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101.
Unlike other forms of tuberculosis, tuberculous cerebral abscess is a rare complication of human immunodeficiency virus (HIV) infection and usually presents at a late stage of the disease. This article describes a case of tuberculous cerebral abscess in an HIV-infected patient that was effectively treated with surgery and chemotherapy. The patient has survived more than 5 1/2 years since being diagnosed and remains in good health. 相似文献
102.
MS Pearle HL Pierce GL Miller JA Summa JM Mutz BA Petty CG Roehrborn JV Kryger SY Nakada 《Canadian Metallurgical Quarterly》1998,160(4):1260-1264
PURPOSE: We compare the efficacy of percutaneous nephrostomy with retrograde ureteral catheterization for renal drainage in cases of obstruction and infection associated with ureteral calculi. MATERIALS AND METHODS: We randomized 42 consecutive patients presenting with obstructing ureteral calculi and clinical signs of infection (temperature greater than 38 C and/or white blood count greater than 17,000/mm.3) to drainage with percutaneous nephrostomy or retrograde ureteral catheterization. Preoperative patient and stone characteristics, procedural parameters, clinical outcomes and costs were assessed for each group. RESULTS: Urine cultures obtained at drainage were positive in 62.9% of percutaneous nephrostomy and 19.1% of retrograde ureteral catheterization patients. There was no significant difference in the time to treatment between the 2 groups. Procedural and fluoroscopy times were significantly shorter in the retrograde ureteral catheterization (32.7 and 5.1 minutes, respectively) compared with the percutaneous nephrostomy (49.2 and 7.7 minutes, respectively) group. One treatment failure occurred in the percutaneous nephrostomy group, which was successfully salvaged with retrograde ureteral catheterization. Time to normal temperature was 2.3 days in the percutaneous nephrostomy and 2.6 in the retrograde ureteral catheterization group, and time to normal white blood count was 2 days in the percutaneous nephrostomy and 1.7 days in the retrograde ureteral catheterization group (p not significant). Length of stay was 4.5 days in the percutaneous nephrostomy group compared with 3.2 days in the retrograde ureteral catheterization group (p not significant). Cost analysis revealed that retrograde ureteral catheterization was twice as costly as percutaneous nephrostomy. CONCLUSIONS: Retrograde ureteral catheterization and percutaneous nephrostomy effectively relieve obstruction and infection due to ureteral calculi. Neither modality demonstrated superiority in promoting a more rapid recovery after drainage. Percutaneous nephrostomy is less costly than retrograde ureteral catheterization. The decision of which mode of drainage to use may be based on logistical factors, surgeon preference and stone characteristics. 相似文献
103.
F Scolari GM Ghiggeri G Casari A Amoroso D Puzzer GL Caridi B Valzorio R Tardanico V Vizzardi S Savoldi BF Viola N Bossini E Prati R Gusmano R Maiorca 《Canadian Metallurgical Quarterly》1998,13(10):2536-2546
BACKGROUND: The nephronophthisis-medullary cystic disease (NPH/MCD) complex represents a heterogeneous group of hereditary tubulointerstitial nephritis. The most common variant is juvenile recessive NPH, for which a gene locus (NPH1) has been mapped on chromosome 2q13. MCD is a less common dominant condition usually recognized later in life, which resembles NPH in many aspects, still presenting remarkable clinical differences. Nothing is known about the chromosome locus of MCD. METHODS: Five MCD families were studied. Diagnosis was made by inference from family history, type of inheritance, clinical signs and histology. Multipoint linkage analysis was performed by markers D2S293, D2S340 and D2S160 spanning the entire NPH1 locus. RESULTS: Diagnosis of MCD was made in 28 affected members (16 males; 12 females), belonging to five families. Histological diagnosis was available in 10 patients; clinical diagnosis in 11; seven deceased relatives had diagnosis of chronic nephritis. The age at diagnosis ranged from 8 to 65 years. Renal medullary cysts were found in a minority of patients. In family 1, the disease was associated with hyperuricaemia and gouty arthritis. Progression of renal disease presented intra- and extra-family variability with members of the same family showing mild elevation of creatinine or terminal renal failure. The NPH1 locus associated to recessive NPH was excluded from linkage to the dominant MCD. CONCLUSIONS: MCD might be more common than previously assumed. Variability in clinical presentation and absence of histopathological hallmarks contribute to make the diagnosis uncommon. The most remarkable clinical difference with NPH is the age of onset in some kindreds and a delayed progression towards renal failure. The exclusion of linkage to the NPH1 locus suggests the existence of an MCD responsible locus, still to be mapped. 相似文献
104.
