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1.
Haemophagocytic syndrome is a heterogenous disease characterized by disordered macrophage activation associated with viral, bacterial or parasitic infection. The few reports of haemophagocytosis occurring in the presence of mycobacterial infection show a high mortality rate and we present two further cases notable for their favourable issue. Rapidity of diagnosis and immediate treatment could explain the avoidance of a fatal outcome.  相似文献   
2.
PURPOSE: To examine benzoporphyrin derivative angiography as a modality for studying photosensitizer biodistribution in experimental choroidal melanomas. METHODS: A liposomal preparation of benzoporphyrin derivative was used in this study. Digital benzoporphyrin derivative angiograms were performed in 10 rabbits (six for experimental choroidal melanomas, two for normal choroids, and two for irides) using a Topcon ImageNet H1024 digital imaging system, a Kodak Megaplus video camera, and a Topcon TRC-50-VT fundus camera. Only one eye from each rabbit was used. Filters specifically designed for benzoporphyrin derivative (peak absorption at 580 nm and peak emission at 695 nm) were used. Benzoporphyrin derivative (1 mg/kg) was injected into an ear vein while images of tumor, normal choroid, or iris were being obtained. Follow-up images were obtained during the first 3 hours and at 24 hours after injection. Fluorescence microscopy was performed in all 10 rabbits using 1 mg/kg of benzoporphyrin derivative. Tumor-bearing eyes were enucleated at the same time points that angiograms were performed, and the two sets of results were compared for maximum dye accumulation. RESULTS: Digital angiography demonstrated that maximal benzoporphyrin derivative fluorescence occurred in tumors 15 to 45 minutes after injection. Fluorescence photometry corroborated these results. CONCLUSION: Photosensitizer angiography is a valid modality for determining the optimum treatment time for photodynamic therapy.  相似文献   
3.
OBJECTIVE: To determine whether the type of prosthetic material and technique of placement influenced long-term complications after repair of incisional hernias. DESIGN: Retrospective cohort analytic study. SETTING: University-affiliated hospital. PATIENTS: Two hundred patients undergoing open repair of abdominal incisional hernias with prosthetic material between 1985 and 1994. INTERVENTIONS: Four types of prosthetic material were used and placed either as an onlay, underlay, sandwich, or finger interdigitation technique. The materials were monofilamented polypropylene mesh (Marlex, Davol Inc, Cranston, RI), double-filamented mesh (Prolene, Ethicon Inc, Somerville, NJ), expanded polytetrafluroethylene patch (Gore-Tex, WL Gore & Associates, Phoenix, Ariz) or multifilamented polyester mesh (Mersilene, Ethicon Inc). MAIN OUTCOME MEASURES: The incidence of recurrence and complications such as enterocutaneous fistula, bowel obstruction, and infection with each type of material and technique of repair were compared with univariate and multivariate analysis. RESULTS: On univariate analysis, multifilamented polyester mesh had a significantly higher mean number of complications per patient (4.7 vs 1.4-2.3; P<.002), a higher incidence of fistula formation (16% vs 0%-2%; P<.001), a greater number of infections (16% vs 0%-6%; P<.05), and more recurrent hernias (34% vs 10%-14%; P<.05) than the other materials used. The additional mean length of stay to treat complications was also significantly longer (30 vs 3-7 days; P<.001) when polyester mesh was used. The deleterious effect of polyester mesh on long-term complications was confirmed on multiple logistic regression (P=.002). The technique of placement had no influence on outcome. CONCLUSION: Polyester mesh should no longer be used for incisional hernia repair.  相似文献   
4.
Vibrio parahaemolyticus is an important food-borne enteropathogen that encounters various adverse conditions in its native environment or during infection. Effects of mild acid treatment on survival under stress conditions, enteropathogenicity, and protein production in this pathogen were investigated. Logarithmically grown cells, at pH 7.5 shifted to pH 5.0 for 30 min, were more resistant to subsequent acid challenge at pH 4.4. A two-phase adaptive procedure (pH 5.8 for 30 min; pH 5.0 for 30 min) was better than a single-phase procedure for enhancing the acid tolerance of this pathogen. The acid-adapted cells were cross-protected against the challenges of low salinity and thermal inactivation. One-dimensional polyacrylamide gel electrophoresis revealed that proteins with molecular masses of 6.4, 9.0, 13.6, 16.3, 18.9, 22.9, 24.4, 28.3, 33. 9, 36.9, 41.2, 47.6, 58.1, 65.6, 80.5, 88.2, and 96.9 kDa were induced or significantly enhanced, while proteins of 25.3, 30.1, 30. 7, and 91.7 kDa were significantly inhibited. Two-dimensional polyacrylamide gel electrophoresis revealed that 20 species of proteins were induced or significantly enhanced, while 26 species were inhibited. In assays conducted using the suckling mouse model, enteropathogenicity of the acid-adapted cells was significantly enhanced in terms of intestine/body weight ratio and in vivo recovery of infected cells.  相似文献   
5.
