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Objective: To analyze the prognostic factors and the influence of surgical margin to prognosis. Methods: A retrospective analysis was performed for 208 pelvic tumors who received surgical treatment from January 2000 to December 2017 in our instituition. Survival analysis was performed using the Kaplan-Meier method and Log rank test, and impact factor analysis was performed using Cox regression models. Results: There were 183 initial patients and 25 recurrent cases. According to Enneking staging, 110 cases were stage â B and 98 cases were stage â ¡B. 19 lesions were in zone â , 1 in zone â ¡, 15 in zone â ¢, 29 in zone â +â ¡, 71 in zone â ¡+â ¢, 29 in zone â +â £, 35 in zone â +â ¡+â ¢, 3 in zone â +â ¡+â £, and 6 in zone â +â ¡+â ¢+â £. Surgical margins including Intralesional excision in 7 cases, contaminated margin in 21 cases, marginal resection in 67 cases, and wide resection in 113 cases. Local recurrence occurred in 37 cases (17.8%), 25 cases were performed by reoperation and 12 cases received amputation finally. The 5-year recurrence rate of marginal resection was higher than wide resection (Pï¼0.05), and the recurrence-free survival rate of marginal resection was lower than wide resection (Pï¼0.05). There was significant differences in recurrence rate and recurrence-free survival rate between R0 and R1 resection (Pï¼0.05). 92 cases were not reconstructed and 116 cases were reconstructed after pelvic surgery. At the last follow-up, 63 patients (30.3%) died, and the 5-year, 10-year and 15-year survival rates were 70.4%, 66.8% and 61.3%, respectively. The 5-year survival rate of stage â B and â ¡B tumor was 90.4% and 46.8%, respectively. There were 29 cases had postoperative wound complications (13.8%), 1 case with pelvic organ injury. The final function was evaluated in 132 patients, with an average MSTS score of 25.1±3.6. Cox multivariate analysis showed that surgical staging, R0/R1 margin and metastasis were independent prognostic factors for pelvic tumors. Conclusions: The safe surgical margin is the key factor for recurrence-free of pelvic tumor. The survival rate of stage â ¡B pelvic tumors was significantly lower than that of stage â B tumors. Wound infection is the main postoperative complication. Surgical staging, R0/R1 margin and metastasis were independent prognostic factors of pelvic tumors.
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Neoplasias Ósseas , Margens de Excisão , Recidiva Local de Neoplasia , Ossos Pélvicos , Humanos , Estudos Retrospectivos , Ossos Pélvicos/cirurgia , Neoplasias Ósseas/cirurgia , Prognóstico , Taxa de Sobrevida , Estadiamento de Neoplasias , Modelos de Riscos Proporcionais , Feminino , Reoperação , Masculino , Neoplasias Pélvicas/cirurgia , Neoplasias Pélvicas/patologiaRESUMO
Objective: To explore the application of sentinel lymph node biopsy (SLNB) and its prognostic value in the treatment of acral melanoma. Methods: We retrospective analyzed 118 patients who underwent sentinel lymph node biopsy from Mar 2012 to Jun 2019 with effective follow-up data available in our institute. We ruled out palpable regional lymph node metastasis with preoperative imaging of MRI and ultrasonography, used the (99)Tc(m)-Dextran (Dx) as a tracer, with intraoperative γ-ray probe positioning for SLN capture. Wide resection and reconstruction in primary lesion followed by complete lymph node dissection were underwent SLN positive patients. Cox regression model were used to analyze the prognostic factors. Results: The patients had an average disease history of 53.6 months (2-360 months), the primary lesion located at hands and feet in 84 cases, while 27 cases were subungual and 7 cases were cutaneous. The mean Breslow depth was 3.6 mm, and 72 cases (61.0%) combined with ulceration. The average number of SLN was 2.8, the SLN positive rate was 24.6% (29/118), and the false-negative rate was 2.5% (3/118). There were 24 cases (20.3%) developed clinically positive metastasis, including 7 cases displayed distant metastasis combined with lymph node metastasis (5.9%), 8 cases with clinically positive lymph node metastasis alone (6.8%), and 9 cases with distant metastasis (7.6%). There were 33 patients in stage â , 56 patients in stage â ¡ and 29 patients in stage â ¢, with a 5-years overall survival rate of 69.5%. The Breslow depth is an independent risk factor of SLN positive. While Breslow depth, SLN status, SLN positive number and clinically detectable metastasis are independent prognostic factors of the overall survival (P<0.05). Conclusions: Patients without clinically positive regional lymph node metastasis under imaging and physical examinations, SLNB can provide accurate pathologic staging and play an accurate prediction role in the prognostic evaluation. SLNB should be carried out routinely in clinical practice.
