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81.
This study was devised to identify sepsis-relevant parameters that early and reliably predict a lethal outcome in intra-abdominal sepsis. In 18 Duroc pigs, peritonitis was induced through standardized gastrotomy. Twelve hours later the defect was oversewn and the abdominal cavity lavaged thoroughly. Sepsis relevant parameters were measured before initiating therapy, and 30 min later animals were extubated and observed for a period of 6 days under adequate analgesia with free access to water and food. All parameters were correlated with survival postoperatively. In the treatment group, 7 out of 18 pigs (39%) died within the observation period. Endotoxin level at 30 min after initiation of therapy [17.9 EU/mL (+/- 12.1) vs. 110.9 EU/mL (+/- 21); p <.001] and Delta pHi [0.015 (+/- 0.011) vs. -0.039 (+/- 0.013); p =.016] were identified as the two parameters with highest predictive power regarding mortality in a multivariate analysis. In conclusion measurement of endotoxin and gastric tonometry should gain wider clinical application in septic patients.  相似文献   
82.
Zusammenfassung. Mit dem Ziel, die Incidenz tiefer Venenthrombosen bei selektierten Patienten nach laparoskopischer Cholecystektomie und anderen minimal-invasiven chirurgischen Eingriffen zu bestimmen, sowie die Sicherheit und Wirksamkeit eines niedermolekularen Heparinpr?parats (NMH) in der postoperativen Thromboseprophylaxe zu belegen, wurde eine prospektive, randomisierte, kontrollierte klinische Studie durchgeführt. Dabei wurden 718 Patienten nach Randomplan einer von 2 Prüfgruppen zugeordnet: Eine Gruppe erhielt physikalische Ma?nahmen zur Thromboseprophylaxe, wie Kompressionsstrümpfe mit graduiertem Andruck (n = 359), die 2. Gruppe erhielt ebenfalls physikalische Ma?nahmen und zus?tzlich ein NMH (Reviparin-Natrium, Clivarin) s. c. einmal t?glich (n = 359). Aus Sicherheitsgründen mit Hinblick auf die medikament?s unbehandelte Kontrollgruppe wurden Patienten mit 3 oder mehr Risikofaktoren für eine ven?se Thromboembolie nicht in die Studie aufgenommen. Die Diagnostik tiefer Beinvenenthrombosen erfolgte mittels Duplexscan. In dieser, eher künstlichen Niedrigrisikoselektion war die Gesamtincidenz thromboembolischer Ereignisse überraschend gering: 5 Verdachtsf?lle einer Lungenembolie, von denen nur 1 Lungenembolie szintigraphisch verifiziert werden konnte, sowie eine phlebographisch best?tigte Unterschenkelthrombose. Die Anwendung von Reviparin zur Prophylaxe ven?ser Thromboembolien war sicher und anwenderfreundlich – die Incidenz postoperativer Blutungskomplikationen betrug nur 2,3 % in der NMH-Gruppe und war somit sogar geringfügig niedriger als in der Kontrollgruppe (3,2 %). Die tats?chliche Incidenz tiefer Venenthrombosen bei Patienten nach laparoskopischer Cholecystektomie bleibt jedoch nach wie vor unklar. Weitere klinische Studien müssen in einem unselektierten Patientengut durchgeführt werden.   相似文献   
83.
Sporozoites and free circumsporozoite (CS) protein were stained immunoenzymatically in 1-min saliva samples collected fromAnopheles stephensi mosquitoes infected with eitherPlasmodium berghei orP. falciparum. The number of sporozoites in 1-min saliva-streak samples significantly increased as the salivary gland index rose from 3+ to 4+. ForP. berghei-infected mosquitoes from which saliva had been collected before 30 days postfeed, the median sporozoite counts for 3+ and 4+ gland indexes were 4.5 and 116, respectively. ForP. falciparum-infected mosquitoes, the median counts obtained in two experiments were 4.5 and 14.5 (3+) and 97 and 107 (4+), respectively. The frequency of sporozoite detection in the saliva of mosquitoes containing <100 salivary-gland sporozoites was low (0.1), whereas that in the saliva of mosquitoes with >100 sporozoites was high (0.96). In highly infected 4+P. berghei-infected mosquitoes from which saliva had been collected after 30 days postinfection, both the volume of saliva collected and the median number of sporozoites recovered decreased significantly.  相似文献   
84.
African Americans experienced massive internal migrations that shifted more than 6 million Southern-born blacks to other sections of the United States over the past century, a trend that only recently has been reversed. Whenever mass migration takes place, there is an opportunity to examine the role of the native and relocated environments in the development of disease. This article examines those relationships for diabetes mellitus, a group of diseases that disproportionately affect African-Americans relative to other racial and ethnic groups in the United States. Age-specific and age-adjusted rates with 95% confidence intervals were calculated for males and females for combinations of five regions of birth and four regions of residence at time of death. Southern-born males had statistically significantly higher death rates from diabetes than did their counterparts who died in the same regions in 9 of 16 comparisons. For females, those born in the South had statistically significantly higher rates in 15 of 16 comparisons. The results of this study indicate that place of birth and early life experiences are statistically associated with diabetes mortality among African Americans regardless of place of residence at time of death.  相似文献   
85.
