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41.
The purposes of this study were to determine the effects of positive end-expiratory pressure (PEEP) and end-expiratory lung volume on systemic blood flow, whether PEEP levels yielding maximum systemic oxygen transport are associated with maximum lung compliance, and the effects of end-expiratory lung volume on pulmonary resistance to gas flow, in an animal model of respiratory distress. Twelve cats were inoculated with 12 mg/kg N-Nitroso N-Methylurethane (NNNMU) to induce respiratory distress. The NNNMU caused a 76% decrease in disaturated phosphatidyl-choline of lung lavage, a 34% decrease in functional residual capacity (FRC), an 80% decrease in lung compliance, an 88% increase in pulmonary resistance to gas flow, a 43% decrease in PaO2, and a 37% decrease in oxygen consumption. Systemic blood flow and systemic oxygen transport were not significantly altered by the chemically induced respiratory distress. PEEP levels of 5.1 +/- 0.8 cm H2O returned end-expiratory lung volume to normal FRC levels. Increases in PEEP caused systemic blood flow to decrease even when end-expiratory lung volume was below or equal to normal FRC levels but did not significantly affect systemic oxygen transport, lung compliance, or pulmonary resistance. We conclude that in cats with NNNMU-induced respiratory distress: PEEP causes decreases in systemic blood flow, lung compliance and systemic oxygen transport are not clear indicators of optimal PEEP level, and returning end-expiratory lung volume to normal FRC does not significantly reduce pulmonary resistance to gas flow.  相似文献   
42.
Ganesan  TS; Min  GL; Goldman  JM; Young  BD 《Blood》1987,70(3):873-876
Four patients with Philadelphia (Ph') positive chronic myeloid leukemia (CML) were studied before, after, and on relapse following allogeneic bone marrow transplantation (BMT). Southern analysis of DNA from cells collected before and at relapse after BMT was performed in order to investigate the origin of the leukemia at relapse. Using minisatellite probes we showed that the relapse occurred in cells of host origin in all four patients and this was confirmed with a Y chromosome specific probe in two male patients who had a female donor. Furthermore, using two probes for the breakpoint cluster region (bcr) on chromosome 22, we showed that leukemic cells at relapse bore identical rearrangements to those in the disease at time of presentation of each patient. We conclude that relapse in all four patients is due to re-emergence of the original leukemic clone.  相似文献   
43.
Background: The feasibility of accessing data in hospitalized patients to support a malnutrition diagnosis using the new Academy of Nutrition and Dietetics–American Society for Parenteral and Enteral Nutrition (AND‐A.S.P.E.N.) consensus recommended clinical characteristics of malnutrition is largely unknown. We sought to characterize baseline practice to guide the development of appropriate interventions for implementation of the recommended approach. Materials and Methods: A cross‐sectional survey was conducted of 262 consecutive adults who were referred for dietitian or nutrition support team assessments at 2 tertiary teaching hospitals in Pennsylvania. The availability of data to support the proposed AND‐A.S.P.E.N. approach and the resulting malnutrition diagnoses were examined. Results: Mean ± SD age was 58.2 ± 17.1 years, and half were female. Food intake history was available for 76%, weight history for 67%, and physical examination for loss of fat and muscle mass for 94% and for edema for 84%. Hand‐grip strength was not available. The prevalence of malnutrition among the patients referred for nutrition assessment was 6.7% moderate, 7.6% severe with acute illness; 12.2% moderate, 11% severe with chronic illness; and 0.8% moderate, 0.4% severe with social circumstances. Decline in typical food intake and weight loss were the most commonly used clinical characteristics. Conclusion: Data could generally be accessed to support the AND‐A.S.P.E.N. consensus clinical characteristics for malnutrition diagnosis, but further testing in multiple care settings is needed before these observations may be generalized. Training in assessment methods and dissemination of the necessary tools will be necessary for full implementation.  相似文献   
44.

Objective

To explore the clinical effect of the tuberculosis (TB) doctor–nurse integration management model

Methods

This study is a retrospective historical cohort study. The clinical data of 180 patients with TB in our hospital from 2019 to 2020 were analyzed retrospectively. In a control group, 90 cases were treated with the traditional medical care model. An observation group of 90 cases received clinical diagnoses, treatments, and nursing under a doctor–nurse integration management model. Comparative analyses between the two groups were conducted on various aspects, including the awareness level of TB prevention and control, medication compliance and patient satisfaction. Comparisons between the two groups were evaluated using independent-sample t-tests or Chi-squared tests

