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41.
Cardiovascular resuscitation of the severely injured patient in the field remains unsatisfactory because large volumes of intravenous fluid are needed to keep up with ongoing blood losses and because only small volumes of fluid can be given. In the first study reported here, small volumes (less than or equal to 12 mL/kg) of 3% NaCl were given to patients who were having surgery for severe injuries. The 3% NaCl restored blood pressure, pH, and urine output with approximately one half of the cumulative fluid requirement of patients who received isotonic fluids (p less than 0.05). In a second study, 7.5% NaCl/dextran 70, 250 mL, was given in a prospective, randomized, and double-blinded trial to injured patients in the field. Blood pressure in the hypertonic/hyperoncotic group increased 49 mmHg during transport (p less than 0.005); blood pressure in patients given lactated Ringer's solution increased 19 mmHg (NS). Survival favored the hypertonic/hyperoncotic group. The 7.5% NaCl/dextran 70 solution appears particularly promising for treatment of injured patients in the field.  相似文献   
42.
Background: Erythrocytes are transfused to improve oxygen delivery and prevent or treat inadequate oxygenation of tissues. Acute isovolemic anemia subtly slows human data processing and degrades memory, increases heart rate, and decreases self-assessed energy level. Erythrocyte transfusion is efficacious in reversing these effects of acute anemia. We tested the hypothesis that increasing arterial oxygen pressure (Pao2) to 350 mmHg or greater would supply sufficient oxygen to be equivalent to augmenting hemoglobin concentration by 2-3 g/dl and thus reverse the effects of acute anemia.

Methods: Thirty-one healthy volunteers, aged 28 +/- 4 yr (mean +/- SD), were tested with verbal memory and standard, computerized neuropsychologic tests before and twice after acute isovolemic reduction of their hemoglobin concentration to 5.7 +/- 0.3 g/dl. Two sets of tests were performed in randomized order at the lower hemoglobin concentration: with the volunteer breathing room air or oxygen. The subject and those administering the tests and recording the results were unaware which gas was administered. As an additional control for duration of the experiment, 10 of these volunteers also completed the same tests on a separate day, without alteration of hemoglobin concentration, at times of the day similar to those on the experimental day. Heart rate, mean arterial blood pressure, and self-assessed sense of energy were recorded at the time of each test.

Results: Reaction time for digit-symbol substitution test increased, delayed memory was degraded, mean arterial pressure and energy level decreased, and heart rate increased at a hemoglobin concentration of 5.7 g/dl (all P < 0.05). Increasing Pao2 to 406 +/- 47 mmHg reversed the digit-symbol substitution test result and the delayed memory changes to values not different from those at the baseline hemoglobin concentration of 12.7 +/- 1.0 g/dl, and decreased heart rate (P < 0.05). However, mean arterial pressure and energy level changes were not altered with increased Pao2 during acute anemia.  相似文献   

