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31.
Functional studies have shown that the murine macrophage resistance gene Lsh/Ity/Bcg (candidate Nramp) regulates macrophage priming/activation for antimicrobial activity via the tumour necrosis factor-alpha (TNF-alpha)-dependent production of reactive nitrogen intermediates. Since Toxoplasma gondii also parasitizes macrophages, is a stimulator of endogenous TNF-alpha release, and is sensitive to nitric oxide-mediated killing in activated macrophages, studies were carried out using chromosome 1 congenic mouse strains to determine whether Lsh influences T. gondii infection. Two interesting observations were made: (i) contrary to expectation, mice carrying the Lsh-resistant allele died earlier over the acute phase of infection than Lsh-susceptible mice; and (ii) Lsh-resistant mice which survived this acute phase of infection showed lower brain cyst numbers than the Lsh-susceptible mice. Whilst the latter occurred independently of route of inoculation (oral, intraperitoneal, or subcutaneous), the former was influenced both by the route of inoculation and the genetic background on which the Lsh-resistant allele had been isolated. Hence, following oral administration of 20 brain cysts of the RRA strain of T. gondii, mice carrying the Lsh-resistant allele on a B10 genetic background showed a significantly enhanced rate of mortality over the acute (first 8-12 days) phase of infection than B10 Lsh-susceptible mice. Although this acute phase of infection in B10 background mice was accompanied by an increase in serum TNF-alpha levels in both Lsh-resistant and -susceptible mouse strains, early mortality preceded the TNF-alpha peak, and administration of neutralizing rabbit anti-TNF-alpha did not significantly enhance survival. Hence, inflammatory mediators other than TNF-alpha appear to be responsible for the increased rate of acute mortality observed in resistant mice. Infection intraperitoneally led to delayed mortality in B10 mice, with the mean time to 50% mortality now being significantly longer in Lsh-resistant than in Lsh-susceptible mice. On a BALB genetic background, it was the i.p. route of infection which led to acute mortality and more rapid death in the Lsh-resistant strain. When a less virulent inoculum was used and mortality delayed, Lsh-susceptible mice died more rapidly, and i.p. administration of rabbit anti-TNF-alpha led to 100% mortality between days 8 and 10 of infection in both susceptible and resistant mouse strains, consistent with a crucial protective role for TNF-alpha during this phase of infection.(ABSTRACT TRUNCATED AT 400 WORDS)  相似文献   
32.
Fifty consecutive cases of surgical instrumentation and fusion for adolescent idiopathic scoliosis were prospectively studied to test the hypothesis that the use of predonated autologous blood combined with judicious perioperative blood salvage could decrease the amount of homologous blood needed. All cases had posterior instrumentation and fusion. Nineteen patients had their rib prominence resected with an average of 4.8 ribs per patient. Our protocol called for perioperative blood salvage with the cell saver and reinfusion of postoperative drained blood if more than 300 ml were drained in 4 hours. Two units of predonated autologous blood was made available. Hypotensive anesthesia and meticulous hemostasis kept the blood loss to a minimum. The average total blood loss was 1,055 ml. Blood loss per segment was 91 ml with an average of 11 segments fused per patient. Patients with rib resection had a blood loss of 1,105 ml, while those without had a blood loss of 955 ml. The cell saver blood returned per case was 391 ml with the hematocrit of the product averaging 46%. Twelve patients were reinfused an average of 300 ml of the postoperative drained blood. The predonated autologous blood was used as part of the intraoperative fluid management. In no patient was homologous blood needed. The average starting hematocrit was 35.6%, with the hematocrit at discharge (seventh day) being 32.4%. There were no complications or blood transfusion reactions. Our results suggest that judicious perioperative blood management may decrease the need for homologous blood transfusion in selected posterior idiopathic scoliosis surgery.  相似文献   
33.
The surgical procedures used, the complications encountered and the results obtained in 549 patients with urinary stress incontinence with or without prolapse and 50 patients with prolapse without urinary stress incontinence are presented. Incontinence was cured in 347 patients, improved in 126, unchanged in 66 and worsened in ten. Seven patients operated on for uterine prolapse developed urinary incontinence after surgery. The overall recurrence of SUI was 12.75%. The introduction of suprapubic bladder drainage has practically eliminated postoperative urinary tract infections and reduced the length of hospitalization from 9.1 to 7.2 days. My experience in 214 patients with suprabpubic drainage demonstratedthe superiority of the Ansari method over the cystocath. The addition of Cantor's bladder neck plication improved the results (cured plus improved) from 80% to 100% in the Marshall-Marchetti-Krantz operation and from 81% to 86% when the Marshall-Marchetti-Krantz operation was associated with an abdominal hysterectomy.  相似文献   
34.
The pathogenesis of experimental meningococcal septicemia and the efficacy of heparin sodium therapy were evaluated by inoculating rabbits intraperitoneally with type B meningococci in mucin. Half the rabbits died, and the respiratory distress and circulatory failure that occurred during the terminal phase of the disease were associated with diffuse pulmonary capillary and venular thrombosis and with renal glomerular fibrin deposition. Platelet and leukocyte counts and plasma fibrinogen levels decreased in all rabbits, and prothrombin and partial thromboplastin times were prolonged. Pretreatment with heparin sodium diminished intravascular fibrin deposition but failed to prevent the pulmonary microthrombi and did not either reduce the mortality or improve the survival time. We conclude that death in meningococcal septicemia is due to widespread thrombosis of the pulmonary microcirculation. The disease is complicated by diffuse intravascular coagulation, which can be controlled with heparin sodium but which is not immediately life-threatening.  相似文献   
35.