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Melanoma , Linfonodo Sentinela , Neoplasias Cutâneas , Humanos , Excisão de Linfonodo , Linfonodos/diagnóstico por imagem , Linfonodos/cirurgia , Melanoma/diagnóstico por imagem , Melanoma/cirurgia , Prognóstico , Estudos Retrospectivos , Biópsia de Linfonodo Sentinela , Neoplasias Cutâneas/diagnóstico por imagem , Neoplasias Cutâneas/cirurgiaRESUMO
OBJECTIVE: Neurogenic hypertension is a type of hypertension characterized by increased sympathetic activity. Vascular compression is one of the pathogenic mechanisms of neurogenic hypertension. The sample sizes of currently available studies on MVD in the treatment of hypertension are small, and the results are considerably different. Therefore, we conducted a meta-analysis of the previous literature to obtain the most realistic efficiency and analyzed the current situation of MVD as a treatment option of the vascular compression type of neurogenic hypertension. METHOD: We systematically searched and identified relevant studies published before July 2019 from PubMed and Embase. Six studies involving 162 participants were included into our final analysis. RESULT: The data showed that the effective rate of MVD was 70.1% (95% CI: 0.602-0.801). The most common offending vessel was PICA (29.9%), followed by VA/BA (23.9%) and VA/BA plus PICA (12.7%). Complications were mostly related to the VII, VIII, IX, and/or X cranial nerve dysfunction. CONCLUSION: MVD as a treatment option of the vascular compression type of neurogenic hypertension is effective and safe. In spite of this conclusion, more prospective studies are needed to confirm it. On the other hand, a diagnostic method with higher sensitivity and specificity is necessary.
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Hipertensão , Cirurgia de Descompressão Microvascular , Espasmo Hemifacial/cirurgia , Humanos , Estudos Prospectivos , Resultado do Tratamento , Neuralgia do Trigêmeo/cirurgiaRESUMO
Melanoma is a malignant tumor derived from the skin and mucous membrane, the epidemiological data showed that the incidence of melanoma elevated rapidly in the last decade. Early lymph node metastasis is a distinguishing characteristic of melanoma. The assessment of regional lymph nodes is a vital factor for melanoma staging and comprehensive therapeutic strategies. The sentinel lymph node biopsy (SLNB) plays an important role in this comprehensive diagnosis and treatment system. Completion lymph node dissection (CLND) with positive sentinel lymph node was accepted by traditional theories. But it has recently been questioned via the latest global clinical trial. CLND limited the benefit for melanoma specific survival. However, SLNB is the reliable procedure for staging and prognostic evaluation of melanoma patients with positive sentinel lymph node, and CLND can significantly improve the local control and decrease the regional recurrence according to the evidence-based medicine. The authors summary the recently correlational research of SLNB and CLND in melanoma in this review.
