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11.
Lucy Kean 《Current Obstetrics & Gynaecology》2006,16(4):199-205
Sadly, intrauterine fetal death is a common occurrence and one that all labour ward personnel should be trained to manage. Recent advances have improved the likelihood of identifying a cause. The key to this is a logical and methodical approach to investigation. Postmortem examination remains a critical aspect of investigation and labour ward teams require a clear understanding of the legal aspects of this. Sympathetic and supportive care of parents should respect parental wishes and allow choice wherever possible. However, maternal safety should also be a central aspect of this care. 相似文献
12.
Homicide inflicts massive injury upon the intrapsychic and interpersonal realities of the surviving kin of murder victims. A New York City pilot program of outreach and counselling to 1182 families of Brooklyn homicide victims suggests that surviving kin undergo the symptoms of traumatic stress disorder. Recovery is prolonged by knowledge that the perpetrator is usually alive and in some cases unpunished, by repetitive confrontations with the criminal justice system and by the multiple losses endured: loss of a family member, loss of illusions of safety and invulnerability, loss of a sense of trust in the surrounding community, and loss of a belief system. Effective help to survivors requires interventions that respond to all aspects of the survivors' losses. 相似文献
13.
Dr. Christopher G. Goetz Glenn T. Stebbins Lucy M. Blasucci Mitchell S. Grobman 《Movement disorders》1997,12(6):1039-1041
Patient on-off diaries are used in clinical trials, but a method to assure agreement between patient and examiner has never been developed. We tested whether a patient-teaching tape increased the rate of agreement between patient diary ratings and simultaneous neurologic assessment by a trained professional. A total of 32 consecutive patients who had Parkinson's disease with motor fluctuations independently completed a 4-h on-off diary (nine ratings) at the same time as an examiner. Those with <80% agreement with the examiner (n = 20) were randomized to view either a training tape that showed motor fluctuations (experimental group) or another videotape of general patient educational material (control group). All patients then underwent the same 4-h assessment of motor fluctuations. To test for long-term retention, they returned 1 month later and, without reviewing the videotape, underwent a final 4-h correlation assessment. After the training tape, the experimental group showed significant improvement, whereas the control group showed no improvement. Furthermore, another month later, the improvement in the experimental group was retained. Based on these findings, we suggest that future clinical trials assessing motor fluctuations incorporate this tape into their basic methodology. 相似文献
14.
Lucy SD Hughson RL Kowalchuk JM Paterson DH Cunningham DA 《Experimental physiology》2000,85(2):227-237
Neural mediation of the human cardiac response to isocapnic (IC) steady-state hypoxaemia was investigated using coarse-graining spectral analysis of heart rate variability (HRV). Six young adults were exposed in random order to a hypoxia or control protocol, in supine and sitting postures, while end-tidal PCO2 (PET,CO2) was clamped at resting eucapnic levels. An initial 11 min period of euoxia (PET,O2 100 mmHg; 13.3 kPa) was followed by a 22 min exposure to hypoxia (PET,O2 55 mmHg; 7.3 kPa), or continued euoxia (control). Harmonic and fractal powers of HRV were determined for the terminal 400 heart beats in each time period. Ventilation was stimulated (P < 0.05) and cardiac dynamics altered only by exposure to hypoxia. The cardiac interpulse interval was shortened (P < 0.001) similarly during hypoxia in both body positions. Vagally mediated high-frequency harmonic power (Ph) of HRV was decreased by hypoxia only in the supine position, while the fractal dimension, also linked to cardiac vagal control, was decreased in the sitting position (P < 0.05). However, low-frequency harmonic power (Pl) and the HRV indicator of sympathetic activity (Pl/Ph) were not altered by hypoxia in either position. These results suggest that, in humans, tachycardia induced by moderate IC hypoxaemia (arterial O2 saturation Sa,O2 85 %) was mediated by vagal withdrawal, irrespective of body position and resting autonomic balance, while associated changes in HRV were positionally dependent. 相似文献
15.
16.
Developmental regulation of the 5-HT7 serotonin receptor and transcription factor NGFI-A in the fetal guinea-pig limbic system: influence of GCs 总被引:1,自引:2,他引:1
17.
