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81.
目的:考察甲壳胺对不同性质药物的适应性。方法:选择了盐酸麻黄碱,盐酸心得安,卡马西平,磺胺嘧啶,阿司匹林,法莫替丁,朴热息痛,潘生丁,茶碱,炎痛喜康,水杨酸等不同性质的11种药物,以甲胺为阻滞剂,制备了缓释型骨架片溶出效果。结果:甲壳胺的缓释作用随药物碱性增强,分子量增大,溶解度降低而增强,结论:甲 胺对不同性质的药物均有一定缓释作用。 相似文献
82.
Kalyne Kelly Negromonte Gonalves Marcelo Soares dos Santos Davi da Silva Barbirato Caio Csar Gonalves Silva Allan Vinícius Martins de Barros Emerllyn Shayane Martins de Araújo Renata de Albuquerque Cavalcanti Almeida Belmiro Cavalcanti do Egito Vasconcelos 《Medicina oral, patología oral y cirugía bucal》2022,27(6):e560
Background Third molar extraction is among the most common surgical procedures performed by oral-maxillofacial surgeons. Postoperative pain, swelling and trismus are common, especially in wisdom teeth, due to trauma to local tissues and the duration of the surgical procedure, among other factors.Material and Methods This systematic review was conducted in accordance with the ‘Preferred Reporting Items for Systematic Reviews and Meta-Analyses’ in order to answer the focused question: ‘Is the local submucosal injection of tramadol effective at the control of postoperative pain in patients submitted to impacted mandibular third molar extractions?’. We analyzed papers published until March 30, 2021 in the MEDLINE|PubMed, Web of Science and Cochrane Library databases. Gray literature was also consulted. Standard pairwise meta-analyses of direct comparisons were performed using a fixed-effect model; I2 ≥ 50 % or ≥ 75 % indicated moderate or high heterogeneity, respectively. Risk of bias was assessed by Cochrane Collaboration’s tool.Results In total, 172 participants (98 males and 74 females, aged 18 or over) from three randomized placebo-controlled trials were considered for analysis. The submucosal injection of 2 ml of tramadol adjacent to the impacted mandibular third molar was effective in controlling pain up to 6-hours after surgery, in increasing the onset of consumption of rescue analgesic and in reducing the total number of rescue analgesics used.Conclusions The submucosal injection of tramadol can be considered a safe and effective procedure for pain control after impacted mandibular third molar extractions. Key words:Tramadol, impacted teeth, third molars, postoperative pain, adverse effects. 相似文献
83.
Successful complete hematopoietic reconstitution (CHR) using nonleukemic peripheral stem cells (PSC) after marrow ablation has been reported in animals but not man. Previous studies of cytapheresis products from humans, as a prelude to use for CHR, have documented the presence of committed myeloid (CFU-GM) and erythroid (BFU-E) precursors. We have examined mononuclear cell (MNC) products collected on the Fenwal CS3000 Blood Cell Separator for these plus the more primitive mixed (granulo-, erythro-, mono-, and megakaryocytic) cell colony-forming units (CFU-GEMM) and for various lymphocytic subpopulations (LSP). One to two-hour products contained 36 +/- 7 CFU- GEMM/10(6) MNC (mean +/- SE, n = 8) or 490 +/- 131/ml product. This compared favorably with blood (23 +/- .4/10(6) MNC or 46 +/- 8/ml, n = 14) and bone marrow (146 +/- 58/10(6) MNC, n = 12). Collection efficiency for E-rosette-positive cells approximated that for total lymphocytes and was variable for other LSP. Recovery of CFU-GEMM after freezing in 10% dimethylsulfoxide at a controlled rate and storage in liquid N2 was 54% +/- 8% (n = 8). Cytapheresis collection of large numbers of pluripotent hematopoietic precursors and demonstration of adequate recovery of these after cryopreservation, both previously unreported, are significant steps toward eventual CHR using nonleukemic PSC. 相似文献
84.
LC Ewan PJ Charleston SH Pettit 《Annals of the Royal College of Surgeons of England》2014,96(2):e9-e10
Perineal hernia is a rare complication following laparoscopic abdominoperineal resection (APR) for rectal cancer. We present two case reports of perineal hernia following laparoscopic APR and discuss their management. We suggest that they developed because the pelvic peritoneum was left open during laparoscopic APR and propose that closure of the pelvic peritoneum should be routine in this operation. 相似文献
85.
