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681.
Stirling Pillsbury 《The Western journal of medicine》1953,79(5):343-345
In 14,501 deliveries at one hospital there have been no maternal deaths. Several factors have contributed to this eight-year record:1. Immediate availability of blood and liberal use in anemia and in abnormal bleeding has prevented deaths from hemorrhage.2. Antibiotics and early ambulation have reduced infections.3. Spinal anesthetics reduce hemorrhage and allow for greater flexibility in combating complications at delivery.4. Consultations are required for certain complications, are freely available in all cases, and give the advantage of two opinions instead of one.5. Good nursing care is essential. 相似文献
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In 1997, Oregon enacted rules that define an unacceptable population-level risk as a >10% chance of >20% of the total local population receiving an exposure greater than the toxicity reference value. This rule applies to populations of plants and animals not listed as threatened or endangered. An operational procedure was developed to perform such population-level ecological risk assessments. This case study describes how this procedure was used to develop site-specific groundwater remedial action objectives for resident aquatic populations at a site in Northwest Oregon, where an upland petroleum pipeline released gasoline-range hydrocarbons (TPH-G) into soils and groundwater immediately upgradient of the Tualatin River. With an interim response in place, the goal was to proactively establish a remedial action objective that would equate to an acceptable risk level for populations of aquatic receptors potentially threatened by future groundwater discharges to the river. Approximately 10 and 32% dilutions of the water-soluble fraction of pure product produced an acceptable risk level for zooplankton and forage fish populations, respectively. The proposed population-level remedial action objective, based on zooplankton as the most sensitive receptor, was a TPH-G groundwater concentration of 17.4?mg/L. 相似文献
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The Insulin-like Growth Factor (IGF)-I E-Peptides Modulate Cell Entry of the Mature IGF-I Protein
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Lindsay A. Pfeffer Becky K. Brisson Hanqin Lei Elisabeth R. Barton 《Molecular biology of the cell》2009,20(17):3810-3817
Insulin-like growth factor (IGF)-I is a critical protein for cell development and growth. Alternative splicing of the igf1 gene gives rise to multiple isoforms. In rodents, proIGF-IA and proIGF-IB have different carboxy-terminal extensions called the E-peptides (EA and EB) and upon further posttranslational processing, produce the identical mature IGF-I protein. Rodent EB has been reported to have mitogenic and motogenic effects independent of IGF-I. However, effects of EA or EB on mature IGF-I, or whether proIGF-IA and proIGF-IB have different properties, have not been addressed. To determine whether the presence of EA or EB affected the distribution and stability of mature IGF-I protein, transient transfections of cDNAs encoding murine IGF-IA, IGF-IB, and mature IGF-I were performed in C2C12 cells, a skeletal muscle cell line. IGF-I secretion was measured by enzyme-linked immunosorbent assay of the media, and did not differ between expression of proIGF-IA, proIGF-IB, or mature IGF-I expression. Next, epitope-tagged constructs were transfected to determine cellular distribution of IGF-I, EA, and EB in the cells throughout the culture. IGF-I was detected in significantly fewer nontransfected cells in cultures transfected with mature IGF-I compared with transfection of proIGF-IA or proIGF-IB. These results demonstrate that EA and EB are not required for IGF-I secretion but that they increase cell entry of IGF-I from the media. This study provides evidence that the EA and EB may modulate IGF-I in addition to having independent activity. 相似文献
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Lauren A. Harrington Andrew L. Harrington Joelene Hughes David Stirling David W. Macdonald 《European Journal of Wildlife Research》2010,56(3):377-384
Distribution data for elusive species are often based on detection of field signs rather than of the animal itself. However, identifying field signs can be problematic. We present here the results of a survey for American mink, Neovison vison, in the northern highlands of Scotland to demonstrate the importance of verifying field sign identification. Three experienced surveyors located scats, which they identified as mink scats, at seven of 147 sites surveyed and “possible” mink scats at a further 50 sites. Mitochondrial DNA was successfully extracted from 45 of 75 (60%) scats, collected from 31 of the 57 “positive” sites; sequencing of amplified DNA fragments showed that none of these scats was actually of mink origin. We consider the implications of erroneous survey data and the potential waste of resources and misdirection of conservation/management actions. We discuss potential methods that may be useful to verify field sign identification, including the use of DNA analysis, and stress that verification is crucial to ensure rigorous and reliable survey data. 相似文献
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During the breeding season from January to mid-April, adult male Atlantic walruses (Odobenus rosmarus rosmarus) dive repeatedly for an average duration of 4–6 min and give stereotyped underwater vocal displays. Between dives, they surface for 1–2 min, take 4–6 breaths, and give stereotyped vocalizations between breaths. Male walruses vocalize in the presence of groups of females and calves, young adult males, or by themselves as lone singers. This pattern is repeated throughout the breeding season and can be maintained for extended periods, sometimes exceeding 48 h. The prolonged underwater vocal displays of male walruses seem possible because the animals do not exceed the aerobic dive limit (ADL), estimated to be 9.8 min for a 1,100-kg animal, nor do they exceed the behavioral ADL of 7.9 min, determined from the histogram of dives for males singing alone. The number of breaths taken after dives and the postdive surface times remained fairly constant despite dive duration, suggesting that the walruses remained within their aerobic dive limits. The duration of most dives made by displaying males vocalizing alone during the breeding season, and dive duration of walruses feeding for protracted periods outside the breeding season, are both roughly half the estimated ADL. 相似文献