Expression of keratin K2e in cutaneous and oral lesions: association with keratinocyte activation,proliferation, and keratinization 下载免费PDF全文
Bloor BK Tidman N Leigh IM Odell E Dogan B Wollina U Ghali L Waseem A 《The American journal of pathology》2003,162(3):963-975
The cytoskeleton in keratinocytes is a complex of highly homologous structural proteins derived from two families of type I and type II polypeptides. Keratin K2e is a type II polypeptide that is expressed in epidermis late in differentiation. Here we report the influence of keratinocyte activation, proliferation, and keratinization on K2e expression in samples of cutaneous and oral lesions. The normal expression of K2e in the upper spinous and granular layers of interfollicular epidermis is increased in keloid scars but showed distinct down-regulation in psoriasis and hypertrophic scars where keratinocytes are known to undergo activation. Unlike normal and psoriatic skin, K2e expression in hypertrophic and keloid scars began in the deepest suprabasal layer. In cutaneous basal and squamous cell carcinomas, K2e was absent in most tumor islands but the overlying epidermis showed strong expression. No significant K2e expression in nonkeratinized or keratinized oral epithelia, including buccal mucosa, lateral border of tongue and gingiva was detected. In oral lichen planus K2e expression was undetectable, but in benign keratoses of lingual mucosa induction of K2e along with K1 and K10 was observed. In mild-to-moderate oral dysplasia with orthokeratinization, K2e was highly expressed compared with parakeratinized areas but in severe dysplasia as well as in oral squamous cell carcinoma, K2e expression was undetectable. Taken together, the data suggest that K2e expression in skin is sensitive to keratinocyte activation but its up-regulation in oral lesions is a reflection of the degree of orthokeratinization. 相似文献
18.
Comparison of PCR with the routine procedure for diagnosis of tuberculosis in a population with high prevalences of tuberculosis and human immunodeficiency virus 总被引:5,自引:0,他引:5 下载免费PDF全文
Kivihya-Ndugga L van Cleeff M Juma E Kimwomi J Githui W Oskam L Schuitema A van Soolingen D Nganga L Kibuga D Odhiambo J Klatser P 《Journal of clinical microbiology》2004,42(3):1012-1015
Direct smear examination with Ziehl-Neelsen (ZN) staining for the diagnosis of tuberculosis (TB) as employed in most low-income countries is cheap and easy to use, but its low sensitivity is a major drawback. The low specificity of chest X-rays, used for the diagnosis of smear-negative TB, risks high levels of overdiagnosis. Major advances in molecular techniques, which rapidly identify mycobacterial DNA in sputa, may overcome these obstacles. In this study, the AMPLICOR PCR system was used to diagnose pulmonary TB in a developing country with high prevalences of both TB and human immunodeficiency virus (HIV). The sensitivity and specificity of this technique were compared to those of the usual diagnostic techniques. Sputum specimens were collected from 1,396 TB suspects attending the Rhodes Chest Clinic, Nairobi, Kenya. The specimens were analyzed for the presence of Mycobacterium tuberculosis by PCR; culture on Löwenstein-Jensen medium was used as the “gold standard.” All culture-positive samples were genotyped to identify the mycobacterial species. The sensitivity and specificity of PCR were 93 and 84%, respectively. HIV status did not affect the sensitivity of PCR. A total of 99.7% of the true smear-positive and 82.1% of the true smear-negative TB patients were correctly identified by PCR. PCR detected M. tuberculosis in 11.7% of the culture-negative suspects, 60% of which had one or two PCR-positive sputum specimens. Of the 490 positive cultures, 486 were identified as M. tuberculosis. The high sensitivity of Amplicor PCR merits usage in a clinical setting with high TB and HIV burdens. Thus, PCR can be considered as an alternative to ZN staining in combination with chest X-ray for diagnosis of TB; however, cost-effectiveness studies and operational studies are required to support an evidence-based decision of introducing PCR for TB control in high-burden environments.Tuberculosis (TB) is one of the most serious infectious diseases and a considerable public health problem due to its high risk of person-to-person transmission, morbidity, and mortality. Both the human immunodeficiency virus (HIV) epidemic and social deterioration have contributed to the overall increase in the Mycobacterium tuberculosis infection rate, especially in developing countries, where resources are scarce (13). In Nairobi the case detection rate increased from 78 per 100,000 in 1991 to 581 per 100,000 in 2001, with a total number of 12,963 cases.Early diagnosis followed by adequate treatment is essential to prevent both morbidity and mortality. Although the conventional technique of direct smear examination with