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121.
122.
A 91-year-old Chinese man developed bilateral lower limb oedema due to venous obstruction resulting from a distended urinary bladder. After the bladder was decompressed by urethral catheterisation, the bilateral lower limb oedema promptly subsided. Although a distended urinary bladder is a rare cause of bilateral lower limb oedema, it can be easily recognised by palpation of the lower abdomen and the relief of symptoms by urethral catheterisation is most rewarding.  相似文献   
123.
Early recognition of heart failure is important because early treatment reduces mortality and hospitalization rates. In screening for this disease, there is a need for a simple, safe, and cost-effective method to obtain cardiovascular variables. Therefore we developed a noninvasive impedance cardiographic method to predict the pulmonary capillary wedge pressure (PCWP) from the impedance cardiogram. The impedance cardiographic technique, though, was originally designed for stroke volume (SV) determination. The objectives of this study were to validate both variables by comparison with the paired, invasively obtained equivalents. PCWP, measured with a pulmonary artery catheter, was related to the O/C ratio from the impedance cardiogram. The O/C ratio was calculated as the amplitude of the impedance cardiogram during diastole (O) divided by the maximum height during systole (C). Stroke volume was also calculated from the impedance cardiogram according to the equation of Kubicek (SVIC) and compared with thermodilution (SVTD). Data analysis was performed in 24 stable patients who underwent diagnostic heart catheterization. Linear regression analysis showed that the O/C ratio was strongly related to the invasively measured PCWP over a range of 3 to 30 mm Hg (r = 0.92, standard error of the estimate, 3.2 mm Hg). Between SVIC and SVTD a moderate correlation was established (r = 0.69), but after exclusion of the data from patients with an aortic valve disorder (n = 5), the correlation increased considerably (r = 0.87). No significant differences between SVIC and SVTD were found (mean difference +/- 2 SD = 1.8 +/- 28.8 ml). These preliminary observations suggest that impedance cardiography can predict PCWP and measure SV over a wide range of clinically relevant values. The combined measurement of SV and PCWP by impedance cardiography might be a clinical useful tool in screening for heart failure.  相似文献   
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125.
Typical and atypical carcinoids (TC, ATC) and small (SCLC) and large cell neuroendocrine carcinomas (LCNEC) constitute the spectrum of neuroendocrine lung tumors. Chromosomal aberrations have not been studied in LCNEC and only rarely in carcinoids. Only SCLCs have been investigated frequently for chromosomal aberrations. We compared three typical and four atypical carcinoids, one atypical carcinoid/SCLC mixed type, three SCLC, and three LCNEC for chromosomal gains and losses using comparative genomic hybridization. Typical carcinoids showed either no changes or only few chromosomal gains. Atypical carcinoids appeared genetically heterogeneous: One case had no aberrations, and three cases had few aberrations; two of them showed a deletion of 11q. SCLC and LCNEC were characterized by many gains and losses, especially similar changes of 3p, 5q, 5p, and 13q. Although ATC resemble LCNEC morphologically, there were no similarities at the genetic level. We have found a reciprocal relationship of prognosis and the amount of aberrations. TCs and ATCs with few chromosomal changes have the best prognosis, whereas SCLCs and LCNECs were generally characterized by a great amount of aberrations and worst prognosis. There was no unbalanced aberration common in all types of neuroendocrine tumors of the lung.  相似文献   
126.
