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排序方式: 共有1668条查询结果,搜索用时 140 毫秒
1.
Improvement in Tricuspid Annular Plane Systolic Excursion with Pulmonary Hypertension Therapy in Pediatric Patients 下载免费PDF全文
2.
Case report Leptomeningeal involvement in diffuse intrinsic brain stem gliomas is rarely diagnosed clinically and in majority of the instances diagnosed only on postmortem examination. We report two cases of diffuse pontine glioma diagnosed clinicoradiologically and treated with conventional radiotherapy.Observations On follow-up, both patients showed clinical features suggestive of meningeal spread although imaging for pontine tumor showed stable disease. Leptomeningeal disease in the spine was confirmed on imaging and in one case by cerebrospinal fluid examination also. During the follow-up of patients with pontine glioma, the possibility of leptomeningeal involvement must be borne in mind. 相似文献
3.
Practicing Behavioral Sex Therapy in India: Selection, Modifications, Outcome, and Dropout 总被引:1,自引:0,他引:1
A file review of 178 male patients with sexual dysfunction revealed that high income, married status, presence of partner at evaluation, and liberal attitude towards sexuality increased the chances of selection for behavioral sex therapy. The outcome of therapy was associated with treatment adherence. Participation of the conjoint unit resulted in lower dropout rates. 相似文献
4.
BACKGROUND: A common problem facing patients suffering from psoriasis is the need for surgery that requires incision through active psoriatic skin. Many patients have been denied surgery because of the fear of an increased risk of infection, decreased wound healing ability, and worsening of the psoriatic lesions. OBJECTIVE: To assess the practices and beliefs of dermatologists and surgeons (orthopedic and plastic surgeons) faced with the decision of whether to operate through active psoriatic skin. METHODS: Dermatologists, orthopedic surgeons, and plastic surgeons selected from various professional membership lists from five representative cities were sent a survey to ascertain their opinions on operating on active psoriatic skin. Psoriatic patients were also given forms asking about the severity of their psoriasis and whether they had ever been denied surgery. RESULTS: Dermatologists are more likely to condone surgery in active psoriatic skin and to believe that there is not a risk of increased infection or decreased wound healing than are orthopedic surgeons and plastic surgeons. These findings are statistically significant (P<0.05). CONCLUSION: With proper preoperative measures and dermatologic treatment, surgery can be performed on active psoriatic skin in most cases with minimal reservations, although a controlled, prospective study is necessary to arrive at a definitive conclusion. 相似文献
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This preliminary study was undertaken to observe tumour response and normal tissue tolerance to hyperfractionation. This study showed encouraging locoregional control rate in advanced head and neck cancer. Responses T4 tumors are poor and are prone to recur. This indicates that probably greater dose is needed to control T4 disease. We used 7920 cGy for T4 and late T3 status tumour. This dose is well tolerated by patients. Control of T4 tumours may further be increased by increasing total dose, but in view of inadequate clear cut numerical data of tissue tolerance derived by L-Q = Linear Quadratic formula which is still under clinical trial, further increase in total dose cannot be overemphasized. Longer follow up is necessary to assess the long term control rate and late tissue reaction. There is a need of randomized controlled clinical trial to compare hyperfractionation and conventional fractionation. In next phase we are undertaking randomized study of twice daily, daily and weekly fractionation in advanced head and neck cancer. 相似文献
7.