SolEmuls® Technology: A Way to Overcome the Drawback of Parenteral Administration of Insoluble Drugs
J.-U. Junghanns I. Buttle R.H. Müller I.B. Araújo A.K.A. Silva E.S.T. Egito 《Pharmaceutical development and technology》2013,18(5):437-445
In this article, a nanosuspension of AmB was prepared and mixed with the preformed parenteral emulsion Lipofundin® and subjected to high-pressure homogenization (SolEmuls® technology). Characterization was performed by photon correlation spectroscopy (PCS), laser diffractometry (LD), and zeta potential measurements. Drug incorporation was studied by using light microscopy. The produced emulsions were further investigated by comparing them with the commercially available Fungizone® in regard to antifungal efficiency and toxicity. Results suggest that through the SolEmuls® process the AmB forms a reservoir, out of which it is released in such a manner that it is more efficient and less toxic than Fungizone®. 相似文献
86.
Serum hepatitis B surface antigen correlates with fibrosis and necroinflammation: A multicentre perspective in China 下载免费PDF全文
P. Zhang HB. Du GD. Tong XK. Li XH. Sun XL. Chi YF. Xing ZH. Zhou Q. Li B. Chen H. Wang L. Wang H. Jin DW. Mao XB. Wang QK. Wu FP. Li XY. Hu BJ. Lu ZY. Yang MX. Zhang WB. Shi Q. He Y. Li KP. Jiang JD. Xue XD. Li JM. Jiang W. Lu GJ. Tian ZB. Hu JC. Guo CZ. Li X. Deng XL. Luo FY. Li XW. Zhang YJ. Zheng G. Zhao LC. Wang JH. Wu H. Guo YQ. Mi ZJ. Gong CB. Wang F. Jiang P. Guo XZ. Yang WQ. Shi HZ. Yang Y. Zhou NN. Sun YT. Jiao YQ. Gao DQ. Zhou YA. Ye 《Journal of viral hepatitis》2018,25(9):1017-1025
The kinetics of serum hepatitis B surface antigen (HBsAg) during the natural history of hepatitis B virus (HBV) infection has been studied, but the factors affecting them remain unclear. We aimed to investigate the factors affecting HBsAg titres, using data from multicentre, large‐sized clinical trials in China. The baseline data of 1795 patients in 3 multicentre trials were studied, and the patients were classified into 3 groups: hepatitis B early antigen (HBeAg)‐positive chronic HBV infection (n = 588), HBeAg‐positive chronic hepatitis B (n = 596), and HBeAg‐negative chronic hepatitis B (n = 611). HBsAg titres in the different phases were compared, and multiple linear progression analyses were performed to investigate the implicated factors. HBsAg titres varied significantly in different phases (P = .000), with the highest (4.60 log10 IU/mL [10%‐90% confidence interval: 3.52 log10 IU/mL‐4.99 log10 IU/mL]) in patients with HBeAg‐positive chronic HBV infection. In all phases, age and HBV DNA were correlated with serum HBsAg level. In HBeAg‐positive chronic hepatitis B patients, a negative correlation between HBsAg titres and fibrosis stage was observed. Alanine amonitransferase or necroinflammatory activity was also correlated with HBsAg titres in HBeAg‐negative chronic hepatitis B patients. In conclusion, decreased HBsAg titres may be associated with advancing fibrosis in HBeAg‐positive chronic hepatitis B patients or increased necroinflammation in those with HBeAg‐negative chronic hepatitis B. Our findings may help clinicians better understand the kinetics of HBsAg and provide useful insights into the management of this disease. 相似文献
87.
P. Zhang HB. Du GD. Tong XK. Li XH. Sun XL. Chi YF. Xing ZH. Zhou Q. Li B. Chen H. Wang L. Wang H. Jin DW. Mao XB. Wang QK. Wu FP. Li XY. Hu BJ. Lu ZY. Yang MX. Zhang WB. Shi Q. He Y. Li KP. Jiang JD. Xue XD. Li JM. Jiang W. Lu GJ. Tian ZB. Hu JC. Guo CZ. Li X. Deng XL. Luo FY. Li XW. Zhang YJ. Zheng G. Zhao LC. Wang JH. Wu H. Guo YQ. Mi ZJ. Gong CB. Wang F. Jiang P. Guo XZ. Yang WQ. Shi HZ. Yang Y. Zhou NN. Sun YT. Jiao YQ. Gao DQ. Zhou YA. Ye 《Journal of viral hepatitis》2018,25(9):ii-ii
88.
