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991.
Folate, vitamin B2 (riboflavin), and vitamin B12 may affect bone directly or through an effect on plasma homocysteine levels. Previously, a positive association has been found between plasma levels and bone mineral density (BMD) as well as risk of fracture. However, there are limited data on whether dietary intakes affect bone. Our aim was to investigate whether intake of folate, vitamin B2, and vitamin B12, as assessed by food records affects BMD and fracture risk. In a population-based cohort including 1,869 perimenopausal women from the Danish Osteoporosis Prevention Study, associations between intakes and BMD were assessed at baseline and after 5 years of follow-up. Moreover, associations between intakes and 5- and 10-year changes in BMD as well as risk of fracture were studied. Intakes of folate, vitamin B2, and vitamin B12 were 417 (range 290–494) μg/day, 2.70 (range 1.70–3.16) mg/day, and 4.98 (range 3.83–6.62) μg/day, respectively, i.e., slightly above the intakes recommended by the United Nations Food and Agriculture Organization. At year 5, but not at baseline, cross-sectional analyses showed positive correlations between daily intake from diet and from diet plus supplements of folate and BMD at the femoral neck (P < 0.01). However, no associations were found between intakes and changes in BMD. During 10 years of follow-up, 360 subjects sustained a fracture. Compared with 1,440 controls, logistic regression analyses revealed no difference in intakes between cases and controls. A high dietary intake of folate, but not vitamin B2 or B12, exerts positive effects on BMD; but further studies are needed to confirm this association.  相似文献   
992.
Adnexal and cul-de-sac abnormalities: transvaginal sonography   总被引:1,自引:0,他引:1  
Lande  IM; Hill  MC; Cosco  FE; Kator  NN 《Radiology》1988,166(2):325-332
Sixty-seven patients selectively chosen from 354 undergoing conventional transabdominal (TA) sonography for evaluation of a clinically suspected adnexal mass subsequently underwent transvaginal (TV) sonography either because the TA sonograms were technically suboptimal or because it was not possible to characterize with certainty an abnormality identified with TA sonography. TV sonography added diagnostically useful information in 25 of 28 patients with cystic pathologic changes in the adnexa uteri. Eight of 12 patients with tuboovarian abscess and nonspecific adnexal masses visualized with TA sonography had tube-shaped fluid collections characteristic of pyosalpinx identified with TV sonography. TV sonography added diagnostically useful information in all seven patients with diseases of the cul-de-sac (rectouterine fossa) and allowed differentiation of adnexal from primary uterine disease in three patients with TA sonograms on which findings were equivocal. It also expedited the diagnosis of a tubal pregnancy in ten of 14 patients and was useful in the detection of adhesions and perforated intrauterine devices. These results indicate that adjunctive TV sonography can provide important diagnostic information.  相似文献   
993.
In a 1 year period, 13 patients underwent pump implantation for liver metastasis from a primary colorectal tumor. The gallbladders were not removed at the time of pump implantation in the initial six patients. In these patients, chemotherapy consisted of floxuridine given every 2 weeks followed by a 2 week rest period and cisplatin over 1 hour by way of the side portal on day 8 of the cycle. The treatment was repeated every 28 days. All patients whose gallbladders were not removed at the time of pump implantation required reoperation for acute or chronic acalculous cholecystitis from 1 to 9 months (mean 5.4 months) after pump implantation. At operation, all patients were found to have various degrees of inflammation and fibrosis. In one patient, significant sclerosing cholangitis was documented that involved the entire intrahepatic ductal system and hepatic duct bifurcation. Cholecystectomy and operative cholangiography are recommended in all patients who undergo pump implantation for metastatic disease to the liver.  相似文献   
994.
995.