43.
Depression is under-detected, but is treatable and relapses can be prevented. Living with depression, whether acute or chronic, has consequences for quality of life, premature end of life, and productive life. Thoughtful and strategic quality improvement (QI) programs offer one avenue for improving the treatment of depression. Part I of this two-part series addresses improving the treatment of depression and employing disease management as a strategy to accomplish that aim. This article, part II, provides an overview of other QI initiatives that demonstrated treatment effectiveness for depression, including several used in managed care practice.Currently, the majority of QI programs for depression target adult patients; therefore, there are future challenges ahead as managed care attempts to address the needs of special populations, such as adolescents and older adults. Public education, professional education, and population-based interventions are also considerations as part of successful treatment. Although consumer-based interventions are typically more expensive, they may ultimately yield the best results for improving depression care for the consumer and payors based on available research. The success of a consumer-centric approach is highly reliant on the person’s engagement with QI programs, the treating clinician’s appreciation and support of such depression programs, and managed care’s response to solving quality problems using continuous monitoring, evaluation, feedback, system enhancements, and training. Models of collaboration between consumers and medical and behavioral health systems offer the most promising approaches to care improvements for patients with depression.  相似文献   
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A technique for undiverting a colonic conduit of limited capacity and with short ureters is described. The colonic segment of the conduit and an additional segment of small bowel are patched together to form a low pressure cystoplasty of large capacity. This technique incorporates 3 principles that are believed to be important in reconstructing any type of cystoplasty: large capacity, increase in diameter and disruption of the strong circular muscle layer of the bowel by detubularization.  相似文献   
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47.
Class I major histocompatibility complex (MHC) cDNA clones have been isolated from an expression library derived from mRNA of an MHC homozygous Xenopus laevis. The nucleotide and predicted amino acid sequences show definite similarity to MHC class I molecules of higher vertebrates. The immunoglobulin-like alpha-3 domain is more similar to the immunoglobulin-like domains of mammalian class II beta chains than to those of mammalian class I molecules, and a tree based on nucleotide sequences of representative MHC genes is presented.  相似文献   
48.
BACKGROUND: Frequent infection in infancy and early childhood has been hypothesized to explain the low prevalence of asthma and other atopic disease among children in developing countries (the so-called 'hygiene hypothesis'), but the low prevalence in Eastern Europe remains unexplained. OBJECTIVE: To test the hygiene hypothesis in the Republic of Belarus by examining the relationship between gastrointestinal (GI) and respiratory infection and two potentially atopic outcomes in the first 12 months of life: atopic eczema and recurrent wheeze. METHODS; We carried out two case-control studies nested within a large (n=17 046) randomized trial in Belarus, with cases defined as (1) first occurrence of atopic eczema (n=819) and (2) second episode of wheezing (n=112). Incidence density sampling was used to select four matched controls born within 1 month at the same hospital as the case. Exposure was defined as one or more episodes of GI or respiratory infection (examined separately) with onset >7 days before onset of the case's atopic outcome. Analyses controlled for family atopic history, duration of exclusive breastfeeding, sex, birth weight, maternal education, and (for recurrent wheeze) maternal smoking. RESULTS: For atopic eczema, prior GI infection occurred in 7.4% of cases vs. 6.0% of controls [adjusted OR=1.27 (0.94-1.72)] and prior respiratory infection in 35.2% vs. 32.6% [adjusted OR=1.14 (95% CI=0.94-1.37)]. For recurrent wheeze, prior GI infection occurred in 9.8% of cases vs. 7.4% of controls [adjusted OR=1.30 (0.60-2.82)]. CONCLUSION: Our results do not support the hypothesis that infection protects against atopic eczema or recurrent wheezing in the first 12 months of life.  相似文献   
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50.
E B Heald  S T Kramer  J P Smith 《Pancreas》1992,7(5):530-535
The effect of unsulfated cholecystokinin on pancreatic growth was evaluated in two experimental models in vivo and in vitro. Mice were injected with sulfated cholecystokinin (CCKs) or unsulfated cholecystokinin (CCKu) (10 or 20 micrograms/kg) or vehicle twice daily for 15 days. Animals were then killed and pancreatic weights, protein, amylase, and DNA content were evaluated. In vitro, growth was evaluated by DNA synthesis and viable cell counts. MIA PaCa-2 and BxPC-3 human pancreatic cancer cells were treated with CCKs or CCKu (10(-12) to 10(-9) M) for 48 or 72 h in the presence of [3H]thymidine to evaluate DNA synthesis. Viable cell counts were performed on both cell lines grown in the presence or absence of unsulfated CCK (10(-12) to 10(-9) M) for 96 h. Pancreatic weight, protein, amylase, and DNA were significantly increased in animals treated with either CCKs or CCKu. However, pancreatic weight, protein, and amylase were significantly higher in mice treated with CCKs compared to CCKu (p less than 0.005). DNA content and index of hyperplasia were the same whether mice were treated with CCKs or CCKu. CCKu was as potent a stimulus for DNA synthesis as CCKs in MIA PaCa-2 and BxPC-3 cells. Finally, CCKu increased cell counts in both pancreatic cancer cell lines. These data suggest that the mechanisms responsible for CCK-induced growth of normal pancreas and pancreatic cancer may differ from those that regulate secretion.  相似文献   
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