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981.
KV Sha?tan NK Balabaev AS Lemak MD Ermolaeva AG Iva?kina MV Orlov EV Gel''fand 《Canadian Metallurgical Quarterly》1997,42(1):47-53
The purpose of this study was to assess the accuracy of chest x-ray (CXR) interpretation in the diagnosis of pneumocystis carinii pneumonia (PCP), bacterial pneumonia (BP), and pulmonary tuberculosis (TB) in human immunodeficiency virus (HIV)-positive patients and to identify the frequency with which these infections mimic one another radiographically. The admitting CXRs of 153 HIV-positive patients with laboratory proven BP (n = 71), PCP (n = 73), and TB (n = 9) and those of 10 HIV-positive patients with no active disease were reviewed retrospectively and independently by three radiologists who were blinded to clinical and laboratory data. Median percent accuracies were as follows: TB, 84%; PCP, 75%; BP, 64%; and no active disease, 100%. Fifteen of 153 cases (9.8%) were shown to mimic other infections radiographically. A confident and accurate diagnosis can be made radiographically in the majority of cases of PCP, BP, and TB in HIV-positive patients at the time of hospitalization. In approximately 10% of cases, these infections may mimic one another radiographically. 相似文献
982.
The kinase domain of Jak2 mediates induction of bcl-2 and delays cell death in hematopoietic cells 总被引:1,自引:0,他引:1
Granulocyte-macrophage colony-stimulating factor (GM-CSF), interleukin (IL)-3, and IL-5 stimulate DNA synthesis and proliferation and inhibit apoptosis in hematopoietic cells. Multiple signal pathways are activated by binding of these ligands to their receptors, which share a common beta subunit. Janus protein kinase 2 (Jak2) binds to the membrane proximal domain of the beta chain and is phosphorylated on receptor ligation. To explore the role of Jak2 in the regulation of specific signal transduction pathways, we constructed fusion proteins with a CD16 external domain, a CD7 transmembrane region, and a Jak2 cytoplasmic domain. This cytoplasmic domain consisted either of wild type Jak2 (CD16/Jak2-W) or Jak2 mutations with deletions of (a) the amino terminus (CD16/Jak2-N), (b) kinase-like domain (CD16/Jak2-B), (c) kinase domain (CD16/Jak2-C), or (d) amino-terminal and kinase-like domains, leaving the kinase domain (CD16/Jak-K) intact. In contrast to the CD16/Jak2-W fusion protein, which requires cross-linking for activation, CD16/Jak2-N, CD16/Jak2-B, and CD16/Jak2-K were constitutively phosphorylated, and they stimulated Shc phosphorylation and increased binding of STAT to DNA in Ba/F3 cells. Cell lines derived from IL-3-dependent Ba/F3 cells stably transfected with CD16/Jak2-W, CD16/Jak2-N, or CD16/Jak2-B mammalian expression vectors died at a rate similar to that of the parental cells on IL-3 deprivation. In contrast, CD16/Jak2-K cell lines exhibited increased expression of bcl-2 and pim-1 mRNA and maintained their viability when compared with control cell lines. Thus, activation of tyrosine phosphorylation by creating a CD16/Jak2-K fusion is sufficient to activate pathways that prevent cell death. 相似文献
983.
984.
This article explores dynamic versus static biomechanics, quantitative versus qualitative data, and practical uses in a clinical setting for the Vector System of gait analysis. This system uses a video camera connected to a computer to analyze gait. 相似文献
985.
Hospital mortality analysis in patients with different kinds of bradyarrhythmias after electrocardiopacemaker implantation operation performance was conducted. Significant haemodynamics improvement did not occur, if the patients had the pronounced coronary atherosclerosis. It was concluded that combined surgical correction of this pathology is needed. 相似文献
986.
Discusses the problems related to the theoretical validation of selecting a method of investigation, its application with due consideration for the algorithm of osteological identification, and assessment of the results of this or that method from the viewpoint of the objectiveness and informative value of the method for osteological identification. 相似文献
987.
988.
ShSh Eliava KG Oganesian AA Dausheva IuM Filatova SP Zolotukhin OB Belousova VG Amcheslavski? GI Toma AS Saribekian 《Canadian Metallurgical Quarterly》1998,157(3):15-19
The influence of serotonin adipinate on the mechanisms of development of tissue hypoxia, disturbances of the microcirculatory bed and smooth muscles before, during and after operative interventions was studied in experiments and clinical practice. The syndrome of serotonin insufficiency is described including smooth muscle insufficiency which can be abolished by serotonin adipinate administered at the early postoperative period irrespective of the cause of surgery, age and sex of the patient. Good results were obtained in treatment of patients after operations on the liver, pancrease, heart, in patients with the diabetic foot and in other diseases. No complications or lethal outcomes resulting from using serotonin adipinate were noted. 相似文献
989.
The dimensions of the apical surfaces of hair cells were measured in guinea pigs, aged from 3 weeks before term to 25 weeks after birth. In the basal two-thirds of the cochlea, the apical surfaces of the outer hair cells and their supporting cells changed with age, shrinking in a direction radial across the cochlear duct. There was an associated widening of the angle of the 'V' of the rows of stereocilia. Further apically, between 12 and 16 mm from the base of the cochlea, the outer hair cells and their supporting cells underwent the opposite change, becoming wider in a radial direction with age. The changes were seen before birth and continued for more than 3 weeks after birth. The results suggest that the guinea pig cochlea continues certain developmental processes for a considerable time after birth. 相似文献
990.