C Kowalski S Zahler BF Becker A Flaucher PF Conzen E Gerlach K Peter 《Canadian Metallurgical Quarterly》1997,86(1):188-195
BACKGROUND: Polymorphonuclear neutrophils (PMNs) contribute to postischemic reperfusion damage in many organs and tissues, a prerequisite being adhesion of PMNs to vascular endothelial cells. Because adhesion processes involve orderly interactions of membrane proteins, it appeared possible that "membrane effects" of volatile anesthetics could interfere. We investigated the effects of halothane, isoflurane, and sevoflurane on postischemic adhesion of human PMNs in the intact coronary system of isolated perfused guinea pig hearts. METHODS: The hearts (n = 7-10 per group) were perfused in the "Langendorff" mode under conditions of constant flow (5 ml/min) using modified Krebs-Henseleit buffer equilibrated with 94.4% oxygen and 5.6% carbon dioxide. Global myocardial ischemia was induced by interrupting perfusion for 15 min. In the second minute of reperfusion (5 ml/min), a bolus dose of 6 x 10(5) PMNs was injected into the coronary system. The number of cells reemerging in the coronary effluent was expressed as a percentage of the total number of applied PMNs. Halothane, isoflurane, and sevoflurane, each at 1 and 2 minimal alveolar concentration (MAC), were vaporized in the gas mixture and applied from 14 min before ischemia until the end of the experiment. RESULTS: Under nonischemic conditions, 24.7 +/- 1.3% of the injected neutrophils did not reemerge from the perfused coronary system. Subjecting the hearts to global ischemia augmented retention (36.4 +/- 2.8%, P < .05). Application of halothane reduced adhesion of neutrophils to 22.6 +/- 2.1% and 24.2 +/- 1.8% at 1 and 2 MAC, respectively (P < .05). Exposure to 1 and 2 MAC isoflurane was similarly effective, whereas basal adhesion was not significantly influenced. Sevoflurane-treated hearts (1 and 2 MAC) also showed decreased adhesion of PMNs (23 +/- 2.3% and 24.8 +/- 1.8%, respectively; P < .05) and an identical reduction resulted when sevoflurane (1 MAC) was applied only with the onset of reperfusion. CONCLUSIONS: Although the mechanism of action of volatile anesthetics remains unclear in these preliminary studies, their inhibitory effect on ischemia-induced adhesion of PMNs may be beneficial for the heart during general anesthesia. 相似文献
105.
BF Volkman ME Anderson KD Clark Y Hayakawa MR Strand JL Markley 《Canadian Metallurgical Quarterly》1999,274(8):4493-4496
The structure of the recently identified plasmatocyte spreading peptide from the moth Pseudoplusia includens (PSP1) has been determined by NMR spectroscopy. This novel insect cytokine consists of 23 amino acid residues and a single disulfide bond. Torsion angle dynamics calculations utilizing a total of 337 distance constraints yielded an ensemble of 30 structures with an average backbone root mean square deviation for residues 7-22 of 0.18 A from the mean structure. The structure consists of a disordered N-terminal region and a well defined core that is stabilized by numerous hydrophobic interactions and a short beta-hairpin. Structural comparisons confirm that PSP1 adopts an epidermal growth factor (EGF)-like fold with close similarity to the C-terminal subdomain of EGF-like module 5 of human thrombomodulin. The combination of the three-dimensional structure of PSP1 and the extensive literature on EGF-receptor interactions should accelerate the process of identifying the specific residues responsible for receptor binding activity of this family of immunoregulatory peptides. 相似文献
106.
