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101.
Monoclonal antibodies (MAbs) have been produced against Plasmodium ovale sporozoites and used to characterize the circumsporozoite (CS) protein. Six MAbs were produced, and all were species specific. By using Western blot (immunoblot) analysis, three polypeptides were detected: a predominant 51,000-Mr polypeptide and two presumed precursor 57,000- and 67,000-Mr molecules. The presence of a repeating epitope in the CS protein of P. ovale was demonstrated by using one of the MAbs in a single-antibody two-site enzyme immunoassay. Three MAbs recognized epitopes on the surfaces of sporozoites; the presence of at least one other epitope within the CS protein, but not on the surfaces of P. ovale sporozoites, was also demonstrated.  相似文献   
102.
Lung connective tissue proteins have been assayed in 12 normal juvenile baboons (Papio cynocephalus). The collagen concentration (26.8 +/- 5.1 microgram hydroxyproline per mg dry weight) is comparable to values reported for adult human lung, while the rate of collagen synthesis (0.242 +/- 0.082 nmoles hydroxyproline per mg DNA per hour) is approximately half that of human lung. Proteins other than collagen are synthesized at approximately equal rates in human and baboon lung. Elastin concentration was estimated to be 33 microgram insoluble elastin protein per mg dry weight, within the range reported for normal human lung. Values have also been calculated for the lobar contents of protein, DNA, and collagen, as well as the rates of synthesis of collagen and other proteins in the entire upper lobe of the right lung of these animals. The collagen concentrations in the lung show wide differences among various animal species. However, the baboon lung is similar to human lung. This similarity may be important in the interpretation of alterations in lung connective tissue metabolism associated with experimental diseases.  相似文献   
103.
This large Veterans Administration cooperative study sought to identify the ward milieu characteristics of effective psychiatric programs. It was developed as a multivariable, correlational study that involved systematic observations of program characteristics and outcome effectiveness of wards as they operated in their usual manner. Seventy-nine wards in 18 hospitals provided 11,283 patients eligible for follow-up. Eleven treatment characteristics were found to be correlated to patients' community adjustment 3 months after discharge. These characteristics were classified into five general categories: Patient-staff interaction, patient activities, medication practices, ward physical environment, and nursing staff rotation. The major conclusions are: wards do differ in their effectiveness as measured by ratings of patient posthospital adjustment; and treatment characteristics make a difference in program effectiveness as measured by patients' posthospital adjustment.  相似文献   
104.
Summary Tiazofurin (2--D-ribofuranosylthiazole-4-carboxamide, TCAR) is a synthetic C-nucleoside that demonstrated significant in vivo activity against a variety of animal tumors as well as in vitro activity against human tumor-derived cell lines. Thirteen patients were treated with TCAR administered as a 5-day continuous infusion in this Phase I trial. Seventeen complete cycles were administered in three dose levels ranging from 550 to 1450 mg/M2. Dose-limiting toxicities were myelosuppression and neurotoxicity including severe lethargy. Other toxicities including superficial skin peeling, myalgias, and tearing were seen at all doses. One patient had chest pain on day 4 resulting in stopping the drug, however, there was no evidence of cardiac or pericardial disease. Uric acid levels rose within one day in the absence of allopurinol treatment. There were no treatment related deaths. HPLC measurement of drug levels demonstrated steady-state plasma levels during the infusion, and a half-life following the infusion of 7.7 ± 0.6 hours. Minor abnormalities in renal function were associated with dramatic changes in pharmacokinetics and toxicity. No clinical responses were observed in this trial.Abbreviations TCAR Tiazofurin - HPLC High performance liquid chromatography - IMPD Inosine monophosphate dehydrogenase - WBC white blood cell - CPK creatine phosphokinase - Css steady-state concentration  相似文献   
105.
The development of left ventricular hypertrophy in patients with heart disease often has far-reaching clinical implications with respect to overall morbidity and mortality. Approaches used to assess left ventricular mass include electrocardiography, echocardiography, contrast ventriculography, single photon-emission tomography, and conventional computed tomography. However, all of these modalities suffer from some major draw back that precludes widespread application to all patients. In this study we assessed the accuracy of determinations of left ventricular mass in 22 dogs by rapid-acquisition (50 msec) computed axial tomography (RACAT), an ultrafast computed tomographic (CT) instrument. Electrocardiographically triggered, end-diastolic, short-axis cardiac scans were obtained from apex to base during administration of intravenous iodinated contrast. Myocardial edges were determined for each tomographic scan by two methods: the regional half-contour method (the CT density half way between that of the left ventricular myocardium and adjacent ventricular cavities or lung) and "interactive plateau thresholding" of the cardiac borders. Left ventricular mass by RACAT was calculated as the sum of the mass of each individual scan from apex to base (modified Simpson's rule). Postmortem left ventricular mass ranged from 58 to 160 g. The correlation between true left ventricular mass and tomographically determined mass was excellent (r = .99), with the slope and y intercept not statistically different from 1 and 0, respectively. The standard error of the estimate was 4.1 g. Interobserver and intraobserver variability for determining left ventricular mass demonstrated excellent agreement (r = .99 and r = .99, respectively). We conclude that quantitative assessment of left ventricular mass can be accurately and reproducibly performed in dogs by rapid acquisition CT scanning. It is likely that this technique will be readily transferable to the clinical settings and prove to be an important method for quantifying left ventricular mass in patients.  相似文献   
106.