The degradation of fibrillar type II collagen is a major feature of
cartilage destruction in rheumatoid arthritis (RA). Since collagenase 3 is
produced by chondrocytes and preferentially degrades type II cartilage
collagen, it seemed likely that this enzyme would have a prominent role in
the destruction of rheumatoid joints. Using immunolocalization techniques,
we have examined and compared the production and distributions of
collagenase 1 and collagenase 3 in cells and tissues derived from
rheumatoid knee arthroplasties. Primary cultures of chondrocytes stimulated
with interleukin-1 beta showed that most of the cells produced collagenase
1, whereas only a minority (approximately 5-10%) produced collagenase 3; a
few chondrocytes demonstrated the co-ordinate production of both enzymes.
Primary cultures of rheumatoid synoviocytes produced collagenase 1, but not
collagenase 3. Both enzymes were demonstrated in the rheumatoid lesion.
Collagenase 1 was more commonly observed in both synovium and cartilage (22
of the 28 specimens), was especially prominent at cartilage erosion sites,
and most of the positive specimens demonstrated extracellular enzyme. By
contrast, collagenase 3 was observed less frequently (7/28 specimens) and
was produced by relatively few chondrocytes and synovial cells, this
usually being much less than that observed for chondrocytes of
osteoarthritic cartilage. These observations suggest different regulatory
mechanisms for the production of collagenases 1 and 3 in the rheumatoid
lesion, and demonstrate that the distribution and production of collagenase
1 are far more prevalent than those for collagenase 3.
相似文献
89.
Independent prognostic significance of a nuclear proliferation antigen in diffuse large cell lymphomas as determined by the monoclonal antibody Ki-67 总被引:12,自引:0,他引:12
Grogan TM; Lippman SM; Spier CM; Slymen DJ; Rybski JA; Rangel CS; Richter LC; Miller TP 《Blood》1988,71(4):1157-1160
To assess the prognostic significance of the growth fraction in diffuse large cell lymphoma (DLCL), we studied 105 DLCL patients with the monoclonal antibody Ki-67 applied to frozen tissue sections. Ki-67 detects a nuclear antigen associated with cell proliferation not found in resting cells. Ki-67 findings and other clinical prognostic factors were correlated with outcome using univariate and multivariate analyses in the proportional hazards model. High proliferative activity, defined as nuclear Ki-67 expression in greater than 60% of malignant cells (Ki- 67 greater than 60), was found to be a strong predictor of poor survival among these patients (P = .003, log-rank). The 19 patients with Ki-67 greater than 60% had a median survival of 8 months compared with a median survival of 39 months for the 86 patients with Ki-67 less than or equal to 60%. Examination of pretreatment clinical variables indicated the patient groups were similar with regard to age, sex, stage, B symptoms, tumor bulk, and lactate dehydrogenase (LDH). Both patient groups received comparable curative intent therapy and showed comparable complete response rate precluding treatment differences as modifying outcome. Multivariate analysis indicated Ki-67 is an independent predictor of survival (multivariate P = .006). Further statistical analysis using only B-cell DLCL patients treated with CHOP (63 patients) indicated that Ki-67 greater than 60 retained strong prediction of poor outcome (P = .002, log-rank) among this homogeneous group. We conclude that high proliferative activity (Ki-67 greater than 60) is an independent factor allowing laboratory prediction of probable poor outcome of DLCL. 相似文献
90.
Enhanced expression of transforming growth factor beta during megakaryoblastic differentiation of K562 leukemia cells 总被引:5,自引:0,他引:5
Platelet alpha granules contain several growth factors such as the transforming growth factor beta (TGF-beta) that are released during blood clotting and are thought to participate in the repair of tissue injury; however, the site of synthesis of platelet TGF-beta has not been demonstrated. We studied TGF-beta expression during megakaryoblastic differentiation of the chronic myeloid leukemia cell line K562 in vitro. These cells have mainly erythroid characteristics but acquire several megakaryoblastic properties when treated with the phorbol diester 12-0-tetradecanoyl-13-phorbolacetate (TPA). During four subsequent days of megakaryoblastic differentiation the amount of the 2.5-kilobase (kb) TGF-beta mRNA increased about eightfold, and a novel 2.3-kb mRNA species was induced in the K562 cells. This occurred concomitantly with distinct induction patterns of platelet-derived growth factor A (PDGF-A) and c-sis (PDGF-B chain) RNAs and several platelet antigens. The expression of erythroid markers such as glycophorin A decreased. Culture media of TPA-differentiated K562 cells also contained TGF-beta polypeptides as shown by a sensitive radioreceptor assay and by immunoprecipitation after metabolic labeling of the cells. These polypeptides were not seen in culture media from dimethyl sulfoxide- or sodium butyrate-treated cells. Unlike in several other cells, exogenously added TGF-beta 1 or 2 affected neither TGF- beta nor PDGF RNA expression in K562 cells. 相似文献