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排序方式: 共有2238条查询结果,搜索用时 15 毫秒
181.
CF Hildebolt TK Pilgram M Dotson N Yokoyama-Crothers J Muckerman J Hauser S Cohen E Kardaris MW Vannier P Hanes MK Shrout R Civitelli 《Canadian Metallurgical Quarterly》1997,32(7):619-625
To determine whether postmenopausal bone loss and factors associated with osteoporosis affect tooth retention, we examined vertebral and proximal femoral (postcranial) bone mineral density in relation to tooth loss and attachment loss in a cross-sectional study of 135 postmenopausal women (age range 41-70 yr). Women had at least 10 teeth and no evidence of moderate or severe periodontal disease. Full-mouth attachment loss measurements were made using a pressure-sensitive probe, and bone density was determined by dual-energy X-ray absorptiometry. Attachment loss was correlated with tooth loss (number of remaining teeth, radiologically determined), but not with vertebral or proximal femur bone density. Multivariate analysis showed current smoking (p = 0.01), years since menopause (p = 0.02) and the interaction of age and current smoking (p < 0.01), to be statistically significant predictors of attachment loss in our study population. 相似文献
182.
The influence of irradiation on biosyntheses of ascorbic acid and riboflavin in germinating chickpea seeds at ambient (25-35℃) conditions, was investigated. The rate of syntheses of these vitamins significantly increased with increasing germination time upto 120 h depending upon the treatment (P<0.05). Maximum amounts of ascorbic acid, 22.32 and 16.84 mg/100g, were found in the 0.10 kGy sample after 120 h of germination in tap and distilled water respectively. However, a radiation dose of 0.15 kGy resulted in the development of maximum values of riboflavin, 11.40 and 11.38 μ g/g, on germination in tap and distilled water respectively. A significant linear relation (r = 0-954 to 0.997) was observed between the biosyntheses of these vitamins and the germination time upto 120 h of irradiated and unirradiated chickpea seed (P<0.05). 相似文献
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A method is described for the densitometric determination of the p-hydroxybenzoic esters and p-hydroxybenzoic acid in mixtures or in drugs. This method is compared with the one used in high performance liquid chromatography (HPLC). The calibration curves were linear in interval 0.250-3.60 mumol ml-1 per 200 nl per spot. The limit of detection and the relative standard deviation (RSD) are higher than in HPLC (RSD is 6% in HPTLC. 3% in HPLC; limit of detection about 40 pmol in HPTLC and 25 pmol in HPLC) but HPTLC quantitative determination of parabens in drugs is faster. 相似文献
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BACKGROUND: Few references exist regarding contemporary complications of pyloromyotomy (PM) for infantile hypertrophic pyloric stenosis (IHPS). Therefore, we reviewed the frequency and outcome of patients with IHPS who developed complications from PM. METHOD: A 25-year retrospective review was performed in two populations. The first group included all infants who had a PM for IHPS at two pediatric surgery centers. The second group included all infants referred from other institutions who developed complications following PM for IHPS. RESULTS: Between 1969 and 1994, 901 PMs were performed. Intraoperative complications occurred in 40 patients (4%), including 39 duodenal perforations and 1 difficult intubation requiring prolonged ventilation. No unrecognized duodenal perforations or incomplete PMs were found. Postoperative complications developed in 52 patients (6%). The wound infection rate was less than 1%. Postoperative vomiting occurred in 31 infants (3%). The mortality rate was 0.1%, with 1 death due to sepsis from delayed diagnosis of Hirschsprung's disease. During the same study period, 11 patients were referred from other hospitals for postoperative complications. Five had persistent vomiting treated successfully with expectant management. Six infants needed reoperation: 3 for persistent IHPS, 1 for gastric outlet obstruction, and 1 for small bowel obstruction secondary to adhesions; 1 required wound abscess drainage. CONCLUSION: Pyloromyotomy is not without complications. Duodenal perforation should be infrequent, but when it occurs, it can usually be readily recognized and treated with minimal morbidity. Postoperative vomiting can be managed nonoperatively, but if it persists longer than 5 days, radiologic evaluation should be performed. Incomplete PM is uncommon and should not occur. A second myotomy is needed when the diagnosis of incomplete myotomy is established. A single standard of care should be expected of all surgeons who perform PM for IHPS. 相似文献
189.
Adam E. Gaweda Premila Bhat Gregory A. Maglinte Chun‐Lan Chang Jerrold Hill Grace S. Park Akhtar Ashfaq Matthew Gitlin 《Hemodialysis international. International Symposium on Home Hemodialysis》2014,18(1):38-46
Clinical guidelines recommend concurrent treatment of anemia in end‐stage renal disease with erythropoiesis‐stimulating agents (ESAs) and iron. However, there are mixed data about optimal iron supplementation. To help address this gap, the relationship between iron markers and hemoglobin (Hb) response to ESA (Epoetin alfa) dose was examined. Electronic medical records of 1902 US chronic hemodialysis patients were analyzed over a 12‐month period between June 2009 and June 2010. The analysis included patients who had at least one Hb value during each 4‐week interval for four consecutive intervals (k ? 2, k ? 1, k, and k + 1; k is the index interval), received at least one ESA dose during intervals k ? 1 or k, had at least one transferrin saturation (TSAT) value at interval k, and at least one ferritin value during intervals k ? 2, k ? 1, or k. Effect modification by TSAT and ferritin on Hb response was evaluated using the generalized estimating equations approach. Patients had a mean (standard deviation) age of 62 (15) years; 41% were Caucasian, 34% African American, 65% had hypertension, and 39% diabetes. Transferrin saturation, but not ferritin, had a statistically significant (P < 0.05) modifying effect on Hb response. Maximum Hb response was achieved when TSAT was 34%, with minimal incremental effect beyond these levels. Of the two standard clinical iron markers, TSAT should be used as the primary marker of the modifying effect of iron on Hb response to ESA. Long‐term safety of iron use to improve Hb response to ESA warrants further study. 相似文献
190.
Naureen Akhtar Alexey O. Polyakov Aisha Aqeel Pavlo Gordiichuk Graeme R. Blake Jacob Baas Heinz Amenitsch Andreas Herrmann Petra Rudolf Thomas T. M. Palstra 《Small (Weinheim an der Bergstrasse, Germany)》2014,10(23):4912-4919
Perovskite‐based organic–inorganic hybrids hold great potential as active layers in electronics or optoelectronics or as components of biosensors. However, many of these applications require thin films grown with good control over structure and thickness—a major challenge that needs to be addressed. The work presented here is an effort towards this goal and concerns the layer‐by‐layer deposition at ambient conditions of ferromagnetic organic–inorganic hybrids consisting of alternating CuCl4‐octahedra and organic layers. The Langmuir‐Blodgett technique used to assemble these structures provides intrinsic control over the molecular organization and film thickness down to the molecular level. Magnetic characterization reveals that the coercive field for these thin films is larger than that for solution‐grown layered bulk crystals. The strategy presented here suggests a promising cost effective route to facilitate the excellently controlled growth of sophisticated materials on a wide variety of substrates that have properties relevant for the high density storage media and spintronic devices. 相似文献