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101.
Over the last decade, use of the term bronchioloalveolar carcinoma (BAC) has come under constant scrutiny as some consider it an anachronism or a term that provides incorrect information about this neoplasm. To that extent, it has recently been suggested to replace the term BAC with that of in situ adenocarcinoma (AIS) or minimally invasive adenocarcinoma (MIA) for small solitary adenocarcinomas with either pure bronchioloalveolar growth (AIS) or predominant bronchioloalveolar growth and ≤5-mm invasion (MIA). However, as of today, there is no comprehensive study of these tumors, and most of what has been published in this context is based on a review of the literature that focused on scattered short series of cases describing either small adenocarcinomas or BAC. More recently, a large series of cases of a more comprehensive nature that included all early-stage adenocarcinomas (T1N0M0) has cast some doubt regarding the need for the proposed change in nomenclature. At the same time, it was suggested that if indeed that notion is maintained, a more serious and comprehensive study of actual cases must be undertaken. The details of the issues surrounding this subject are presented in this review. 相似文献
102.
103.
Resistance Exercise Restores Endothelial Function and Reduces Blood
Pressure in Type 1 Diabetic Rats
Marcelo Mendon?a Mota Tharciano Luiz Teixeira Braga da Silva Milene Tavares Fontes André Sales Barreto Jo?o Eliakim dos Santos Araújo Ant?nio Cesar Cabral de Oliveira Rogério Brand?o Wichi Márcio Roberto Viana Santos 《Arquivos brasileiros de cardiologia》2014,103(1):25-32
Background
Resistance exercise effects on cardiovascular parameters are not consistent.Objectives
The effects of resistance exercise on changes in blood glucose, blood pressure and vascular reactivity were evaluated in diabetic rats.Methods
Wistar rats were divided into three groups: control group (n = 8); sedentary diabetic (n = 8); and trained diabetic (n = 8). Resistance exercise was carried out in a squat device for rats and consisted of three sets of ten repetitions with an intensity of 50%, three times per week, for eight weeks. Changes in vascular reactivity were evaluated in superior mesenteric artery rings.Results
A significant reduction in the maximum response of acetylcholine-induced relaxation was observed in the sedentary diabetic group (78.1 ± 2%) and an increase in the trained diabetic group (95 ± 3%) without changing potency. In the presence of NG-nitro-L-arginine methyl ester, the acetylcholine-induced relaxation was significantly reduced in the control and trained diabetic groups, but not in the sedentary diabetic group. Furthermore, a significant increase (p < 0.05) in mean arterial blood pressure was observed in the sedentary diabetic group (104.9 ± 5 to 126.7 ± 5 mmHg) as compared to that in the control group. However, the trained diabetic group showed a significant decrease (p < 0.05) in the mean arterial blood pressure levels (126.7 ± 5 to 105.1 ± 4 mmHg) as compared to the sedentary diabetic group.Conclusions
Resistance exercise could restore endothelial function and prevent an increase in arterial blood pressure in type 1 diabetic rats. 相似文献104.
Kosek M Yori PP Gilman RH Calderon M Zimic M Chuquiyauri R Jeri C Pinedo-Cancino V Matthias MA Llanos-Cuentas A Vinetz JM 《The American journal of tropical medicine and hygiene》2012,86(4):580-586
Molecular tools to distinguish strains of Plasmodium vivax are important for studying the epidemiology of malaria transmission. Two sets of markers-tandem repeat (TR) polymorphisms and MSP3α-were used to study Plasmodium vivax in patients in the Peruvian Amazon region of Iquitos. Of 110 patients, 90 distinct haplotypes were distinguished using 9 TR markers. An MSP3α polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) using HhaI and AluI revealed 8 and 9 profiles, respectively, and 36 profiles when analyzed in combination. Combining TR and PCR-RFLP markers, 101 distinct molecular profiles were distinguished among these 110 patients. Nine TR markers arrayed along a 100 kB stretch of a P. vivax chromosome containing the gene for circumsporozoite protein showed non-linear linkage disequilibrium (I(SA) = 0.03, P = 0.001). These findings demonstrate the potential use of TR markers for molecular epidemiology studies. 相似文献
105.
LA Marcos N Arrospide S Recuenco C Cabezas GJ Weil PU Fischer 《The American journal of tropical medicine and hygiene》2012,87(3):491-494
Abstract. DNA sequence comparisons are useful for characterizing proposed new parasite species or strains. Microfilariae with an atypical arrangement of nuclei behind the cephalic space have been recently described in human blood samples from the Amazon region of Peru. Three blood specimens containing atypical microfilariae were genetically characterized using three DNA markers (5S ribosomal DNA, 12S ribosomal DNA, and cytochrome oxidase I). All atypical microfilariae were clustered into the Mansonella group and indistinguishable from M. ozzardi based on these DNA markers. 相似文献
106.
