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The purpose of the study was to investigate potential associations between tumour necrosis factor (TNF), soluble TNF receptors (sTNF-Rs), immunoglobulin (Ig)G subclasses and development of cytomegalovirus (CMV) disease amongst human immunodeficiency virus (HIV)-1 patients. We enrolled HIV-1 patients with CD4 counts less than 100/μl in a prospective study and followed them over 1 year for development of CMV disease. Concentrations of TNF, sTNF-RI, sTNF-RII and IgG subclass reactivities were measured by ELISA; levels of CMV pp65 antigenaemia were determined as numbers of pp65 expressing cells/100 000 cells and were measured by staining of leucocytes; and HIV-1 RNA loads were measured by polymerase chain reaction (PCR). Eighteen patients studied with CMV disease had higher levels of sTNF-RI than 18 similar patients without CMV disease. Concentrations of sTNF-RI correlated with levels of CMV antigenaemia in blood samples collected before the development of CMV disease. Patients with CMV disease had lower levels of IgG1 reactivities to CMV than patients without CMV disease. We conclude that increased levels of sTNF-RI and decreased IgG1 reactivities are associated with an increased risk of development of CMV disease among HIV-1 patients.  相似文献   
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OBJECTIVE: To determine whether adenosine instead of supranormal potassium in cold crystalloid cardioplegia gives satisfactory cardiac arrest and improved cardioprotection. Cold crystalloid cardioplegia with adenosine, procaine and magnesium (A) was compared with standard cold crystalloid hyperkalemic cardioplegia (K). METHODS: Sixteen pigs were randomized to receive either cold K (n=8) or A (n=8), where hyperkalemia was substituted with 1.2 mM adenosine. The cold (6 degrees C) cardioplegia was given intermittently and antegradely, with an aortic cross-clamp time of 1 h. Hemodynamic data was continuously measured and pressure-volume conductance catheters were used to determine global left ventricular systolic and diastolic function. Coronary flow and O2 content differences allowed determination of left ventricular energetics. Blood samples, and left ventricular microdialysis were used to measure parameters of ischemia. Measurements were done at 1 and 2 h after cross-clamp release. RESULTS: Mean arterial pressure was reduced with 55 mmHg (standard deviation, SD: 19) in the K group versus 30 mmHg (SD: 14) in the A group 2 h after cross-clamp release (p=0.030). Left ventricular contractility expressed as slope of the preload recruitable stroke work index (Mw) was reduced to 53% (SD: 14) in the K group versus 78% (SD: 23) in the A group 2h after cross-clamp release (p=0.046). Reduction of maximum of first derivate of pressure with respect to time (dP/dtmax) was 804 mmHg/s (SD: 189) in the K group versus 538 mmHg/s (SD: 184) in the A group (p=0.033). The slope of the myocardial oxygen consumption-pressure volume area was at 2 h reperfusion increased from 1.37 (SD: 0.64) to 2.86 (SD: 1.27) in the K group, whereas no shift was detected in the A group (p=0.019). Cardiac troponin T measured in the coronary sinus 1 h after cross-clamp release was 1.25 microg/l (SD: 0.64) in the K group versus 0.73 microg/l (SD: 0.31) in the A group (p=0.046). CONCLUSION: Adenosine instead of supranormal potassium in cold crystalloid cardioplegia gives satisfactory cardiac arrest, improves post cardioplegic left ventricular systolic function and efficiency, and attenuates myocardial cell damage.  相似文献   
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The brains of rats with streptozocin-induced diabetes treated with a low-dose insulin regimen (1 IU/day) were studied with morphometric techniques. After 1 yr of diabetes, brain weight decreased slightly (1350 +/- 71 vs. 1521 +/- 55 mg, 2P less than .01) as did the volume of the neocortex (498 +/- 36 vs. 567 +/- 40 mm3, 2P less than .05). A significant loss of neocortical neurons occurred (38 +/- 2 X 10(6) vs. 46 +/- 3 X 10(6), 2P less than .01), and the length of the capillary network in the neocortical tissue shortened disproportionately (405 +/- 102 vs. 631 +/- 47 m, 2P less than .01), leading to increased diffusion distance. The mechanisms underlying cerebral loss in this model are unknown, but abnormalities of the vascular supply with prolongation of the route of diffusion might play a role.  相似文献   
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In a pilot study of 6 patients with subarachnoid hemorrhage caused by a ruptured intracranial (grade IV (Hunt and Hess) aneurysm the hemodynamics and plasma-nimodipine concentrations have been observed during a 3-week period of treatment. We found that 3 patients developed reversible hypotension during the nimodipine treatment and that the hypotension tendency could be related to the plasmanimodipine level and not to a more or less severe sensitivity to nimodipine.

Repeated measurements of blood pressure, plasma-nimodipine and regional cerebral blood flow (rCBF) are necessary for the purpose of obtaining the optimum treatment and for evaluating the effect of treatment.  相似文献   

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The retinoids are a class of compounds that includes the natural forms and synthetic analogues of vitamin A. Isotretinoin, often referred to as a first generation retinoid, may be of considerable benefit to patients with severe, recalcitrant acne. Etretinate and acitretin, 2 aromatic compounds representing the second generation, have found their major success in the treatment of psoriasis, particularly in combination with more traditional therapies. Retinoid therapy is associated with a distinctive adverse effect profile typical of hypervitaminosis A; thus, it is especially important that fertile women undergoing retinoid therapy adhere to a contraceptive regimen. These drugs are extensively metabolised and only traces of unchanged drugs are eliminated in urine. The terminal elimination half-lives of isotretinoin, etretinate and acitretin after long term treatment are up to 20h, 120 days and 48h, respectively. Because of lack of definite correlation between plasma concentration and desired pharmacological effects, in conjunction with the very pronounced inter- and intraindividual variation in systemic availability (15 to 90%) after oral administration of these drugs, initial dosages in individual patients can only be roughly judged on the basis of the general pharmacokinetics of the agents. Later dosage adjustments should be made on the basis of monitoring of both plasma drug (and possible metabolite) concentrations, and the efficacy and tolerability of the drugs.  相似文献   
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A paleopathological maxilla and mandible with tooth agenesis were analyzed, focussing on the aetiology of the condition. The jaw material, derived from an adult mediaeval male, was examined by standard anthropological analyses, including radiography. In the maxilla there was agenesis of three permanent incisors and one premolar, and in the mandible of one permanent incisor and two permanent molars. Absence or marked reduction of the incisive foramen and the nasopalatine canal was found. The pattern of tooth agenesis was similar to the pattern observed in contemporary individuals, except for the agenesis of one permanent maxillary centreal insisor. It is suggested that the pronounced lack of the premaxillary area of the nasopalatine canals and the incisive foramen. As the condition can be ascribed to deviations in the prenatal developments, this investigation shows that embryological developmental patterns, which form the basis for the pattern of tooth agenesis, should be taken into account when evaluation dry bonde patholgy.  相似文献   
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