The authors review recent and current literature on the relationship between psychological factors and cancer. They discuss the roles of predisposing personality patterns and emotional stress in the development, site, and course of cancer; the influence of awareness of terminal illness on the behavior of cancer patients; and the management of psychiatric symptoms in these patients.  相似文献   
36.
A study was performed utilizing 3 mock eyes of different sizes to determine the precision and accuracy of 3 radiographic methods of localization of intraorbital foreign bodies. The Comberg method was found to be the most precise and accurate, next, the Sweet method, and then the modified spectacle frame method. However, the modified spectacle frame field expedient method of localization yielded a surprisingly high degree of accuracy in 2 of the 3 planes of reference, that is, mediolaterally and superointeriorly. A more accurate field expedient type of device which will permit greater accuracy in localization of intraorbital foreign bodies in the anteroposterior axis is currently under development.  相似文献   
37.
The effects of intra-arterial infusion of E. coli endotoxin at 1.0 mg. per minute on the gastric total and mucosal blood flows, electrical potential difference, and ionic fluxes across the gastric mucosa were studied in an exteriorized, chambered preparation of canine fundic stomach. Gamma-labelled microsphere technique was used in addition to venous drainage and plasma aminopyrine clearance for the measurement of total and mucosal blood flow, respectively. In spite of normal systemic blood pressure throughout the experiment, E. coli endotoxin infusion caused a significant decrease in total gastric blood flow and in the fractional distribution of flow to the mucosae. There was no significant arteriovenous shunting of microspheres. Significant reduction in potential difference and hydrogen-ion back diffusion also was noted after endotoxin infusion, possibly as a consequence of reduced mucosal blood flow. The results indicate that significant gastric mucosal ischemia can occur and may represent a mechanism in the development of gastric erosions in endotoxemia, even in the absence of systemic hypotension.  相似文献   
38.
Middle ear effusion has been considered the most common cause of vestibular disturbance in children. However, there have been only a few studies on vestibular disturbance in children with otitis media with effusion. We studied the vestibular systems of 30 children with otitis media with effusion aged 8 to 13 years and compared the results with 15 age- and sex-matched controls. A questionnaire relating to vestibular disturbance was given to patients and their parents. Spontaneous nystagmus and positional nystagmus were recorded by electronystagmography as diagnostic tests of the vestibular system. Romberg's and past-pointing tests were performed on children with otitis media with effusion and controls. After vestibular tests were completed, myringotomy was performed, and a ventilation tube was inserted. The questionnaire and the vestibular tests were repeated after the operation and during the first month after surgery. Our study showed that there was a history of vestibular disturbance in 33% of children with otitis media with effusion. Electronystagmography and Romberg's test findings demonstrated that 33% of the children had vestibular dysfunction (p < 0.05). After myringotomy with ventilation tube insertion, vestibular test results returned to normal, and symptoms related to vestibular disturbance improved. These findings confirm the assumption that middle ear effusion may affect the vestibular system, which can be resolved after myringotomy with ventilation tube insertion.  相似文献   
39.
Mice deficient in the cytokines tumor necrosis factor (TNF) or lymphotoxin (LT) alpha/beta lack polarized B cell follicles in the spleen. Deficiency in CXC chemokine receptor 5 (CXCR5), a receptor for B lymphocyte chemoattractant (BLC), also causes loss of splenic follicles. Here we report that BLC expression by follicular stromal cells is defective in TNF-, TNF receptor 1 (TNFR1)-, LTalpha- and LTbeta-deficient mice. Treatment of adult mice with antagonists of LTalpha1beta2 also leads to decreased BLC expression. These findings indicate that LTalpha1beta2 and TNF have a role upstream of BLC/CXCR5 in the process of follicle formation. In addition to disrupted follicles, LT-deficient animals have disorganized T zones. Expression of the T cell attractant, secondary lymphoid tissue chemokine (SLC), by T zone stromal cells is found to be markedly depressed in LTalpha-, and LTbeta-deficient mice. Expression of the SLC-related chemokine, Epstein Barr virus-induced molecule 1 ligand chemokine (ELC), is also reduced. Exploring the basis for the reduced SLC expression led to identification of further disruptions in T zone stromal cells. Together these findings indicate that LTalpha1beta2 and TNF are required for the development and function of B and T zone stromal cells that make chemokines necessary for lymphocyte compartmentalization in the spleen.  相似文献   
40.
A triplet pregnancy in a 23-year-old woman was terminated at 15 weeks of gestation because of her severe hypertension, lung edema, and secondary hyperthyroidism. The pregnancy consisted of a hydatidiform mole with a 46,XY karyotype and two fetuses each with 46,XX and a 46,XY karyotype. To determine the zygosity and genetic origin of the mole and fetuses, PCR- and computer-assisted genotyping were performed at 27 CA-repeat marker loci that were distributed evenly over the genome. As a result, genotypes of the three pregnancy products were distinct from each other, indicating that the triplets were trizygotic. The mole lacked any maternal alleles but inherited both of the paternal alleles and/or one paternal allele in duplicate. This, along with the XY sex chromosome constitution, indicated that the mole resulted from dispermic androgenesis. The mother developed a persistent trophoblastic tumor thereafter.  相似文献   
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