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101.
BACKGROUND: Organ transplant recipients who are seropositive for cytomegalovirus (CMV) and who are treated with antilymphocyte antibody (ALA) therapy have a high rate of symptomatic CMV disease. The intravenous administration of ganciclovir therapy once daily during ALA therapy decreased the incidence from 24% to 10% in patients receiving ALA as an induction therapy and from 64% to 22% in those treated for rejection. The present study was undertaken to determine whether a more intensive and sustained antiviral regimen could be more effective. METHODS: From April 1995 to December 1997, all CMV seropositive renal and liver transplant recipients who received ALA therapy were treated with intravenously administered ganciclovir (5 mg/kg/day with dose adjusted for renal dysfunction) for the length of ALA therapy and then with orally administered acyclovir (400 mg three times/day) or ganciclovir (1 gm twice/day) for 3 to 4 months. The incidence of CMV viremia and of CMV disease was determined during the 6 months after completion of ALA therapy. RESULTS: Forty-one patients (35 renal and 6 liver transplant recipients) were studied. CMV disease occurred in 2 patients (4.9%), both of whom were treated for rejection; it occurred in 1 of 21 patients (4.8%) treated with orally administered acyclovir, and in 1 of 20 patients (5%) treated with orally administered ganciclovir. The only patient who developed CMV disease in the ganciclovir group had received only 26 days of oral antiviral therapy. No CMV disease was documented in the group of patients receiving ALA therapy as induction therapy. CMV viremia occurred in three patients in the acyclovir group (14.3%) and in one patient in the ganciclovir group (5%). Among renal transplant recipients only, 1 of 35 patients developed CMV disease (2.9%) and no case of CMV disease was documented in patients treated with orally administered ganciclovir. All six patients receiving two courses of ALA therapy each were free of CMV disease. Toxicity of the regimen was minimal, and antiviral resistance did not develop. CONCLUSIONS: Preemptive antiviral therapy with intravenously administered ganciclovir during ALA therapy and then orally administered ganciclovir for 3 to 4 months provides virtually complete protection against the excessive rate of CMV disease that occurs in CMV seropositive allograft recipients receiving ALA therapy.  相似文献   
102.
Twenty de novo patients with Parkinson's disease (Hoehn-Yahr stages I, II, III) were studied in a double blind trial after introducing (--)-deprenyl monotherapy. The parkinsonian symptoms were assessed by a novel graded clinical rating scale, by UPDRS and by the North Western self-rating scale. A significant change was observed in motor behaviour and daily activity (UPDRS) after 3 weeks of treatment with (--)-deprenyl at 10 mg/day. The total scores using UPDRS and the North Western ratings were changed significantly after 4 weeks. The greatest changes observed were in walking and in hypokinesia. Rigidity was not modified by (--)-deprenyl.  相似文献   
103.
104.
PURPOSE: To evaluate the usefulness of Doppler ultrasonography (US) in the diagnosis of hyperfiltration in patients with insulin-dependent diabetes mellitus (IDDM). MATERIALS AND METHODS: Eighty-one consecutive patients with IDDM were studied. All patients were normotensive and had normal creatinine and blood urea nitrogen levels. The glomerular filtration rate (GFR) was evaluated by means of plasma clearance of chromium-51 ethylenediaminetetraacetic acid, urinary albumin excretion, US evaluation of renal volume, and Doppler evaluation of resistance index (RI) in the renal interlobar arteries. The patients were divided according to GFR into the following groups: those with hyperfiltering kidneys (group 1, n = 40) and those with normofiltering kidneys (group 2, n = 41). RESULTS: The median renal volume was 351 mL (95% CI = 337 mL, 379 mL) in group 1 and 318 mL (95% CI = 300 mL, 335 mL) in group 2 (P = .005). The number of patients with microalbuminuria was significantly lower in group 1 than in group 2 (P = .02). The median RI was significantly lower in group 1 (0.55; 95% CI = 0.53, 0.57) than in group 2 (0.57; 95% CI = 0.56, 0.59) (P = .04). An RI of less than 0.5, a renal volume greater than 410 mL/m2, and the absence of microalbuminuria were independent predictors of hyperfiltration. An RI of less than 0.5 and a renal volume greater than 410 mL/m2 showed high specificity (98% and 95%, respectively) and poor sensitivity (25% and 23%, respectively) in the diagnosis of hyperfiltration in IDDM patients. CONCLUSION: Both RI and renal volume showed correlation with GFR, but neither parameter is sufficiently sensitive in screening for hyperfiltration in IDDM patients.  相似文献   
105.
A 4-year-old boy presented with sudden onset of fever, pyuria, and bacteriuria. Ultrasound revealed left hydronephrosis and hydroureter. A plain abdominal radiography and excretory urogram showed a giant ureteral stone measuring 9 cm causing ureteral obstruction. Underlying anatomic or metabolic abnormalities were not detected. Extraction of the stone resulted in complete disappearance of the hydronephrosis and hydroureter.  相似文献   
106.
