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51.
Tuberculous mastitis is rare, especially in Western countries. We describe a case where the interferon gamma release assay blood test led to diagnosis and successful treatment of the disease.  相似文献   
52.
Quantification of carotid stenosis on CT angiography   总被引:6,自引:0,他引:6  
PURPOSE: Carotid artery stenosis quantification uses percent diameter ratios from conventional angiography. Multidetector high-speed CT angiography (CTA) allows direct millimeter measurement of carotid stenosis. We hypothesize a linear relationship between millimeter stenosis measurements and derived percent, alleviating cumbersome ratio calculations. METHODS: Two neuroradiologists separately reviewed CTAs of 268 carotid arteries, blinded to other information. The narrowest portion of each carotid stenosis was measured in millimeters from axial source images. Distal internal carotid arteries (ICAs) were measured beyond the bulb, where walls are parallel. North American Symptomatic Carotid Endarterectomy Trial (NASCET)-style ratios were calculated for each ICA, except for suspected near-occlusions. Interobserver agreement was calculated for all measurements. Correlation coefficients were calculated comparing millimeter and derived percent stenosis, followed by regression analysis. Sensitivity and specificity values tested validity. RESULTS: Interobserver agreement correlations were excellent, from 0.78 to 0.89 (2-tailed P 相似文献   
53.
A new approach to CNS repair using chimeric peripheral nerve grafts   总被引:10,自引:0,他引:10  
We have examined whether transplanted freeze-thawed peripheral nerve (PN) sheaths repopulated ex vivo with purified adult Schwann cells (SCs) support the regeneration of adult rat retinal ganglion cell (RGC) axons. Cultured adult SCs were derived from donor rats or from the host animals themselves. We also transplanted PN sheaths filled with neonatal SCs or donor adult olfactory ensheathing glia (OEG). 100,000 cells were injected into 1.5-cm lengths of freeze-thawed PN. After 2 days in culture, repopulated PN segments were grafted onto the transected optic nerve of adult Fischer rats. Three weeks later, 6% fluorogold (FG) was applied to distal PN. Retrogradely labeled RGCs were counted in retinal wholemounts and PN grafts were processed for immunohistochemistry. As expected, there was no RGC axon regeneration in cell-free grafts. Regrowth was also absent in neonatal SC- and adult OEG-filled grafts, which contained only small numbers of surviving donor cells. Many cells were, however, seen in adult SC repopulated PN grafts, intermingled with pan-neurofilament(+) and GAP-43(+) fibers. SCs were aligned along the grafts and were S-100(+), p75(+). Ultrastructurally, SCs were associated with myelinated and unmyelinated axons. Hundreds of FG-labeled RGCs were seen in retinas of rats with congeneic or allogeneic PN sheaths repopulated with either donor or autologous (host-derived) adult SCs. Intraocular CNTF injections significantly increased the number of regenerating RGCs in donor and autologous adult SC groups. The use of chimeric grafts to bridge CNS tissue defects could provide a clinical alternative to using multiple PN autografts, the harvesting of which would exacerbate peripheral dysfunction in already injured patients.  相似文献   
54.
A foot-pad oedema model was used to investigate the presence of free radicals using a chemiluminescence method. This model is an example of a cell mediated hypersensitivity reaction. Male rats were inoculated in the scruff with Freund's Complete Adjuvant (FCA) on Day 0 and then challenged 6 days later with FCA in one hind paw. An acute inflammatory reaction was initiated over the following 96 hours and within 4 hours of induction, reactive oxygen species were detected in the inflamed tissue. A peak of chemiluminescence activity was seen 8 hours after the induction of the inflammatory reaction, well before maximum oedema was observed. Using mannitol, catalase and DABCO to elucidate the nature of the reactive oxygen species it was found that hydroxyl radicals, hydrogen peroxide and singlet oxygen all contributed to this burst of oxidative activity and are therefore probably involved with the process of lipid peroxidation and the severity of an inflammatory reaction.  相似文献   
55.
Salivary levels of biomarkers for the hypothalamic–pituitary–adrenal axis (HPA; cortisol) and sympatho-adreno-medullary system (SAM; α-amylase) were measured in 51 adults (57% male) with neurodevelopmental disorders associated with intellectual disability (i.e., mental retardation) and chronic self-injurious behavior (SIB) and compared with matched controls without SIB. Cortisol levels differed significantly (p < 0.01) between the SIB and control group (SIB > control). Within-group analyses showed significant differences (p < 0.05) in levels of salivary α-amylase between individuals with SIB and those with SIB meeting criteria for stereotyped movement disorder (SMD; SIB + SMD > SIB). Salivary α-amylase was significantly correlated with frequency of stereotypy among the SIB group (r = 0.36, p < 0.05). These preliminary findings warrant further exploration into the role of the SAM system in the pathophysiology of SIB and related repetitive behaviors among individuals with neurodevelopmental disorders associated with intellectual disability.  相似文献   
56.
Role of thromboxane A2 in the cardiovascular response to intracoronary C5a   总被引:1,自引:0,他引:1  
