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81.
We have studied the frequency and structure of cardiac rhythm (CR) disturbances in the women presenting with abdominal obesity (AO) in the postmenopausal period. The single-step study involved 210 postmenopausal women (median age 57 years) who were examined by 24-hour ECG monitoring, measurement of arterial pressure, body mass index, and the relationship between waist and hip circumferences. CR disturbances were revealed in all 159 women with abdominal obesity, ischemia in 16.9%, supraventricular extrasystole in 89.3%, ventricular extrasystole (VE) in 58.5%, high-grade extrasystole in 23.9%, paroxysms of supraventricular tachycardia in 1.9%, periods of asystole in 1.3%, synoatrial and atrioventricular blockade in 9.9%, His bundle branch block in 3.3%, sinus tachycardia in 48.8%, and sinus brachycardia in 23.9% of the patients. The risk of development of VE in the women with AO increased by 3.8 times in the presence of concomitant coronary heart disease and by 2.9 times in case of chronic cardiac failure. The frequency of VE was significantly higher in the patients with abdominal obesity than without it (odds ratio 2.2). It is concluded that women presenting with abdominal obesity during the postmenopausal period are characterized by the high frequency of cardiac rhythm disturbances and ischemia, with each fourth patient being at high risk of sudden death. The elevated risk of ventricular extrasystole in the postmenopausal period is associated with AO, coronary heart disease, and chronic heart failure. The frequency of VE is unrelated to ulcer disease, chronic cholecystitis, cholelithiasis, chronic pancreatitis, and impaired function of the thyroid gland.  相似文献   
82.
BACKGROUND AND SIGNIFICANCE: Treatment of multidrug-resistant tuberculosis (MDR-TB) is challenging because of the toxicity of second-line medications. Little is known about whether adverse events impact treatment outcome. METHODS: We conducted a retrospective case series of 244 MDR-TB patients enrolled in Tomsk between 10 September 2000 and 10 September 2002. Adverse reactions were determined by laboratory data and/or clinical criteria. A multiple logistic regression model was performed to determine whether the occurrence of adverse reactions was associated with poor treatment outcome. RESULTS: In this cohort, 76.0% were cured, 6.6% failed, 4.9% died and 11.5% defaulted. Adverse events were observed in 73.3% of patients, occurring in 74.8% of patients who were adherent (taking at least 80% of prescribed doses) and 59.1% of non-adherent individuals (P = 0.11). The impact of adverse events on outcome was modified by non-adherence; among adherent patients, the occurrence of any adverse reaction was associated with treatment cure (adjusted odds ratio 3.24, 95% confidence interval 1.56-6.70). CONCLUSION: Adverse reactions occurred frequently in MDR-TB patients in Tomsk, Russia, but did not negatively impact treatment outcome. The occurrence of adverse reactions among adherent patients was associated with treatment cure.  相似文献   
83.
SETTING: Multidrug-resistant tuberculosis (MDR-TB) is a major problem in countries of the former Soviet Union in both the civilian and prison sectors. OBJECTIVE: To evaluate outcomes of the MDR-TB treatment program (DOTS-Plus) in Tomsk, Russia. DESIGN: Retrospective case series of all patients enrolled in this program between 10 September 2000 and 10 September 2002. The program involves both the civilian and penitentiary TB services in Tomsk. Poor treatment outcome was defined as death, default and treatment failure. RESULTS: Among the 244 patients who received treatment, 77% were cured, 5% died, 7% failed, and 12% defaulted. In a multivariable analysis, alcohol consumption during treatment and the presence of both cavitary and bilateral disease were found to be the strongest predictors of poor treatment outcome. CONCLUSIONS: The integration of civilian and penitentiary TB services in the Tomsk MDR-TB treatment program has resulted in high cure rates and low rates of default. However, alcohol use among patients with MDR-TB is associated with poor treatment outcomes. Better understanding and programmatic alcohol interventions are needed if large-scale treatment of MDR-TB is to be successful in areas with high rates of alcohol use disorders.  相似文献   
84.
Complex molecular architecture of beet yellows virus particles   总被引:2,自引:0,他引:2       下载免费PDF全文
Closteroviruses possess exceptionally long filamentous virus particles that mediate protection and active transport of the genomic RNA within infected plants. These virions are composed of a long “body” and short “tail” whose principal components are the major and minor capsid proteins, respectively. Here we use biochemical, genetic, and ultrastructural analyses to dissect the molecular composition and architecture of particles of beet yellows virus, a closterovirus. We demonstrate that the virion tails encapsidate the 5′-terminal, ≈650-nt-long, part of the viral RNA. In addition to the minor capsid protein, the viral Hsp70-homolog, 64-kDa protein, and 20-kDa protein are also incorporated into the virion tail. Atomic force microscopy of virions revealed that the tail possesses a striking, segmented morphology with the tip segment probably being built of 20-kDa protein. The unexpectedly complex structure of closterovirus virions has important mechanistic and functional implications that may also apply to other virus families.  相似文献   
85.
