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21.
Syed Shamsuddin Qadri 《Parasitology research》1962,21(6):517-520
Summary A new species of Myxosporidia, Thelohanellus andhrae sp. n., is described from an Indian fish Labeo fimbriatus. Its chief differential characters are as follows: (a) in the elongated pyriform spore the anterior end is flat, (b) the polar capsule lying in the anterior portion also has a flat anterior surface, and (c) the distal part of the polar filament is whip-like.With 7 Figures in the Text 相似文献
22.
Rivera M Merlin S Hoda RS Gopalan A Hoda SA 《International journal of surgical pathology》2004,12(4):301-306
Sentinel lymph node biopsy has attained "standard of care' status in the management of breast carcinoma. However, the pathological interpretation and clinical consequences of "minimally involved' sentinel lymph nodes remain controversial. Herein, we present some of the complex and challenging pathological problems inherent in this evolving setting. Clearly, at least some of our current concepts regarding "minimally involved' sentinel lymph nodes need reappraisal. 相似文献
23.
Xainli J Cole-Tobian JL Baisor M Kastens W Bockarie M Yazdani SS Chitnis CE Adams JH King CL 《Infection and immunity》2003,71(5):2508-2515
Erythrocyte invasion by Plasmodium vivax is completely dependent on binding to the Duffy blood group antigen by the parasite Duffy binding protein (DBP). The receptor-binding domain of this protein lies within a cysteine-rich region referred to as region II (DBPII). To examine whether antibody responses to DBP correlate with age-acquired immunity to P. vivax, antibodies to recombinant DBP (rDBP) were measured in 551 individuals residing in a village endemic for P. vivax in Papua New Guinea, and linear epitopes mapped in the critical binding region of DBPII. Antibody levels to rDBP(II) increased with age. Four dominant linear epitopes were identified, and the number of linear epitopes recognized by semi-immune individuals increased with age, suggesting greater recognition with repeated infection. Some individuals had antibodies to rDBP(II) but not to the linear epitopes, indicating the presence of conformational epitopes. This occurred in younger individuals or subjects acutely infected for the first time with P. vivax, indicating that repeated infection is required for recognition of linear epitopes. All four dominant B-cell epitopes contained polymorphic residues, three of which showed variant-specific serologic responses in over 10% of subjects examined. In conclusion, these results demonstrate age-dependent and variant-specific antibody responses to DBPII and implicate this molecule in partial acquired immunity to P. vivax in populations in endemic areas. 相似文献
24.
ELISA versus routine tests in the diagnosis of patients with systemic and neurobrucellosis 总被引:4,自引:0,他引:4
G F Araj A R Lulu M I Khateeb M A Saadah R A Shakir 《APMIS : acta pathologica, microbiologica, et immunologica Scandinavica》1988,96(2):171-176
Sera from patients in different stages of brucellosis as well as sera and cerebrospinal fluid (CSF) from patients with central nervous system (CNS) brucellosis and controls, were tested by ELISA for Brucella-specific IgG, IgM and IgA. The results were compared with culture findings, micro-agglutination (MA), slide agglutination with Rose Bengal (RB), and Brucella melitensis stained antigens (SA). In sera of patients with acute brucellosis (296), ELISA was positive for IgM (100%), IgG (97%) and IgA (98%), and comparable results were found in sera of patients with subacute brucellosis (44): IgG (100%), IgM (86%) and IgA (100%). However, in patients with chronic brucellosis (40), IgG and IgA were consistently positive (100%) while IgM was only positive in 33% of their sera. The MA and RB showed similar results, being more positive in patients with acute (98%) and subacute (84%) than in chronic (61%) brucellosis. The SA and culture showed significantly lower positive results. In the CSF of patients with CNS brucellosis (45), ELISA was positive in 100%, 20% and 85% for IgG, IgM and IgA, respectively, compared to 13% positive by culture, 25% by MA and 22% by RB. ELISA was negative in the CSF specimens from patients with brucellosis without CNS involvement (66), or meningitis other than Brucella (62), and no meningitis (144). Thus, ELISA with its IgG, IgM and IgA profiles is the test of choice in the diagnosis of patients with brucellosis, especially those with chronic or CNS infection. 相似文献
25.