Boxall S Stanton T Hirai K Ward V Yasui T Tahara H Tamori A Nishiguchi S Shiomi S Ishiko O Inaba M Nishizawa Y Dawes R Bodmer W Beverley PC Tchilian EZ 《Human molecular genetics》2004,13(20):2377-2384
The CD45 antigen is a haemopoietic cell specific tyrosine phosphatase essential for antigen receptor mediated signalling in lymphocytes. Expression of different patterns of alternatively spliced CD45 isoforms is associated with distinct functions. We recently identified a polymorphism in exon 6 (A138G) of the gene encoding CD45 (PTPRC) that results in altered CD45 splicing. The 138G allele is present at a high frequency among Japanese (23.7%), with 5.1% individuals homozygous for the G allele. In this study we show that the A138G polymorphism is the cause of altered CD45 isoform expression, promoting splicing towards low molecular weight CD45 isoforms. We further report that the frequency of A138G heterozygotes is significantly reduced in number in cohorts of patients with autoimmune Graves' disease or hepatitis B infection, whereas G138G homozygotes are absent from a cohort of Hashimoto's thyroiditis patients. We also show that 138G individuals exhibit altered cytokine production in vitro and an increased proportion of memory T cells. These data suggest that the 138G variant allele strongly influences these diseases by modulation of immune mechanisms and may have achieved its high frequency as a result of a natural selection probably related to pathogen resistance. 相似文献
8.
Rana Al-Sadi Prashant Nighot Meghali Nighot Mohammad Haque Manmeet Rawat Thomas Y. Ma 《The American journal of pathology》2021,191(5):872-884
Defective intestinal tight junction (TJ) barrier is an important pathogenic factor of inflammatory bowel disease. To date, no effective therapies that specifically target the intestinal TJ barrier are available. The purpose of this study was to identify probiotic bacterial species or strains that induce a rapid and sustained enhancement of intestinal TJ barrier and protect against the development of intestinal inflammation by targeting the TJ barrier. After high-throughput screening of >20 Lactobacillus and other probiotic bacterial species or strains, a specific strain of Lactobacillus acidophilus, referred to as LA1, uniquely produced a marked enhancement of the intestinal TJ barrier. LA1 attached to the apical membrane surface of intestinal epithelial cells in a Toll-like receptor (TLR)-2–dependent manner and caused a rapid increase in enterocyte TLR-2 membrane expression and TLR-2/TLR-1 and TLR-2/TLR-6 hetero-complex–dependent enhancement in intestinal TJ barrier function. Oral administration of LA1 caused a rapid enhancement in mouse intestinal TJ barrier, protected against a dextran sodium sulfate (DSS) increase in intestinal permeability, and prevented the DSS-induced colitis in a TLR-2– and intestinal TJ barrier–dependent manner. In conclusion, we report for the first time that a specific strain of LA causes a strain-specific enhancement of intestinal TJ barrier through a novel mechanism that involves the TLR-2 receptor complex and protects against the DSS-induced colitis by targeting the intestinal TJ barrier.Intestinal epithelial tight junctions (TJs) are the apical-most junctional complexes and act as a functional and structural barrier against the paracellular permeation of harmful luminal antigens, which promote intestinal inflammation.1 The increased intestinal permeability caused by defective intestinal epithelial TJ barrier or a leaky gut is an important pathogenic factor that contributes to the development of intestinal inflammation in inflammatory bowel disease (IBD) and other inflammatory conditions of the gut, including necrotizing enterocolitis and celiac disease.2,3 Clinical studies in patients with IBD have found that a persistent increase in intestinal permeability after clinical remission is predictive of poor clinical outcome and early recurrence of the disease, whereas normalization of intestinal permeability correlates with a sustained long-term clinical remission.4, 5, 6 Accumulating evidence has found that a defective intestinal TJ barrier plays an important role in exacerbation and prolongation of intestinal inflammation in IBD. Currently, no effective therapies that specifically target the tightening of the intestinal TJ barrier are available.Intestinal microbiota play an important role in modulating the immune system and in the pathogenesis of intestinal inflammation.7 Patients with IBD have bacterial dysbiosis in the gut, characterized by a decrease in bacterial diversity and an aberrant increase in some commensal bacteria, which are an important factor in the pathogenesis of intestinal inflammation.8,9 Normal microbial flora of the gastrointestinal tract consists both of bacteria that are known to have beneficial effects (probiotic