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81.
Gauwerky  C; Golde  DW 《Blood》1980,56(5):886-891
We have investigated the hormonal responsiveness of K562 cells using a serum-substituted in vitro clonogenic assay. Dexamethasone inhibited colony formation by the K562 cells, and the inhibitory effect could be reversed by progesterone (10(-6) M). Fluoxymesterone caused a prominent enhancement of K562 colony growth, whereas estriol had no effect. Stimulation by triiodothyronine was maximal at 10(-7) M, and the thyroid effect could be abrogated by the beta 2-adrenergic antagonist butoxamine in equimolar concentrations. Using standard tissue culture conditions, the beta-adrenergic agent isoproterenol, but not the alpha catecholamine phenylephrine, enhanced the proliferation of K562 cells. When K562 cells were grown under hormone-depleted conditions, they developed responsiveness to phenylephrine and were no longer stimulated by isoproterenol. DbcAMP and prostaglandins of the E series also caused K562 colony enhancement. Prostaglandin F2 alpha had no effect on cell proliferation. Insulin was an effective stimulant of colony formation of K562 cells, as were human growth hormone and ovine prolacin. Bovine growth hormone had no effect. Our results are consistent with the identificaiton of K562 as an erythroid line, and they indicate that K562 cells respond to endocrine hormones in a manner analogous to normal erythroid progenitors.  相似文献   
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A 4-year-old boy had surgical debulking of a cerebral astrocytoma followed by chemotherapy. He developed a subdural empyema with a teicoplanin and methicillin resistant Staphylococcus aureus. He was successfully treated with surgical drainage and 6 weeks of antibiotic therapy which included linezolid, rifampicin and metronidazole. Linezolid may be successful in treating other CNS infections caused by antibiotic resistant gram-positive organisms.  相似文献   
84.
Gyrodactylids are ubiquitous ectoparasites of teleost fish, but our understanding of the host immune response against them is fragmentary. Here, we used RNA-Seq to investigate genes involved in the primary response to infection with Gyrodactylus bullatarudis on the skin of guppies, Poecilia reticulata, an important evolutionary model, but also one of the most common fish in the global ornamental trade. Analysis of differentially expressed genes identified several immune-related categories, including IL-17 signalling pathway and Th17 cell differentiation, cytokine-cytokine receptor interaction, chemokine signalling pathway, NOD-like receptor signalling pathway, natural killer cell-mediated cytotoxicity and pathways involved in antigen recognition, processing and presentation. Components of both the innate and the adaptive immune responses play a role in response to gyrodactylid infection. Genes involved in IL-17/Th17 response were particularly enriched among differentially expressed genes, suggesting a significant role for this pathway in fish responses to ectoparasites. Our results revealed a sizable list of genes potentially involved in the teleost-gyrodactylid immune response.  相似文献   
85.

Introduction and hypothesis

Our goal was to determine psychosexual outcome after labiaplasty in the long-term with specific measures of genital body image and sexual dysfunction.

Method

We conducted a prospective study with a matched-comparison group of women not wanting labiaplasty. Forty-nine women were compared against a group of 39 women matched for age, sexual orientation, ethnicity, and marital status. The labiaplasty group was assessed before, 3 months after and between 11 and 42 months after surgery. The comparison group was assessed at two time points 3 months apart to control for the passage of time. The primary outcome measure was the Genital Appearance Satisfaction (GAS) scale.

Results

Of the 49 women receiving labiaplasty, 19 (38.8 %) were lost to follow-up but were reassessed clinically. Twenty-four of 25 (96 %) women in the labiaplasty group showed a reliable and clinically significant improvement on the GAS scale 3 months after the procedure; 21/23 (91.3 %) showed an improvement at the long-term follow-up. A large effect size was found for improvements on the GAS scale in the labiaplasty group. Small-effect sizes were found for improvements in sexual functioning. Nine women obtaining labiaplasty met diagnostic criteria for body dysmorphic disorder before the operation; eight lost that diagnosis at the 3-month follow-up; 26 % reported minor side effects.