Tomasch (1954) and Aboitiz et al. (1992) found the majority of the fibers of the human corpus callosum are under 1 micron in diameter. Electron microscopic studies of Swadlow et al. (1980) and the detailed study of LaMantia and Rakic (1990a) on macaques show the average size of the myelinated callosal axons also to be less than 1 micron. In man, the average-sized myelinated fiber interconnecting the temporal lobes would have a one-way, interhemispheric delay of over 25 msec. Thus, finely detailed, time-critical neuronal computations (i.e., tasks that strain the capacity of the callosum and hence could not be handled by just the larger fibers) would be performed more quickly via shorter and faster intrahemispheric circuits. While one transit across the commissural system might yield tolerable delays, multiple passes as in a system involving "setting" would seem prohibitively slow. We suggest that these temporal limits will be avoided if the neural apparatus necessary to perform each high-resolution, time-critical task is gathered in one hemisphere. If the, presumably overlapping, neural assemblies needed to handle overlapping tasks are clustered together, this would lead to hemispheric specialization. The prediction follows that the large brains of mammals such as elephants and cetaceans will also manifest a high degree of hemispheric specialization.  相似文献   
6.
A registry was set up by the national college of cardiologists practicing in general hospitals in February 1993. The data concerned mode of admission, demographic details, initial clinical and haemodynamic evaluation and hospital outcome. Special attention was given to the electrocardiographic changes before and, in patients receiving thrombolytic therapy, after treatment. An analysis of predictive factors for mortality was performed both in the group of patients "revascularised" and in the group treated conventionally. One thousand and twenty three cases from 327 centres were analysed. There were 1292 men and 531 women, with an average age of 67.9 years. The average time interval from onset of symptoms to hospital admission was 5 h 30 min, 56.8% of patients arriving within 6 hours. 36.4% of the population underwent thrombolysis or angioplasty, 75% of patients under 75 years of age admitted before the 5th hours underwent a procedure of myocardial revascularisation. The hospital mortality was 14%, 8.7% in those revascularised and 17% in patients treated conventionally. Factors predictive of mortality were age, female gender, Killip Classes III or IV, systolic blood pressure of less than 100 mmHg, heart rate of more than 100/min and contraindications of thrombolysis. The maximum ST depression, the sum of ST depression, the sum of ST elevation and depression, were also significant predictive factors of a fatal hospital outcome in the whole population group and in patients treated conventionally. In the reperfused group, only the initial sum of ST elevation and depression was predictive of mortality: 120 minutes after the beginning of thrombolysis, the sum of ST elevations and of elevations and depressions was predictive of twice the mortality when the values exceeded 0.6 mv and 1.4 mv respectively.  相似文献   
7.
8.
The organization of axonal projections from the basomedial nucleus of the amygdala (BMA) was examined with the Phaseolus vulgaris leucoagglutinin (PHAL) method in adult male rats. The anterior and posterior parts of the BMA, recognized on cytoarchitectonic grounds, display very different projection patterns. Within the amygdala, the anterior basomedial nucleus (BMAa) heavily innervates the central, medial, and anterior cortical nuclei. In contrast, the posterior basomedial nucleus (BMAp) sends a dense projection to the lateral nucleus, and to restricted parts of the central and medial nuclei. Extra-amygdalar projections from the BMA are divided into ascending and descending components. The former end in the cerebral cortex, striatum, and septum. The BMAa mainly innervates olfactory (piriform, transitional) and insular areas, whereas the BMAp also innervates inferior temporal (perirhinal, ectorhinal) and medial prefrontal (infralimbic, prelimbic) areas and the hippocampal formation. Within the striatum, the BMAa densely innervates the striatal fundus, whereas the nucleus accumbens receives a heavy input from the BMAp. Both parts of the BMA send massive projections to distinct regions of the bed nuclei of the stria terminalis. Descending projections from the BMA end primarily in the hypothalamus. The BMAa sends a major input to the lateral hypothalamic area, whereas the BMAp innervates the ventromedial nucleus particularly heavily. Injections were also placed in the anterior cortical nucleus (COAa), a cell group superficially adjacent to the BMAa. PHAL-labeled axons from this cell group mainly ascend into the amygdala and olfactory areas, and descend into the thalamus and lateral hypothalamic area. Based on connections, the COAa and BMAa are part of the same functional system. The results suggest that cytoarchitectonically distinct anterior and posterior parts of the BMA are also hodologically distinct and form parts of distinct anatomical circuits probably involved in mediating different behaviors (for example, feeding and social behaviors vs. emotion-related learning, respectively).  相似文献   
9.