Routine clinical use of radiographic contrast media (RCM) causes adverse reactions in some patients. To elucidate the mechanisms of these reactions both in vitro and in vivo studies are necessary. In this study, RCM-induced histamine release from isolated mast cells was compared with the in vivo release of histamine and cardiovascular symptoms using a porcine model. The 2 non-ionic preparations examined (Solutrast and Ultravist) released little or no histamine from the 4 cell types tested (porcine pulmonary, cardiac, hepatic, and renal mast cells). The 4 ionic preparations (Angiographin, Hexabrix Rayvist, and Telebrix) caused histamine release from most of the cell suspensions. In almost all cases, the cardiac mast cells were the most sensitive followed by the hepatic mast cells. All 4 RCM tested in vivo produced elevated plasma histamine levels in some animals. The highest incidence was observed using the ionic, high osmolal Rayvist (6 of 12 animals), followed by the non-ionic RCM with the lowest osmolality Ultravist (4 of 12 animals). In vivo, mechanisms in addition to direct histamine release may also be involved in RCM-induced adverse reactions, since low osmolal, non-ionic RCM can cause elevated plasma histamine levels without in vitro release. The susceptibility of cardiac mast cells to RCM-induced histamine release suggests that patients undergoing e.g. coronary angiography may be especially at risk for an adverse reaction.  相似文献   
86.
In spite of significant advances in the past decade, assessing of severe prognosis in acute pancreatitis remains an improvable problem. Actually the standardized means are clinical, multiple laboratory and peritoneal lavage. In a series of 20 subsequent cases of acute pancreatitis with a lethality of 30%, apolipoprotein AII has proven to be a predictor of fatal outcome with a sensitivity in the range of all other methods together. Competitive replacement of Apo AII by serum amyloid like substance A as an indicator for the amount of necrosis would explain this relation. Whether this suggestion can be confirmed by ongoing work or not, apolipoprotein AII merits attention in this context.  相似文献   
87.
88.
I contend that although the Luborsky et al. findings on the Dodo bird verdict are noteworthy, the methodology on which they are based is significantly delimited. Amplifying Luborsky et al.'s moderate recognition of that delimitation, I propose a qualitative complement to the extant research. I call this complement "amalgamated" qualitative research and propose that it will deepen, clarify, and contextualize Luborsky et al.'s enigmatic findings. Until this amalgam is implemented, therapy research will be relegated to impressions rather than fine-grained illuminations.  相似文献   
89.
In a retrospective study, 1.173 fractures of the proximal femur, which had been treated surgically, were analysed in two periods from 1975 to 1991 and from 1992 to 2000. The influence on mortality of preoperative risk factors and primary treatment with total hip replacement (THR), even in cases of pertrochanteric fractures, was analysed by stepwise logistic regression. In the later period, mortality within 90 days was 13.1%, and within 1 year 22.2%. Rejection of hemiendoprosthesis in high-risk patients with intracapsular fractures increased the mortality rate from 6.3% to 11.8%. The introduction of dynamic hip screws instead of Ender nails led to a reduction of mortality from 16.5 to 7.1%. Higher mortality after THR (27.6%) compared to osteosynthesis (15.5%) in pertrochanteric femur and lateral neck fractures was due to higher age and increased risk factors. Although the influence of some risk factors could be reduced, age, sex and morbidity influenced the outcome more than surgical treatment. THP, even after pertrochanteric fractures, is reasonable if it guarantees a quick and enduring mobilisation of the patient. Bicentric bipolar prostheses are recommended for high risk patients.  相似文献   
90.
GM1 ganglioside is believed to be important in promoting the recovery of neurons from injury. The present study assesses the ability of GM1 to repair or prevent the damage of dopamine neurons caused by the neurotoxin 1-methyl-4-phenylpyridinium (MPP+). Treatment of mesencephalic cell cultures with 2.5 μM MPP+ resulted in the loss of 30% of tyrosine hydoxylase (TH) immunoreactive neurons. In contrast, cultures administered 100 μM GM1 ganglioside for 3 days after toxin treatment contained nearly control numbers of TH+ neurons (97%). This reparative effect of GM1 was reflected in parallel increases in TH enzyme activity, dopamine and dopac levels. Cultures sustaining greater insult from higher doses of MPP+ (5.0–10.0 μM) did not benefit from ganglioside treatment, suggesting that rescue by GM1 depended on the degree of initial damage to cells. Moreover, the timing of ganglioside treatment was critical; pretreatment with GM1 alone did not prevent or attenuate the damage caused by subsequent incubation in 2.5 μM MPP+.  相似文献   
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