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101.
102.
Concern about environmental pollutants has increased; however, it remains unclear whether chronic exposures to toxic chemicals in the environment occur at doses sufficient to produce adverse health effects in humans. To date, community studies have not adequately addressed this question. In this study, the authors linked two existing data bases of the New York State Department of Health to evaluate the relation between congenital malformations and residential proximity to hazardous waste sites in New York State. A total of 9,313 newborns with congenital malformations and 17,802 healthy controls living in proximity to 590 hazardous waste sites in 1983 and 1984 were evaluated. After the authors controlled for several possible confounding factors, results indicated that maternal proximity to hazardous waste sites may carry a small additional risk of bearing children with congenital malformations (odds ratio (OR) = 1.12, 95% confidence interval (Cl) 1.06-1.18). Higher malformation rates were associated with both a higher exposure risk (no exposure risk: OR = 1.00; low exposure risk: OR = 1.09, 95% Cl 1.04-1.15; high exposure risk: OR = 1.63, 95% Cl 1.34-1.99) and documentation of off-site chemical leaks (not exposed: OR = 1.00; exposed, but no leaks at site: OR = 1.08, 95% Cl 1.02-1.15; exposed, and leaks found at site: OR = 1.17, 95% Cl 1.08-1.27). The increased rates detected may be important in terms of their public health implications. Further research is necessary to strengthen causal inferences regarding the teratogenicity, of waste site exposure.  相似文献   
103.
Background and purpose — Reverse shoulder arthroplasty (RSA) has become the treatment of choice for cuff-tear arthropathy. There are, however, concerns about the longevity and the outcome of an eventual revision procedure. Thus, resurfacing hemiarthroplasty (RHA) with extended articular surface has been suggested for younger patients. We compared the patient-reported outcome of these arthroplasty designs for cuff-tear arthropathy.

Patients and methods — We included patients operated on because of cuff-tear arthropathy and reported to the Danish Shoulder Arthroplasty Registry (DSR) from January 1, 2006 to December 31, 2013. 117 RHA cases were matched by age and sex with 233 RSA controls. 34 of the RHAs were conventional and 67 were RHAs with extended articular surface. The Western Ontario Osteoarthritis of the Shoulder (WOOS) Index at 1 year was used as primary outcome. The score was converted to a percentage of a maximum score. Revision, defined as removal or exchange of any component or the addition of a glenoid component, was used as secondary outcome.

Results — Median WOOS was 49 (30–81) for RHA and 77 (50–92) for RSA (p < 0.001). For patients younger than 65 years, median WOOS was 58 (44–80) after RHA, similar to the 54 after RSA (37–85). For patients older than 65 years, median WOOS was 48 (28–82) after RHA and 79 (55–92) after RSA (p < 0.001).

Interpretation — In all patients RSA had a clinically and statistically better patient-reported outcome than RHA. However, in patients younger than 65 years the functional outcome was similar and poor for either arthroplasty type. The optimal treatment of CTA in young patients remains a challenge.  相似文献   

