ENK and CRF have opposite effects on Purkinje cell activity. ENK suppresses spontaneous activity as well as that induced by application of glutamate and aspartate, as described previously (5). In contrast, CRF enhances both spontaneous and amino acid-induced unit activity. Further, when applied simultaneously, CRF blocks the suppressive effect induced by ENK. Previous studies have shown that climbing fibers, as well as the mossy fiber-parallel fiber pathway, are excitatory to Purkinje cells (11). However, immunohistochemical data have shown that these afferents are heterogeneous with respect to their chemical content (7-9, 15-17, 25). As found in the current and previous studies (3, 5) peptides in climbing and mossy fibers modulate the responsiveness of Purkinje cells to primary excitatory neurotransmitters in selected areas of the cerebellar cortex. However, the firing rate of individual Purkinje cells is differentially altered depending on which neurochemical messenger(s) are released.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
88.
89.
This paper examines two approaches for the analysis of quantitative traits: (1) association studies and (2) linkage studies. The trait studied was Q1 from simulated Problem 2 data set in Genetic Analysis Workshop 9. Our purpose was to evaluate associations present in the data, to identify nongenetic and genetic predictors of the trait, and to explore the simulated genome for linkage. Through the association study, we found evidence for the primary major gene associated with this trait. The linkage study found evidence of residual genetic effect acting through other traits. Adjustments of Q1 for Q2 and Q3 led to a failure to find significant effects of MG2 and MG3. This supports the suggestion that adjustment for genetically influenced traits for effects of other genetic traits can reduce the power to detect major gene effects. In summary, we detected the major gene directly associated with the trait of interest through association studies. Linkage analysis detected evidence for two other genes associated to a lesser degree with the trait. © 1995 Wiley-Liss, Inc. 相似文献
90.