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61.
Rheumatoid arthritis (RA) is a systemic autoimmune disease that is associated with immunologic alterations in T cells and
B cells. Moreover, many of the agents used in RA patients are potentially immunosuppressive. Thus, the underlying disease
and treatment may both increase the susceptibility to infections and decrease vaccine responses. With the growing use of aggressive
therapies for RA, including anti-tumor necrosis factor agents and newer biologic therapies such as rituximab and abatacept,
an increasing concern will be that patients may not respond to conventional vaccination. Further prospective studies on response
to vaccination are needed to answer this important public health question. Nevertheless, it is already clear that vaccination
does induce response in many patients. Unfortunately, vaccination is underutilized in RA patients and needs to be aggressively
promoted. 相似文献
62.
Expression of a Mr 32,000 laminin-binding protein messenger RNA in human colon carcinoma correlates with disease progression 总被引:4,自引:0,他引:4
Cell surface receptors for laminin may play an important role in tumor migration and metastasis. To evaluate laminin receptor/laminin-binding protein expression in human colon carcinoma, surgical specimens of primary colon cancers and liver metastases were examined by blot hybridization of total RNA with a complementary DNA clone which encodes a Mr 32,000 human laminin-binding protein. The mRNA level of the laminin-binding protein was higher in primary colon carcinoma than in adjacent normal colonic epithelium in 20 of 21 cases. In all 6 cases of colon cancer liver metastases, the laminin-binding protein mRNA level was more than 3-fold greater in tumor than in adjacent normal liver tissue. The tumor/normal ratio of this laminin-binding protein mRNA expression in primary colon cancer has significant correlation with Dukes' classification (P less than 0.001). Our results suggest that mRNA expression of the laminin-binding protein may be a marker of human colorectal cancer progression and biological aggressiveness. 相似文献
63.
Manickam Ravikumar Ramamoorthy Ravichandran Saminathan Sathiyan Sanjay Sudhakar Supe 《Strahlentherapie und Onkologie》2004,180(3):173-178
PURPOSE: To analyze backscattered dose enhancements near different metallic interfaces for cobalt-60 ((60)Co) gamma rays and 6- and 18-MV photon beams. MATERIAL AND METHODS: Measurements were carried out with a PTW thin-window, parallel-plate ionization chamber and an RDM-1F electrometer. Thin sheets of aluminum, mild steel, copper, cadmium and lead were used as inhomogeneities. The chamber was positioned below the inhomogenities with the gantry maintained under the couch. RESULTS: It can be noticed that the backscatter dose factor (BSDF) reaches the saturation value within few millimeters of all inhomogeneities and the thickness at which the saturation value is reached depends on the atomic number of the inhomogeneity. The amount of backscattered radiation was noticed to be greater with lesser-energy photons ((60)Co) compared to the high erenergy photons. The BSDF varies across the beam when the inhomogeneity is present due to the change in beam quality. The backscattered electrons from lead inhomogeneity have a range in the order of 5-7 mm. CONCLUSION: Higher atomic number inhomogeneities result in an increase in BSDF, as they have higher scattering cross section for the secondary electrons. The increase in dose was noticed for few millimeters upstream from the metallic inhomogeneity, which suggests that the range of backscattered electrons is very small. Since the factors affecting the BSDF at the interface are energy dependent, it is expected that the variation in BSDF will also be sensitive to the beam energy. 相似文献
64.
65.
A. Anand Babu Christus P. Panneerselvam A. Ravikumar M. Marieeswaran S. Sivanesan 《RSC advances》2019,9(8):4268
A novel colorimetric sensing platform using the peroxidase mimicking activity of ternary MoS2-loaded ZnO–g-C3N4 nanocomposites (ZnO–g-C3N4/MoS2) has been developed for the determination of Hg(ii) ions over co-existing metal ions. The nanocomposite was prepared using an exfoliation process, and the product was further characterized using SEM, TEM, XRD and FTIR analysis. The ZnO–g-C3N4/MoS2 possesses excellent intrinsic catalytic activity to induce the oxidation of 3,3′,5,5′-tetramethylbenzidine (TMB) in aqueous solution in the presence of H2O2 to generate deep blue coloured cation radicals (TMB+) which can be viewed with the naked eye and produce absorbance at a wavelength of 652 nm. The addition of a well known bioradical scavenger, glutathione (GSH), to the solution hinders the generation of cation radicals and turns the solution colourless. The introduction of Hg(ii) to this solution brings the blue colour back into it, due to the strong affinity of the thiol in the GSH. Based on this mechanism, we have developed a simple and rapid colorimetric sensor for the highly sensitive and selective detection of Hg(ii) ions in aqueous solution with a low detection limit of 1.9 nM. Furthermore, the prepared colorimetric sensor was effectively applied for the quantification analysis of real water samples.A novel colorimetric sensing platform using the peroxidase mimicking activity of ternary MoS2-loaded ZnO–g-C3N4 nanocomposites (ZnO–g-C3N4/MoS2) has been developed for the determination of Hg(ii) ions over co-existing metal ions. 相似文献
66.
