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1.
Ten patients with juvenile rheumatoid arthritis and age- and sex-matched healthy controls were investigated in pairs. The patients were found to have both normal proportions and normal absolute numbers of T lymphocytes, B lymphocytes, and the Fc-receptor-bearing lymphoid cells in peripheral blood. No abnormality of mitogen-induced lymphocyte transformation was observed. Lymphocyte-mediated cytotoxicity induced by phytohemagglutinin (PHA) or anti-target cell antibodies was also found to be normal. As in an earlier study, impaired delayed hyper-sensitivity by skin testing was observed in the patient group, thus indicating a dissociation between in vivo and in vitro parameters of lympboid cell function.  相似文献   
2.
The cytotoxicity of human peripheral blood lymphocytes against chicken erythrocytes sensitized by rabbit antibodies was inhibited by human immunoglobulin and immunoglobulin fragments. Myeloma proteins isolated in dimeric state or aggregated by heat treatment inhibited better than the corresponding monomeric proteins. Strong inhibition was observed with IgG1 and IgG3, and with IgG2 after aggregation, while IgG4 inhibited very little. No inhibition was found with IgM, IgA. IgD and IgE. The F(ab')2. and Fab fragments of IgG inhibited poorly or not at all. While- considerable inhibition was observed with the Fc fragment, the pFc' fragment, which roughly corresponds to the C-terminal half of the Fc portion, showed little inhibitory capacity. A fragment isolated from IgG3, containing an extension of the N-terminal part of Fc (the Fch fragment), was an even better inhibitor than tin Fc fragment. The inhibitory capacity of the Fch and Fc fragments was greatly diminished following partial reduction and alkylation On the basis of the inhibitory pattern of IgG fragments, it is suggested that the region on the immunoglobulin molecule involved in binding to the Fc receptor of the effector lymphocytic cell may be located within the CH2 domain.  相似文献   
3.
 Using a fluorescent Ca2+-sensitive dye, we studied the effect of hypo-osmotic stress on the intracellular free Ca2+ concentration ([Ca2+]i) in acini freshly isolated from lactating mouse mammary gland. The basal [Ca2+]i of mammary acini was unaffected by a 50% (v/v) dilution of suspensions with isotonic or hypertonic buffer, or after ionic (iso-osmotic) dilution (external Ca2+ was 3 mM). Hypo-osmotic dilution (50%) elicited a rapid increase in [Ca2+]i comprising a large, transient elevation, followed by a maintained plateau phase. No hypo-osmotically induced rise in [Ca2+]i was observed in the absence of extracellular Ca2+. Neither microtubule disassembly using nocodazole nor actin disruption with cytochalasin D prevented hypo-osmotically evoked stimulation of [Ca2+]i. Pre-incubation of acini with nifedipine did not prevent hypo-osmotically induced stimulation of [Ca2+]i, whereas a non-specific cation channel blocker, gadolinium, partially inhibited the increases in [Ca2+]i induced by hypo-osmotic stress. Furthermore, the transient component was still apparent, and not diminished in magnitude, after [Ca2+]i had been elevated by mobilisation of Ca2+ from intracellular stores using thapsigargin. The results demonstrate that hypo-osmotic stress generates an increase in [Ca2+]i in lactating mammary epithelial cells, the major, transient component of which appears to be due to influx of extracellular Ca2+. Received: 15 October 1996 / Received after revision and accepted: 1 November 1996  相似文献   
4.
Ultrasound scans of 51 consecutive patients with gallbladder wall thickening were reviewed, and specific sonographic features were correlated with surgical and clinical follow-up. Two patterns of thickening were identified as specific indicators of the presence or absence of acute cholecystitis. "Striated" wall thickening, consisting of several alternating, irregular, discontinuous, lucent and echogenic bands, was seen in eight of 13 patients (62%) with acute cholecystitis. This pattern was not encountered in any of the patients who did not have acute cholecystitis. Conversely, "three-layer" thickening, consisting of a single circumferential lucent zone between two relatively uniform echogenic layers, was seen in only one of 13 patients (8%) with acute cholecystitis but in 11 of 38 patients (29%) with other diagnoses. Other abnormalities, including the presence of intramural echogenic foci and wall irregularities, were more frequently seen in patients with acute cholecystitis but were not as helpful. Use of these features may suggest or help exclude a diagnosis of acute cholecystitis in those patients in whom the cause of gallbladder wall thickening is otherwise not apparent.  相似文献   
5.
IntroductionReoperative parathyroidectomy for persistent and recurrent primary hyperparathyroidism is dependent on radiology. This study aimed to compare outcomes in reoperative parathyroidectomy at a single centre using a combination of traditional and newer imaging studies.Materials and methodsRetrospective case note review of all reoperative parathyroidectomies for persistent and recurrent primary hyperparathyroidism over five years (June 2014 to June 2019; group A). Imaging modalities used and their positive predictive value, complications and cure rates were compared with a published dataset spanning the preceding nine years (group B).ResultsFrom over 2000 parathyroidectomies, 147 were reoperations (101 in group A and 46 in group B). Age and sex ratios were similar (56 vs 62 years; 77% vs 72% female). Ultrasound use remains high and shows better positive predictive value (76% vs 57 %). 99mTc-sestamibi use has declined (79% vs 91%) but the positive predictive value has improved (74% vs 53%). 4DCT use has almost doubled (61% vs 37%) with better positive predictive value (88% vs 75%). 18F-fluorocholine positron emission tomography-computed tomography and ultrasound-guided fine-needle aspiration for parathyroid hormone are novel modalities only available for group A. Both carried a positive predictive value of 100%. Venous sampling with or without angiography use has decreased (35% vs 39%) but maintains a high positive predictive value (86% vs 91%). Cure rates were similar (96% vs 100%). Group A had 5% permanent hypoparathyroidism, 1% permanent vocal cord palsy and 1% haematoma requiring reoperation. No complications for group B.ConclusionOptimal imaging is key to good cure rates in reoperative parathyroidectomy. High-quality, non-interventional imaging techniques have produced a shift in the preoperative algorithm without compromising outcomes.  相似文献   
6.
Treatment of fractures of the distal end of the femur in an elderly patient is difficult. If the knee joint is arthritic, the problem is even greater. The reports of two patients with rheumatoid arthritis who sustained fractures of the distal end of the femur and underwent unconventional treatment with a resection total knee arthroplasty are presented.  相似文献   
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Background