Lu J Sun Y Nombela-Arrieta C Du KP Park SY Chai L Walkley C Luo HR Silberstein LE 《Experimental hematology》2012,40(4):307-17.e3
Hematopoietic stem cells (HSCs) reside in complex bone marrow microenvironments, where niche-induced signals regulate hematopoiesis. Focal adhesion kinase (Fak) is a nonreceptor protein tyrosine kinase that plays an essential role in many cell types, where its activation controls adhesion, motility, and survival. Fak expression is relatively increased in HSCs compared to progenitors and mature blood cells. Therefore, we explored its role in HSC homeostasis. We have used the Mx1-Cre-inducible conditional knockout mouse model to investigate the effects of Fak deletion in bone marrow compartments. The total number as well as the fraction of cycling Lin(-)Sca-1(+)c-kit(+) (LSK) cells is increased in Fak(-/-) mice compared to controls, while hematopoietic progenitors and mature blood cells are unaffected. Bone marrow cells from Fak(-/-) mice exhibit enhanced, long-term (i.e., 20-week duration) engraftment in competitive transplantation assays. Intrinsic Fak function was assessed in serial transplantation assays, which showed that HSCs (Lin(-)Sca-1(+)c-kit(+)CD34(-)Flk-2(-) cells) sorted from Fak(-/-) mice have similar self-renewal and engraftment ability on a per-cell basis as wild-type HSCs. When Fak deletion is induced after engraftment of Fak(fl/fl)Mx1-Cre(+) bone marrow cells into wild-type recipient mice, the number of LSKs is unchanged. In conclusion, Fak inactivation does not intrinsically regulate HSC behavior and is not essential for steady-state hematopoiesis. However, widespread Fak inactivation in the hematopoietic system induces an increased and activated HSC pool size, potentially as a result of altered reciprocal interactions between HSCs and their microenvironment. 相似文献
107.
Aging represents a major risk factor for prostate cancer; however, mechanisms responsible for this relationship remain unclear. Preclinical and some clinical investigations support the protective role of selenium against prostate cancer possibly through the reduction of oxidative stress. While increased levels of oxidative stress together with decreases in selenium and the major cellular antioxidant glutathione (GSH) are common in tissues of old animals, there is little data available on these parameters in the prostate. In the present study we have compared the levels of selenium, GSH and protein-bound GSH (GSSP) in blood and prostate tissues in young (4-month), mature (12-month), old (18 month), and very old (24 month) male F344 rats. Each prostate lobe (dorsolateral, DL; anterior, AL; ventral, VL) was analyzed separately based upon their differing potential for prostate cancer development. At all ages, selenium levels were lowest in DL相似文献
108.
Salvador Cervera-enguix Cesar A. Soutullo Ignacio Landecho Ricardo Murillo-jelsbak 《International journal of psychiatry in clinical practice》2013,17(3):193-197
BACKGROUND Quality of Life (QoL) assessments are common in medicine and, recently, in psychiatry, mostly in patients with chronic mental illness. We evaluated QoL in depressed outpatients treated with venlafaxine-XR over a period of 24 weeks. METHOD We evaluated 833 patients with DSM-IV major depression using the Hamilton Depression Rating Scale (HAM-D), the Hamilton Anxiety Rating Scale (HAM-A), the Montgomery-Åsberg Depression Rating Scale (MÅDRS), and the QoL in Depression Scale (QLDS). The patients received venlafaxine-XR and we evaluated them after 4, 8, and 24 weeks of treatment. RESULTS HAM-D scores decreased from a baseline of 24.6 - 6.3 to 6.0 - 5.5 (mean - SD; P <0.0001) after 24 weeks. HAM-A scores decreased from a baseline of 32.3 - 7.9 to 6.8 - 6.8 ( P <0.0001) after 24 weeks. QLDS scores decreased from a baseline of 25.8 - 5.8 to 6.6 - 7.5 ( P <0.0001) after 24 weeks, indicating improvement in QoL. The response after 4 weeks was also significant and continued improving during the study. Venlafaxine-XR was shown to be safe and well tolerated. DISCUSSION Open-label venlafaxine-XR was safe, effective, well tolerated, and improved not only depression and anxiety symptoms, but also QoL, in outpatients with major depression. This study has the limitations of any non-randomized, non-blinded multiple-site clinical trial. 相似文献
109.
Ana Carolina Fragoso Motta Cristiane Aparecida Nogueira Bataglion Maria Cristina Foss-Freitas Milton Cesar Foss Marilena Chinali Komesu 《Clinics (S?o Paulo, Brazil)》2013,68(3):427-430
OBJECTIVE:
To evaluate the effects of the levels of glycemic control on the frequency of clinical complications following invasive dental treatments in type 2 diabetic patients and suggest appropriate levels of fasting blood glucose and glycated hemoglobin considered to be safe to avoid these complications.METHOD:
Type 2 diabetic patients and non-diabetic patients were selected and divided into three groups. Group I consisted of 13 type 2 diabetic patients with adequate glycemic control (fasting blood glucose levels <140 mg/dl and glycated hemoglobin (HbA1c) levels <7%). Group II consisted of 15 type 2 diabetic patients with inadequate glycemic control (fasting blood glucose levels >140 mg/dl and HbA1c levels >7%). Group III consisted of 18 non-diabetic patients (no symptoms and fasting blood glucose levels <100 mg/dl). The levels of fasting blood glucose, glycated HbA1c, and fingerstick capillary glycemia were evaluated in diabetic patients prior to performing dental procedures. Seven days after the dental procedure, the frequency of clinical complications (surgery site infections and systemic infections) was examined and compared between the three study groups. In addition, correlations between the occurrence of these outcomes and the glycemic control of diabetes mellitus were evaluated.RESULTS:
The frequency of clinical outcomes was low (4/43; 8.6%), and no significant differences between the outcome frequencies of the various study groups were observed (p>0.05). However, a significant association was observed between clinical complications and dental extractions (p = 0.02).CONCLUSIONS:
Because of the low frequency of clinical outcomes, it was not possible to determine whether fasting blood glucose or glycated HbA1c levels are important for these clinical outcomes. 相似文献110.