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991.
We aimed to determine if changes in the patterns of upper gastrointestinal diseases at endoscopy have occurred over the past decade. Retrospectively, 917 consecutive patients were selected based on upper endoscopy between June 1 and August 31, in 1990 (n = 217), 1994 (n = 270), and 1998 (n = 430). Demographic, clinical, endoscopic, and histological information were extracted from the medical records on a standardized case record form. Over the eight-year period, follow-up of peptic ulcer (15%, 5%, and 5%, respectively, in 1990, 1994, and 1998, df = 2, P < 0.001), bleeding (22%, 14%, and 13%, P = 0.008), and nausea/vomiting (15%, 16%, and 10%, df = 2, P = 0.003) had become less frequent, but reflux (21%, 19%, and 34%, df = 2, P < 0.001) and dyspepsia (24%, 43%, and 32%, df = 2, P < 0.001) more frequent indications for upper endoscopy. The prevalence of peptic ulcer disease decreased (22%, 15%, and 13%, df = 2, P = 0.025), but the prevalence of reflux esophagitis increased significantly (29%, 30%, and 39%, df = 2, P = 0.010). The prevalence of both the use of nonsteroidal antiinflammatory drugs (NSAIDs) (18%, 20%, and 11%, respectively, in 1990, 1994, and 1998, df = 2, P = 0.004) and H. pylori infection (39% in 1994 and 30% in 1998, df = 1, P = 0.032) decreased. Overall, NSAID use was independently associated with gastric ulcers (OR = 2.39, 95% CI 1.21–4.73, 2 = 6.31, df = 1, P = 0.012), but not esophagitis. H. pylori infection was independently associated with duodenal ulcers (OR = 4.74, 95% CI 2.30–9.77, 2 = 17.8, df = 1, P < 0.001), histologically chronic (OR = 166.8, 95% CI 76.1–365.4, 2 = 313.0, df = 1, P < 0.001) and active (OR = 30.1, 95% CI 17.0–53.5, 2 = 189.7, df = 1, P < 0.001) gastritis and lymphoid aggregates (OR = 5.49, 95% CI 3.02–9.97, 2 = 36.3, df = 1, P < 0.001). In conclusion, the prevalence of peptic ulcer disease appears to have been decreasing, whereas reflux esophagitis has been increasing over the past decade in Western Sydney. The decreased use of NSAIDs and decline of H. pylori infection have likely both contributed to the reduction of peptic ulcer disease, but the increase in reflux esophagitis remains to be fully explained.  相似文献   
992.
The trigeminal autonomic cephalalgias (TACs) are a group of primary headache disorders characterised by lateralized symptoms: prominent headache and ipsilateral cranial autonomic features, such as conjunctival injection, lacrimation and rhinorrhea. The TACs are: cluster headache (CH), paroxysmal hemicrania (PH), short‐lasting unilateral neuralgiform headache attacks with conjunctival injection and tearing (SUNCT)/short‐lasting neuralgiform headache attacks with cranial autonomic features (SUNA) and hemicrania continua (HC). Their diagnostic criteria are outlined in the International Classification of Headache Disorders, third edition‐beta (ICHD‐IIIb). These conditions are distinguished by their attack duration and frequency, as well as response to treatment. HC is continuous and by definition responsive to indomethacin. The main differential when considering this headache is chronic migraine. Other TACs are remarkable for their short duration and must be distinguished from other short‐lasting painful conditions, such as trigeminal neuralgia and primary stabbing headache. Cluster headache is characterised by exquisitely painful attacks that occur in discrete episodes lasting 15–180 min a few times a day. In comparison, PH occurs more frequently and is of shorter duration, and like HC is responsive to indomethacin. SUNCT/SUNA is the shortest duration and highest frequency TAC; attacks can occur over a hundred times every day.  相似文献   
993.
Wang  JT; Lin  MT; Chen  PJ; Sheu  JC; Lin  JT; Wang  TH; Chen  DS 《Blood》1994,84(3):934-940
To study the incidence of human T-cell lymphotropic virus (HTLV) after blood transfusion in Taiwan, serum samples from 699 patients in a prospective study were examined for seroreactivity of anti-HTLV. By an enzyme immunoassay, 9 of the 699 recipients were repeatedly positive. Serial serum samples of these 9 patients were then confirmed with a Western blot analysis and with a polymerase chain reaction (PCR) assay for HTLV-I genome. Four were already positive for anti-HTLV before transfusion, 1 carried antibodies to HTLV-I transiently after transfusion, and only 4 cases had de nova seroconversions. These patients and their family members were called back and tested for HTLV- I genome in the peripheral blood mononuclear cell (PBMC) and plasma. All the serologically positive patients, except the "transient one," were positive for HTLV sequences in the PBMCs. Viral sequences could also be detected in several serum or plasma samples. In the family members, only the spouse of a pretransfusion-positive patient was infected. These results suggested that approximately 0.6% of the blood recipients were infected by HTLV-I through transfusion in Taiwan, and that the frequency of intrafamilial HTLV-I transmission is low. We also observed the unusual coinfection by both HTLV-I and hepatitis C virus in 2 patients, and superinfection of hepatitis C virus after blood transfusion in 1 HTLV-I carrier. Cases of coinfection suggest a prevalence of both viruses in blood donors and warrant further screening.  相似文献   
994.