BACKGROUND: Desflurane anesthesia can produce cerebral metabolic depression and increase cerebral blood flow. We evaluated the effect of desflurane on brain tissue oxygen pressure (PO2), carbon dioxide pressure (PCO2) and pH during neurosurgery. METHODS: Following a craniotomy, the dura was opened and a Paratrend 7 sensor, which measures PO2, PCO2, pH and temperature, was inserted into brain tissue. In 6 control patients in group 1, anesthesia was maintained constant with 3% end-tidal desflurane over 60 min, including a 30-min stabilization period. In group 2, 9 patients were ventilated with 3% desflurane under baseline conditions. After a 30-min stabilization period, baseline tissue gases and pH were measured and end-tidal desflurane was increased to 6% and then 9% for 15-min intervals. Mean arterial pressure (MAP) was maintained with intravenous phenylephrine. RESULTS: Under baseline conditions, cardiovascular and brain tissue measures were similar between the 2 groups. Increasing end-tidal desflurane from 3% to 9% produced burst-suppression EEG in all patients and significantly increased tissue PO2 and pH and decreased PCO2. No parameters changed significantly in the control group during steady-state anesthesia. CONCLUSION: These results show that 9% desflurane can improve brain tissue metabolic status before temporary brain artery occlusion if cerebral perfusion pressure is maintained. This may be particularly important in patients with symptoms of ischemia before surgery.  相似文献   
127.
Cysteine protease activity in mycelial culture increased 7.7-fold after fruit body formation in Pleurotus ostreatus, using the Leu pNA (LPNA) cleavage assay. The enzyme was purified from fruit bodies and its M(r) was 97,000 by gel filtration and 48,500 by SDS-PAGE, indicating that it is a dimer. The enzyme was sensitive to iodoacetic acid, p-chloromercuribenzoate, N-ethylmaleimide, and HgCl2. The sequence of the first 9 N-terminal amino acids of cysteine protease was ASGLXXAIL.  相似文献   
128.
Various dates on amoxicillin (resorption, distribution, elimination, tissue passage, urinary excretion) are presented. The bacterial spectrum is more fully discussed. Amoxicillin is compared with ampicillin. Dosage and therapeutical results are presented. Within repeated bronchoscopic examinations necessary on account of bronchopulmonary affections determination of germs were done in 88 children. At the same time examination of ampicillin levels in bronchial secretions were performed after amoxicillin therapy with different high doses (3 x 125 mg to 3 x 750 mg) for 7 days. It could be shown that good antibiotic levels could be found in secretion specimens above all obtained 2 to 4 hours after the last amoxicillin administration. They could be found too, if there did not exist any purulent secretion or stronger inflammation. There are relations between the amount of dosage, the level in secretion as well as the influence on germs.  相似文献   
129.
The widespread use and dramatic success of prosthetic joint implant surgery (arthroplasty) has greatly improved the quality of life for many individuals suffering from degenerative, arthritic, or injured joints. However, in a number of cases, recipients experience discomfort at the arthroplasty site that can signal biomechanical failure, or periprosthetic infection of the joint, or both. In fact, infection remains a devastating obstacle, preventing arthroplasty from being an almost perfect medical procedure. Existing tests for the diagnosis of infection in orthopedics are disappointing because of the relatively high frequency of false negative results. To overcome this shortcoming, and to reduce the number of infected revision arthroplasties, a methodology based on molecular biology has been established. The method allows the rapid, sensitive and accurate diagnosis of orthopedic infections, and should aid the clinician with treatment regimens, surgical decisions, and overall patient management in the growing arthroplasty population.  相似文献   
130.
BACKGROUND: While there is substantial evidence that psychological stress enhances risk for coronary artery disease, the mechanisms underlying such an influence remain unclear. We examined the effects of short-term psychological stress on serum lipid levels, hemoconcentration, fibrinogen level, and plasma viscosity. METHODS: Forty-four healthy young adults were randomly assigned to perform a distinctly frustrating cognitive task for 20 minutes (stress condition) or to rest quietly for the same period (control condition). RESULTS: Relative to controls, stressed subjects showed significant increases in blood pressure and heart rate; total, low-density, and high-density lipoprotein cholesterol levels; hematocrit; hemoglobin level; and total protein concentration. Stressed subjects also showed significant reductions in plasma volume and increased plasma viscosity and estimated whole-blood viscosity compared with controls. A similar trend in fibrinogen level was not statistically significant. Individual differences in blood pressure and heart rate response to stress correlated highly with changes in total cholesterol levels and hematocrit. CONCLUSIONS: Our investigation provides further evidence that exposure to short-term mental stress elicits hemoconcentration with associated increases in serum lipid concentrations, hemostatic factors, and blood viscosity.  相似文献   
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