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Study Objective . To determine if one commercial extended-release formulation of nifedipine (Adalat CC) is as effective as another (Procardia XL) in controlling blood pressure over 24 hours. Design . Open-label, randomized, crossover study. Setting . University-affiliated family medicine clinic. Patients . Fifteen patients with stage 1–4 primary hypertension. Interventions . Procardia XL or Adalat CC once/day was titrated to achieve blood pressure control. The effective dose was continued for 4 weeks, washed out for 1 week, and reinstituted with other study drug. Measurements and Main Results . Twenty-four-hour ambulatory blood pressure was recorded the conclusion of each treatment phase. Treatment phases were compared for mean 24-hour blood pressure, mean daytime (6:00 a.m.–10:00 p.m.) and mean nighttime blood pressure, and mean blood pressure load (percentage of blood pressure measurements < 140/90 mm Hg daytime and > 120/80 mm Hg nighttime). Thirteen patients completed the study. No statistically significant difference was seen in mean 24-hour blood pressure (138/86 mm Hg for Procardia XL vs 137/85 mm Hg for Adalat CC), daytime or nighttime blood pressure, or blood pressure load. Two patients experienced clinically significant adverse effects while taking Adalat CC. Conclusions . In these patients with primary hypertension, Adalat CC was as effective as Procardia XL at controlling blood pressure for 24 hours. Blood pressure, heart rate, and adverse effects should be monitored 2–4 weeks after any exchange of Adalat CC for Procardia XL.  相似文献   
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OBJECTIVE: To assess the extent of nosocomial transmission of tuberculosis among infants, family members, and healthcare workers (HCWs) who were exposed to a 29-week-old premature infant with congenital tuberculosis, diagnosed at 102 days of age. DESIGN: A prospective exposure investigation using tuberculin skin test (IST conversion was conducted. Contacts underwent two skin tests 10 to 12 weeks apart. Clinical examination and chest radiographs were performed to rule out disease. Isoniazid prophylaxis was administered to exposed infants at higher risk. SETTING: A neonatal intensive care unit in an urban hospital in Brussels, Belgium. PARTICIPANTS: Ninety-seven infants, 139 HCWs, and 180 visitors. RESULTS: Newly positive TST results occurred in HCWs who had been in close contact with the infant. Six (19%) of 32 primary care nurses and physicians had TST conversions and received treatment. Among the 97 exposed infants, 85 were screened and 34 were identified as at higher risk of infection. Of these, 27 received preventive isoniazid. None of the infants and none of the 93 other infants' family members evaluated were infected. CONCLUSIONS: Congenital tuberculosis in an infant poses a risk for nosocomial transmission to HCWs. Delayed diagnosis of this rare disease and close proximity are the most important factors related to transmission.  相似文献   
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Experimental allergic encephalomyelitis (EAE) is an autoimmune inflammatory disease of the central nervous system (CNS). In particular in the CsA-induced chronic relapsing form (CREAE), pronounced demyelination occurs, in temporal association with relapses. It is still a matter of discussion which cell type ultimately is responsible for the actual process of demyelination. Macrophages, cytotoxic T lymphocytes and also astrocytes are possible candidates. In this short overview, the role of macrophages in the pathogenesis of EAE is discussed. It is shown that in particular, newly recruited macrophages play a crucial role in the generation of clinical signs. Possible mechanisms by which macrophages are involved in the pathogenesis of demyelinating diseases are presented.  相似文献   
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Day-to-day variations in serum iron, serum iron binding capacity, serum ferritin and erythrocyte protoporphyrin were determined on 2 successive days in 48 patients with anaemia. The correlation coefficients between the paired determinations were 0.86, 0.89, 0.95 and 0.95, and the day-to-day coefficients of variation (in per cent) were 33, 11, 12 and 13 for serum iron, serum iron binding capacity, erythrocyte protoporphyrin and serum ferritin, respectively. Thus, in patients with anaemia, day-to-day variations in serum iron, serum iron binding capacity, erythrocyte protoporphyrin and serum ferritin are at least as high as in healthy controls. The results indicate important limitations in the use, particularly, of serum iron in the clinical investigation of anaemia.  相似文献   
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OBJECTIVE We studied the relationship between plasma level of insulin-like growth hormone I (IGF-I), changes in lean body mass and in adipose mass, and adverse side-effects during human growth hormone (hGH) treatment of elderly men who had low IGF-I levels. DESIGN The first six months was a period of baseline observation. The subjects were then randomized into two groups so that during months 7–18, men in group I received hGH, and men in group II served as untreated controls. SUBJECTS Eighty-three overtly healthy elderly men, who were selected because their plasma IGF-I level was less than 0.35 units/ml. The men were randomly assigned in a ratio of three to one into group I (n= 62) or into group II (n= 21). MEASUREMENTS Plasma IGF-I level was measured monthly. Lean body mass and adipose mass were measured every six months. RESULTS Fifteen men left the study during the baseline period because of personal reasons or intercurrent medical events. In those who received drug (group I), there were a number of adverse reactions which could have been related to the hGH therapy: carpal tunnel syndrome 10, gynaecomastia 4, and hyperglycaemia 3. In total there were 27 dropouts from group I and two dropouts from group II after the six-month point, for a variety of medical and non-medical reasons, the majority probably not related to hGH therapy. During the hGH treatment of group I, plasma IGF-I increased from the range 0.10–0.35 units/ml into the range 0.5–2.2 units/ml. Among the 18 men who completed 12 months of hGH treatment without experiencing one of the three above-noted presumed hGH side-effects, mean and peak plasma IGF-I during treatment were significantly lower than among the 13 men who experienced carpal tunnel syndrome or gynaecomastia (one subject had both) while on hGH. With one exception, neither carpal tunnel syndrome nor gynaecomastia occurred in any individual with a mean IGF-I level less than 10 units/ml during hGH treatment. Twelve months of hGH treatment (group I) caused an increase in lean body mass to 106% of the initial baseline (month one of the protocol), and a reduction in adipose mass to 84% of the baseline. Meanwhile, the lean body mass of the untreated men in group II declined to 97% of the initial baseline. The body composition responses after 12 months of treatment in group I were larger in the men whose mean intra-treatment IGF-I level was 0.5–1.0 units/ ml, than in the men whose mean intra-treatment IGF-I level was 1.0–1.5 units/ml. CONCLUSIONS These observations show that when elderly men with low circulating IGF-I concentrations are treated continuously with hGH, elevation of plasma IGF-I above 10 units/ml is associated with a substantial frequency of carpal tunnel syndrome or gynaecomastia. It may be that the effects of the hormone in expanding lean body mass and reducing adipose mass can be achieved, and the side-effects avoided, by maintaining the mean IGF-I level in the range 0.5–1.0 units/ml.  相似文献   
7.
Background: Liver dysfunction as a result of impaired oxygen availability frequently occurs following hemorrhage and contributes to delayed mortality. Artificial oxygen carriers may improve oxygen supply to vital organs while avoiding the need for allogeneic transfusion.

