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71.
Rearrangements involving chromosomes 2 and 22 were described not only as acquired abnormalities in a variety of human neoplasias but also in the constitutional karyotype suggesting the existence of a greater fragility in some specific regions in these chromosomes. Patients with DiGeorge and Velocardiofacial syndromes have a deletion on 22q11 leading to haploinsufficiency for one or more gene(s). We report a patient with velocardiofacial syndrome in which cytogenetic and fluorescence in situ hybridization analysis showed a rare t(2;22) and deletion in the 22q11 region.  相似文献   
72.
Intravenous (i.v.) injections of yohimbine, phentolamine, prazosine and phenoxybenzamine lowered blood pressure and increased heart rate in conscious rats. Intracerebroventricular (i.c.v.) injections of yohimbine and phentolamine increased blood pressure and heart rate; this was antogonized by pretreatment with clonidine. Phenoxybenzamine and prozosine had no effect or gave hypotension and tachycardia on i.c.v. injection. Pentobarbitone anaesthesia partly antagonized the cardiovascular effects of all alpha-adrenoceptor antagonist. Synthesis and utilization of central noradrenaline was increased by i.v. or i.c.v. yohimbine; anaesthesia partly antagonized this effect. In peripheral tissues others have found that yohimbine, tolazoline, piperoxan and phentolamine are potent blockers of the presynaptic alpha-adrenoceptors while phenoxybenzamine and prazosine act preferentially on postsynaptic alpha-adrenoceptors. The differentiated cardiovascular response to i.c.v. injection of these blockers may reflect their different affinity to central pre- and postsynaptic alpha-adrenoceptors.  相似文献   
73.
BackgroundAdequate treatment of arterial hypertension and achieving arterial hypertension goals in are important in reducing cardiovascular outcomes.ObjectivesTo describe angiotensin receptor blockers in monotherapy or double combination therapy and the rate of arterial hypertension control.MethodsThis cross-sectional study evaluated patients who were using angiotensin receptor blockers between 2017 and 2020. Those using three or more antihypertensive drugs were excluded. The analyzed variables included sex, age, body mass index, valid home blood pressure monitoring (HBPM) measurements, casual and HBPM systolic and diastolic blood pressure measurements, blood pressure variability, and antihypertensive and angiotensin receptor blocker class. Paired t, chi-square, and Fisher’s exact tests were used, as well as overlapping 95% confidence intervals and a significance level of 5% (p < 0.05).ResultsOf 17,013 patients, 12,813 met the inclusion criteria, 62.1% of whom were female. The mean number of valid measurements was 23.3 (SD, 2.0). The mean HBPM and casual measurements for systolic blood pressure were 126.8 (SD, 15.8) mmHg and 133.5 (SD, 20.1) mmHg (p <0.001), respectively, while those for diastolic blood pressure were 79.1 (SD, 9.7 mmHg) and 83.6 (SD, 11.9) mmHg (p <0.001), respectively. Losartan was the most common angiotensin receptor blocker and resulted in the highest blood pressure values. Combinations of angiotensin receptor blockers with diuretics or calcium channel antagonists resulted in lower blood pressure values.ConclusionsMore than half of the patients used losartan, although it was the least efficient drug for reducing and controlling blood pressure.  相似文献   
74.
Nanotechnology experienced a great technological advance after the discovery of the graphene family (graphene – Gr, graphene oxide – GO, and reduced graphene oxide-rGO). Based on the excellent properties of these materials, it is possible to develop novel polymeric nanocomposites for several applications in our daily routine. One of the most prominent applications is for food packaging, offering nanocomposites with improved thermal, mechanical, anti-microbial, and barrier properties against gas and water vapor. This paper reviewed food packaging from its inception to the present day, with the development of more resistant and intelligent packaging. Herein, the most common combinations of polymeric matrices (derived from non-renewable and renewable sources) with Gr, GO, and rGO and their typical preparation methods are presented. Besides, the interactions present in these nanocomposites will be discussed in detail, and their final properties will be thoroughly analyzed as a function of the preparation technique and graphene family-matrix combinations.

Food packaging based on nanotechnology of polymeric nanocomposites of graphene and graphene oxide results in packaging with better thermal, mechanical, antimicrobial, electrical packaging, moisture barrier and gas properties.  相似文献   
75.
Aim: This systematic review examined the additional effect of taking omega-3 supplements on periodontal therapy. Methods: The focused question was “What is the possible effect of omega-3 supplementation concomitant to non-surgical periodontal therapy on clinical periodontal parameters?” Databases Cochrane, Embase, Google Scholar, PubMed, and Web of Science (January-July 2021) were searched to identify appropriate studies. Randomized clinical trials (RCT) about non-surgical therapy with omega-3 supplementation, with at least 3 months of supplementation period were included. Cochrane risk of bias tool version 2 and Grading of Recommendations Assessment, Development, and Evaluation were used. Results: A total of 1556 studies were found, of which eight studies met the inclusion criteria. All eight studies evaluated periodontal probing depth and clinical attachment loss; plaque and gingival inflammation were evaluated in seven studies. High variety of omega-3 dosage, different study lengths, questionable results from periodontal therapy (including test and control groups), high risk of bias and moderate quality of evidence prevented a satisfactory conclusion regarding the benefits of omega-3 supplementation. The studies’ high heterogeneity avoided meta-analysis. Conclusion: Notwithstanding all limitations, the promising effects of omega-3 supplementation presented in two six-month studies encourage performing RCT with better-defined treatment protocols and greater methodological rigor.  相似文献   
76.
