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71.
Access site complications occur in 5-15% of cases according to the various series. The predictive factors most often reported in the literature are the size of the puncture site and the intensity of the antiplatelet or anticoagulant treatment associated with the angioplasty procedure. Six senior cardiologists in a high volume Cardiology center (>1,500 procedures a year) with an individual experience >500 procedures in either the radial approach or the percutaneous suture of the femoral artery with the Techstar/Prostar system, conducted a prospective study from January 1 to December 31, 1999. The aim of this study was to eliminate the occurrence of access site complications by using either one of two techniques that were at the operator's discretion, i.e., systematic radial approach, or percutaneous suture of the femoral artery. A total of 956 patients were included over the study period; 60.7% of these patients had percutaneous arterial closure of the femoral artery and the remaining 39.3% were treated via the radial approach; 88.7% were stented. The patients were administered a mean 9,000 IU of heparin during the procedure; 1.9% had been fibrinolyzed and Reopro was used in 5.9%. No complications were documented in the radial group. Of the 580 patients in the femoral suture group, 96.9% had femoral suture, immediately effective in 508 cases (90.4%). Only 3 patients required additional prolonged compression. One significant hematoma (0.2%) necessitating blood transfusion was reported in the femoral group. Infection at the puncture site with subsequent antibiotic treatment was reported in 2 patients (0.3%). No further access site complications were observed at one-month follow-up. After completion of the learning curve, the two techniques (radial approach and percutaneous arterial suture) permit the almost total elimination of access site complications.  相似文献   
72.
73.
Atrial natriuretic peptide, altitude and acute mountain sickness   总被引:5,自引:0,他引:5  
1. To investigate the mechanisms of acute mountain sickness, 22 subjects travelled to 3100 m by road and the following day walked to 4300 m on Mount Kenya. Control measurements were made over 2 days at 1300 m before ascent and for 2 days after arrival at 4300 m. These included body weight, 24 h urine volume, 24 h sodium and potassium excretion, blood haemoglobin, packed cell volume, and symptom score for acute mountain sickness. In 15 subjects blood samples were taken for assay of plasma aldosterone and atrial natriuretic peptide. 2. Altitude and the exercise in ascent resulted in a marked decrease in 24 h urine volume and sodium excretion. Aldosterone levels were elevated on the first day and atrial natriuretic peptide levels were higher on both altitude days compared with control. 3. Acute mountain sickness symptom scores showed a significant negative correlation with 24 h urinary sodium excretion on the first altitude day. Aldosterone levels tended to be lowest in subjects with low symptom scores and higher sodium excretion. No correlation was found between changes in haemoglobin concentration, packed cell volume, 24 h urine volume or body weight and acute mountain sickness symptom score. 4. Atrial natriuretic peptide levels at low altitude showed a significant inverse correlation with acute mountain sickness symptom scores on ascent.  相似文献   
74.
According to the dopamine (DA) hypothesis of schizophrenia and the strong evidence for decreased cerebral lateralization in schizophrenic patients, we postulated that hyperactivity of the dopaminergic system could be associated with a reduced behavioral lateralization in mice. Mice lacking the dopamine transporter (DAT) gene were used as a genetic model of persistent hyperdopaminergia. The DAT null mutation was transferred on C57BL/6JOrl (B6) and DBA/2JOrl (D2) inbred backgrounds for more than 10 generations of backcrossing to derive three DAT strains, B6, D2, and B6xD2(F1). Adult mutant mice of the three DAT strains and their littermates were tested for paw preference using Collins' protocol. Our results demonstrated that, whatever the genetic background, persistent hyperdopaminergia directly impairs the degree of lateralization without affecting the direction. Our results support the degree of lateralization as a good candidate phenotype to further improve genetic analysis of cerebral lateralization in normal and pathological conditions.  相似文献   
75.
76.