Shakir YA Samsioe G Nerbrand C Lidfeldt J;Women's Health in the Lund Area study 《Menopause (New York, N.Y.)》2004,11(5):549-555
OBJECTIVE: To delineate the influence of hormone therapy (HT) on features of metabolic syndrome with special reference to the composition and mode of administration of three specific HT regimens, all containing estradiol (E2) + norethisterone. DESIGN: The Women's Health in the Lund Area project screened all women (n = 10,766), born between 1935 and 1945. Complete data were obtained from 6,917 women. Those at or above defined cutoff limits were considered positively screened (n = 3,593) for metabolic syndrome. All of them were invited to undergo an oral glucose tolerance test; 2,923 women accepted. After excluding 200 women with impaired fasting glucose, 2,723 women were included in the present analysis. Serum lipids were determined by conventional standard methods at the department of clinical chemistry of Lund University Hospital. RESULTS: According to World Health Organization criteria, 2,123 women had normal glucose tolerance and 600 women had impaired glucose tolerance (IGT). IGT was less common (P = 0.001) among users of a transdermal patch [CYC-TRANS; E2 50 microg + norethisterone acetate (NETA) 250microg] compared with the two-combined oral regimen [CON-O (continuous oral E2 2 mg + NETA 1 mg) + CYC-O (sequential oral E2 2 mg + NETA 1 mg)]. Furthermore, IGT was more common among CON-O users when compared with either the CYC-O + CYC-TRANS group (P = 0.002) or the CYC-TRANS only group (P = 0.001). There were no significant differences between CYC-O versus CYC-TRANS or CON-O. Serum levels of total cholesterol were higher in the CYC-TRANS group than in the combined CON-O + CYC-O group (P < 0.05); they also were higher (P = 0.05) when comparing the CYC-O + CYC-TRANS versus CON-O as well as higher in CYC-TRANS versus CON-O (P < 0.05). Serum high-density lipoprotein cholesterol levels were higher in the CYC-O (P = 0.001), CYC-TRANS (P < 0.05), and the CYC-O + CYC-TRANS (P = 0.001) groups when compared with the CON-O users. There were no differences in the mean age, blood pressure (systolic and diastolic), body mass index, waste-hip ratio, or the rate of cigarette and alcohol consumption between the different hormone regimens. CONCLUSION: The risk of having a pathological glucose load was lower in transdermal versus oral users of HT. Transdermal HT could be regarded as first-line treatment in women at risk of developing diabetes. 相似文献
26.
Qu CF Song EY Li Y Rizvi SM Raja C Smith R Morgenstern A Apostolidis C Allen BJ 《Clinical & experimental metastasis》2005,22(7):575-586
Purpose: The urokinase plasminogen activator (uPA) and its receptor (uPAR) are expressed by pancreatic cancer cells and can be targeted
by the plasminogen activator inhibitor type 2 (PAI2). We have labeled PAI2 with 213Bi to form the alpha conjugate (AC), and have studied its in vitro cytotoxicity and in vivo efficacy.
Methods and Materials: The expression of uPA/uPAR on pancreatic cell lines, human pancreatic cancer tissues, lymph node metastases, and mouse xenografts
were detected by immunohistochemistry, confocal microscopy, and flow cytometry. Cytotoxicity was assessed by the MTS and TUNEL
assay. At 2 days post-cancer cell subcutaneous inoculation, mice were injected with AC by local or systemic injection.
