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101.
Although thoracoabdominal injuries are uncommon in the athlete, they can be catastrophic if unrecognized or if diagnosis and treatment are delayed. This article reviews thoracic, intrathoracic, abdominal, and groin injuries in the athlete, and how they can be diagnosed and managed.  相似文献   
102.
Immunisation practices were examined at 6 hospitals in the western Cape during the latter half of 1992 to determine whether these practices had improved subsequent to the February 1991 resolution of the Health Matters Committee (HMC) on immunisation in hospitals, and since a similar study was undertaken in 1990. Exit interviews were conducted with the escorts of all children aged 3-59 months who attended the study hospitals on the days designated for the study. In the second study, 88 of the 311 children studied (28.3%) were in need of immunisation on arrival, but only 12 of the 88 (13.6%) were immunised during the hospital visit. There was no evidence of an increase in requests to see children's Road-to-Health cards (37.1% compared with 35.2% previously). The incidence of missed opportunities for measles immunisation in children aged 6-59 months remained unacceptably high (51.4% compared with 63.7% previously, when a strict definition was used; and 15.7% compared with 18.1% previously, when a lenient definition was used). Health authorities at all levels need to take urgent action to address the problem of missed opportunities for immunisation at hospitals.  相似文献   
103.
The mature B cell repertoire in the course of murine AIDS (MAIDS) was investigated. The polymerase chain reaction (PCR) was used to amplify a large diversity of rearranged Ig H chain genes in normal or infected mice, 2 and 8 wk after virus inoculation. Libraries were constructed from the polymerase chain reaction products. By sequencing V-D-J clones in these libraries and analyzing the respective complementary determining region 3 (CDR3), we have shown at 8 wk the emergence of a population of B cells with significantly less N diversity, some sequences lacking any N addition, a typical feature of fetal repertoires known for degeneracy, and autoreactivities. This decreased N diversity was not present 2 wk after inoculation and could not be related to a defect in terminal deoxytransferase expression because the steady-state levels of terminal deoxytransferase mRNA were found normal in MAIDS bone marrow 8 wk after inoculation. FACS analyses revealed a decreased number of bone marrow B cells (B220+, sIgM+) in MAIDS already present at 2 wk, suggesting an alteration in the pathway of B cell differentiation and resulting in a decrease of peripheral B cells renewal. A relative enrichment of spleen cells in long lived B cells as a consequence of this blockade may participate in the abnormal antibody repertoire selection occurring in MAIDS. These data suggest in the MAIDS pathogeny the relationship between an abnormal repertoire selection and the pathologic process.  相似文献   
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BACKGROUND: Hypertension and hypercholesterolemia are frequently associated with this leading to considerable cardiovascular risk. METHODS: An open parallel randomized study was performed in which the effects of doxazosin, an alpha-adrenergic blocker and enalapril, an inhibitor of the angiotensin converting enzyme were compared in 70 patients with essential high blood pressure and plasma cholesterol levels greater than 240 mg/dl. Following 2-4 weeks of placebo administration the patients were randomly treated with one of the two drugs. When required doses were increased and hydrochlorothiazide added until blood pressure lower than 160/95 mmHg was achieved. After this period the patients were observed for a minimum of 8 weeks. The mean length of the study was of 22 weeks. RESULTS: Both drugs significantly reduced blood pressure without modifying cardiac frequency. Doxazosin tended to favorably modify the lipid profile of the plasma while enalapril significantly reduced the levels of cholesterol, lipids and high density lipoproteins (HDL). Upon termination of the study the total HDL/cholesterol index increased 8.6% in those treated with doxazosin and decreased 5.5% in those receiving enalapril (p < 0.05). CONCLUSIONS: Although doxazosin and enalapril are potent antihypertensive drugs, the effects on plasma lipid obtained with doxazosin indicate that a reduction in cardiovascular risk was achieved with this drug in the patients included in this study.  相似文献   
106.
Presents a new one-memory quaternary four-state trellis code, and its four-state binary equivalent code based on a QAM constellation which is 0.52 dB better than the four-state Ungerboeck code.<>  相似文献   
107.
Cerebral hemodynamic changes in infants with progressive hydrocephalus have been studied with the transcranial Doppler (TCD) technique. Several authors have referred to the correlation between the hemodynamic changes and increased intracranial pressure (ICP). Despite conflicting conclusions on the value of pulsatility index (PI) and resistance index (RI) measurements for monitoring infantile hydrocephalus, these pulsatility indices are the most commonly used for this purpose. Although clinical signs of raised ICP are highly variable and unreliable in infants, assumptions have been made in most of the studies about the presence of elevated ICP on the basis of the patient's clinical state. Few studies have reported on actual ICP values, however, and a direct relationship between ICP and TCD changes has never been adequately demonstrated. In the present study, this relationship was investigated in long-term simultaneous TCD/ICP measurements, in an attempt to develop a noninvasive method of monitoring the effect of ICP on intracranial hemodynamics. Two groups of data sets were established. Group I consisted of pre- and postoperative (shunt implantation) TCD/ICP measurements. Group II were long-term simultaneous TCD/ICP recordings showing significant ICP variations. In most of the postoperative measurements there was a decrease in the average PI and RI values. The correlation between PI or RI and ICP in the long-term simultaneous recordings, however, was generally poor. The risk of obtaining false positive or false negative PI or RI values in short-term measurements was also demonstrated. It can be concluded from our results, besides the wide range of reference values for the Doppler indices and extracranial influences upon them, that the present Doppler indices are inadequate for monitoring the complex intracranial dynamic responses in patients with raised ICP.  相似文献   
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Exhaled air condensate provides a noninvasive means of obtaining samples from the lower respiratory tract. Hydrogen peroxide (H2O2) in exhaled air has been proposed as a marker of airway inflammation. We hypothesized that in stable asthmatic children the H2O2 concentration in exhaled air condensate may be elevated as a result of airway inflammation. In a cross-sectional study, 66 allergic asthmatic children (of whom, 41 were treated with inhaled steroids) and 21 healthy controls exhaled through a cold trap. The resulting condensate was examined fluorimetrically for the presence of H2O2. All subjects were clinically stable, nonsmokers, without infection. The median H2O2 level in the exhaled air condensate of the asthmatic patients was significantly higher than in healthy controls (0.60 and 0.15 micromol, respectively; p<0.05), largely because of high values in the stable asthmatic children who did not use anti-inflammatory treatment (0.8 micromol; p<0.01 compared to controls). We conclude that hydrogen peroxide is elevated in exhaled air condensate of children with stable asthma, and may reflect airway inflammation.  相似文献   
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