Results

Compared with the control group, the knowledge awareness levels of TB prevention and medication compliance in the observation group were significantly higher (p < .05). The appointment waiting times and hospitalization times in the observation group were significantly lower than in the control group (p < .05). The total average satisfaction score of the patients in the observation group was significantly higher than in the control group (p < .05). Compared with the control group, the patients in the observation group were significantly more satisfied with their nursing methods, operating techniques, psychological techniques, service attitudes, and ward management (p < .05). In addition, in the observation group, medical–nursing relationships and doctor–patient communication were better than in the control group; additionally, the satisfaction of doctors with nursing work was also higher than in the control group, which was a statistically significant difference (p < .05)

Conclusion

The implementation of an integrated medical–nursing cooperation model for TB will help increase the awareness of health knowledge in patients with TB, improve patient medication compliance and enhance patient satisfaction.  相似文献   
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The goal of targeted imaging is to produce an enhanced view of physiological processes or pathological tissue components. Contrast agents may improve the specificity of imaging modalities through selective targeting, and this may be particularly significant when using ultrasound (US) to image inflammatory processes or thrombi. One means of selective targeting involves the attachment of contrast agents to the desired site with the use of a specific binding mechanism. Because molecular binding mechanisms are effective over distances on the order of nanometers, targeting effectiveness would be greatly increased if the agent is initially concentrated in a particular region, and if the velocity of the agent is decreased as it passes the potential binding site. Ultrasonic transmission produces a primary radiation force that can manipulate microbubbles with each acoustic pulse. Observations demonstrate that primary radiation force can displace US contrast agents from the center of the streamline to the wall of a 200-microm cellulose vessel in vitro. Here, the effects of radiation force on contrast agents in vivo are presented for the first time. Experimental results demonstrate that radiation force can displace a contrast agent to the wall of a 50-microm blood vessel in the mouse cremaster muscle, can significantly reduce the velocity of flowing contrast agents, and can produce a reversible aggregation. Acoustic radiation force presents a means to localize and concentrate contrast agents near a vessel wall, which may assist the delivery of targeted agents.  相似文献   
49.
This study sought to determine if Whites and African-Americans respond similarly to headache treatment administered in 'real-world' headache specialty treatment clinics. Using a naturalistic, longitudinal design, 284 patients receiving treatment for headache disorders completed 30-day daily diaries that assessed headache frequency and severity at pretreatment and 6-month follow-up and also provided data on their headache disability and quality of life at pretreatment and 1-, 2- and 6-month follow-up. Controlling for socioeconomic status and psychiatric comorbidity, hierarchical linear models found that African-Americans and Whites reported significant reductions in headache frequency and disability and improvements in life quality over the 6-month treatment period. African-Americans, unlike Whites, also reported significant decreases in headache severity. Nevertheless, Africans-Americans had significantly more frequent and disabling headaches and lower quality of life after treatment relative to Whites. Although Whites and African Americans responded favourably to headache treatments, more efficacious treatments are needed given the elevated level of headache frequency that remained in both racial groups following treatment.  相似文献   
50.
Objective: To investigate the safety and pharmacokinetics of bromotetrandrine (BrTet, W198), a novel inhibitor of P‐glycoprotein (P‐gp), after single‐dose i.v. infusion in healthy Chinese volunteers. Methods: We conducted a randomized, dose‐escalating, phase I clinical study for that purpose. Thirty healthy subjects received BrTet at the doses of 10, 20 or 30 mg/m2 by i.v. infusion. Plasma and urine concentrations of bromotetrandrine were determined by using a liquid chromatography–tandem mass spectrometric (LC/MS/MS) method. AUC was calculated by the trapezoidal rule extrapolation method. Cmax, Tmax, t1/2α, t1/2β, Cl and Vd were compiled from the plasma concentration–time data. Results: Bromotetrandrine was generally well tolerated at all doses. No serious or severe adverse events were found in the study. The pharmacokinetic parameters of BrTet after single i.v. infusion doses of BrTet 10, 20 and 30 mg/m2 were as follows: Tmax were 1·5 h in three groups, Cmax were 24·79, 39·59 and 64·31 μg/L, t1/2α were 0·37, 0·29 and 0·30 h, t1/2β were 62·88, 56·45 and 52·20 h. AUC0–194h were 345·83, 688·15 and 1096·28 μg h/L, Cl were 23·68, 25·69 and 25·66 L h/m2, Vd were 157·73,156·96 and 140·73 L/m2. In urine, the total eliminate rate of originate compound was 0·61 ± 0·19%. Conclusions: This study suggested that bromotetrandrine was well tolerated in healthy volunteers within the dose range evaluated. The pharmacokinetics parameters of bromotetrandrine indicated that the compound was rapidly distributed and accumulated in the tissues, and slowly cleared from plasma, which supported the use of BrTet for a once or twice dosing per chemotherapy cycle.  相似文献   
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