Foot pain: specific indications for scintigraphy   总被引:1,自引:0,他引:1  
Bone scintigraphy is requested as part of the investigation of foot pain, but its contribution to clinical management has not been comprehensively documented. Previously published data are limited; the most comprehensive series identified scintigraphic abnormalities in patients with primarily orthopaedic problems and a control group was not included (Maurice HD et al. J Bone Joint Surg 1987;69B:448 52). The aim of this study was to evaluate whether bone scintigraphy may be useful in different clinical circumstances indicated by referral request details. Regions of scintigraphic abnormality were scored and compared with clinical details drawn from case notes of 60 patients with foot pain. The commonest clinical indications for scans were: confirmation of the clinical suspicion of plantar fasciitis, documentation of the extent of inflammatory arthritis and location of focal pathology. A group of 30 asymptomatic, age- and sex-matched controls were also studied. In 14 out of 19 symptomatic feet in the plantar fasciitis group, focal uptake at the medial calcaneal tubercle was present, confirming the diagnosis. In patients with non-specific, diffuse foot pain, the bone scan identified focal abnormalities in 11 out of 14 cases, thus directing the clinician to the site of pathology. Scintigraphy also proved useful in mapping local inflammatory disease. Technetium-99m methylene diphosphonate image abnormalities occurred in the control group most commonly in the midfoot (16 regions in 13 subjects) and first metatarsophalangeal joint (19 regions in 14 subjects).   相似文献   
995.
Function-related antigens on the neutrophil (PMN) surface were identified using two newly developed PMN-specific mouse monoclonal antibodies. These IgG antibodies, designated Ab 1-14 and Ab 1-15, were selected for detailed study after initial testing revealed their significant inhibition of PMN superoxide generation in response to N- formyl-Met-Leu-Phe (FMLP) (64% for 1-14 and 64% for 1-15; P less than .05). In further experiments, Ab 1-14 augmented PMN adhesion (by 111%; P less than .01) and degranulation (by 52%; P less than .05) in response to FMLP, while Ab 1-15 inhibited these responses by 42% and 29%, respectively (P less than .05). Ab 1-14 reduced PMN chemotaxis in response to FMLP by 37% (P less than .02), and unlike Ab 1-15, Ab 1-14 significantly reduced unstimulated PMN binding of complement-coated sheep red blood cells. Ab 1-14 and Ab 1-15 significantly reduced PMN superoxide production in response to phorbol myristate acetate (PMA) (14% and 23%, respectively; P less than .05). Whereas 1-14 was found to increase PMA-induced cell degranulation significantly (175%), Ab 1-15 did not alter degranulation response to PMA. Immunoprecipitation showed that Ab 1-14 and Ab 1-15 recognized respective surface antigens of 94,000 mol wt and 130,000 to 180,000 mol wt. Our findings suggest that the surface molecules identified by these two monoclonal antibodies play a significant role in neutrophil activation by both FMLP and PMA.  相似文献   
996.
Immunogenic nature of a Pol gene product of HTLV-III/LAV   总被引:5,自引:0,他引:5  
The present studies were initiated to define the coding region of a 34 kilodalton (kd) protein (p34) frequently observed with antibodies from HTLV-III/LAV-infected people by immunoblotting and radioimmunoprecipitation (RIP) techniques. We have directly mapped this viral protein to the pol gene of HTLV-III/LAV by radiolabeled amino acid sequence analysis. This region at the 3' end of the pol gene is predicted to encode the endonuclease/integrase of the virus. The seroprevalence rate of antibodies to the pol gene products p64 and p53 and to the endonuclease p34 were evaluated. Of 161 HTLV-III/LAV seropositive people tested by immunoblotting procedures, greater than 98% had antibodies which reacted to p64/p53 and 92.6% reacted to p34 indicating that these viral proteins are highly immunogenic in nature. We have also analyzed the serum of nine healthy people living in West Africa who were infected with HTLV-IV, a closely related retrovirus. Nine of nine seropositive people had antibodies that cross-reacted to p34 of HTLV-III/LAV, whereas only seven of nine reacted to p64/p53. These studies and our earlier observations indicate that current diagnostic procedures for screening for HTLV-III/LAV infection may also detect HTLV-IV seropositive individuals, pointing to a need for more specific assay systems.  相似文献   
997.
998.
