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71.
The performance of the BD Phoenix Automated Microbiology System (BD Diagnostic Systems, Sparks, Md.) was assessed for identification (ID) and antimicrobial susceptibility testing (AST) for the majority of clinically encountered bacterial isolates in a European collaborative two-center trial. A total of 469 bacterial isolates of the genera Staphylococcus (275 isolates), Enterococcus (179 isolates), and Streptococcus (15 isolates, for ID only) were investigated; of these, 367 were single patient isolates, and 102 were challenge strains tested at one center. Sixty-four antimicrobial drugs were tested, including the following drug classes: aminoglycosides, beta-lactam antibiotics, beta-lactam-beta-lactamase inhibitors, carbapenems, cephems, folate antagonists, quinolones, glycopeptides, macrolides-lincosamides-streptogramin B (MLS), and others. Phoenix ID results were compared to those of the laboratories' routine ID systems (API 32 Staph, API 32 Strep, and VITEK 2 [bioMérieux, Marcy l'Etoile, France]); Phoenix AST results were compared to those of frozen standard broth microdilution (SBM) panels according to NCCLS guidelines (NCCLS document M 100-S 9, approved standard M 7-A 4). Discrepant results were repeated in duplicate. Concordant IDs of 97.1, 98.9, and 100% were observed for staphylococci, enterococci, and streptococci, respectively. For AST results the overall essential agreement was 93.3%; the category agreement was 97.3%; and the very major error rate, major error rate, and minor error rate were 1.2, 1.9, and 1.3%, respectively. In conclusion, the Phoenix ID results showed high agreement with results of the systems to which they were being compared; the AST performance was highly equivalent to that of the SBM reference method.  相似文献   
72.
We have constructed a contig of non-chimaeric yeast artificialchromosomes (YACs) across the candidate region for childhoodautosomal recessive spinal muscular atrophy (SMA) In 5q13. Anovel microsatellite reduces the candidate region to approximately400kb of DNA distal to D5S435. The candidate region containsblocks of chromosome 5 specific repeats which have copies on5p as well as elsewhere on 5q. Restriction mapping of the YACsreveals at least one CpG island In the SMA gene region. TheYAC maps indicate that the contig contains minimal rearrangementsor deletions. The data show the value of screening several YAClibraries simultaneously in order to construct a set of overlappingsequences suitable for candidate gene searches and direct genomicsequencing.  相似文献   
73.
Summary The 5-hydroxytryptamine (5HT) receptor agonist, 5-methoxytryptamine, inhibited in a concentration-dependent manner the electrically-evoked release of 3H-5HT from superfused rat hypothalamic slices, with an IC50 of 560 nmol/l, without affecting the spontaneous outflow of radioactivity. In the presence of the selective monoamine oxidase B (MAO B) inhibitor, (–)-deprenyl (1 mol/l), the concentration-effect curve for 5-methoxytryptamine was shifted significantly to the left, and the IC50 was decreased to 25 nmol/l. Under the same experimental conditions, the potency of the 5HT receptor agonist lysergic acid diethylamide (LSD) at inhibiting the electrically-evoked release of 3H-5HT was the same in the presence as well as in the absence of (–)-deprenyl. The IC50 values for LSD were 34 nmol/l in the absence of deprenyl, and 31 nmol/l in the presence of the MAO B inhibitor. It is concluded that deprenyl potentiates the inhibition by 5-methoxytryptamine of 3H-5HT release, by preventing its inactivation through MAO B. Since 5-methoxytryptamine may be present in the pineal gland of some species, the potent effects of this 5-HT receptor agonist on seretoninergic neutrotransmission may be of physiological relevance.  相似文献   
74.
Breast fat necrosis (BFN) is usually a benign inflammatory response to breast trauma. However, an extremely rare cause of fat necrosis is calciphylaxis, a calcification of small- and medium-sized arteries causing thrombosis and ischemia. It is classified into (A) uremic (B) nonuremic-induced calciphylaxis. Calciphylaxis has been reported to be encountered in different parts of the body. However, to the best of our knowledge there is only one case in the English literature of BFN 2ry to warfarin-induced calciphylaxis. We report a 65-year-old female, known case of atrial fibrillation on warfarin, presented with a left breast mass of 4-month duration. The mass was painful and progressively enlarging. Examination of the left breast showed 7 × 4 cm mass, spanning from 10-2 o'clock, free from surrounding structures, with preserved overlying skin. However, the mass was not visualized on mammogram. Ultrasound showed a left breast lobulated hypoechoic mass containing a hyperechoic component. Biopsy showed fat necrosis. After 1 month, she presented with ulceration of the overlying skin. After wide local excision, histopathology demonstrated a calciphylaxis-induced fat necrosis. Considering the patient's background, the diagnosis was BFN secondary to warfarin-induced calciphylaxis. Hence, the warfarin was shifted to Rivaroxaban, 6 months follow-up showed no evidence of recurrence. In conclusion, the rarity of nonuremic calciphylaxis is reflected on the delay of diagnosis in some of the reported cases and the lack of grading system used to guide the management of such difficult wounds. However, keeping a high index of suspicion is important whenever such wounds are encountered with presence of risk factors other than end-stage kidney disease.  相似文献   
75.