Conclusions

Labiaplasty is effective in improving genital appearance and sexual satisfaction, but larger studies are required to determine the prevalence of potential side effects.  相似文献   
86.
Desmoplastic small round cell tumors (DSRCTs) are highly aggressive sarcomas that most commonly occur intra‐abdominally, and are defined by EWSR1WT1 gene fusion. Intracranial DSRCTs are exceptionally rare with only seven previously reported fusion‐positive cases. Herein, we evaluate the clinical, morphologic, immunohistochemical and molecular features of five additional examples. All patients were male (age range 6–25 years; median 11 years), with four tumors located supratentorially and one within the posterior fossa. The histologic features were highly variable including small cell, embryonal, clear cell, rhabdoid, anaplastic and glioma‐like appearances. A prominent desmoplastic stroma was seen in only two cases. The mitotic index ranged from <1 to 12/10 HPF (median 5). While all tumors showed strong desmin positivity, epithelial markers such as EMA, CAM 5.2 and other keratins were strongly positive in only one, focally positive in two and negative in two cases. EWSR1WT1 gene fusion was present in all cases, with accompanying mutations in the TERT promoter or STAG2 gene in individual cases. Given the significant histologic diversity, in the absence of genetic evaluation these cases could easily be misinterpreted as other entities. Desmin immunostaining is a useful initial screening method for consideration of a DSRCT diagnosis, prompting confirmatory molecular testing. Demonstrating the presence of an EWSR1WT1 fusion provides a definitive diagnosis of DSRCT. Genome‐wide methylation profiles of intracranial DSRCTs matched those of extracranial DSRCTs. Thus, despite the occasionally unusual histologic features and immunoprofile, intracranial DSRCTs likely represent a similar, if not the same, entity as their soft tissue counterpart based on the shared fusion and methylation profiles.  相似文献   
87.
Advances in our understanding of the biological basis and molecular characteristics of ependymal tumors since the latest iteration of the World Health Organization (WHO) classification of CNS tumors (2016) have prompted the cIMPACT‐NOW group to recommend a new classification. Separation of ependymal tumors by anatomic site is an important principle of the new classification and was prompted by methylome profiling data to indicate that molecular groups of ependymal tumors in the posterior fossa and supratentorial and spinal compartments are distinct. Common recurrent genetic or epigenetic alterations found in tumors belonging to the main molecular groups have been used to define tumor types at intracranial sites; C11orf95 and YAP1 fusion genes for supratentorial tumors and two types of posterior fossa ependymoma defined by methylation group, PFA and PFB. A recently described type of aggressive spinal ependymoma with MYCN amplification has also been included. Myxopapillary ependymoma and subependymoma have been retained as histopathologically defined tumor types, but the classification has dropped the distinction between classic and anaplastic ependymoma. While the cIMPACT‐NOW group considered that data to inform assignment of grade to molecularly defined ependymomas are insufficiently mature, it recommends assigning WHO grade 2 to myxopapillary ependymoma and allows grade 2 or grade 3 to be assigned to ependymomas not defined by molecular status.  相似文献   
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90.
Aim:

Low-level laser therapy has still not been well established, and it is important to define a standardized protocol for the treatment of temporomandibular disorders (TMDs) using low level laser. There is no consensus on controlled clinical trials concerning the best option for laser therapy with regard to wavelength. The aim of this study was to evaluate the efficacy of red and infrared laser therapy in patients with TMD, using a randomized parallel-group double-blind trial.

Methodology:

Each hemiface of 19 subjects was randomized to receive intervention, in a total of 116 sensitive points. Pain was measured at baseline and time intervals of 24 hours, 30 days, 90 days, and 180 days after treatment. Irradiation of 4 J/cm2 in the temporomandibular joints and 8 J/cm2 in the muscles was used in three sessions.

Results:

Both treatments had statistically significant results (P<0·001); there was statistical difference between them at 180 days in favor of the infrared laser (P?=?0·039). There was improvement in 24 hours, which extended up to 180 days in both groups.

Conclusion:

Both lasers are effective in the treatment and remission of TMD symptoms.  相似文献   
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