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Excisão de Linfonodo/métodos , Melanoma/patologia , Melanoma/cirurgia , Biópsia de Linfonodo Sentinela/métodos , Neoplasias Cutâneas/patologia , Neoplasias Cutâneas/cirurgia , Humanos , Metástase Linfática , Recidiva Local de Neoplasia , Biópsia de Linfonodo Sentinela/tendênciasRESUMO
Objective: To evaluate the impact of surgery in pain relief, quality of life, neurological function, survival status and prognosis of spinal myeloma patients. Methods: Twenty spinal myeloma patients from January 1990 to June 2016 who underwent surgery were reviewed. Compare the preoperative and postoperative neurological function and quality of life, via visual analogue scale (VAS), Eastern Cooperative Oncology Group (ECOG) score and Frankel classification, survival rate based follow-up were statistical analyzed by Wilcoxon and Kaplan-Meier respectively, univariate and multivariate analysis with Cox regression model. Results: There were 12 males and 8 females enrolled with average age of 53.3 (range from 31 to 75 years). Lesions location distribution: cervical spine 1 case, 12 in thoracic spine, 6 in lumbar and 1 in sacral tumor. The majority of symptom was pain in 20 cases and 5 cases had incomplete paraplegia with spinal cord compression. Single posterior approach in 15 cases, single anterior in 3 cases, anterior and posterior combined approach in 2 cases. The average operation time was 225 min, average blood loss was 2 320 ml. The patients with postoperative median VAS score and ECOG score were 2.00 and 1 respectively, it is significantly decreased (P<0.001) compared with the preoperative score (7.50 and 3), the median Frankel classification was level 5 in postoperative patients and increased significantly (P<0.001) than preoperative patients (level 4). One patient had local recurrence, 2 patients had complications. The overall 5 and 10 year survival rate was 61.7% and 42.3%, respectively. The 3 years survival rate between surgery combine chemotherapy and without chemotherapy group was 87.1% and 25.0%, 5 years survival rate was 79.1% and 0 respectively (P<0.01). LDH, ALB and chemotherapy were independent prognostic factors of survival from Cox regression. The odds ratio (OR) was 1.037 (P=0.006), 0.746 (P=0.009) and 0.077 (P=0.012) respectively. Conclusion: Surgical strategy is effective to improve quality of life for spinal myeloma patients. Combine chemotherapy could improve the survival.
Assuntos
Mieloma Múltiplo/cirurgia , Neoplasias da Coluna Vertebral/cirurgia , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Mieloma Múltiplo/complicações , Mieloma Múltiplo/mortalidade , Procedimentos Neurocirúrgicos , Duração da Cirurgia , Medição da Dor , Período Pós-Operatório , Prognóstico , Qualidade de Vida , Estudos Retrospectivos , Compressão da Medula Espinal/etiologia , Neoplasias da Coluna Vertebral/complicações , Neoplasias da Coluna Vertebral/mortalidade , Taxa de Sobrevida , Resultado do TratamentoRESUMO
Objective: To compare the local recurrent rate, the persistence of reconstruction and functional recovery of Giant Cell Tumor (GCT) after the treatments of extensive curettage or resection. Methods: A retrospective review was conducted on the clinical data of 50 patients who had giant cell tumor with pathological tracture around the knee treated in our hospital from January 2001 to July 2014. There were 30 males and 20 females. The average age was 33.7 years respectively (range, 17 to 71 years). The fracture localizations of 45 cases were distal femur and of 5 cases were proximal tibia. According to AO fracture classification, 3 cases were in type A, 36 cases in type B and 11 cases in type C. In Campanicci system for image grading study, 5 cases were in grade â ¡ and 45 cases in grade â ¢. Surgical treatment included 20 cases of extensive curettage and 30 cases of resection. The surgical reconstructive methods included 16 cases of cement reconstruction with internal fixation, 5 cases of unicompartmental arthroplasty with allograft, 1 case of segment osteoarticular allograft transplantation and 28 cases of prosthesis replacement. Final statistical analysis of surgery and therapeutic effect were carried out by SPSS, version 16.0 for Windows. Enrolling parameters collected gender, age, location, fracture type, surgical treatment, surgical