Ziehl-Neelsen staining (ZN) is cheap and easy to perform, its low sensitivity is a major drawback. Depending on the number of specimens examined, ZN detects 30 to 60% of the culture-positive “TB suspects” (7). Furthermore, it requires sputum samples collected on consecutive days, making the procedure slow and making patient compliance with the diagnostic process difficult.New techniques are very much needed (7), and molecular amplification assays such as PCR have been shown to be promising alternatives even for developing countries (2). PCR has the potential to be a cost-effective alternative, provided the diagnosis can be determined with one sputum examination (8). If diagnosis can be established faster, and the diagnostic process becomes less cumbersome for the patient, PCR may reduce delay both in diagnosis and in the start of treatment.Depending on the “gold standard” and other methodological factors, studies show PCR sensitivities ranging from 77% to more than 95% and PCR specificities of >95% for smear-positive specimens (4, 9, 10, 12). However, sensitivities for smear-negative TB patients have been reported to be below 90% (9). Most PCR studies have been performed in industrial countries (4, 9, 10, 12) where the TB and HIV burdens are low.To investigate the performance and feasibility of PCR in an environment of TB endemicity and high prevalences of HIV and AIDS, a study was conducted in Nairobi, Kenya, comparing PCR to conventional routine diagnostic methods within a program setup. In this study, the Roche Amplicor Mycobacteria PCR test for the direct detection of M. tuberculosis was used on sputum specimens from TB suspects attending a chest clinic in Nairobi. Its performance was compared with those of the basic routine diagnostic procedures according to the national guidelines (6), including clinical findings, ZN, and chest X-rays (CXR), on smear-negative suspects. Löwenstein-Jensen (LJ) culture results were used as the gold standard. 相似文献
19.
The Drosophila melanogaster proteins Flamingo and Prickle act in the planar cell polarity (PCP) pathway, which is required for acquisition of epithelial polarity in the wing, eye, and epidermis. In mammals, PCP signaling has been shown to regulate cell movements and polarity in a variety of tissues. Here, we show that the murine Flamingo orthologues Celsr1-3 and the Prickle orthologues Prickle1, Prickle2, and Testin have dynamic patterns of expression during pregastrulation and gastrulation stages. Celsr1 is expressed in the anterior visceral endoderm and nascent mesoderm, Celsr2 and Celsr3 mark the prospective neuroectoderm, Prickle1 is expressed in the primitive streak and mesoderm, Prickle2 in the node, and Testin in the anterior visceral endoderm, the extraembryonic ectoderm, primitive streak, and mesoderm. Analysis of a gene-trap mutation in Testin indicates that this gene is not required for embryogenesis; therefore, other Prickle homologues may compensate for its function during development. 相似文献
20.
Sugerman PB Faber SB Willis LM Petrovic A Murphy GF Pappo J Silberstein D van den Brink MR 《The American journal of pathology》2004,164(6):2189-2202
The kinetics of gene expression associated with the development of cutaneous graft-versus-host disease (GVHD) were examined in a mouse model of MHC-matched allogeneic hematopoietic stem cell transplantation. Ear skin was obtained from recipient mice with or without GVHD between 7 and 40 days after transplantation for histopathological analysis and gene expression profiling. Gene expression patterns were consistent with early infiltration and activation of CD8(+) T and mast cells, followed by CD4(+) T, natural killer, and myeloid cells. The sequential infiltration and activation of effector cells correlated with the histopathological development of cutaneous GVHD and was accompanied by up-regulated expression of many chemokines and their receptors (CXCL-1, -2, -9, and -10; CCL-2, -5, -6, -7, -8, -9, -11, and -19; CCR-1 and CCR-5), adhesion molecules (ICAM-1, CD18, Ly69, PSGL-1, VCAM-1), molecules involved in antigen processing and presentation (TAP1 and TAP2, MHC class I and II, CD80), regulators of apoptosis (granzyme B, caspase 7, Bak1, Bax, and BclII), interferon-inducible genes (STAT1, IRF-1, IIGP, GTPI, IGTP, Ifi202A), stimulators of fibroblast proliferation and matrix synthesis (interleukin-1beta, transforming growth factor-beta1), and markers of keratinocyte proliferation (keratins 5 and 6), and differentiation (small proline-rich proteins 2E and 1B). Many acute-phase proteins were up-regulated early in murine cutaneous GVHD including serum amyloid A2 (SAA2), SAA3, serpins a3g and a3n, secretory leukocyte protease inhibitor, and metallothioneins 1 and 2. The kinetics of gene expression were consistent with the evolution of cutaneous pathology as well as with current models of disease progression during cutaneous GVHD. 相似文献