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101.
The relative immunogenicity of the H-7.1 alloantigen has been shown in a previous communication to be regulated by a gene in the D region of the mouse major histocompatibility (H-2) complex. The level of relative immunogenicity was inferred from survival times of H-7.1-incompatible skin grafts donated by donors with different H-2 haplotype origins of H-2D region genes. In this communication we report the results of an extension of these previous investigations into the possible role of H-2D region genes in controlling the capacity of H-7.1-incompatible lymphocytes to stimulate H-7.1-speciflc mixed lymphocyte culture proliferation and generation of cytotoxic effector cells. The results reported herein demonstrate that the H-2D genotype of H-7.1-incompatible stimulator cells determines the relative H-7.1-specific capacity of those lymphocytes to stimulate H-7.1-specific proliferation of in vivo primed responder T cells in secondary mixed lymphocyte culture. H-2D(b)-bearing, H-7.l-incompatible stimulators were significantly more effective in stimulating H-7.1-specific proliferation than H-2D(d)-bearing stimulators. As expected, H-2D(b), H-7.1-in-compatible stimulators were also more effective than H-2D(d) a stimulators in generating H-7.1- specific cytotoxic effector cells. Further, the susceptibility of (51)Cr- labeled, H-7.1-incompatible lymphoblast targets to H-7.1-specific lysis was similarly regulated by an H-2D gene. Reciprocal H-2 restriction (F(1) cells are capable of killing only the cells bearing the immunizing cell parental H-2 haplotype) observed by other investigators for cytolysis of non-H-2-incompatible targets was not observed. H-2D a-bearing, H-7.1- incompatible stimulators stimulated generation of cytotoxic effectors capable of detectably lysing H-2D(b) but not H-2D(a)-bearing, H-7.1- incompatible targets. The impact of these observations on the proposed models for H-2 restriction of non-H-2 histocompatibility antigen-specific cytolysis is discussed.  相似文献   
102.
Two patients with Type 1 (adult) Gaucher's disease and majorskeletal involvement with multiple fractures have been treatedwith the second generation bisphosphonate pamidronate for extensiveperiods. There was evidence of an immediate reduction in boneresorption, with increased calcium absorption (delayed in Patient1), improved calcium balance and maintained or improved bonedensity indices in the axial and peripheral skeleton. Therewas no evidence of immediate relapse on treatment cessation.No toxic effects of pamidronate treatment were identified andsubjective skeletal pain diminished in both patients. Histomorphometryof transiliac bone biopsies obtained before the start of treatment,after double in vivo tetracycline labelling, represents oneof the earliest reports of the quantitative findings in iliacbone invaded by Gaucher cells.  相似文献   
103.
Most Ig receptors exist as hetero-oligomeric complexes with separate ligand binding (alpha) and signal transducing (beta, gamma, or zeta) subunits. For Fc gamma RIIIa and Fc epsilon RI, association with the FcR gamma-chain is essential for surface expression. However, the human high affinity IgG receptor, hFc gamma RI, was found to be surface- expressed by itself in transient transfection models. We have now analyzed the integrity of hFc gamma RI expression in more detail in stable transfectants. In vitro we noted that, in the absence of FcR gamma-chain, surface expression of hFc gamma RI rapidly declined to background levels, in both IIA1.6 B cells and NIH3T3 fibroblasts. The effect of FcR gamma-chain on hFc gamma RI surface expression in vivo was evaluated by using two newly generated transgenic mouse lines, selectively expressing hFc gamma RI on myeloid cells. These transgenic mice were crossed with FcR gamma-chain-deficient mice. Analysis of blood monocytes and peritoneal macrophages showed that surface expression of hFc gamma RI was reduced by approximately 80%. The remaining approximately 20% of receptors were still capable of binding IgG-opsonized RBC, suggesting FcR gamma-chain not to be critical for hFc gamma RI ligand-binding capacity. Importantly, however, hFc gamma RI signaling capacity was lost in FcR gamma-chain-deficient cells. No phagocytosis could be observed using either ligand sensitized (EA- IgG2a) or CD64-targeted erythrocytes (using a bispecific antibody) in both hFc gamma RI transgenic lines. This documents the FcR gamma-chain to be indispensable for both surface membrane expression and function of human Fc gamma RI in vivo.  相似文献   
104.
Mycobacterial Infections After Renal Transplantation   总被引:5,自引:0,他引:5  
Mycobacterial infections occurred in 11 of 633 (1.7 per cent)recipients of successful renal transplants. There were no casesof tuberculosis in patients receiving chemoprophylaxis, butamongst those who did not receive prophylaxis disease occurredin six of the 27 (22 per cent) high-risk patients. The majorcause of morbidity during treatment was renal allograft rejection,largely due to reduction in immunosuppressive drug therapy.  相似文献   
105.

Introduction

Rectal polypectomy causes thinning (or even perforation) of the rectal wall in addition to thermic injury at the polypectomy site.

Case report

We present a rare case of spontaneous rectal perforation after uncomplicated nerve sparing endoscopic extraperitoneal radical prostatectomy in a patient with a previous history of rectal polypectomy at the perforation site. The patient could be treated conservatively. There was complete healing of the fistula without any effect on functional results. This Conservative therapy for such rectal perforations is indicated if the patient''s general condition remains stable without any signs of infection.