HYPOTHESIS: A newly developed hydrostatic anti-G suit is now commercially available. The suit is said to offer a high level of protection against +Gz acceleration. However, past experience shows that it is difficult to produce a hydrostatic suit with effective high-G protection. Careful testing is, therefore, needed to verify its efficacy. METHODS: The G-protective properties of the hydrostatic anti-G suit (Libelle; L) were compared with those of a pneumatic anti-G ensemble (AGE-39) used in the Swedish JAS 39 Cripen aircraft. Three pilots were studied during vertical (+Gz) acceleration in a centrifuge using the following: 1) the L-suit with varied straining maneuvers; 2) the AGE-39 in combination with full anti-G straining maneuvers (AGSM) throughout each high-G exposure (full maneuver; FM); and 3) the AGE-39 in combination with AGSM during the initial part of each high-G exposure (reduced maneuver; RM). G-intensity tolerance was established during exposures to rapid onset rate (ROR) profiles with G-plateau levels ranging from +6.0 to +9.0 Gz. G-endurance was studied during simulated aerial combat maneuvers (SACM) consisting of 10 cycles of 5.5 to 7.5 G. RESULTS: All three pilots tolerated 9.0 G with the pneumatic system both in the RM and FM conditions; their tolerances averaged 6.3 G (range 6.0 to 7.0 G) for the L suit. Thus, during the ROR exposures only the 6.0 G profile was completed by all subjects in all three conditions. At this G-load both muscle straining (as indicated by electromyographic activity in thigh and abdomen) and heart rate were higher in the L than in the RM condition. Mean arterial pressure at eye level was higher in the FM than in the L and RM conditions. Only one subject was able to complete the SACM profile in the L condition. In the RM condition all subjects completed the SACM profile and in the FM condition two subjects completed the SACM. CONCLUSIONS: Whether the AGE-39 was used in combination with maximal AGSM throughout the duration of each high-G exposure or with AGSM only during the initial part of the high-G exposure, G-intensity tolerance was 9.0 G. While wearing the L-suit, G-tolerance was 6.3 G. Thus, under the conditions tested, the G-protection afforded by the L-suit is not adequate for use in a 9-G aircraft.  相似文献   
996.
Bacterial renal infection: role of CT   总被引:2,自引:0,他引:2  
Soulen  MC; Fishman  EK; Goldman  SM; Gatewood  OM 《Radiology》1989,171(3):703-707
The imaging studies done on 62 patients hospitalized for acute renal infections were retrospectively reviewed. Thirty-six (58%) had one or more abscesses, 17 (27%) had focal or diffuse acute bacterial nephritis, five (8%) had pyonephrosis, and four (6%) had pyelonephritis. All had prolonged fever (greater than or equal to 72 hours) and leukocytosis. Among 25 patients examined with both ultrasound (US) and computed tomography (CT), US failed to depict three of five (60%) cases of acute bacterial nephritis and seven of 15 (47%) intrarenal and extrarenal abscesses. One renal abscess was misdiagnosed as a tumor at CT. US is not an adequate screening test for detecting lesions that may require invasive therapy. CT is more sensitive for the detection of acute renal inflammatory disease and for defining the extent of disease for planning of radiologic or surgical intervention.  相似文献   
997.
998.
Bugmyrin  S. V.  Tirronen  K. F.  Panchenko  D. V.  Kopatz  A.  Hagen  S. B.  Eiken  H. G.  Kuznetsova  A. S. 《Parasitology research》2017,116(6):1755-1760

We present data on the species composition of helminths in brown bears (Ursus arctos) from the Murmansk Region, Russia. The absence of any information about helminths of brown bear in the region necessitated the conduct of these studies. Samples were collected in 2014 and 2015 in the southern part of the Kola Peninsula from the White Sea coastal habitats. Annually, in the study area, 1–3 bears are legally hunted and biological samples for examination are very difficult to obtain. Therefore, we used fecal samples. We studied 93 feces and identified parasite eggs identified in 43 of them by morphometric criteria. The surveys revealed eggs of the following helminths: Dicrocoelium sp., Diphyllobothrium sp., Anoplocephalidae, Capillariidae, Baylisascaris sp., Strongylida 1, and Strongylida 2. These results represent the first reconnaissance stage, which allowed characterizing the taxonomic diversity and prevalence of parasites of brown bears of the Kola Peninsula.

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999.
1000.
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