Methods: Rats were subjected to hemorrhagic hypotension (mean arterial pressure = 35-40 mmHg for 120 min) and were subsequently resuscitated with (1) stored whole rat blood, (2) pentastarch, or (3) pentastarch combined with perflubron emulsion (PFE; 2.7 or 5.4 g/kg body weight), a second-generation artificial oxygen carrier. Recovery of liver adenosine triphosphate, hepatocellular injury, and expression of glutamine synthetase 1, a gene that is induced by exposure of hepatocytes to low partial pressure of oxygen, were studied at 4 h of resuscitation.

Results: Stored whole blood or pentastarch failed to restore liver adenosine triphosphate concentrations after prolonged shock as compared to sham controls and resulted in increased gene expression of glutamine synthetase 1. Addition of 2.7 g PFE/kg restored liver adenosine triphosphate to control, whereas 5.4 g PFE/kg resulted in adenosine triphosphate concentrations significantly above control. Improved hepatocellular oxygen supply was also confirmed by restoration of the physiologic expression pattern of glutamine synthetase 1. Serum enzyme concentrations were highest after resuscitation with stored blood, whereas addition of PFE failed to further decrease enzyme concentrations as compared to pentastarch alone.  相似文献   

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The resorption pattern of synovial fluid through the lymphatic system from normal and synovitic knee joints in rabbits was studied with 99mHechnetium-rhenium-sulfur colloid injected intraarticularly and monitored for 14 hours with a gamma camera.

On the normal side the regional lymph nodes were visualized after I hour and after 14 hours still 75 percent activity remained in the knee. In the synovitic knees no lymphatic transport could be detected; and the radiotracer was unstable with rapid liberation of technetium, which was excreted in the urine. This radiolysis was not found in vitro in synovitic joint fluid.

The lymphatic transport from normal rabbit knees is low. We found a clear difference in lymphatic transport between normal and synovitic knee joints.  相似文献   
10.
We studied vascular endothelial growth factor (VEGF) expression in bone marrow sections obtained from 3 healthy donors and 41 patients with acute myeloid leukemia (AML) of various French-American-British (FAB) subtypes by immunohistochemical analysis using an anti-VEGF antibody. In normal bone marrow, the anti-VEGF antibody reacted with myeloid progenitor cells and megakaryocytes but not with erythroid cells or mature granulocytic cells. High levels of VEGF were found in the bone marrow in patients with AML-M1, -M2, -M3, -M4, -M4Eo, and -M5. In these leukemias, the vast majority of myeloblasts (> 90%) expressed VEGF. By contrast, in AML-M0, the percentage of VEGF-positive blasts was lower in most cases (median, 42%), and if at all detectable, these blast cells contained only trace amounts of VEGF. In AML-M3 and -M4Eo, maturing granulocytes failed to express VEGF similar to granulocytes in normal bone marrow. In AML-M6, myeloblasts exhibited VEGF, whereas erythroid cells did not. In AML-M7, blast cells and megakaryocytes were identified as major sources of VEGF. In summary, VEGF expression in the bone marrow is restricted to certain stages of differentiation and maturation of myeloid cells and correlates with the FAB category.  相似文献   
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