Wang  R; McFarland  JG; Kekomaki  R; Newman  PJ 《Blood》1993,82(11):3386-3391
A new platelet alloantigen, termed CA, has recently been implicated in a case of neonatal alloimmune thrombocytopenia (NATP) in a Filipino family in Canada. Maternal anti-CA serum reacted with glycoprotein (GP) IIIa and maintained its reactivity after removal of high mannose carbohydrate residues from GPIIIa. The monoclonal antibody (MoAb) AP3 partially blocked binding of anti-CA to GPIIIa, suggesting that the CA polymorphism is proximal to the AP3 epitope. Platelet RNA polymerase chain reaction (PCR) was used to amplify the region of GPIIIa cDNA that encodes this region of the protein. DNA sequence analysis showed a G<==>A nucleotide substitution at base 1564 that results in an arginine (Arg) (CGG)<==>glutamine (Gln) (CAG) polymorphism in amino acid (AA) 489. Further analysis of PCR-amplified genomic DNA from 27 normal individuals showed that AA 489 is encoded by a mutational "hot spot" of the GPIIIa gene, as three different codons for the wild-type Arg489 of GPIIIa were also found. The codon usage for Arg489 was found to be: CGG (63%), CGA (37%), and CGC (< 1%). These frequency data were valuable in determining the relationship of the CA alloantigen to the serologically defined TU GPIIIa polymorphism that is present in low frequency in the Finish population. Analyses of PCR-amplified genomic DNA showed the CA and TU alloantigens to be identical at the molecular level. Definition of these new molecular variants of the beta 3 integrin chain should prove valuable in the diagnosis of NATP in these two geographically disparate populations, and it may also provide useful genetic markers for examining other pathologic variations of the GPIIb-IIIa complex.  相似文献   
999.
Hematologic effects of flt3 ligand in vivo in mice   总被引:10,自引:7,他引:10  
We have investigated the effects of in vivo treatment with flt3 ligand (FL) on murine hematopoiesis, including mobilization of progenitors into the peripheral blood (PB). Mice were injected once daily with 10 micrograms recombinant human FL for 15 days. On days 3, 5, 8, 10, 15, and 22, mice were killed and analyzed for the number of leukocytes and colony-forming units (CFU) in bone marrow (BM), spleen, and PB. Splenic and PB cellularity increased with time in FL-treated mice. In the spleen, there was an increase in B cells, myeloid cells, and nucleated erythroid cells; in the PB, there was an increase in lymphocytes, granulocytes, and monocytic cells. The maximal number of CFU in the BM was observed after 3 days of FL treatment, giving 3.7- and 7.3-fold increases in CFU-granulocyte-macrophage (CFU-GM) and CFU-granulocyte, erythrocyte, monocyte, megakaryocyte (CFU-GEMM), respectively, compared with mouse serum albumin (MSA)-treated controls. After 8 days of FL treatment, there was a maximal 123- and 108-fold increase in splenic CFU-GM and CFU-GEMM, respectively. The maximal number CFU-GM and CFU- GEMM were seen in PB on day 10, with 537- and 585-fold increases, respectively. Burst-forming units-erythroid (BFU-E) increased in the same time frame as those of CFU-GM and CFU-GEMM in BM, spleen, and PB, although the magnitude was not as great. Primitive day-13 CFU-spleen (CFU-S) and phenotypically defined stem cells were also mobilized into the PB of FL-treated mice with similar kinetics and magnitude to that of CFU-GM and CFU-GEMM. We conclude from these studies that FL, when administered as a single agent, is a potent mobilizer of hematopoietic progenitors into the PB.  相似文献   
1000.
D'Andrea  AD; Szklut  PJ; Lodish  HF; Alderman  EM 《Blood》1990,75(4):874-880
We have generated four high affinity monoclonal antibodies (MoAbs) to recombinant human erythropoietin (EPO). All four MoAbs immunoprecipitate radioiodinated native EPO, and the concentrations of MoAbs required for maximum binding range from 10 nmol/L to 100 nmol/L. Two MoAbs, designated Group I MoAbs, bind to an epitope within the N- terminal 20 amino acids of EPO and also immunoprecipitate sodium dodecyl sulfate (SDS)-denatured EPO. Two other MoAbs (Group II MoAbs) do not immunoprecipitate SDS-denatured EPO and do not bind to any of the eight endo C fragments of EPO. We first used murine erythroleukemia (MEL) cells to test the MoAbs for inhibition of EPO-receptor binding. MEL cells, although unresponsive to EPO, express 760 high affinity receptors for EPO per cell (Kd = 0.24 nmol/L). To assay our MoAbs, MEL cells were grown as monolayers on fibronectin-coated Petri dishes and incubated at 4 degrees C with radioiodinated EPO. Group I MoAbs do not inhibit binding of radioiodinated EPO to the MEL EPO-receptor, but Group II MoAbs do inhibit binding in a dose-dependent manner. We next examined the neutralization of EPO bioactivity by our MoAbs, using EPO- dependent cell line. Only Group II MoAbs inhibit a newly developed EPO- dependent cell growth, demonstrating that inhibition of EPO-receptor binding correlates with neutralization of EPO bioactivity.  相似文献   
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