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排序方式: 共有10000条查询结果,搜索用时 343 毫秒
141.
B.H. Lim MRCOG FRNZCOG C.L. Barry MBBS G.H. Brown MRCOG 《The Australian & New Zealand journal of obstetrics & gynaecology》1991,31(1):20-21
We describe a case of preeclampsia with the HELLP (Haemolysis, Elevated Liver enzymes, Low Platelets) syndrome and highlight the delayed diagnosis due to its nonspecific presentation. This syndrome is associated with significant maternal and perinatal mortality and morbidity and we discuss the importance of early recognition of the condition, aggressive management and a multidisciplinary approach. 相似文献
142.
Analysis of the Streptomyces coelicolor sigE gene reveals the existence of a subfamily of eubacterial RNA polymerase sigma factors involved in the regulation of extracytoplasmic functions. 总被引:18,自引:1,他引:17
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143.
S P Brown E R Anderson Q He S Liu Q Wu H Li R Whittle 《The Journal of sports medicine and physical fitness》1992,32(3):288-292
To compare the oxygen cost of submaximal exercise on the Stairobic stepping (SS) machine with bench stepping (BS), 12 healthy men and women (mean age 23 years) underwent six different five minute exercise bouts that were randomly assigned. Tests were conducted using standard open circuit calorimetry. SS at 40 and 60 st/min was equal to BS at 20 st/min and SS at 80 st/min was equal to BS at 30 st/min for VE and RER. VO2 was equal at 20 st/min (BS) and 60 st/min (SS), and 30 st/min (BS) and 80 st/min (SS). Stairobic MET (SM) displayed values over-estimated actual MET (AM) values at the two lowest SS rates and under-estimated the AM value at the highest SS rate. Forty-eight observations of the MET response of SS were conducted and analyzed (BMDP2R) in a forward stepping solution. The multiple regression equation calculated for AM was: AM = -0.567 + -0.012 (WT) + 0.063 (rate) + 0.612 (SM) with an adjusted R2 of 0.82 and a SEE of 0.90. The physiologic cost of BS was approximately equal to SS at two to three times the BS rate of stepping. 相似文献
144.
Mycosis fungoides (MF) is a malignant T-cell lymphoma that primarily involves the skin, but may, in its advanced stages, metastasize to internal organs. From autopsy series, CNS involvement of MF can be seen in 14% of patients. We describe the CT and MR findings in three patients with CNS metastases. The images showed various manifestations of CNS MF, including parenchymal homogeneously intensely enhancing masses and ependymal enhancement. The CSF and biopsy results were eventually diagnostic in all three cases. One patient was treated prior to pathologic diagnosis, the other two were treated after diagnosis. The tumor improved following treatment in two patients. Although the imaging findings of CNS MF are nonspecific, they can be the first evidence of the disease. 相似文献
145.
The effect of restraint on the activation of macrophages was evaluated based on the induction of I-A expression following injection of viable Mycobacterium bovis (strain BCG) or treatment in vitro with recombinant interferon-gamma (rIFN-gamma). We found that restraint suppressed the induction of I-A expression when applied just prior to or at the same time as the injection of the microorganisms but had no effect if applied after the injection of the Mycobacteria. The effect of stress was attenuated by increasing the number of microorganisms or by incubating macrophages from stressed mice with higher doses of rIFN-gamma. The suppressive effect of restraint does not appear to be associated with uptake, processing or presentation of antigen but rather to an alteration in the response of the macrophages to rIFN-gamma. 相似文献
146.
Effects of inotropes on human leucocyte numbers, neutrophil function and lymphocyte subtypes 总被引:1,自引:1,他引:0
Burns A. M.; Keogan M.; Donaldson M.; Brown D. L.; Park G. R. 《British journal of anaesthesia》1997,78(5):530-535
We have investigated the effects of inotropes with different adrenergic
receptor specificity on differential white cell count, lymphocyte subtypes
and neutrophil function in healthy volunteers. Six healthy, male volunteers
were enrolled into this randomized, placebo-controlled pilot study. Each
volunteer was studied on four separate occasions during a 2-h infusion of
various agents, and for 2 h after stopping the infusion. The agents
investigated were adrenaline 0.1 microgram kg-1 min-1, dobutamine 5
micrograms kg-1 min-1, dopexamine 2 micrograms kg-1 min-1 and 5% glucose
0.5 ml kg-1 h-1. Venous blood was sampled at 0, 30, 120 and 240 min.
