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991.
Mouse monoclonal antibodies B1 and B3 are specific for natural and Escherichia coli-derived recombinant human gamma-interferon (IFN-gamma). The two antibodies recognize different epitopes of the IFN-gamma molecule and do not compete with each other's binding. We have used these two antibodies to construct a solid-phase, sandwich immunoradiometric assay for human IFN-gamma. Purified antibody B1 was coated on polystyrene beads (0.64 cm in diameter) and used as the solid-phase immunoadsorbent and antibody B3 was labeled with 125I and used as tracer. This assay can be completed in about 4 hr and is capable of detecting IFN-gamma levels in human serum or tissue culture fluids as low as 0.1 NIH reference unit/ml. Recombinant human IFN-gamma derived from E. coli was detectable at a concentration of 0.02 ng/ml. The assay appears to be specific for the biologically active forms of IFN-gamma, since after exposure to pH 2, 37 degrees C, or 56 degrees C, biological activity and reactivity in the immunoradiometric assay decreased in parallel. The immunoradiometric assay can be employed for the analysis of the structural characteristics of the human IFN-gamma molecule.  相似文献   
992.
This study aimed to identify providers involved in diagnosing ankylosing spondylitis (AS) following back pain diagnosis in the USA and to identify factors leading to the delay in rheumatology referrals. The Truven Health MarketScan® US Commercial Database was searched for patients aged 18–64 years with back pain diagnosis in a non-rheumatology setting followed by AS diagnosis in any setting during January 2000–December 2012. Patients with a rheumatologist visit on or before AS diagnosis were considered referred. Cox regression was used to determine factors associated with referral time after adjusting for age, sex, comorbidities, physician specialty, drug therapy, and imaging procedures. Of 3336 patients included, 1244 (37 %) were referred to and diagnosed by rheumatologists; the others were diagnosed in primary care (25.7 %), chiropractic/physical therapy (7 %), orthopedic surgery (3.8 %), pain clinic (3.6 %), acute care (3.4 %), and other (19.2 %) settings. Median time from back pain diagnosis to rheumatology referral was 307 days and from first rheumatologist visit to AS diagnosis was 28 days. Referred patients were more likely to be younger (hazard ratio [HR]?=?0.986; p?<?0.0001), male (HR?=?1.15; p?=?0.0163), diagnosed with uveitis (HR?=?1.49; p?=?0.0050), referred by primary care physicians (HR?=?1.96; p?<?0.0001), prescribed non-steroidal anti-inflammatory drugs (HR?=?1.55; p?<?0.0001), disease-modifying antirheumatic drugs (HR?=?1.33; p?<?0.0001), and tumor necrosis factor inhibitors (HR?=?1.40; p?=?0.0036), and to have had spinal/pelvic X-ray prior to referral (HR?=?1.28; p?=?0.0003). During 2000–2012, most patients with AS were diagnosed outside of rheumatology practices. The delay before referral to rheumatology was 10 months; AS diagnosis generally followed within a month. Earlier referral of patients with AS signs and symptoms may lead to more timely diagnosis and appropriate treatment.  相似文献   
993.
BACKGROUND: Duodenal duplication cysts are rare congenital anomalies. Symptomatic cases have classically been treated by surgical resection, which can be complex because of the close proximity of the cysts to the papilla. OBJECTIVE: To describe a series of 8 patients with symptomatic duodenal duplication cysts who were treated endoscopically, with a special focus on the long-term outcome. DESIGN: Retrospective case series. SETTING: Three tertiary-care European academic hospitals. PATIENTS: Eight patients, age 8 to 72 years, were treated endoscopically for symptomatic intraluminal duodenal duplication cysts between 1981 and 2006. Seven patients presented with acute pancreatitis, and one patient presented with jaundice. INTERVENTION: Endoscopic incision and marsupialization of the cysts was performed by using a variety of endoscopic tools (needle-knife and regular sphincterotomes, cystotomes, and polypectomy snares). MAIN OUTCOME MEASUREMENTS: Technical success of endoscopic intervention and long-term clinical recurrence of symptoms. RESULTS: No major complications occurred. All patients remained asymptomatic at a median follow-up of 7.3 years. LIMITATIONS: Retrospective study; the small number of patients. CONCLUSIONS: The endoscopic treatment of symptomatic intraluminal duodenal duplication cysts is a safe and effective technique, with excellent long-term results. It represents a minimally invasive alternative to surgical resection and might be considered the preferred therapeutic modality for these cases.  相似文献   
994.
