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In some patients with chronic renal failure, bone mineralization becomes defective after parathyroidectomy for secondary hyperparathyroidism. Because aluminum deposition in bone is associated with impaired bone formation and osteomalacia, we retrospectively studied bone-biopsy specimens from patients on hemodialysis who were not exposed to dialysate contaminated with aluminum, to determine whether aluminum accumulation on bone surfaces was enhanced by parathyroidectomy. Serial biopsy specimens taken before and after parathyroidectomy revealed an increase in the rate of aluminum deposition on the surface of mineralized bone after parathyroidectomy in each of the six patients studied. The accelerated rate of aluminum accumulation could not be explained by changes in the oral aluminum intake. The mean rate of bone formation (+/- S.E.M.) before parathyroidectomy was higher in the six patients than in six control patients who did not undergo parathyroid surgery (586 +/- 147 vs. 237 +/- 85 micron2 per square millimeter per day; P less than 0.05). After parathyroidectomy, the rate of bone formation fell to levels below normal (148 +/- 32 vs. 311 +/- 29 micron2 per square millimeter per day; P less than 0.05) but was not significantly different from the rate in the control group (319 +/- 126 micron2 per square millimeter per day). We conclude that parathyroidectomy in patients with chronic renal failure is associated with enhanced aluminum deposition on the bone surface, possibly as a result of low bone formation. Patients with secondary hyperparathyroidism who may be candidates for parathyroidectomy should be evaluated for aluminum excess before surgery, so that treatment with aluminum chelation may be considered.  相似文献   
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Naive T cells after allogeneic hematopoietic cell transplantation are thought to originate from the engrafted hematopoietic cells. In this report, we show that there is a correlation between the number of naive CD4 T cells infused with peripheral blood stem cell grafts and the absolute number of peripheral naive CD4 T cells on day 30 (R = 0.65; P <.001), day 80 (R = 0.63; P <.001), and day 180 (R = 0.66; P <.001) after transplantation. These results suggest that in the first 6 months after transplantation, most naive CD4 T cells are derived from the naive T cells infused with the graft.  相似文献   
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We tested 10 patient sera for the presence of immunoglobulin G (IgG) antibodies to Candida albicans and for C. albicans antigens by immunoblot analysis (i.e., electrotransfer blot radioimmunoassay) (G. E. Smith and M. D. Summers, J. Virol. 39:125-137, 1981). We evaluated sera from two patients at risk for candidiasis, five patients with systemic candidiasis documented by culture, and two patients who had experienced transient candidemia. Both the specificity and the relative amount of IgG antibodies to C. albicans in each serum sample were readily visualized by this technique, as was the absence of antibody from serum of neonatal and immunocompromised patients. No antibody species appeared to be uniquely associated with candidiasis patients (i.e., each antibody species present in the candidiasis patient was also present in sera of normal individuals or "at-risk" patients). IgG from rabbits immunized with whole cells or with a cytoplasmic fraction of C. albicans was used to detect C. albicans antigens in patient sera. Although several antigens were detected in the sera from patients with candidiasis, the same antigens were also detected in sera from patients at risk and in normal human serum. No antigens were detected in human serum when preimmune rabbit sera were used. These results suggest that the antigens detected by the rabbit antisera were human serum proteins that cross-reacted with C. albicans antigens. These findings may have important implications in studies of both the pathobiology of C. albicans and the serodiagnosis of candidiasis.  相似文献   
15.