Traumatic brain injury is common. Guidelines from the Brain Trauma Foundation and the Scottish Intercollegiate Guidelines Network recommend that patients with suspected severe traumatic brain injury should be treated in centres with neurosurgical expertise. Scotland does not have a framework for the delivery of trauma care. The aim of this study was to examine the demographic characteristics of incidents involving patients who have suffered a suspected traumatic brain injury, and to evaluate the level of the destination healthcare facility which patients are currently taken to.

Methods

Retrospective analysis of prospectively collected Scottish Ambulance Service data on incidents involving traumatic injury, between Nov 2008 and Oct 2010. Two groups of casualties were analysed: those who had a Glasgow coma scale of less than 14 (GCS < 14), and those who had a Glasgow coma scale of less than 9 (GCS < 9).

Results

126,934 incidents were identified and analysed. 3890 (3.1%) patients had a GCS of less than 14, and 657 (0.5% of total) had a GCS of less than 9. Almost one-third of incidents involving patients with either a GCS < 14 or GCS < 9 occurred in the greater Glasgow health board area. The Lothian health board region had the second-highest number of patients with either a GCS < 14 or GCS < 9. Only 13.8% of patients with a GCS < 14, and 16.7% of those with a GCS < 9, were taken to a hospital with a neurosurgical service.

Conclusions

Many patients who may harbour a traumatic brain injury are taken to a facility which may not be equipped or staffed to deal with such injuries. This mismatch needs to be addressed. However, the care of patients with head injuries is only one aspect of trauma care. The UK has long lagged behind North America in terms of the quality of trauma care provided, although the provision of trauma care in England is currently undergoing major changes. Scotland should consider the development of a similar service delivery framework.  相似文献   
10.
The molecular characterization of the mutations in hemophilia A patients is hampered by the large size of the factor VIII gene and the great heterogeneity of mutations. In this study, we have performed a protocol involving multiplex polymerase chain reaction in which 19 exons were amplified in four different combinations followed by nonradioactive single-strand conformational polymorphism (SSCP) to screen for mutations. Southern blotting was used to detect inversion of the factor VIII gene resulting from recombination between copies of the gene A (F8A) located in intron 22 of the factor VIII gene and two copies close telomeric region of X chromosome. Forty-two hemophilia A patients (21 with severe and 21 with mild-to-moderate disease) were studied. The inversion of factor VIII occurred in 13 of 21 patients affected by severe hemophilia A. One patient showed a large extra band in addition to the three bands observed after Southern blotting with the F8A probe. An abnormal electrophoretic pattern of SSCP was detected in 85% and 50% of the patients affected by mild-to-moderate and severe disease, respectively. Sixteen different mutations were identified. Eleven mutations were novel and comprised 9 point mutations and 2 small deletions. This study shows that the methodology used is safe and rapid and has potential for detecting almost all of the genetic defects of the studied hemophilia A patients.  相似文献   
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