Bornmann Lutz Mutz Rüdiger Haunschild Robin de Moya-Anegon Felix de Almeida Madeira Clemente Mirko Stefaner Moritz 《Scientometrics》2021,126(11):9305-9331
Scientometrics - In over five years, Bornmann, Stefaner, de Moya Anegon, and Mutz (2014b) and Bornmann, Stefaner, de Moya Anegón, and Mutz (2014c, 2015) have published several releases of the... 相似文献
107.
A Schober R Günther A Schwienhorst M D?ring BF Lindemann 《Canadian Metallurgical Quarterly》1993,15(2):324-329
An assay using reversed-phase high-performance liquid chromatography with ultraviolet detection, at 278 nm, was developed to measure diclofenac in human plasma and urine at concentrations suitable for biopharmaceutical studies. Indomethacin was used as internal standard and separation was performed at 40 degrees C on a C18 Spherisorb column with acetonitrile-0.1 M sodium acetate (35:65, v/v) (pH 6.3) as mobile phase. The sample preparation is simple and rapid (extractionless), and the total run time is less than 5 min. The retention time is 2.8 min for diclofenac and 3.6 min for indomethacin. The detection limit is 0.2 microgram/ml using a 20-microliters loop. 相似文献
108.
Peptides were synthesized in which the type-specific determinant of the V3 loop region of gp120 (SP10) was expressed C terminal to a conserved T helper epitope (T1) on the same molecule. These T1-SP10 peptides can stimulate both cell-mediated and humoral immune responses. The current work used a novel approach to study the nature and specificity of the response elicited by these peptides. Cytokine-specific ELIspot assays were used to examine the number, kinetics and fine specificity of cells induced to secrete IL-4 and IL-6 in mice immunized with T1-SP10 peptides. Results indicate that the peptides activated cytokine-secreting cells in a dose-dependent manner in vivo. In vitro restimulation experiments demonstrated that both the SP10 and T1 regions contributed to this activation. Consistent with previous studies, mice sequentially immunized with peptides expressing different V3 loop regions generated B cell responses that were larger and more cross-reactive than those induced by a single peptide. Sequential immunizations had less effect on the number or specificity of the cytokine-producing cells. 相似文献
109.
110.
J Pintor BF King MT Miras-Portugal G Burnstock 《Canadian Metallurgical Quarterly》1996,119(5):1006-1012
1. Adenine dinucleotides (Ap3A, x = 2-6) are naturally-occurring polyphosphated nucleotidic substances which are found in the CNS and are known to be released in a calcium-dependent manner from storage vesicles in brain synaptosomes. The selectivity and activity of adenine dinucleotides for neuronally-derived recombinant P2 purinoceptors were studied using P2X2 and P2Y1 subtypes expressed in Xenopus oocytes. 2. For the P2Y1 subtype derived from chick brain, Ap3A was equipotent and as active as ATP (EC50 values: 375 +/- 86 nM and 334 +/- 25 nM, respectively). Ap4A was a weak partial agonist and other dinucleotides were inactive as agonists. None of the inactive dinucleotides were antagonists nor modulated the activity of Ap3A and ATP. 3. For the P2X2 subtype derived from rat PC12 cells, Ap4A was as active as ATP but less potent (EC50 values: 15.2 +/- 1 microM and 3.7 +/- 0.7 microM, respectively). Other adenosine dinucleotides were inactive as either agonists or antagonists. 4. Ap5A (1-100 nM) potentiated ATP-responses at the P2X2 subtype, showing an EC50 of 2.95 +/- 0.7 nM for this modulatory effect. Ap5A (10 nM) shifted the concentration-response curves for ATP to the left by one-half log10 unit but did not alter the Hill co-efficient for ATP (nH = 2.1 +/- 0.1). Ap5A (10 nM) failed to potentiate Ap4A-responses but did enhance the efficacy of the P2 purinoceptor antagonist, suramin, by 12 fold at the P2X2 subtype. 5. In conclusion, the results show that ionotropic (P2X2) and metabotropic (P2Y1) ATP receptors which occur in the CNS are activated selectively by naturally-occurring adenine dinucleotides which are known to be released with nucleotides from storage vesicles. The observed potentiation of P2X2-responses by Ap5A, where co-released with ATP by brain synaptosomes, may have a functional bearing in purinergic signalling in the CNS. 相似文献