Early and efficient management of severely burned patients facilitates outcome improvement. Pre-hospital care includes fluid loading with 2 mL.kg-1/% burn over the first six hours, sedation and analgesia, prevention of hypothermia and ventilatory support for either critically burned patients or facial, cervical or pulmonary burn injury. The transient stay in a general hospital before transfer to a burn centre allows extension of initial care, the critical investigation for associated injuries (intoxication, multiple trauma) and to perform initial local treatment with sterile coverage or vaseline gauze after a revised assessment of the burned skin area, and possibly escharotomies. The main aim of care in the burn centre is to control hypovolaemia and to obtain maximal tissue perfusion and oxygen delivery to burned tissues, as well as to healthy organs. To manage the burn shock (initially hypovolemic and later on hyperdynamic) catecholamines are often indicated when appropriate fluid loading remains insufficient. Mechanical ventilation is indicated in case of either a deep extensive burn over 60% of total body surface area, or facial and cervical burns or severe pulmonary burn injury from smoke inhalation, carbon monoxide intoxication, tracheobronchial thermal injury and blast injury. Because of the severity of burn-related pain, and the stimulus linked to intensive care, continuous sedation is usually required. Early surgical treatment such as escharotomies, excision and grafting, which cause significant pain as well as blood loss, and hydrotherapy, often require general anaesthesia. Burn injury can modify the volume of distribution and the pharmacokinetics of anaesthetic agents. Finally, chemical or electrical burn, radiation, associated CO intoxication or multiple trauma, as well as burn injury in infants, raise specific problems. With improvement in early intensive care, the survival rate of the most severely burned patients is obviously improving. New techniques in skin substitution will probably further improve the final outcome.  相似文献   
10.
BACKGROUND: Tacrolimus (FK506) may represent a major advance in the management of allograft rejection after solid organ transplantation. In August 1994 a European heart transplantation pilot study was initiated to assess the efficacy and safety of tacrolimus when administered exclusively through an oral route. METHODS: Eighty-two heart transplant recipients were randomized to treatment (2:1 ratio) with either tacrolimus- (n=54) or cyclosporine-based therapy (n=28). RESULTS: No significant differences were evident between the two treatment groups in either rejection or survival rates at 1 year. Kaplan-Meier estimates of the freedom from rejection were 26.3% and 18.5%, respectively, for the tacrolimus and cyclosporine treatment groups (p=.444). Survival rates were 79.6% and 92.9% (p=.125). At 3 of the 5 centers, patients received antithymocyte globulin during the immediate postoperative period and fared better than those who did not (with acute rejection-free rates of 49.2% and 26.7% for tacrolimus and cyclosporine, respectively [p=.080], as opposed to 7.1% and 8.3% [p=.965]; patient survival rates of 84.6% and 93.3% [p=.382] vs 75.0% and 92.3% [p=.243]). The overall rates of infection, impaired renal function (31.5% vs 21.4%), and glucose intolerance (7.0% vs 4.3%) did not differ significantly between the tacrolimus and cyclosporine treatment groups. Tacrolimus seemed to possess an advantage with regard to a reduced requirement for antihypertensive therapy (59.5% vs 87.5%, p=.025). CONCLUSIONS: Immunosuppression with oral tacrolimus provides a viable alternative to treatment with cyclosporine, particularly when administered in conjunction with antibody therapy. Further studies are warranted to optimize the administration of tacrolimus in this indication.  相似文献   
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