margin, reconstruction, complications, local recurrence (LR) and functional evaluation. Categorical data were described by result frequencies.The comparison of the rate was performed by chi-square or Fisher's exact test. Between the two groups compared using independent t-test. The recurrence-free survival was estimated by the method of Kaplan-Meier. Results: The mean postoperative follow-up time was 66.9 months (range, 24-149 months). Four patients developed local recurrence (4/50, 8.0%)including 3 cases of curettage group (3/20, 15.0%)and 1 case of resection group (1/30, 3.3%), there was no significant difference between curettage and resection group (P=0.289). The comparison of local recurrence between this curettage group (3/20, 15.0%) and the GCT group without fracture published before(10/116, 8.6%) in our institution also had no significant difference (P=0.407). There was no significant difference among the three types of fracture regarding the rate of local recurrence (P=0.160), but there was significant difference in the choice of surgical procedures for different fracture types (P=0.006). The complications: 2 patients (2/20, 10.0%)had joint degeneration in curettage group. 15 cases (15/30, 50.0%) had complications in resection group, 1 case of unicompartmental arthroplasty allograft absorption, 2 cases of infection and 12 cases of aseptic loosening after prosthesis replacement (including 1 case with periprosthetic fracture and 1 case with prosthesis fracture). The postoperative complications in curettage group had a significant reduction (P=0.005) when compared with the resection group. The mean score of functional evaluation with Musculoskeletal Tumor Society (MSTS) for curettage and resection group were (93.5±6.5)% and (82.6±12.9)% (F=4.838, P=0.033). Conclusions: (1) Extensive curettage did not increase the risk of local recurrence of giant cell tumor with pathological fracture around the knee. (2)The different fracture type had no effect on the local recurrence rate, but affect the decision of surgical procedures options. (3)The reconstructive complications in resection group was significant higher than curettage group, and the postoperative function of curettage group was better than resection group.
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Neoplasias Ósseas , Fraturas Espontâneas , Tumor de Células Gigantes do Osso , Articulação do Joelho , Adolescente , Adulto , Idoso , Neoplasias Ósseas/complicações , Feminino , Seguimentos , Humanos , Articulação do Joelho/patologia , Articulação do Joelho/cirurgia , Masculino , Pessoa de Meia-Idade , Recidiva Local de Neoplasia , Estudos Retrospectivos , Resultado do Tratamento , Adulto JovemRESUMO
Liver failure has various clinical types, a complex pathogenesis, and rapid disease progression, as well as a high mortality rate. Liver failure caused by hepatitis B virus infection is the most common type in China with severe conditions, various complications, and a mortality rate as high as 40%-90%. Invasive fungal disease secondary to acute-on-chronic liver failure can affect patients' prognosis and increase mortality rate. This article introduces the research advances in hepatitis B-related liver failure, artificial liver, and invasive fungal disease secondary to acute-on-chronic liver failure in 2016.
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Insuficiência Hepática Crônica Agudizada/diagnóstico , Insuficiência Hepática Crônica Agudizada/terapia , Pesquisa Biomédica/tendências , Hepatite B Crônica/diagnóstico , Hepatite B Crônica/terapia , Micoses/complicações , China , Vírus da Hepatite B , Humanos , Fígado Artificial , PrognósticoRESUMO
We suggest a spin-dependent hopping mechanism which includes the effect of the external magnetic field as well as hyperfine interaction (HFI) to explain the observed giant magnetoconductance (MC) in non-magnetic organic devices. Based on the extended Marcus theory, we calculate the MC by using the master equation. It is found that a MC value as large as 91% is obtained under a low driving voltage. For suitable parameters, the theoretical results are in good agreement with the experimental data. Influences of the carrier density, HFI, and the carrier localization on the MC value are investigated. Especially, it is found that a low-dimensional structure of the organic materials is favorable to get a large MC value.
