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41.
When initiating monotherapy for the treatment of essential hypertension, multiple determinants factor into the decision. The goal of treatment is to lower blood pressure and lessen the likelihood of progression to target organ failure. Physicians frequently prioritize these determinants and make decisions to initiate monotherapy based on the race of an individual. All too often, however, the black/white issue is overstated and given too much consideration. The overall goal of this review is to suggest the appropriate "role" for racial profiling in the initial selection of an antihypertensive agent.  相似文献   
42.
Chronic pelvic pain in the absence of organic pathology identifiable in medical terms is considered one of the most perplexing conditions that gynecologists confront. A critical analysis of the medical, psychiatric, and psychological literature on chronic pelvic pain without organic pathology reveals that the dichotomous construct of mind and body underpinning medical research and understanding is a barrier to the successful diagnosis and treatment of this condition, and indeed to the productive engagement of the health professional with the patient. The strict duality of the condition's etiology being understood in either physiological or psychogenic terms has been questioned at times over the last 40 years, but only recently has an "integrative model" been proposed. However, it is argued here that although the development of a multidisciplinary approach is important, only a radical deconstruction of the medical paradigm will truly address the problem and enable a real change in practice.  相似文献   
43.
The aim of the study was TPS diagnostic value determination in the serum of women with breast cancer as compared with MCA and CA 15-3. The relationship between the serum concentration of these antigens and patient age, clinical stage, histological grade, presence of metastases to lymph nodes and histological type of neoplasm was evaluated. Studies were conducted on the sera of 139 women before surgical procedure aged 28-81, treated in the Clinic of Oncology, at Karol Marcinkowski University of Medical Sciences in Poznań. The TPS concentration was determined using the "BEKI Diagnostics" immunoenzymatic method, MCA - by the "Roche" test and CA 15-3 concentration was determined by the "Abbott" immunofluorescent test. The study showed significantly higher levels of TPS, CA 15-3 and MCA in women with cancer, compared with values in healthy women and women with mastopathy. The highest median of concentration and frequency of occurrence was obtained for TPS. A correlation between enhancement of TPS and CA 15-3 concentration with clinical stage was observed. A similar connection was noted in women with metastases to the lymph nodes. Serum MCA concentration results did not demonstrate the above effects. The study suggests, that in estimating the clinical condition of women with breast cancer, the simultaneous determination of TPS with CA 15-3 seems to be a more useful prognostic factor than TPS or CA 15-3 with MCA.  相似文献   
44.
Personal clinical observations during the recent years allow the authors to confirm the indisputable value of surgical experience got during the Great Patriotic War (1941-1945) and in particular, the "fourfold" scheme proposed by V. I. Voiachek for the diagnosis and treatment of blind gunshot wounds to the skull base. Computed tomography considerably increases the probability of detection of the exact localization of foreign bodies in complex anatomical structures of the skull and thus facilitates choosing the most rational surgical management. The use of the electro-optical transducer for the extraction of foreign bodies from almost inaccessible areas of the skull base decreases the risk of operation.  相似文献   
45.
During a six-month period 2,221 haemocultures obtained from patients hospitalized in the Faculty Hospital Olomouc were examined. In all 304 isolated bacteria the sensitivity was assessed by the standard dilution micromethod and moreover all positive haemocultures were examined the "direct" disc method. Agreement between the results of the two methods was proved in 84% of pairs of tests and within a range from 67 to 100%, depending on the type of antimicrobial preparation. Based on these findings it may be stated that assessment of the sensitivity by the "direct" method agrees significantly with assessment of the sensitivity according to minimal inhibitory concentrations (MIC). In patients with septicaemia this procedure makes it possible to change empirical antibiotherapy by 24 hours sooner to aimed therapy.  相似文献   
46.
OBJECTIVES: To i) document the sensitivity and specificity of a combined scintigraphic/lactulose breath hydrogen test for small intestinal bacterial overgrowth and ii) investigate the validity of currently accepted definitions of an abnormal lactulose breath hydrogen test based on "double peaks" in breath hydrogen concentrations. METHODS: Twenty-eight subjects were investigated with culture of proximal small intestinal aspirate and a 10-g lactulose breath hydrogen test combined with scintigraphy. Gastroduodenal pH, the presence or absence of gastric bacterial overgrowth, and the in vitro capability of overgrowth flora to ferment lactulose were determined. RESULTS: Sensitivity (16.7%) and specificity (70.0%) of the lactulose breath hydrogen test alone for small intestinal bacterial overgrowth were poor. Combination with scintigraphy resulted in 100% specificity, because double peaks in serial breath hydrogen concentrations may occur as a result of lactulose fermentation by cecal bacteria. Sensitivity increased to 38.9% with scintigraphy, because a single rise in breath hydrogen concentrations, commencing before the test meal reaches the cecum, may occur in this disorder. Sensitivity remained suboptimal irrespective of the definition of small intestinal bacterial overgrowth used, the nature of the overgrowth flora, favorable luminal pH, the presence of concurrent gastric bacterial overgrowth, or the in vitro ability of the overgrowth flora to ferment lactulose. CONCLUSIONS: Definitions of an abnormal lactulose breath hydrogen test based on the occurrence of double peaks in breath hydrogen concentrations are inappropriate. Not even the addition of scintigraphy renders this test a clinically useful alternative to culture of aspirate for diagnosing small intestinal bacterial overgrowth.  相似文献   
47.