104.
105.
J A Olsen  F B Loud    J Christiansen 《Gut》1987,28(4):464-467
A dose response study of the effect of an octapeptide somatostatin analogue, SMS 201-995, on meal stimulated gastric acid secretion was carried out in 12 healthy volunteers. Infusion of SMS 201-995 in a dose of 50 pmol/kg/h almost completely abolished the acid response to the meal. Pl-gastrin was significantly decreased during infusion of 10 pmol/kg/h of SMS 201-995 and insulin was significantly inhibited during infusion of 50 pmol/kg/h. SMS 201-995 in a dose of 50 pmol/kg/h inhibited basal and submaximal pentagastrin stimulated acid secretion by 77% and 84% respectively (p less than 0.01). On a molar basis SMS 201-995 is substantially more potent than natural somatostatin in inhibiting gastric acid secretion.  相似文献   
106.
In vivo studies of intestinal carnitine absorption in rats   总被引:2,自引:0,他引:2  
We have studied small intestinal absorption of carnitine in vivo using a combination of segmental perfusion techniques and bolus intraluminal injection. We found evidence of a partially saturable absorption process (with Km values of 1035 and 1267 microM for jejunum and ileum calculated for the saturable component) that appeared to be separate from the imino acid transport system. Absorption was characterized by slow mucosal uptake, prolonged mucosal retention, and a very slow mucosal exit process with blood levels of [3H] carnitine still rising 8 h after intraluminal administration. We have also demonstrated the presence of carnitine acetyltransferase in intestinal mucosa and have shown that the intestine forms significant amounts of acetylcarnitine from exogenous carnitine.  相似文献   
107.
The natural history of functional morbidity in hospitalized older patients   总被引:7,自引:1,他引:7  
This study provides data on changes in the functional status of older patients that are associated with acute hospitalization. Seventy-one patients over the age of 74 admitted to the medical service of Stanford University Hospital between February and May 1987 received functional assessments covering seven domains: mobility, transfer, toileting, incontinence, feeding, grooming, and mental status. Assessments were obtained by report from the patient's caregiver (or the patient when he or she lived alone) for 2 weeks before admission; from the patient's nurse on day 2 of hospitalization and on the day before discharge; and again from the caregiver (or patient) 1 week after discharge. The sample had a mean age of 84, covered 37 Diagnostic Related Groups, and had a median length of stay of 8 days. Between baseline and day 2, statistically significant deteriorations occurred for the overall functional score and for the individual scores for mobility, transfer, toileting, feeding, and grooming. None of these scores improved significantly by discharge. In the case of mobility, 65% of the patients experienced a decline in score between baseline and day 2. Between day 2 and discharge, 67% showed no improvement, and another 10% deteriorated further. These data suggest that older patients may experience a burden of new and worsened functional impairment during hospitalization that improves at a much slower rate than the acute illness. An awareness of delayed functional recovery should influence discharge planning for older patients. Greater efforts to prevent functional decline in the hospitalized older patient may be warranted.  相似文献   
108.
Eight laboratories in six countries cooperated to clarify several issues concerning the phenotypes of heterozygous carriers of hemophilia "A." Plasma levels of factor VIII (F.VIII:C, formerly VIII:C) and von Willebrand factor (VWF:Ag, formerly VIIIR:Ag) of carriers and normal women were determined by various "in-house" methods; a single lyophilized plasma standard was used for all assays. Analysis of the collated data from 336 carriers (296 obligatory carriers and 40 sporadic carriers) and 137 normal women showed that there was no difference in the F.VIII:C levels of "paternal" carriers (women who had obtained the abnormal gene from their fathers) and "maternal" carriers. Neither was there a difference in the VWF:Ag levels of normal women and either type of carrier. Age was found to have a significant effect on both F.VIII:C and VWF:Ag, values being higher at very young and very old ages, the minima occurring in the 25- to 30-year range. ABO blood type had a striking effect. Women of types A, B, and AB (designated non- O in the study), both normals and carriers, had significantly higher levels of both factors than did women of type O. Analysis by laboratories showed that differences in mean levels of both factors between laboratories were highly significant. It was concluded that age, ABO blood type, and laboratory variation should be taken into account in carrier detection.  相似文献   
109.
Shami  PJ; Weinberg  JB 《Blood》1996,87(3):977-982
Nitric oxide (NO) is a reactive molecule with numerous physiologic and pathophysiologic roles affecting the nervous, cardiovascular, and immune systems. In previous work, we have demonstrated that NO inhibits the growth and induces the monocytic differentiation of cells of the HL- 60 cell line. We have also demonstrated that NO inhibits the growth of acute nonlymphocytic leukemia cells freshly isolated from untreated patients and increases monocytic differentiation antigens in some. In the present work, we studied the effect of NO on the growth and differentiation of normal human bone marrow cells in vitro. Mononuclear cells isolated from human bone marrow were cultured in semisolid media and treated with the NO-donating agents sodium nitroprusside (SNP) or S- nitroso-acetyl penicillamine (SNAP) (0.25 to 1 mmol/L). Both agents decreased colony-forming unit-erythroid (CFU-E) and colony-forming unit- granulocyte macrophage (CFU-GM) formation by 34% to 100%. When CD34+ cells were examined, we noted that these cells responded to SNP and SNAP differently than did the mononuclear cells. At a concentration range of 0.25 to 1 mmol/L, SNP inhibited the growth of CFU-E by 30% to 75%. However, at the same concentration range, SNP increased the number of CFU-GM by up to 94%. At concentrations of 0.25 to 1 mmol/L, SNAP inhibited the growth of CFU-E by 33% to 100%. At a concentration of 0.25 mmol/L, SNAP did not affect CFU-GM. At higher concentrations, SNAP inhibited the growth of CFU-GM. Although SNP increased intracellular levels of cGMP in bone marrow cells, increasing cGMP in cells by addition of 8-Br-cGMP (a membrane permeable cGMP analogue) did not reproduce the observed NO effects on bone marrow colonies. These results demonstrate that NO can influence the growth and differentiation of normal human bone marrow cells. NO (generated in the bone marrow microenvironment) may play an important role modulating the growth and differentiation of bone marrow cells in vivo.  相似文献   
110.
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