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OBJECTIVE: The aim of this study was to elucidate the potential influence of MIR497HG on regulating proliferative capacity of human retinal endothelial cells (HRECs). MATERIALS AND METHODS: Relative expression levels of MIR497HG, microRNA-128-3p (miRNA-128-3p) and SIRT1 in HRECs treated with different doses of glucose and mannitol were detected by quantitative Real Time-Polymerase Chain Reaction (qRT-PCR). Dual-Luciferase reporter gene assay was conducted to assess the interaction among MIR497HG, miRNA-128-3p, and SIRT1. In addition, the potential effects of MIR497HG/miRNA-128-3p/SIRT1 axis on proliferative and migratory capacities in HRECs were evaluated by Cell Counting Kit-8 (CCK-8), 5-Ethynyl-2'- deoxyuridine (EdU) and transwell assay, respectively. RESULTS: High-level glucose (HG) treatment significantly downregulated MIR497HG and SIRT1 expression, whereas upregulated miRNA-128-3p expression in HRECs (p<0.05). MiRNA-128-3p was the target gene binding MIR497HG, and SIRT1 was the downstream gene of miRNA-128-3p. Overexpression of MIR497HG significantly attenuated proliferative and migratory abilities of HG-induced HRECs (p<0.05). Furthermore, decreased trends were partially reversed by overexpression of miRNA-128-3p or knockdown of SIRT1. CONCLUSIONS: MIR497HG is downregulated after HG treatment. In addition, it suppresses the proliferation and migration of HRECs by targeting miRNA-128-3p/SIRT1 axis, thus influencing the progression of diabetic retinopathy.
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Glucose/farmacologia , MicroRNAs/metabolismo , RNA Longo não Codificante/antagonistas & inibidores , Sirtuína 1/antagonistas & inibidores , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Células Cultivadas , Relação Dose-Resposta a Droga , Humanos , MicroRNAs/genética , RNA Longo não Codificante/genética , RNA Longo não Codificante/metabolismo , Sirtuína 1/genética , Sirtuína 1/metabolismoRESUMO
Flow-field-fractionation is a new separation technique that seems likely to have broad applicability. Its theoretical scope includes any solute for which one can find a solvent and a semipermeable membrane. The principles on which the technique is based are presented. Some experiments with polystyrene beads, viruses, and proteins verify that retention depends solely on diffusion coefficients.
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Fracionamento Químico/métodos , Técnicas de Química Analítica/métodos , Poliestirenos/isolamento & purificação , Proteínas/isolamento & purificação , Vírus/isolamento & purificação , DifusãoRESUMO
We report on the ferromagnetic characteristics of Zn(1-x)Mn(x)O nanorods synthesized by a seed-mediated solution method. The as-doped ZnO nanorods had a length about 200 nm and a diameter ranging from 20 to 30 nm. Magnetic property measurements revealed that the Zn(1-x)Mn(x)O nanorods exhibited weak ferromagnetism at 305 K. Similar solution method were also employed to fabricate the (Mn, Cu) co-doped nanostructures. The presence of Cu2+ was found to change the nanorod morphology (in the case of pure ZnO) to nanoparticle. On the other hand, not only the hysteresis curve saturated at lower magnetic field, but also the saturation magnetization was increased with the Cu doping. Transmission electron microscopy, X-ray photoelectron spectroscopy and Photoluminescence analysis suggested that the room temperature (RT) ferromagnetism could be originated from the Mn2+ doped into the ZnO lattice, and additional carriers due to the Cu co-doping may enhance the room temperature ferromagnetism in the Mn:ZnO system.
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We reported a case of carotid body tumor (Shamblin classification, typeâ ¢) patient on whom the tumor was tightly adhered to the carotid bifurcation and the carotid artery broke during the surgery,then autologous external jugular vein was employed to reconstruct the segmental defect of common-internal carotid artery after the tumor and involved common-internal carotid artery was resected. The patient felt no complaint during the two-year follow-up. Duplex scan demonstrated the patency of transplanted external jugular vein was a good graft without formation of aneurysm. At the time of 2 years after surgery, the transplanted vein arterialized without obvious stricture. This case implies that the external jugular vein grafting is a candidate for reconstruction of segmental carotid artery.