The strain Methylobacter bovis 98 was selected among methanotrophic bacteria as one of the most active producers of secretory bacteriocin-like compounds. In the above strain this compound was shown to be a protein with a molecular weight of about 70 kD, relatively thermostable, having a bactericidal effect on closely related organisms. Its properties as a whole are consistent with the accepted definition of bacteriocins, which so far have not been found in this group of microorganisms. A methodical approach that combines electrophoretic separation of secretory proteins and testing their antibacterial activity directly in polyacrylamide gel allowed us for the first time to identify bacteriocin in methanotrophic bacterial culture.  相似文献   
107.
Serial electrocardiographic (ECG) changes are a critical component of the diagnostic algorithm for classification of myocardial ischemic events in large-scale clinical trials. This study describes a computerized serial ECG classification program developed at the St. Louis University Core ECG Laboratory for use in the Bypass Angioplasty Revascularization Investigation (BARI) trial, in which patients with multivessel coronary artery disease were randomized to receive either coronary artery bypass grafting or percutaneous transluminal coronary angioplasty. The St. Louis University program detects and codes serial changes in Q, ST, and T wave items according to Minnesota code (MC) criteria using a modified NOVACODE hierarchical classification system. Measurements using a seven-power calibrated coding loupe are used to generate the MC from a customized software program. Significant minor or major changes are detected by the serial comparison program and referred to a physician coder for verification. Serial comparison coding rules are used to adjust for weaknesses in the standard MC classification system resulting from instability at decision boundaries. Of 4,244 BARI randomized and registry study participants with follow-up ECGs received at the Core ECG Laboratory as of March 1995, a grade 2 MC Q wave progression was noted in 568 participants (13.4%) using MC criteria alone, as compared with 367 (8.6%) after the St. Louis University coding rules were applied. The incidence of grade 1 MC Q wave progressions was 16.4% (697/4,244) versus 6.1% (259/4,244) when the St. Louis University program was applied. Intraobserver variability for grade 2 Q wave progression codes determined from a sample of 812 serial.  相似文献   
108.
We examined the regulation of collagenase production by the monocyte/macrophage THP-1 cell line when these cells were exposed to poly(2-hydroxyethyl methacrylate) (PHEMA) hydrogel surfaces with different chemistries and morphologies. Tissue culture modified polystyrene (TCP), used as a control surface, induced the maximum collagenase response. Copolymer hydrogels containing 2-ethoxyethyl methacrylate (EMA) or methyl methacrylate (MMA) also induced a high response, while PHEMA hydrogels induced a low level response and the phosphorylated hydrogel induced no response. This pattern was altered when the morphology of the hydrogels was changed to that of a sponge. The overall enzyme response to the sponge hydrogels was lower than that to the homogeneous hydrogels. Sponges containing EMA and MMA produced low level response relative to the TCP control. PHEMA and phosphorylated sponges produced little and no response respectively. The dramatically reduced enzyme response to phosphorylated surfaces was not a consequence of cell death, and may be a phenomenon related to changes in cell surface charge.  相似文献   
109.
The islets of Langerhans contain four distinct endocrine cell types producing the hormones glucagon, insulin, somatostatin and pancreatic polypeptide. These cell lineages are thought to arise from a common, multipotential progenitor cell whose identity has not been well established. The pancreatic and intestinal hormone, peptide YY, has been previously identified in glucagon-producing cells in islets; however, transgenic mice expressing Simian Virus 40 large T antigen under the control of the peptide YY gene expressed the oncoprotein in beta, delta and pancreatic polypeptide cells, and occasionally developed insulinomas, suggesting relationships between peptide YY-producing cells and several islet cell lineages. The four established pancreatic islet cell types were examined for coexpression of peptide YY in islets of normal and transgenic mice throughout development. Peptide YY immunoreactivity was identified in the earliest endocrine cells in the fetal pancreas and was coexpressed in each islet cell type during development. Peptide YY showed a high degree of co-localization with glucagon- and insulin-producing cells in early pancreatic development, but by adulthood, peptide YY was expressed in less than half of the alpha cells and was no longer expressed in beta cells. Peptide YY was also coexpressed with somatostatin and pancreatic polypeptide when these cell types first appeared, but most delta and pancreatic polypeptide cells continued to express peptide YY throughout development. The use of conditions that distinguish peptide YY from the related peptides, pancreatic polypeptide and neuropeptide Y, as well as the ability of the peptide YY gene to direct expression of a reporter gene in islets of transgenic mice, establishes expression of peptide YY in the earliest pancreatic endocrine cells.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
110.
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