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68.
Shailesh Ernest Gokavi Ravikumar Jadhav Purushotham Reddy 《Journal of minimally invasive gynecology》2013,20(2):259-261
Herein we report a rare case of a large uterine neurofibroma. The patient reported infertility and nonspecific pelvic symptoms. Physical examination and ultrasonography revealed a mass of uterine origin with echo texture similar to that of a myoma. With a provisional diagnosis of a myomatous uterus, laparoscopic myomectomy was attempted. The mass, which measured 13 × 9 × 8 cm, was noted to be arising from the uterine fundus and extending into the left broad ligament. Histopathologic examination revealed a neurofibroma, which was confirmed at immunohistochemical analysis of the specimen. Most neurofibromas arise as subcutaneous swellings, and large neurofibromas arising from the myometrium are rare. Deep-tissue neurofibromas are known to recur and are associated with a higher probability of becoming malignant. 相似文献
69.
Chemotherapy for Metastatic Melanoma during Pregnancy 总被引:1,自引:0,他引:1
Robert S. Dipaola M.D. Susan Goodin Pharm.D. Michelle Ratzell Pharm.D. Margaret Florczyk M.D. George Karp M.D. T.S. Ravikumar M.D. 《Gynecologic oncology》1997,66(3):526-530
Melanoma during pregnancy represents a difficult problem. Although surgery is a definitive therapy for early-stage disease, rapidly progressive metastatic disease in pregnancy requires a series of more difficult decisions. We report the use of combination chemotherapy with tamoxifen, carmustine, dacarbazine, and cisplatin in a patient with metastatic melanoma during the second trimester of pregnancy. The patient received 2 cycles of chemotherapy prior to delivery of a healthy 1520-g baby girl at 30 weeks gestation. Placental pathology, however, revealed malignant melanoma in the intervillous space and melanin pigment granules in villous Hofbauer cells and synctial trophoblasts. This report also reviews the literature, assessing the importance of pregnancy as a prognostic factor, the effects of metastasis on the products of conception, and the use of chemotherapy in pregnancy. We conclude that combination chemotherapy can be administered in the second trimester of pregnancy for the treatment of rapidly progressive melanoma without interfering with the successful maturation and delivery of an infant of 30 weeks gestation. 相似文献
70.
Prospective comparison of preoperative imaging and intraoperative ultrasonography in the detection of liver tumors 总被引:8,自引:0,他引:8
M P Clarke R A Kane G Steele E S Hamilton T S Ravikumar G Onik M E Clouse 《Surgery》1989,106(5):849-855
A prospective evaluation of the accuracy of preoperative computed tomography (CT), ultrasonography (US), and angiography was performed in 54 patients undergoing resection of hepatic neoplasms. The results were compared with surgical findings and intraoperative ultrasonography (IOUS). A total of 167 lesions was seen by means of IOUS, of which preoperative US enabled detection of 127 (76%). In 48 patients CT allowed detection of 91 of 150 lesions (61%), and in 35 patients angiography showed 56 of 107 lesions (52%). When the detection rate is analyzed according to hepatic segment, the greater overall accuracy of preoperative US may be attributed to a markedly better detection rate in lateral segment of the left lobe of the liver. Lesion size also represented a factor, with preoperative US allowing detection of a greater number of small (less than 2 cm) lesions compared with CT. In patients studied with both CT and US, the combined lesion-detection rate increased to 81% in the right lobe and 76% in the left lobe. Because of this we recommend that preoperative assessment include both CT and US evaluation of the liver. IOUS showed 25% to 35% additional lesions compared with preoperative US and CT. More importantly, 40% of the lesions demonstrated by IOUS were neither visible nor palpable at surgery. We recommend that IOUS be considered in all patients in whom resection of hepatic neoplasm is planned. 相似文献