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Autoenxertos , Artéria Carótida Primitiva/cirurgia , Artéria Carótida Interna/cirurgia , Veias Jugulares/transplante , Artéria Carótida Externa , Tumor do Corpo Carotídeo/cirurgia , HumanosRESUMO
Two studies were performed to assess the efficacy of Lactobacillus plantarum B1 in prevention of pathogenic Escherichia coli K88 gastrointestinal infection in broilers. In an in vitro study, L. plantarum B1 showed resistance to acid and bile and inhibited the growth of E. coli K88. Additionally, L. plantarum B1 exhibited high ability to adhere to broiler embryo ileal epithelium. In an animal trial, 240 broilers at 1 d of age were randomly assigned to one of 4 treatment arms: negative control (NC) broilers fed a basal diet and not challenged; positive control (PC) broilers fed a basal diet and challenged with E. coli K88; L. plantarum (LP) treatment broilers fed a basal diet containing 2 × 109 cfu/kg L. plantarum B1 and challenged with E. coli K88; and antibiotic treatment (Anti) broilers fed a basal diet supplemented with colistin sulfate (20 mg/kg) and challenged with E. coli K88. Broilers fed L. plantarum B1 had greater (P ≤ 0.05) BW than those in the PC treatment on d 14 and 28. Dietary L. plantarum B1 decreased (P < 0.05) E. coli counts in the cecal contents on d 10 and 14, and increased (P < 0.05) cecal lactic acid bacteria (LAB) on d 8, 10, 14, and 28 compared with the PC treatment. Dietary supplementation of L. plantarum B1 increased (P < 0.05) the ileal mucosal secretory IgA concentration and reduced (P < 0.05) IL-2, IL-4, IFN-γ, and tumor necrosis factor-α levels in the ileum. Overall, these results suggest dietary supplementation of L. plantarum B1 promotes growth performance, lowers cecal E. coli counts, and increases the population of cecal LAB, as well as improves intestinal mucosal immunity in E. coli K88-challenged broilers.
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Galinhas , Infecções por Escherichia coli/veterinária , Lactobacillus plantarum/química , Lactobacillus plantarum/fisiologia , Doenças das Aves Domésticas/prevenção & controle , Probióticos/farmacologia , Ração Animal/análise , Animais , Aderência Bacteriana , Ceco/microbiologia , Galinhas/anatomia & histologia , Galinhas/crescimento & desenvolvimento , Galinhas/imunologia , Galinhas/microbiologia , Dieta/veterinária , Escherichia coli/fisiologia , Infecções por Escherichia coli/microbiologia , Infecções por Escherichia coli/prevenção & controle , Microbioma Gastrointestinal , Imunidade Inata , Intestinos/anatomia & histologia , Doenças das Aves Domésticas/microbiologia , Distribuição AleatóriaRESUMO
OBJECTIVE: To study the role of total flavonoids of hippophae rhamnoides in improving contractile [correction of contactile] function of stretched cardiac myocyte. METHOD: Flavonoids were given to stretched myocytes which were proved their contractile function decline and then myocyte contractile mechanics characteristics and calcium transfer were measured. RESULT: Flavonoids increased myocyte contractility, as indicated by myocyte shortening, velocity of shortening, peak +dL/dt and peak -dL/dt during shortening, in a concentration-dependent manner (r>0.9, P<0.001), and with no relation to the intracellular calcium transfer in the myocytes. CONCLUSION: Flavonoids of the traditional Chinese drug hippophae rhamnoides is effective in improving the contractile function of stretched cardiac myocyte in low dosage.