bacteria) on intestinal homeostasis and bacteria that could potentially have detrimental effects on gut health (pathogenic bacteria).10 The modulation of intestinal microflora affects the physiologic and pathologic states in humans and animals. For example, fecal transplantation from healthy, unaffected individuals to patients with refractory Clostridium difficile colitis is curative in up to 94% of the treated patients, and transfer of stool microbiome from obese mice induces obesity in previous lean mice, whereas transfer of microbiome from lean mice preserves the lean phenotype.11, 12, 13 The beneficial effects of gut microbiota are host and bacterial species-specific.14 Although multiple studies indicate that some commensal bacteria play a beneficial role in gut homeostasis by preserving or promoting the intestinal barrier function, because of conflicting reports, it remains unclear which probiotic species cause a persistent predictable enhancement in the TJ barrier and could be used to treat intestinal inflammation by targeting the TJ barrier. For example, some studies suggest that Lactobacillus acidophilus, Lactobacillus casei, Lactobacillus plantarum, or Lactobacillus rhamnosus cause a modest enhancement in the intestinal epithelial TJ barrier, whereas others have found minimal or no effect of these probiotic species on the intestinal TJ barrier.15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25 The major aim the current study was to perform a high-throughput screening of Lactobacillus and other bacterial species to identify probiotic species that induce a rapid, predictable, and marked increase in the intestinal epithelial TJ barrier and protect against the development of intestinal inflammation by preserving the intestinal TJ barrier.In the studies described herein, most of the probiotic species tested (>20 species or strains) had a modest or minimal effect on intestinal TJ barrier function. L. acidophilus uniquely caused a rapid and marked increase in intestinal TJ barrier function. Further analysis indicated that the effect of L. acidophilus was strain-specific, limited to a specific strain of L. acidophilus, and did not extend to other L. acidophilus strains. The L. acidophilus enhancement of the intestinal TJ barrier was mediated by live bacterial-enterocyte interaction that involved Toll-like receptor (TLR)-2 heterodimeric complexes on the apical membrane surface of intestinal epithelial cells. Our animal studies also found that L. acidophilus causes a marked enhancement in mouse intestinal barrier function and protects against the dextran sodium sulfate (DSS)–induced colitis by preserving and augmenting the mouse intestinal barrier function in a strain-specific manner. 相似文献
9.
The order of abundance of different mallophagan species on poultry birds in Dehradun (India) has been found to be Menopon gallinae greater than Menacanthus cornutus greater than Menacanthus stramineus greater than Goniocotes gallinae greater than Goniodes dissimilis greater than Lipeurus caponis greater than Lipeurus lawrensis tropicalis greater than Goniodes gigas. The intensity of these species upon 1249 birds has been recorded by coding system. The correlation between the monthly incidence of different species and environmental temperature as well as R.H. has been recorded. The degree of association between four most commonly occurring combinations has also been analysed. 相似文献
10.
Sharma R Yellowley CE Civelek M Ainslie K Hodgson L Tarbell JM Donahue HJ 《Annals of biomedical engineering》2002,30(3):371-378
Vascular smooth muscle cells (VSM) are normally exposed to transmural fluid flow shear stresses, and after vascular injury, blood flow shear stresses are imposed upon them. Since Ca2+ is a ubiquitous intracellular signaling molecule, we examined the effects of fluid flow on intracellular Ca2+ concentration in rat aortic smooth muscle cells to assess VSM responsiveness to shear stress. Cells loaded with fura 2 were exposed to steady flow shear stress levels of 0.5–10.0 dyn/cm2 in a parallel-plate flow chamber. The percentage of cells displaying a rise in cytosolic Ca2+ ion concentration ([Ca2+]i) increased in response to increasing flow, but there was no effect of flow on the ([Ca2+]i) amplitude of responding cells. Addition of Gd3+ (10 M) or thapsigargin (50 nM) significantly reduced the percentage of cells responding and the response amplitude, suggesting that influx of Ca2+ through ion channels and release from intracellular stores contribute to the rise in ([Ca2+]i) in response to flow. The addition of nifedipine (1 or 10 M) or ryanodine (10 M) also significantly reduced the response amplitude, further defining the role of ion channels and intracellular stores in the Ca2+ response. © 2002 Biomedical Engineering Society.
PAC2002: 8716Uv, 8719Uv, 8716Dg, 8719Ff 相似文献