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91.
Postinjury abdominal compartment syndrome (ACS) has evolved during the 1980s together with the introduction of damage control surgery (DCS) principles. DCS made it possible to salvage severely injured trauma patients who previously would have exsanguinated due to uncontrollable coagulopathic bleeding. These patients had severe hemorrhagic shock; their abdomens were tightly packed and had ongoing massive resuscitation. ACS is a lethal complication of the damage control patients. For today the pathophysiological characteristics of ACS are described, the intra-abdominal pressure is measured on many intensive care units. Postinjury ACS (primary and secondary) is one of the better characterized etiological types of ACS: risk factors, diagnostic criteria, independent predictors and preventive strategies are all well documented. Since the mortality of full-blown postinjury ACS is still unacceptably high and does not seem to improve with earlier decompression, prevention is the recommended strategy to decrease the morbidity and mortality. Open abdomen is one of the important preventive strategies but it is not free from morbidity and mortality. With aggressive open abdomen management in postinjury ACS these complications can be minimized. More importantly, timely hemorrhage control and hemostatic resuscitation are the likely solutions for more efficient prevention of the postinjury ACS.  相似文献   
92.
The Personal Development Study (PDS) was administered to four diagnostic groups, which included 89 hospitalized alcoholics, 336 unmarried mothers, 159 college students, and 387 chronic institutionalized schizophrenics. The PDS data from the four groups were factor analyzed separately by Varimax rotation of principal component factors. Cluster analysis methods were used to compare the separate diagnostic group factors with the overall factors previously reported by Pishkin and Thorne (1977). Only a few close fits of the diagnostic group factors showed large differences in item composition, order of emergence of factors and size of loadings between groups. Because many items and factors could be interpreted in terms of several alternative theoretical systems, interpretations were based on the clinical meanings of items and clusters in terms of integration theory (Thorne, 1976).  相似文献   
93.
Factorial findings on the Personal Development Study (PDS) were reported in an overall population of 972 Ss in four diagnostic subgroups. The general results indicate that several mechanisms were extracted factorially. Five overall factors were identified, but their item contents and meanings were not identical with the postulated empirical factors. Large subgroup variability occurred in the nature of factors identified, in the order of factor appearance, in the size of item loadings, and in the clinical meanings of item clusters. One conclusion is that the factorial structure of psychological states is very complex and changes constantly under different conditions and situations.  相似文献   
94.
Citation indices potentially are very invalid because they are susceptible to manipulations and irrelevant weightings when utilized as indices of merit. The whole process of citing references is very idiosyncratic and a reflection of author biases because references can be cited on either side of any contention. On the basis of more than 30 years of editorial experience, a listing is made of ways in which eitation indices can be manipulated by factors irrelevant to merit. Genuine merit can be assessed only by long-term validity and predictive usefulness after many replications by independent studies.  相似文献   
95.
The effect of sepsis on plasma levels of various gut peptides was studied in rats. Sepsis was induced by cecal ligation and puncture (CLP); control animals underwent sham operation. Sixteen hours after CLP or sham operation, portal and systemic blood was drawn, and plasma levels of gastrin, vasoactive intestinal peptide (VIP), secretin, peptide YY (PYY), gastrin-releasing peptide (GRP), and substance P were determined by radioimmunoassay. Plasma levels of gastrin, VIP, PYY, and secretin were elevated in septic rats compared with nonseptic animals, with the highest levels noted in portal blood. There was no effect of sepsis on GRP or substance P levels. In other experiments, human recombinant interleukin 1 alpha (IL-1 alpha) or recombinant tumor necrosis factor alpha (TNF alpha) was injected intraperitoneally (300 micrograms/kg body weight in 3 divided doses over 16 hours). There was no change in plasma levels of gut peptides after IL-1 alpha injection. TNF alpha induced elevation of PYY levels in portal plasma with no change in other gut peptide levels. The results suggest that sepsis stimulates release of certain gut peptides and that TNF, but not IL-1, may be partly responsible for this response. The mechanism of the release of gut peptides and its significance in the pathophysiologic changes induced by sepsis remain to be determined.  相似文献   
96.
BACKGROUND: Near-infrared spectroscopy (NIRS) can continuously and noninvasively monitor tissue oxygen saturation (StO2) in muscle and may be an indicator of shock severity. Our purpose was to evaluate how well StO2 predicted outcome in high-risk torso trauma patients presenting in shock. METHODS: The primary outcome in this prospective study was multiple organ dysfunction syndrome (MODS). StO2 data were obtained upon hospital arrival and for 24 hours along with other known predictors of hypoperfusion and clinical outcomes. Clinicians were blinded to StO2 measurements. RESULTS: Seven Level I trauma centers enrolled 383 patients, 50 of whom developed MODS. Minimum StO2 performed similarly to maximum base deficit (BD) in discrimination of MODS patients. The sensitivity for both measures (StO2 cutoff = 75%; BD cutoff = 6 mEq/L) was 78%, the specificity was 34% to 39%, the positive predictive value was 18% to 20% and the negative predictive value was 88% to 91%. StO2 and BD were also comparable in predicting death. CONCLUSIONS: NIRS-derived muscle StO2 measurements perform similarly to BD in identifying poor perfusion and predicting the development of MODS or death after severe torso trauma, yet have the additional advantages of being continuous and noninvasive.  相似文献   
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98.

Considered in this paper is a broad range of evidence bearing on the calcium absorption hypothesis that has been advanced to explain high frequencies of the gene for persistence of lactase activity (PLA) among adults in northern Europe. According to that hypothesis, lactase‐sufficient individuals in early northern Europe enjoyed a selective advantage over lactase‐deficient ones that led to high incidences of PLA in adults of the region. Northern Europeans, the hypothesis goes, suffered from a dietary shortage of vitamin D and, in addition, were unable to synthesize adequate vitamin D from the sun's ultraviolet radiation because of northern Europe's cloudiness and its location in higher latitudes. This led to chronic vitamin D deficiency along with a reduced ability to absorb calcium from milk and lactose‐rich dairy products. As a result, the deficiency diseases rickets—which affects infants and children and can leave a child with bowlegs and other bone defects—and osteomalacia—which weakens and deforms the bones of adults—were common in early northern Europe, and represented powerful selective forces that contributed to development of the highly depigmented skin that is typical of the region's peoples. In addition, the hypothesis goes, calcium absorption was enhanced by a process independent of vitamin D. Such enhancement, found especially or solely among lactase‐sufficient individuals, was brought on by ingestion of lactose in milk and milk products. Thus, persons who enjoyed high lactase activity through life were favored in the struggle for survival, which ultimately led northern European peoples to have among the highest incidences of PLA in the world.

In this article, evidence, much of it recent, is presented to show that lactase‐deficient humans are able to absorb calcium from milk as readily, or nearly as readily, as lactase‐sufficient humans. Evidence is also presented that rickets and osteomalacia occur in parts of the world that have an abundance of sunshine, whether originating from customs that limit exposure to sunshine or otherwise; that heavy cloud cover and high latitude need not result in vitamin D deficiency, rickets, and osteomalacia; that, indeed, osteological evidence from archeological sites in northern Europe indicates that rickets and osteomalacia were quite rare in antiquity; that those conditions appear to have become common in northern Europe only with the advent of the Industrial Revolution, too short a time to have been a significant factor in bringing on the high incidences of PLA that prevail today; and that, indeed, the calcium absorption hypothesis is not confirmed by historical, osteoarcheological, or bio‐medical evidence.  相似文献   
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