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Cálcio/metabolismo , Medicamentos de Ervas Chinesas/farmacologia , Flavonoides/farmacologia , Contração Miocárdica/efeitos dos fármacos , Miócitos Cardíacos/efeitos dos fármacos , Quercetina/farmacologia , Animais , Células Cultivadas , Relação Dose-Resposta a Droga , Medicamentos de Ervas Chinesas/uso terapêutico , Flavonoides/uso terapêutico , Insuficiência Cardíaca/tratamento farmacológico , Hippophae , Medicina Tradicional Chinesa , Miócitos Cardíacos/metabolismo , Quercetina/uso terapêutico , Ratos , Ratos Sprague-DawleyAssuntos
Cistite/tratamento farmacológico , Choque Séptico/tratamento farmacológico , Doenças da Bexiga Urinária/diagnóstico , Bexiga Urinária/patologia , Antibacterianos/uso terapêutico , Cistite/diagnóstico , Cistite/patologia , Feminino , Humanos , Pessoa de Meia-Idade , Ácido Penicilânico/análogos & derivados , Ácido Penicilânico/uso terapêutico , Piperacilina/uso terapêutico , Tazobactam , Tomografia Computadorizada por Raios X , Bexiga Urinária/microbiologia , Doenças da Bexiga Urinária/microbiologia , Doenças da Bexiga Urinária/patologiaRESUMO
The female sexual behavior including proceptivity, receptivity and sociosexual behavior of preferential approach to males was tested in 12 young adult female rats aged from 6 to 7 months and in 59 old female rats aged from 18 to 21 months with the exit method and the traditional non-exit method. The percentage of rats displaying a high lordosis quotient (LQ) and that of rats showing solicitation were lower in old females than in young females tested either with the non-exit method or the exit method. Only with the non-exit method were the mount frequency per minute of male rats toward old females of the high-LQ group and the solicitation score of old female rats lower as compared to young females. The incidence of preferential approach of the female rats, whether young or old, toward intact young males and their time spent in the compartment of intact young males were not different, however, the frequency of old female rats to visit the arena of intact young males was lower than that of young females. In summary, the major age-related changes in female sexual behavior, the low percentage of rats displaying high LQ and of rats showing solicitation, are quite robust and environmentally independent.
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Envelhecimento/fisiologia , Comportamento Sexual Animal/fisiologia , Fatores Etários , Animais , Copulação/fisiologia , Feminino , Ratos , Ratos Endogâmicos , Fatores SexuaisRESUMO
The nature and theory of flow field-flow fractionation is described, and its potential applicability to virus-like particles is discussed. Different virus types are shown to be retained at different levels. Retention can be controlled by variation of the experimental parameters, in good agreement with theory. However, a mild adsorption effect is indicated and requires the development of alternate strategies for measuring diffusion coefficients. For Qbeta, our value agrees well within 10% of literature values; the values obtained for other viruses, using Abeta as an internal standard, are untested. Finally, it is demonstrated that flow field-flow fractionation can cleanly fractionate two viruses from one another and from an albumin impurity, that samples as large as several milligrams in size can be analyzed, and that the method has potential utility in the quantitative and qualitative analysis of virus systems.
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Fracionamento Químico/métodos , Técnicas de Química Analítica/métodos , Colífagos/isolamento & purificação , Albuminas/isolamento & purificação , Ferritinas/isolamento & purificação , Modelos BiológicosRESUMO
The scavenging effects of tetramethylpyrazine (ligustrazine, Lig) isolated from Ligusticum wallichii Franch on active oxygen free radicals were studied using spin trapping technic and chemiluminescence methods. The scavenging rate of superoxide anion (O2-.) by Lig (25 mg.ml-1) was 100% in xanthine/xanthine oxidase (Xan/XO) system, and that of hydroxyl radical (OH-.) was 44% in Fenton's reaction. The scavenging rate of lipid peroxyl radical (LOO-.) by Lig (25 mg.ml-1) was 80% in peroxidizing microsome system. It is possible that Lig scavenged O2-. by catalyzing its spontaneous dismutation. The results showed that Lig had strong effects of scavenging cyotoxic oxygen free radicals (O2-., LOO-., OH-.).