Angiotensin II (A II) and analogues were tested for their ability to restore electrical and mechanical activity to cardiac muscle preparations in which the fast Na+ channels had been inactivated by partial depolarization (22-27 mM K+) or by tetrodotoxin (TTX). The partially depolarized or TTX-blocked preparations were chosen because under these conditions electrical and mechanical responses are primarily Ca2+ -dependent. In depolarized rabbit right atria, A II restored spontaneous mechanical and electrical activity (measured by both intracellular and extracellular recording techniques). The frequency of action potential discharge was concentration-dependent; the threshold concentration of A II was 10(-10) M, the ED50 was 8 X 10(-9) M, and the maximum effect was observed at 5 X 10(-8) M. In contrast, depolarized guinea pig atria were insensitive to A II, Sar1-angiotensin II, and des-Asp1-angiotensin II, even at concentrations as high as 10(-5) M. Rabbit papillary muscle (TTX-blocked), embryonic (18-day) chick heart (partially depolarized) and chick heart reaggregates (TTX-blocked) responded similarly to rabbit atria in that A II (9.6 X 10(-7) M) restored both electrical and mechanical activity. We found that in these preparations the action of A II was unaffected by propranolol (5.0 X 10(-6) M to 5.0 X 10(-5) M) but was blocked by Mn2+ (10(-3) M), D-600 (1 X 10(-7) g/ml) and the specific A II antagonists Sar1-Ala8-angiotensin II (P-113) (5.0 X 10(-5) M) and Sar1-Ile8-angiotensin II (5.28 X 10(-5) M). We conclude that the positive inotropic effect of A II on the myocardium is due to its ability to increase transmembrane ion movements in or through the cell membrane. The ability of Mn2+ and D-600 to block this effect suggests that this ion movement is via the so-called "slow channels."  相似文献   
48.
Metal–oxide–semiconductor (MOS) capacitors based on HfO2 gate stacks with Al and TiN gates are compared to study the effect of the gate electrode material to the properties of insulator–semiconductor interface. The structures under study were shown to contain interface trap densities of around 2 × 1011 cm−2 eV−1 for Al gate and up to 5.5 × 1012 cm−2 eV−1 for TiN gate. The peak in the surface state distribution was found at 0.19 eV above the valence band edge for Al electrode. The respective capture cross-section is 6 × 10−17 cm2 at 200 K.The charge injection experiments have revealed the presence of hole traps inside the dielectric layer. The Al-gate structure contains traps with effective capture cross-section of 1 × 10−20 cm2, and there are two types of traps in the TiN-gate structure with cross-sections of 3.5 × 10−19 and 1 × 10−20 cm2. Trap concentration in the structure with Al electrode was considerably lower than in the structure with TiN electrode.  相似文献   
49.
Experiments on rats demonstrated that the low-intensity electromagnetic field (12.6 cm, 2375 MHz, power density 1 mW/cm2), motion sickness, and electroconvulsive shock provoked the retrograde amnesia in the passive avoidance test. The oxyracetam (100 mg/kg, i.p.), aniracetam (50 mg/kg, i.p.), nooglutil (50 mg/kg, i.p.), meclofenoxate (50 mg/kg, i.p.), pyracetam (200 mg/kg, i.p.), and GABA (200 mg/kg, i.p) prevented the memory-impairing effect of all these extreme factors. On the contrary, the N-acetylglycinamide, semax, and other nootropic drugs were effective only under one or two extreme conditions.  相似文献   
50.
The precise measurement of low numbers of leukocyte below 0.1 WBC/microliter in filtered red cell or platelet suspensions meet both aims: to check the compliance with previously determined requirements and to evaluate the performances of novel filtering material (5 log depletion or more), justified by more and more important clinical use. The reliability of results, obtained with the chosen method, is ensured by applying of validation protocol, including training of technologist, assessment of the analytical range and the detection limit, assessment of precision and accuracy. The flow cytometry (FC) and Nageotte Chamber (NC) method are the both techniques which are currently used in routine Quality Control (QC) and validated by multicenter studies. Recent developments are made for increasing the sensibility of these counting methods, thanks to higher concentration or volume of the sample to be analysed. Among the experimental techniques, requiring more advances before implementing in QC program, quantitative PCR must become essential as reference method for evaluating the efficiency of filtration, in the future.  相似文献   
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