995.
Incidence rates of traumatic brain injury are high in both industrialized and non-industrialized countries and have been estimated variously to be between 150–250 cases per 100,000 population per year. The estimated incidence rates for subarachnoid hemorrhage (SAH) are between 10 to 25 cases per 100,000 population per year. Seasonal variation in the occurrence of subarachnoid hemorrhage has been reported in studies from different countries, with significant seasonal variations and peak periods for aneurysmal SAH differing widely. A differential racial distribution for SAH has been found as well as a higher mortality rate for women than for men. The cognitive and behavioral consequences of TBI and SAH are significant and affect the quality of life of patients and their families. Recent publications have informed of hypopituitary deficits in patients sustaining TBI or SAH. It is not clear whether the cognitive deficits found in these patients are due to the consequences of the brain injury itself or are related to the hypopituitary deficits. There is a need for research distinguishing the differential cognitive and behavioral effects of the brain injury and the endocrinological deficits in these patients, and for developing adequate treatment.  相似文献   
996.
997.
Splenic involvement is a classical complication of infective endocarditis (IE). Clinical manifestations are rare, 5 out of 100 IE: unexpected rupture (1 case), abscess causing reinfection (2 cases), pseudo-tumour (1 case) and terminal infarction (1 case). In addition to a review of the literature, a post mortem histological study of the spleen of 78 cases of IE was undertaken. Splenic involvement did not seem to be the direct cause of death. Three types of lesions which may or may not be associated were observed: congestive inflammatory lesions, infarction (48 p. 100), abscess (6 p. 100). Splenic infarction usually results in scarring but may progress to abscess formation. Rupture was not observed in this autopsy series. Although splenic involvement is common at post mortem it gives rise to few symptoms. Persistant pyrexia and the appearance of local signs should lead to investigation of splenic complications and eventually, to surgical ablation.  相似文献   
998.
The myeloproliferative syndrome induced by the myeloproliferative sarcoma virus (MPSV) in DBA/2 mice stimulates the proliferation of pluripotent hemopoietic stem cells (HSC) and of progenitors committed toward granulomacrophagic and erythroid cell lines. This stimulation may result from a direct effect of the MPSV on HSC or from an indirect effect via locally secreted factors. Normal isogenic bone marrow cells were incubated in the mixed colony-forming unit system in semisolid medium supplemented with conditioned media obtained after incubating neoplastic spleen cells for 3 days at 37 degrees C. These spleen conditioned media contain an activity that is physically separable from MPSV by ultracentrifugation and which, in the presence of a very low quantity of erythropoietin, can induce in vitro the proliferation and differentiation of pluripotent HSC, detected by this Mix-CFU technique. We termed this activity mixed-colonies promoting activity (MPA). These results suggest that the hyperplasia of the nonlymphoid hematopoietic system in the neoplastic spleen results from an indirect effect of the MPSV on pluripotent HSC via locally secreted factors.  相似文献   
999.
Primary cystic pancreatic neoplasms are rare tumors, with an approximate prevalence of 10% of cystic pancreatic lesions. Most of these lesions correspond to mucinous cystic neoplasm, serous cystoadenoma and intraductal papillary mucinous tumor (IPMT). IPMT is characterized by diffuse dilatation of the main pancreatic duct and/or side branches with inner defects related to mucin or tumor, or mucin extrusion from a patent ampulla. IPMT has a low potential for malignancy, with a low growth rate, a low rate of metastatic spread and postsurgical recurrence. Over the last few years, major advances have been made in the diagnostic and therapeutic management of this tumor.  相似文献   
1000.
Kallmann syndrome (KS) is a developmental disease characterized by the association of isolated hypogonadotropic hypogonadism and anosmia/hyposmia. We report an unusual presentation of two females with KS and empty sella. These females, aged at 20 and 29-year-old, presented primary amenorrhea with prepubertal estradiol and low gonadotropin levels. No other significant clinical signs were observed. Empty sella was observed on MRI in both cases. Sequencing of FGFR1 gene, recently implicated in autosomal form of KS, was performed and one splicing mutation (IVS14 + 1G > A) was identified in one patient.  相似文献   
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