Conclusions

Polypectomy is an important risk factor for rectal perforation during nsEERPE. Adequate time interval should be given to allow healing and avoid adding further thermal wall damage which may obscure healing leading to complications like fistula. Conservative therapy for small missed rectal perforations constitutes an attractive, feasible and non invasive treatment entity. Following this principle we have not faced this complication in following similar cases.  相似文献   
106.
Background:  Van der Woude syndrome (VWS) is the most common clefting syndrome in humans. It is characterized by the association of congenital lower lip fistulae with cleft lip and/or cleft palate. VWS individuals have a high prevalence of hypodontia. Although caused by a single gene mutation, VWS has variable phenotypic expression. This study aimed to describe the range of clinical presentations in 22 individuals with VWS to facilitate its diagnosis.
Methods:  A retrospective study of 22 patients with a diagnosis of VWS was undertaken at the Australian Craniofacial Unit (ACFU) in Adelaide. Three extended families with affected members were included in the study cohort.
Results:  The overall prevalence of lip pits in this study cohort was 86%. Cleft phenotypes included bilateral cleft lip and palate (32%); unilateral cleft lip and palate (32%); submucous cleft palate (23%); and isolated cleft hard and soft palate (9%). Missing permanent teeth were reported in 86% of affected individuals.
Conclusions:  Submucous cleft palate in VWS may go undiagnosed if the lower lip pits are not detected. Associated hypodontia and resultant malocclusions will also require management by a dental team.  相似文献   
107.
BACKGROUND/OBJECTIVE: To determine factors associated with falls among a sample of ambulatory individuals with incomplete spinal cord injury (SCI). STUDY DESIGN: Cross-sectional mail survey. METHODS: A survey instrument of participant characteristics and fall-related variables was developed using relevant items from existing measures and was mailed to 221 individuals with incomplete SCI, who were identified from records of a large specialty hospital in the southeastern United States. Of the 221 prospective participants, 119 completed the questionnaire (54%). Multivariable logistic regression models were used to determine factors that were independently associated with having had a fall in the past year. RESULTS: After adjusting for covariates, having fallen in the past year was significantly (P < 0.05) associated with greater numbers of medical conditions (odds ratio [OR] = 1.3; 95% confidence interval [CI] = 1.0-1.7), having arthritis (OR = 3.4, 95% CI = 1.2-9.6), experiencing dizziness (OR = 5.6, 95% Cl = 1.1-27.7), greater numbers of days with poor physical health (OR = 1.1; 95% Cl = 1.0-1.3), and the restriction of community activities because of fear of falling (OR = 1.5, 95% CI = 1.1-2.1). The multivariable models also showed that the odds of having fallen were significantly lower among those with better current perceived physical health (OR = 0.5; 95% Cl = 0.3-0.9), those with better perceived health compared to a year ago (OR = 0.4; 95% Cl = 0.2-0.8), individuals who exercised more frequently (OR = 0.2; 95% CI = 0.1-0.7), and those who used a walker (OR = 0.3; 95% CI = 0.1-0.9). CONCLUSIONS: Results suggest that interventions that address exercise frequency, walker use, and dizziness have promise for reducing falls for individuals with incomplete SCI.  相似文献   
108.
Background As a result of the high prevalence, basal cell carcinoma (BCC) causes a significant and expensive health care problem. Objective In this study, we evaluate the proportional increase in BCC by histological subtype over the last two decades. Methods We retrospectively reviewed all primary histological confirmed BCCs diagnosed in the Maastricht University Medical Centre in The Netherlands in the years 1991, 1999 and 2007. Results An annual increase of the number of BCCs of 7% for both genders was shown. The age‐standardized incidence rates for BCC increased between 1991 and 2007 from 54.2 to 162.1 per 100 000 men and from 61.7 to 189.8 per 100 000 women. The proportion of superficial BCC increased significantly from 17.6% to 30.7%. Conclusion The incidence of BCC is continuing to increase this century. The observed shift to the superficial histological subtype, which can be treated non‐surgically, might reduce the workload in the busy dermatologists practice.  相似文献   
109.
It remains an open question as to whether cortical spreading depression (CSD) is the pathophysiological correlate of the neurological symptoms in migraine with aura. In the experimental animal, CSD is an electrophysiological phenomenon mainly mediated via NMDA receptors. However, according to case reports in humans, visual aura in migraine can be alleviated by vasodilator substances, such as amyl nitrite and isoprenaline. There is also circumstantial evidence that brainstem nuclei (dorsal raphe nucleus and locus coeruleus) may play a pivotal role in the initiation of aura. In this study, CSD was elicited in alpha-chloralose anesthetized cats by cortical needle stab injury and monitored by means of laser Doppler flowmetry. Topical application of isoprenaline (0.1-1%) and amyl nitrite (0.05%) onto the exposed cortex had no effect on the elicitation or propagation of CSD. Also, after supracollicular transection, subsequent CSDs showed no differences in the speed of propagation and associated flow changes. We conclude from these data that--given CSD probably exists in humans during migraine--spreading neurological deficits during migraine aura are independent of brainstem influence and have a primarily neuronal rather than vascular mechanism of generation.  相似文献   
110.
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