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A prospective, randomized study was conducted to evaluate the thickness, of zona pellucida (ZP) after brief or standard exposure of human oocytes to spermatozoa, and to determine the correlation between ZP thickness, fertilization rate and embryo quality. The mean ZP thickness 48 h after insemination was found to be significantly less in fertilized oocytes than in non-fertilized oocytes in all treated groups (13.72 +/- 3.0 microns and 15.08 +/- 2.5 microns, respectively; p < 0.007). Zona pellucida thickness correlated positively with embryo quality. Brief exposure of gametes was found to influence ZP thickness. The ZP was significantly thinner after brief and intracytoplasmic sperm injection (ICSI) exposure of oocytes to spermatozoa than after standard in vitro fertilization (IVF). The mean ZP thickness 24 and 48 h after fertilization was significantly greater in standard IVF (16.43 +/- 2.8 microns and 15.22 +/- 2.7 microns, respectively) than in either the brief exposure or ICSI groups (12.78 +/- 2.4 microns and 13.01 +/- 3.5 microns vs. 13.46 +/- 2.2 microns and 13.16 +/- 2.4 microns; p < 0.0001).  相似文献   
94.
Objectives: To determine the effectiveness of Problem-Solving Therapy (PST) in older hemodialysis (HD) patients by assessing changes in health-related quality of life and problem-solving skills.

Methods: 33 HD patients in an outpatient hemodialysis center without active medical and psychiatric illness were enrolled. The intervention group (n = 15) received PST from a licensed social worker for 6 weeks, whereas the control group (n = 18) received usual care treatment.

Results: In comparison to the control group, patients receiving PST intervention reported improved perceptions of mental health, were more likely to view their problems with a positive orientation and were more likely to use functional problem-solving methods. Furthermore, this group was also more likely to view their overall health, activity limits, social activities and ability to accomplish desired tasks with a more positive mindset.

Conclusions: The results demonstrate that PST may positively impact mental health components of quality of life and problem-solving coping among older HD patients.

Clinical Implications: PST is an effective, efficient, and easy to implement intervention that can benefit problem-solving abilities and mental health-related quality of life in older HD patients. In turn, this will help patients manage their daily living activities related to their medical condition and reduce daily stressors.  相似文献   

95.
DNA amplification, manifested by homogeneously staining regions in chromosomes and by extrachromosomal, double minute bodies, is characteristic of many neuroblastoma cell lines. Sequences recruited from a specific domain on the short arm of chromosome 2 (2p) are amplified in advanced-stage primary neuroblastomas, whereas sequences from distinctly different regions of 2p are amplified in the neuroblastoma cell line IMR-32. Five different DNA segments, which include the oncogene N-myc, three other fragments derived from the homogeneously staining region of the neuroblastoma cell line IMR-32, and a fifth fragment, derived from the neuroblastoma cell line NB-9, showed differential and variable amplification in 24 advanced-stage neuroblastoma tumors out of 112 tested specimens. All five fragments were mapped within the chromosomal region 2p23-2p25 by three different approaches. However, eight other fragments cloned from the homogeneously staining region of IMR-32 cells, which were not amplified in the tumor tissues examined, were mapped to two more proximal domains of 2p, thousands of kilobases apart from each other and from the chromosomal domain that is amplified in the tumors. These results establish the amplification, to different degrees, of a variable-sized segment of one domain near the terminus of 2p in advanced neuroblastomas. These tumors might ultimately be distinguished according to the pattern of amplification of DNA segments within this domain. The data presented also indicate the existence of a new and complex amplification mechanism in at least one neuroblastoma cell line (IMR-32), which involves not only relocation of DNA from specific genomic domains but also the formation of novel units by splicing together very distant DNA segments.  相似文献   
96.
Islam  Marjan  Levitus  Matthew  Eisen  Lewis  Shiloh  Ariel L.  Fein  Daniel 《Lung》2020,198(1):1-11

For critically ill patients with acute respiratory failure (ARF), lung ultrasound (LUS) has emerged as an indispensable tool to facilitate diagnosis and rapid therapeutic management. In ARF, there is now evidence to support the use of LUS to diagnose pneumothorax, acute respiratory distress syndrome, cardiogenic pulmonary edema, pneumonia, and acute pulmonary embolism. In addition, the utility of LUS has expanded in recent years to aid in the ongoing management of critically ill patients with ARF, providing guidance in volume status and fluid administration, titration of positive end-expiratory pressure, and ventilator liberation. The aims of this review are to examine the basic foundational concepts regarding the performance and interpretation of LUS, and to appraise the current literature supporting the use of this technique in the diagnosis and continued management of patients with ARF.