Tiopinac displayed marked anti-inflammatory activity when given p.o. in rat models of acute and chronic inflammation. It inhibited carrageenan-induced paw edema (40 x phenylbutazone), and cotton-pellet-induced granuloma (0.8 x indomethacin). In an 18-day test, tiopinac prevented the development of adjuvant-induced arthritis (10–15 x naproxen) and had similar activity versus pre-induced arthritis. Tiopinac exhibited antiphlogistic activity in adrenalectomized rats. It did not have corticosteroid activity. Depending upon the type of analgesic test used, the potency of tiopinac varied. When given p.o. it inhibited henylquinone-induced writhing in the mouse and rat (respectively 16 and 10 x aspirin). In contrast, tiopinac had 10 times the potency of indomethacin in increasing the pain threshold when yeast-inflamed paws were compressed. The pain threshold of the noninflamed paw was not increased. Tiopinac was highly active versus pain induced by flexing the adjuvant arthritic-inflamed paw (1000 x aspirin). It was inactive in the mouse hotplate test in which opiate-like agents are active. Tiopinac, p.o., lowered yeast-induced pyrexia (130 x aspirin). Tiopinac did not have significant cardiovascular or CNS activity. Whereas the ED50 versus adjuvant arthritis in rats was 0.1 mg/kg/day p.o., rats tolerated up to 20 mg/kg/day p.o. in the 8-day cotton-pellet test. Lack of anorexia and emesis in dogs with up to 30 mg/kg p.o. and mild oral activity in producing gastric erosion in acute and subacute studies in rats suggests that tiopinac may have relatively little gastrointestinal irritating activity.A preliminary presentation of this study was delivered at the Federation of American Societies of Experimental Biology Meeting, Atlantic City, N.J., 1978 (Fed. Proc.37, 662 (1978).  相似文献   
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Prevention Science - There is evidence that universal school-based mindfulness training (SBMT) can have positive effects for young people. However, it is unknown who benefits most from such...  相似文献   
17.
In the United States, all newly developed drugs undergo a lengthy review process conducted by the US Food and Drug Administration (FDA). These regulatory delays have direct immediate costs for drug manufacturers and patients waiting for treatment. Under certain market conditions, regulatory delays may also affect future research and development (R&D) strategies of pharmaceutical companies. To estimate the magnitude of this effect, we match data on drugs in the development pipeline in 2006 to data that we collect on FDA review times for all drugs approved between 1999 and 2005. Employing a rich and novel set of controls that affect drug R&D decisions and, potentially, regulatory review lags, we find that on average, three additional months of delay result in one fewer drug in development in that drug category. Our results suggest that the length of the regulatory delay matters for pharmaceutical firms' R&D decisions and that the firms are likely unable to pass on these costs onto consumers.  相似文献   
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Severe respiratory sequelae drive morbidity-associated with coronavirus 2019 (COVID-19) disease. We report a case of COVID-19 pneumonia complicated by cavitary lesions and pneumothorax in a young healthy male. Pneumothorax management with catheter thoracostomy and rapid resolution of the cavitary lesions are described. An extensive work-up for other causes a cavitation was negative and the temporal correlation of the cavities with COVID-19 infection plus their rapid resolution suggest a direct relationship. We propose a mechanism for cavitation secondary to microangiopathy, a cause of cavitation in the vasculitides and a known feature of COVID-19.  相似文献   
20.
Continued progress over the next decade in reducing premature morbidity and mortality from chronic disease will require that health communication efforts target a significant proportion of the American public that has not been influenced by the health promotion efforts of the 1980s. Focus groups conducted with members of the hard-to-reach American public showed that while being healthy seemed to be important to participants, and they were generally aware of what to do to stay healthy, they had a different operational definition of health than that used in health promotion programs. Participants seemed to believe that better health behaviors would build their resistance to acute illnesses, that is, keep them healthy, but that chronic diseases, such as cancer and diabetes, were due to fate and heredity and beyond their individual control. The focus group results show that participants had not made the link between chronic disease prevention and the importance of diet, exercise, and weight control. Although most of them seemed to express a genuine interest in "doing better," they were not able to supply more than superficial examples of how such changes might be made. Surprisingly, there were more similarities than differences in participants' attitudes and beliefs, with the similarities cutting across boundaries of race-ethnicity, age, and sex. Interest in changing behaviors was only slightly more pronounced among female rather than male, and older rather than younger, participants. However, there was not much evidence from the participants that they were actively seeking health information or trying to reconcile conflicting knowledge and beliefs.  相似文献   
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