BACKGROUND: Before 1987, fewer than 50 patients per year at the authors' laboratory had a positive antibody detection test due to antepartum Rhesus immunoprophylaxis. However, after 1987, a marked increase was observed in the number of patients who had received Rh immune globulin (RhIG) during pregnancy as part of routine antepartum Rh immunoprophylaxis. In anticipation that an increased use of RhIG during pregnancy would increase the number of patients in whom anti-D was detected by this laboratory, a protocol was developed to abbreviate the process required to identify anti-D. Although this protocol was adopted primarily to address an anticipated increase in antenatal RhIG usage in women, it was also applied to alloimmunized Rh-negative males. STUDY DESIGN AND METHODS: When an Rh-negative patient (male or female) had a reactive screening test for unexpected antibodies and met certain other criteria, the patient's serum was tested with a three-vial set of Rh-negative reagent red cells (Rh-negative screening RBCs), instead of with panels of typed RBCs (panel RBCs), for the identification of anti- D or the detection of non-D antibodies. If the serum under test did not agglutinate or hemolyze Rh-negative screening RBCs, anti-D was identified and no further testing was performed. If the serum agglutinated or hemolyzed Rh-negative screening RBCs, conventional testing with panel RBCs was done to determine the antibody specificity. RESULTS: Rh-negative patients (n = 1174) who had reactive screening tests for unexpected antibodies were tested with Rh-negative screening RBCs; 1079 were found to have anti-D as a single antibody. Seven of these patients subsequently developed a non-D alloantibody, after transfusion or pregnancy, and one patient had anti-C that escaped detection at the time of initial testing with Rh-negative RBCs (a false- negative result). Ninety-two patients had anti-D in combination with a non-D antibody, and three patients had a non-D antibody but not anti-D. Use of the anti-D identification protocol actually reduced the laboratory workload by 176 College of American Pathologists workload units per month, in spite of a marked increase in the number of patients in whom anti-D was detected. No hemolytic transfusion reaction was attributed to the abbreviation of anti-D identification. CONCLUSION: The identification of anti-D may be abbreviated without jeopardizing patient safety. Such a protocol can reduce laboratory workload and might be particularly appealing to health care facilities that perform antibody detection testing on large numbers of Rh-negative pregnant women, especially if antepartum RhIG is administered routinely.  相似文献   
86.
A crystallization method was proposed to assess disturbances in the lipid system; it was based on the interaction of a serum lipid fraction with a lecithin matrix. A total of 255 invidividuals were examined. A model experiment was performed by using chemically pure cholesterol (96 samples) and 10 different cholesterol esters (240 samples). There were a great differences in the frequency of various pattern structural types (homogeneous texture, fan crystals) in the healthy persons and patients. The test results were found to be related to the ratio of esterified to non-esterified cholesterol in the serum lipid fraction. The application of rheopolyglucin, , hemosorption, quantum hemotherapy in the patients contributed to normalization of crystallization test indices.  相似文献   
87.
Reilly  IA; FitzGerald  GA 《Blood》1987,69(1):180-186
The capacity of platelets to generate thromboxane A2, reflected by measurement of serum thromboxane B2 (TxB2), greatly exceeds the systemic production of thromboxane in vivo. Thus, it is possible that substantial but incomplete inhibition of thromboxane formation ex vivo would still allow marked augmentation of thromboxane production in vivo. To address this hypothesis, we administered aspirin 120 mg, a selective inhibitor of thromboxane synthase (TxSl), 3-(1H-imidazol-1-yl- methyl)-2-methyl-1H-indole-1-propanoic acid (UK-38, 485) 200 mg, and a combination of both drugs to 12 healthy volunteers and measured the effects on serum TxB2 and urinary 2,3-dinor-thromboxane B2 (Tx-M), an index of endogenous thromboxane biosynthesis. Although serum TxB2 was maximally inhibited by 94 +/- 1% after aspirin and 96 +/- 2% after the TxSl, maximal depression of Tx-M was only 28 +/- 8% and 37 +/- 9%, respectively. Combination of aspirin with the TxSl resulted in a small but significant increase in inhibition of thromboxane generation ex vivo (98 +/- 1% v 94 +/- 1%; P less than 0.05), but a disproportionately greater fall in thromboxane synthesis in vivo (58 +/- 7%; P less than 0.01). Consistent with further inhibition of platelet thromboxane synthesis, addition of the TxSl abolished the transient decline in prostacyclin formation after aspirin alone. Administration of a lower dose of aspirin (20 mg) to 6 healthy subjects caused a small reduction in Tx-M (12 +/- 4%; P less than 0.05) and inhibited serum TxB2 by 48 +/- 2%. The relationship between inhibition of platelet capacity to form thromboxane ex vivo (serum TxB2) and synthesis in vivo (Tx-M) departed markedly from the line of identity. When total blockade of the capacity of platelets to generate thromboxane is approached, minor decrements in capacity result in a disproportionate depression of actual thromboxane biosynthesis. These results imply that pharmacologic inhibition of serum TxB2 must be virtually complete before thromboxane- dependent platelet activation is influenced in vivo.  相似文献   
88.
BACKGROUND: Hospitals and blood centers throughout the United States use a variety of reagents and methods to perform pretransfusion testing. A survey was developed to determine the reagents and methods in use and their relative prevalence in different work settings. STUDY DESIGN AND METHODS: A national survey on pretransfusion testing was conducted. Surveys were distributed to state and regional blood bank associations, which then distributed them to hospitals and blood centers within their region. In most instances, the blood centers distributed the survey to the local hospitals. Completed surveys were returned to the authors for review, and all information was entered into a database for analysis. RESULTS: Analysis of the data shows that the majority of blood banks use monoclonal reagents for ABO testing and monoclonal-polyclonal blended reagents for Rh testing. The data show that anti-IgG and polyclonal antihuman globulin reagents are used almost equally for antibody screening (detection) tests and that most blood banks use a three-cell antibody-screening test. Slightly more than 50 percent of hospitals use an immediate-spin crossmatch in the absence of unexpected antibodies. CONCLUSION: A number of approved reagents and methods are used by blood bank laboratories for pretransfusion testing. Facility size (number of beds) and type tend to influence the choice of methods and reagents employed. This survey provides an opportunity for blood bank laboratories to compare their current practices with those of their peers.  相似文献   
89.
90.
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