  相似文献   
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The cerebellum is exquisitely sensitive to deficiencies in the cellular response to specific DNA lesions. Genetic disorders caused by such deficiencies involve relentless, progressive cerebellar atrophy with striking loss of Purkinje and granule neurons. The reason for the extreme sensitivity of these cells to defective response to certain DNA lesions is unclear. This is particularly true for ataxia-telangiectasia (A-T) – a genomic instability syndrome whose major symptom is cerebellar atrophy. It is important to understand whether the DNA damage response in the cerebellum, particularly in Purkinje neurons, has special characteristics that stem from the unique features of these cells. Murine cerebellar organotypic cultures provide a valuable experimental system for this purpose since they retain the tissue organization for several weeks in culture and appear to provide the delicate Purkinje neurons with a physiological environment close to that in vivo. We have optimized this system and are using it to examine the Atm-mediated DNA damage response (DDR) in the cerebellum, with special emphasis on Purkinje cells. Our results to date, which indicate special chromatin organization in Purkinje cells that affects certain pathways of the DDR, demonstrate the usefulness of cerebellar organotypic cultures for addressing the above questions.  相似文献   
99.
Increasing evidence suggests that the cholinergic system is involved in the pathogenesis of schizophrenia. Donepezil, a central cholinesterase inhibitor, improves psychotic symptomatology in demented patients, however, evidence for its role in the management of active psychosis in schizophrenia remains limited. An 18-week double blind cross-over study was conducted in which eight patients were randomly assigned to either donepezil (5 mg/day for the first 4 weeks and 10 mg/day for the following 4 weeks) or placebo as augmentation treatment to clozapine. After this initial phase, there was a 2-week washout period of the study medication after which the same regimen was crossed over at the same dose and for the same period (8 weeks). No significant difference was noted in the total positive and negative symptom scale scores when donepezil was compared with placebo (16.7%+12.97% vs 3.20%+13.94% respectively, p = 0.18). However, three patients improved (>15%) in the total PANSS scores (37.03%, 16.6% and 25.33%) during the donepezil treatment phase, while only one patient improved (20.87%) during the placebo phase. No differences were noted in the Calgary depression scale (p = 0.305), Simpson Angus scale (p = 0.374), clinical global impression-improvement scale (p = 0.23) and clinical global impression-severity of illness scores (p = 0.116). Although this preliminary study failed to demonstrate a clear effect of donepezil augmentation in clozapine treated chronic schizophrenia patients, it seems that the subtle positive effect of donepezil observed in some of our patients should encourage further investigation in a larger sample of this patient subpopulation.  相似文献   
100.
IntroductionPreliminary point-prevalent data suggest that drug-free schizophrenia patients may exhibit increased body/corneal temperature, that antipsychotic drugs (APDs) may decrease body/core temperature and that patients' mental status might be associated with their body/corneal temperature. Hence, we hypothesized that treatment-resistant psychotic APD-treated schizophrenia patients' mental status may correlate with their corneal temperature during a continuous 6-week period.MethodsCorneal temperature of 12 treatment-resistant schizophrenia inpatients and 16 healthy volunteers was evaluated 2–3 times a week during 6 consecutive weeks using a flir thermal imaging camera.ResultsA significant and substantial correlation was found between inpatients' mean weekly Positive and Negative Syndrome Scale (PANSS)'s total scores and their mean weekly corneal temperature during the 6-week study period (r = 0.82; n = 6 weeks; p = 0.043). There was no significant difference in mean 6-week corneal temperature between the patient group and the healthy subjects (34.25 ± 0.64 °C vs. 34.39 ± 0.69 °C, respectively; t = 1.127, df = 131, p = 0.26).ConclusionsThis study indicates that treatment-resistant overtly psychotic schizophrenia inpatients' mental status (as assessed by the PANSS) correlates with their corneal temperature. The relevance of these phenomena to the pathophysiology of schizophrenia, the biological mechanism underlying corneal temperature alterations and the possible role of temperature-modulating drugs (neuroleptics or non-neuroleptics) on schizophrenic psychosis merits further large-scale investigation in both medicated- and drug-free schizophrenia patients compared to matched controls.  相似文献   
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