107.
The development of a technique for studying spinal dorsal horn electrophysiology in intact, awake, drug-free cats enables the study of spinal sites and mechanisms of action of anesthetic and analgesic agents in a system that more closely reflects normal physiology. Using this technique, we reevaluated the effect of ketamine on spinal dorsal horn sensory transmission. The results of our study confirm previous work done in acute preparations. Ketamine (maximum dose 20 mg/kg) did not significantly reduce the response of low threshold (n = 11) dorsal horn neurons to low intensity sensory stimulation. However, that same dose of ketamine did suppress noxiously evoked activity of the two wide dynamic range neurons encountered in the study, while having a varied effect on neurons responsive to proprioceptive input (n = 7). These findings confirm that, in the intact animal with all modulatory systems intact, ketamine "dissociation" of low intensity tactile stimuli does not appear to involve a spinal mechanism of action. The results also support the importance of spinal sites of action for the analgesia produced by ketamine, as well as the importance of distinguishing between the anesthetic and analgesic effects of that drug.  相似文献   
108.
Maternal and Child Health Journal - To ascertain the component of the excess preterm birth (<?37 weeks, PTB) rate among US-born (compared to foreign-born) Black women...  相似文献   
109.
BackgroundStaphylococcus aureus is a major pathogen implicated in orthopedic infections worldwide. Preoperative decolonization has been promoted but different strategies present mixed results. Thus, the goals of this study are to determine (1) whether S aureus screening and/or decolonization is effective at reducing surgical site infection in orthopedic surgery, (2) with a special focus on elective total joint arthroplasty (TJA), and (3) which preoperative S aureus screening/treatment strategy is most cost-effective for TJA.MethodsPubMed, Ovid MEDLINE, and Cochrane databases were searched on January 1, 2020, using a systematic strategy. We included papers with data comparing surgical site infection and periprosthetic joint infection rate in orthopedic surgery and/or elective total hip and knee arthroplasty patients before/after S aureus screening and/or decolonization protocol and papers evaluating the cost-effectiveness of different S aureus screening/treatment strategies.ResultsA total of 1260 papers were screened, and 32 papers were ultimately included. Results showed an increased risk of developing any infection (relative risk [RR] = 1.71 ± 0.16) and S aureus infection (RR = 2.79 ± 0.45) after orthopedic surgery without previous nares and whole-body decolonization. Focusing exclusively on elective TJA, there was an increased risk of developing any infection (RR = 1.70 ± 0.17) and S aureus infection (RR = 2.18 ± 0.41) if no decolonization is performed. All strategies appeared to be cost-effective, although universal decolonization without screening seemed to be the most advantageous.ConclusionPreoperative S aureus screening/decolonization protocol lowered the risk of infection after elective orthopedic and TJA surgeries. However, further studies are needed to determine optimal clinical and cost-effective methodologies.  相似文献   
110.
IntroductionWe sought to determine the impact of payer-mix on post-operative outcomes among Medicare beneficiaries following hepatopancreatic surgery.MethodsMedicare beneficiaries who underwent hepatopancreatic surgery were identified. Hospital quality markers were obtained from the Hospital General Information dataset. Hospitals were dichotomized (low/average vs. high) based on Medicare patient days versus all patient days irrespective of payer type.ResultsHigh Medicare patient-mix hospitals were more likely to be ranked higher than the national average relative to safety of care (29.4% vs. 38.1%) and timeliness of care (15.4% vs. 26.3%) versus low burden Medicare hospitals (both p < 0.001). However, Medicare beneficiaries who had hepatopancreatic surgery at a high Medicare patient-mix hospital were at higher risk of a complication (OR = 1.13, 95%CI 1.04–1.22), and death within 30-days (OR = 1.37, 95%CI 1.23–1.53) following surgery.ConclusionWhile hospitals caring for higher numbers of Medicare beneficiaries generally performed better on CMS quality indicators, these rankings did not equate to improved post-operative outcomes.  相似文献   
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