Haemodynamic monitoring was continued throughout the study. Full blood
count, white cell differential count and enumeration of lymphocyte subtypes
were performed. Neutrophil function tests included chemoluminescence, and
assessment of neutrophil chemotaxis, phagocytosis and adhesion. The
Wilcoxon signed rank test was used to compare differences between placebo
and active drugs at each time compared with baseline. There was a
significant increase in white cell count, lymphocyte count and neutrophil
count with adrenaline, and a small but significant decrease in these
variables with dobutamine and dopexamine. These changes were also apparent
for absolute CD3+, CD4+ and CD8+ lymphocyte counts. Neutrophil respiratory
burst in response to f-methionyl-leucyl-phenylalanine increased
significantly only with adrenaline at 30 min (P = 0.046). There were no
other significant changes in tests of neutrophil function. Infusion of
inotropes was associated with changes in white cell numbers, lymphocyte
subtypes and neutrophil respiratory burst. In healthy volunteers,
adrenaline had effects different from those of dobutamine and dopexamine.
The clinical relevance of such effects requires further investigation in
critically ill patients.
相似文献
147.
Color Doppler imaging of the ocular ischemic syndrome. 总被引:12,自引:0,他引:12
A C Ho W E Lieb P M Flaharty R C Sergott G C Brown T M Bosley P J Savino 《Ophthalmology》1992,99(9):1453-1462
PURPOSE: This study describes hemodynamic characteristics of the ophthalmic, central retinal, and posterior ciliary arteries in 16 eyes of 11 patients with the ocular ischemic syndrome. Understanding the hemodynamic characteristics of the retrobulbar circulation may elucidate the natural history and pathophysiology of the ocular ischemic syndrome and perhaps form the basis for rational treatment of this condition. METHODS: Color Doppler imaging, a procedure that permits rapid noninvasive imaging of the ophthalmic, central retinal, and posterior ciliary arteries, was used to quantitate peak systolic blood flow velocities and vascular resistance (pulsatility index) within these vessels in study group eyes and in an age-matched control population. RESULTS: We demonstrated markedly reduced ocular ischemic syndrome central retinal and posterior ciliary artery peak systolic velocities compared with control group eyes. Central retinal and posterior ciliary artery vascular resistance (pulsatility index) was greater in ocular ischemic eyes versus control group eyes. Reversal of ophthalmic artery blood flow was detected in 12 of 16 ocular ischemic syndrome eyes. Study group eyes with poor vision had no detectable posterior ciliary arterial blood flow. CONCLUSION: Color Doppler imaging quantitates hemodynamic characteristics of the retrobulbar circulation in the ocular ischemic syndrome. There is markedly reduced peak systolic velocity and increased vascular resistance in ocular end arteries such as the central retinal and posterior ciliary arteries. Ophthalmic artery reversal of flow seems to represent collateral blood flow to lower resistance vascular beds. Posterior ciliary artery hypoperfusion may correlate with poor vision in the ocular ischemic syndrome. 相似文献
148.
T M Kim H R Brown S H Lee C V Powell P Bethune N L Goller H T Tran J S Mackay 《Modern pathology》1992,5(3):348-352
A 9-yr-old girl developed delayed acute measles inclusion body encephalitis, which was different from subacute sclerosing panencephalitis (SSPE) in clinical course. Measles virus was demonstrated by electron microscopy, immunohistochemistry, and in situ hybridization. Contrary to the most previous reports, matrix (M) protein was present in the brain, cerebrospinal fluid, and serum and was demonstrated by Western blot analysis and in situ hybridization. The hybridization was performed by a nonradioactive digoxigenin method. 相似文献
149.
150.
Feline hyperthyroidism bears a strong clinical and pathologic resemblance to toxic nodular goiter in humans. To evaluate whether the observed thyroid growth might be due to circulating thyroid antibodies, as has been postulated in humans, we studied the effect of purified immunoglobulin (Ig) G preparations on a rat thyroid follicular (FRTL-5) cell line. When compared with control, hyperthyroid cat IgG caused significantly increased [3H]-thymidine (Tdr) incorporation into DNA (p less than 0.02) and stimulated cellular proliferation 15-fold. Stimulation of 3H-Tdr incorporation tended to be biphasic and could be inhibited completely by a potent, specific TSH receptor blocking antibody. Hyperthyroid cat IgG also significantly inhibited 125I-bTSH binding to porcine thyroid membranes, an effect that could be reproduced using electrophoretically pure IgG and normal cat thyroid membranes. Unlike its effect on growth, hyperthyroid cat IgG did not stimulate intracellular cAMP, and there was no correlation between thyroid function in vivo and IgG growth-promoting activity in vitro. These data suggest that elevated titers of thyroid growth IgGs, probably acting through the TSH receptor, are present in feline hyperthyroidism and may play a role in goiter formation. Unlike growth, the thyroid hyperfunction observed is not IgG dependent. Further study of feline hyperthyroidism may contribute important insights into human nodular goiter and into the mediation of thyroid growth in general. 相似文献