Intracoronary administration of complement component C5a induces transient decreases in coronary blood flow and regional left ventricular segment shortening, associated with intramyocardial granulocyte trapping. We evaluated the influence of a cyclooxygenase inhibitor (acetylsalicylic acid, n = 8) or a thromboxane A2/prostaglandin H2 receptor antagonist (SQ29548, n = 6) on these C5a-induced cardiovascular responses. Open-chest anesthetized pigs were instrumented to monitor heart rate, arterial blood pressure, left anterior descending coronary blood flow, regional left ventricular segment shortening, and dP/dt. Oxygen content, lactate concentration, leukocyte count, and thromboxane B2, the stable metabolite of thromboxane A2, were measured in arterial and regional coronary venous blood. Repetitive injections of intracoronary C5a (500 ng) given 60 minutes apart showed no tachyphylaxis of the hemodynamic response. However, tachyphylaxis was seen in coronary blood flow changes when injections were spaced 30 minutes apart. An increase in myocardial oxygen extraction and lactate production was observed after intracoronary C5a. Administration of acetylsalicylic acid (50 mg/kg i.v.) attenuated C5a-induced decreases in coronary blood flow (-8 +/- vs. -3 +/- 1 ml/min) and regional left ventricular segmental shortening (-10 +/- 3% vs. -2 +/- 1%) and blocked the maximal increase in coronary venous thromboxane B2 (2.0 +/- 0.1 vs. 0.2 +/- 0.1 pmol/ml plasma). Furthermore, SQ29548 (30 micrograms/kg/min) reduced C5a-induced changes in coronary blood flow (-13 +/- 2 vs. -4 +/- 2 ml/min) and segmental shortening (-14 +/- 2% vs. -3 +/- 1%). Neither cyclooxygenase inhibition nor thromboxane A2/prostaglandin H2 antagonism blocked the decrease in coronary venous granulocyte count.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
57.
Fraser  CC; Eaves  CJ; Szilvassy  SJ; Humphries  RK 《Blood》1990,76(6):1071-1076
A large number of biologic, technological, and clinical studies await the development of procedures that will allow totipotent hematopoietic stem cells to be expanded in vitro. Previous work has suggested that hematopoiesis can be reconstituted using transplants of cells from long- term marrow cultures. We have used retrovirus mediated gene transfer to demonstrate that marked totipotent hematopoietic stem cells are both maintained and can be amplified in such cultures, and then subsequently regenerate and sustain lympho-myeloid hematopoiesis in irradiated recipients. Marrow cells from 5-fluorouracil-treated male mice were infected with a recombinant virus carrying the neomycin resistence gene and seeded onto irradiated adherent layers of pre-established, long- term marrow cultures of female origin. At 4 weeks, cells from individual cultures were transplanted into single or multiple female recipients. Southern blot analysis of hematopoietic tissue 45 days posttransplantation showed retrovirally marked clones common to lymphoid and myeloid tissues in 14 of 23 mice examined. Strikingly, for 3 of 4 long-term cultures, multiple recipients of cells from a single flask showed marrow and thymus repopulation with the same unique retrovirally marked clone. These results establish the feasibility of retroviral-marking techniques to demonstrate the maintenance of totipotent lympho-myeloid stem cells for at least 4 weeks in the long- term marrow culture system and provide the first evidence of their proliferation in vitro. Therefore, such cultures may serve as a starting point for identifying factors that stimulate totipotent hematopoietic stem cell expansion.  相似文献   
58.
Soluble CD8 in patients with rheumatic diseases.   总被引:2,自引:6,他引:2       下载免费PDF全文
An ELISA was used to measure soluble CD8 (sCD8) in the sera and synovial fluids (SF) of patients with rheumatic diseases. Patients with rheumatoid arthritis (RA) had raised levels of sCD8 both in their sera and in their SF compared with patients with osteoarthritis and age-matched healthy controls. In individual RA patients, serial serum sCD8 levels initially fell and then rose preceding clinical improvement. In four patients where serum sCD8 levels rose and clinical improvement occurred, subsequent spontaneous decreases of serum sCD8 level preceded increased clinical disease activity by up to 2 weeks. In general, RA SF mononuclear cells (SFMNC) spontaneously produced high levels of sCD8. In contrast, autologous peripheral blood MNC only produced comparable levels after mitogenic stimulation. Incubation of SFMNC with increasing concentrations of human recombinant tumour necrosis factor alpha resulted in a dose-dependent potentiation of sCD8 release into the supernatant. There was an inverse relationship between the ability of SFMNC to release sCD8 and soluble interleukin-2 receptor, indicating that the CD8+ T cell population may play an important immunoregulatory role in RA.  相似文献   
59.

Background

Laparoscopic antireflux surgery is an accepted treatment for persistent gastroesophageal reflux but about 4% of patients will eventually require revision surgery.

Methods

We searched The Cochrane Collaboration, Medline, and EMBASE databases, augmented by Google Scholar and PubMed related articles from January 1, 1990, to November 22, 2010. Twenty studies met the inclusion criteria, reporting on 930 surgeries.

Results

The mean surgical duration was 166 minutes and conversion to open revision fundoplication was required in 7% of cases. Complications were reported in 14% of cases and the mean length of stay varied between 1.2 and 6 days. A good to excellent result was reported for 84% of surgeries and 5% of patients required a further revisional procedure.

Conclusions

Laparoscopic revision antireflux surgery appears to be feasible and safe, but subject to somewhat greater risk of conversion, higher morbidity, longer hospital stay, and poorer outcomes than primary laparoscopic fundoplication.  相似文献   
60.
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