Results: uPA/uPAR is strongly expressed on pancreatic cancer cell lines and cancer tissues. The AC can target and kill cancer cells
in vitro in a concentration-dependent fashion. Some 90% of TUNEL positive cells were found after incubation with 1.2 MBq/ml of AC.
A single local injection of ~222 MBq/kg 2 days post-cell inoculation can completely inhibit tumor growth over 12 weeks, and
an intraperitoneal injection of 111 MBq/kg causes significant tumor growth delay.
Conclusions: 213Bi-PAI2 can specifically target pancreatic cancer cells in vitro and inhibit tumor growth in vivo. 213Bi-PAI2 may be a useful agent for the treatment of post-surgical pancreatic cancer patients with minimum residual disease. 相似文献
27.
28.
Association of TNF-beta polymorphism with disease severity among patients infected with hepatitis C virus 总被引:2,自引:0,他引:2
Goyal A Kazim SN Sakhuja P Malhotra V Arora N Sarin SK 《Journal of medical virology》2004,72(1):60-65
The pathogenesis of chronic hepatitis C virus (HCV) infection remains unclear. Tumour necrosis factor alpha (TNF-alpha) is alleged to contribute in the pathogenesis of chronic HCV infection. Single nucleotide polymorphism in TNF-alpha and -beta genes could influence the outcome of HCV infection. The aim was to study single nucleotide polymorphism in TNF-alpha promoter region and Nco I polymorphisms in the TNF-beta gene in patients with chronic hepatitis C. Fifty-two patients with histologically proven chronic hepatitis, who had raised ALT levels (>1.5 x ULN) and were HCV RNA positive, were studied. Genotyping of -308 promoter variant of TNF-alpha was performed by PCR with primers that incorporated an Nco I restriction site. For PCR typing of the TNF-beta Nco I restriction fragment length polymorphism, sequence specific primers were used. Polymorphism in the TNF-alpha G/G, G/A and A/A allele was not different between HCV patients and healthy controls. TNF-beta A/A allele was significantly more common (P = 0.02) in patients (28.8%) as compared to controls (12.8%), whereas no significant difference was observed for TNF-beta G/A and G/G alleles [corrected]. Nco I TNF-beta A/A was strongly associated with -308 TNF-alpha G/G (RR of HCV persistence = 4.9), indicating possible linkage between TNF-beta A/A and TNF-alpha G/G allele. Patients with severe hepatic fibrosis more frequently had the TNF-beta A/A allele as compared to patients with mild disease (P = 0.04). Immunogenetic factors, such as single nucleotide polymorphisms in TNF-beta (A/A allele), may affect the natural course of HCV infection, in particular, the disease progression. Larger studies including cytokine expression profiles are needed to fully understand the contribution of the polymorphisms described in the pathogenesis of chronic hepatitis C. 相似文献
29.
30.
Özcan Özdamar Rafael E. Delgado Syed Rahman Carlos Lopez 《Annals of biomedical engineering》1998,26(5):883-891
An innovative acoustic noise canceling method using adaptive Wiener filtering (AWF) was developed for improved acquisition of distortion product otoacoustic emissions (DPOAEs). The system used one microphone placed in the test ear for the primary signal. Noise reference signals were obtained from three different sources: (a) pre-stimulus response from the test ear microphone, (b) post-stimulus response from a microphone placed near the head of the subject and (c) post-stimulus response obtained from a microphone placed in the subjects nontest ear. In order to improve spectral estimation, block averaging of a different number of single sweep responses was used. DPOAE data were obtained from 11 ears of healthy newborns in a well-baby nursery of a hospital under typical noise conditions. Simultaneously obtained recordings from all three microphones were digitized, stored and processed off-line to evaluate the effects of AWF with respect to DPOAE detection and signal-to-noise ratio (SNR) improvement. Results show that compared to standard DPOAE processing, AWF improved signal detection and improved SNR. © 1998 Biomedical Engineering Society.
PAC98: 4364Jb, 4360-c, 8790+y 相似文献