77.
Hemorrhagic tumor necrosis is an inflammatory event that leads to selective destruction of malignant tissues, with both potentially toxic and beneficial consequences. A pilot clinical trial was undertaken combining tumor necrosis factor-alpha (TNF-alpha) with the monoclonal antibody R24 (MoAb R24) against GD3 ganglioside in patients with metastatic melanoma. Patients received MoAb R24 to recruit leukocytes to the tumor followed by low doses of recombinant TNF-alpha to activate leukocytes. Eight patients were treated and seven patients had mild toxicity. One patient with extensive metastatic melanoma developed tumor lysis syndrome within hours after treatment with almost complete necrosis of bulky tumors in multiple visceral sites. To our knowledge, this is the first documented case of hemorrhagic tumor necrosis in a patient with metastatic cancer in multiple visceral sites.  相似文献   
78.
Hay  CR; Laurian  Y; Verroust  F; Preston  FE; Kernoff  PB 《Blood》1990,76(5):882-886
Home therapy with porcine factor VIIIC was safe and effective when administered to five hemophilic patients over periods of 8 1/2, 6, 4, 3 1/2, and 2 years. No significant transfusion reactions occurred. Before treatment with porcine factor VIIIC, all five had high-level, high- responding anti-human VIIIC inhibitors initially lacking anti-porcine factor VIIIC activity. Although specific anti-porcine VIIIC inhibitors arose in all patients, these were generally transient, and only one patient became refractory to treatment. We believe that porcine factor VIIIC is the treatment of choice in patients whose inhibitors do not cross-react. All five patients lost their original anti-human VIIIC inhibitors after starting treatment with porcine VIIIC, permitting the reintroduction of human VIIIC in three of them. There has been no recurrence of anti-human VIIIC inhibitor activity during 2 to 3 years of regular treatment with human VIIIC in these patients. This suggests that tolerance to human VIIIC has arisen as a result of treatment with porcine VIIIC. Porcine VIIIC may have a role in the desensitization of some factor VIIIC inhibitor patients.  相似文献   
79.
In this study we assessed neonatal complications of diabetic in 50 pregnant women at a University Hospital during 2001-2002: 13 (26%) with type 1 diabetes (DM1), 16 with DM2, and 21 (42%) with gestational DM (GDM). The mean outpatient follow-up was at 16.3+/-8 wk for patients with DM1, 22.9+/-7.5 wk for DM2, and 26.0+/-8.9 wk for GDM. Mean HbA1c, fasting and 2-h post-prandial glycemia on first attendance were respectively: 6.1+/-1,1% (RV: 2.6-6.2%), 132+/-39 mg/dL and 190+/-54 mg/dL. 22 patients were on insulin and 15 were on oral antidiabetic agents (OA) at first evaluation. OA were taken on conception and during the first pregnancy trimester and no malformations were seen in the children. Their metabolic profile was similar to other pregnant women. Caesarean section was needed in 54.5% of deliveries. Complications: 56.1% were macrosomic babies, with a mean fetal weight of 3.48+/-0.73 Kg, with no differences according to treatment (insulin vs. OA). We conclude that diabetic pregnant women begin their prenatal care at a later period, often taking OA that are not officially advised to be used during pregnancy and are not in a regular metabolic control. As a result, they have macrosomic infants. Even though we have found no complications related to the OA use during pregnancy, we should not encourage their use until more safety studies are available.  相似文献   
80.
The antibody response against Leishmania (Leishmania) amazonensis crude antigen was measured through the indirect immunofluorescent assay (IFA) and the immunoenzymatic assay (ELISA) in 114 patients with cutaneous leishmaniasis (CL) in Brazil. Fifty-four patients were infected by Leishmania (Viannia) braziliensis, and 60 patients had L. (V.) guyanensis infection. Patients were comparable by age, sex, disease duration and the Montenegro skin test diameter. L. (V.) braziliensis-infected patients showed significant lower number of ulcerated lesions, greater ulcerated area and higher proportion of lymph node enlargement. Sensitivity of IFA was 79.6% (95% CI 66.1-88.9) and 71.7% (95% CI 58.4-82.2) for L. (V.) braziliensis and L. (V.) guyanensis-infected patients, respectively (P=0.324). Sensitivity of ELISA was 98.2% (95% CI 88.8-99.9) and 85.0% (95% CI 72.9-92.5) for L. (V.) braziliensis and L. (V.) guyanensis-infected patients, respectively (P=0.018). Significant differences were observed in the magnitude of the antibody response before treatment with higher levels detected in L. (V.) braziliensis-infected patients by both serologic techniques. Eighty-four patients had serologic evaluations before and 12 weeks after treatment with meglumine antimoniate, 20 mg/kg/day for 20 days. Significant lower optic density values were observed after treatment with both species independent of cure or failure. Our data showed that L. (V.) braziliensis induces a higher antibody response against L. (L.) amazonensis antigens than L. (V.) guyanensis and that down-modulation of the antibody response occurs shortly during disease evolution after treatment. Moreover the data support the use of ELISA as a better tool for detection of antibodies in CL.  相似文献   
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