Cancer is the second cause of death in women under 40 years of age in Western Europe and the United States. Survival after cancer treatment has improved during the past three decades. In line with this, procedures have been developed to optimize the quality of life, in particular the development of fertility-enhancing and fertility-preservation techniques. Surgery, chemotherapy and radiotherapy affect the fertility potential of women in different ways and to different degrees. Surgery has a direct impact by removing the uterus and ovaries. Radiotherapy (external or brachytherapy) may affect ovarian and also uterine function. Different drugs used in chemotherapy may directly influence ovarian function. Some markers have now been evaluated that are predictive of the potential toxic injury to the gonads and uterus. Various procedures could be proposed to preserve fertility potential in women, before delivering anticancer treatments or after treating the tumor. However, such treatments can only be considered if they do not have deleterious consequences on the survival of patients. As well as the preservation of fertility, there is the issue of contraception; and in the case of impaired ovarian function, the issue of a substitute hormonal treatment.  相似文献   
77.
The authors present the radiographic features of a previously incompletely delineated bone dysplasia, which they call spondylometaphyseal dysplasia, corner fracture type. This is a dominant heritable condition associated with short stature and developmental coxa vara. The progressive hip deformity usually causes significant disability requiring surgical correction. Developmental coxa vara, simulated corner fractures of long tubular bones, and vertebral body abnormalities result in a diagnostic constellation. Knowledge of these distinctive radiologic features allows accurate diagnosis, which in turn should lead to appropriate genetic counseling and possibly to earlier, more efficacious surgical treatment of the coxa vara.  相似文献   
78.
M S Ewer  M K Ali  M S Atta  R C Morice  P V Balakrishnan 《JAMA》1986,256(24):3364-3366
The prognosis of lung cancer patients who are not candidates for surgery is usually poor. The unfavorable natural history of respiratory failure in this group of patients has been suggested as a causative factor. We analyzed the outcome of 46 consecutive patients with primary lung cancer on whom mechanical ventilators were utilized. Although seven patients were ultimately weaned and survived for at least 24 hours, three of them subsequently died prior to discharge from the hospital. The remaining 39 patients died while using the ventilator. Patient age, tumor cell type, and the etiology of respiratory failure were not significantly different between the weaned and unweaned populations. A difference was noted in the duration of mechanical ventilation: none of the patients who could be weaned required mechanical ventilation for more than six days (range, two to six days). Respiratory failure in the nonsurgical lung cancer patient carries a poor prognosis, and selection of patients for mechanical ventilation should be conservative.  相似文献   
79.
The panel considered the different types of cough in terms of basic mechanisms and clinical manifestations; both experimentally and clinically cough could occur in single efforts and as ‘bouts’ or ‘epochs’. There were different definitions of cough but, provided the definition used was clear, this did not seem to be a major concern.The methods available for determining the nature or type of clinical cough were discussed, in particular automated cough counting in the clinic and more sophisticated methods available in the laboratory.With regard to semantics, there has been great variation in the names used; this applies to nervous sensors for cough, to cough reflexes and epochs, to clinical names for cough, and to cough sounds. Some simplification and uniformity of nomenclature seemed desirable although, provided the use of a name was clear, little confusion probably existed. The panel felt that the cough nomenclature would evolve with time and would prove to be useful for investigators, clinicians and coughers.  相似文献   
80.
Three examples of human plasma-derived concentrates, intermediate- purity factors VIII and IX, and fibrinogen were spiked with tissue culture-grown human immunodeficiency virus type 1 (HIV-1) strain RF. All examples were freeze-dried and heated at 80 degrees C for 72 hours by using validated production process models. HIV-1 infectivity was measured by a syncytial infectivity assay in C8166 cells and then compared with levels determined by nested HIV polymerase chain reaction (PCR). The infectivity assay demonstrated a reduction index of at least 4.5 log10, while PCR showed an average 1.7 log10. Large amounts of HIV- 1 RNA (10(5)) were still detectable by PCR in samples in which infectivity assays failed to detect any HIV-1. These data suggest that HIV-1 PCR levels do not parallel HIV-1 infectivity levels during virus- inactivation procedures involved in coagulation factor concentrate production. PCR was able to detect the RNA associated with inactivated HIV-1 particles in the factor concentrates, which allows the conclusion that PCR is not a useful test with which to monitor virus-inactivation procedures such as heating at 80 degrees C for 72 hours. This judgment contrasts with the more definite and sensitive role of PCR in diagnosing HIV-1 infection in patients in whom a positive HIV-1 PCR result correlates with active HIV-1 infection and with PCR's usefulness in monitoring virus removal.  相似文献   
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