Rhabdomyosarcoma (RMS) is a common malignancy in children, but embryonal rhabdomyosarcoma (ERMS) deposits rarely occur in the breast in adults. Therefore, little is known about magnetic resonance imaging (MRI) features of breast metastases from RMS, especially the embryonal type. We reported a case of a 22-year-old woman who was diagnosed with ERMS at left foot 2 years ago and accepted operation and chemotherapy. She was confirmed to have breast metastases from the left foot. Successive imaging examinations were performed 3 months apart. Breast ultrasound indicated a benign lesion, and further examination did not reveal any bone metastases. However, predominant restricted diffusion and rim contrast enhancement on MRI combined with the patient's medical history suggested a malignancy of BI-RADS 5. After 3 months, breast ultrasound revealed masses detected last time became larger and lobulated. In addition, internal heterogeneous intensity and rim contrast enhancement with restricted diffusion were revealed on MRI. We speculated that typical MRI findings of breast metastases from RMS may include iso- to hypointensity on T1WI, heterogeneous hyperintensity on T2WI, and circular enhancement with restricted diffusion. Moreover, mild peritumoral edema, rapid expansion of necrosis, and ascending time-intensity curve detected on MRI may be features of the ERMS type.  相似文献   
76.
Self-care enables patients in improving quality of life and reducing hospital admissions. Research explored the experiences of patients about breathlessness, sleep problems and complication management in chronic obstructive pulmonary disease (COPD). However, the self-care experiences and the role of the family in self-care are underexplored. This study aimed to understand the self-care experiences of patients with COPD and explore the role of the family in self-care. An interpretive phenomenological inquiry was used, and 13 patients were interviewed in 2019 from two hospitals in Pakistan. The inclusion criteria were patients above 30 years of age at any stage of COPD, who received a confirmed diagnosis of COPD and were receiving the treatment, and engaged in self-care at their homes or communities. The interviews lasted for 35–60 min. Ricoeur's interpretation theory was used for data analysis comprising steps explanation, naive understanding and in-depth understanding. Self-care emerged as a complex individual and familial endeavour affected by personal, social and economic factors. Poverty was one of the core determinants of self-care. Patients emphasised the spiritual, cultural and traditional approaches to self-care. Future research is warranted to develop better understanding of spiritual and cultural self-care and how these dimensions of self-care affect patients’ self-care behaviours.  相似文献   
77.
Young people from migrant and ethnic minority backgrounds are recognised as emerging priority populations for reducing alcohol and other drug (AOD)-related harms in Australia. Limited research has investigated how service providers address AOD challenges in migrant communities. In this qualitative study, we interviewed 15 service providers from AOD, migrant support, community and other health services in a diverse region of Melbourne. Interviews explored the challenges that service providers faced and the strategies they implemented to engage with young migrants in relation to AOD use. Thematic analysis was used to generate four themes: stigma as a barrier to service delivery, intergenerational differences between young people and parents, the need for outreach and establishing trust and understanding over time. Service providers believed that stigma prevented many young people from migrant backgrounds having open conversations about their AOD use with family members and professionals. Participants perceived that some parents had less AOD-related knowledge and lower English language proficiency than their children creating challenges for effective communication. Service providers recognised the importance of engaging with young people in settings where they felt comfortable rather than expecting them to approach their service. Participants also acknowledged the need to invest time in establishing trust and understanding with young migrants so they could facilitate conversations about AOD use as relationships evolved. Although service providers had a strong understanding of young people's needs, they found it challenging to build relationships in the context of funding and time constraints. Our results indicate the need for long-term funding and timelines that enable service providers to build strong relationships with young migrants, their families and their broader cultural communities to facilitate access to AOD support.  相似文献   
78.
The neu-protein is overexpressed in about 20% of invasive duct cell carcinomas of the breast. The only reliable sign for neu-overexpression by immunohistochemistry is membrane staining. Its overexpression is correlated with decreased overall survival and disease free survival due to increased metastatic activity of neu-overexpressing tumour cells. This increased metastatic potential is a consequence of the motility enhancing activity of the neu-protein, which is exclusively expressed on pseudopodia, and to a lesser extent of its growth stimulating effect. From a clinical point of view, the assessment of neu-overexpression in breast cancer might become a useful tool in the future treatment of patients by chemotherapy, since patients whose tumour shows neu-overexpression benefit from higher doses of chemotherapy. The molecule plays a key role in the pathogenesis of Paget's disease of the breast. A chemotactic factor which is secreted by epidermal keratinocytes attracts the Paget cells to spread into the epidermis and acts via the neu-protein. In ductal carcinoma in situ, the combination of neu-overexpression and large cell type is highly correlated with extent of disease and therefore neu-overexpression might be a predictive marker for recurrence of disease after tumour resection.  相似文献   
79.
It has been suggested that the renal functional reserve (RFR) defined by the rise in glomerular filtration rate (GFR) after a protein load could disappear in patients with severe nephron loss but with a normal GFR. This study compared, in 17 children, inulin clearance (C in) measured by the plasma inulin plateau at the end of two 14-day randomized periods differing in protein intake: 100% (low protein, LP), or 200% (high protein, HP) of recommended dictary allowances (RDA). Diets were aimed at maintaining food habits and energy intake. Compliance was assessed by records of the last 3–4 days, an interview with the dietician and by urinary nitrogen measurements. Mean actual protein intake was 109% (56%–139%) RDA for the LP period and 220% (163%–319%) RDA for the HP period.C in did not change in 14 children with GFR below (n=7) or within (n=7) the normal range.C in was higher in the HP period than in the LP period (+32, 50, 63%) in 3 children who had a 50% (single kidneys) or a 25% (sclerosed glomeruli) nephron loss. Non-responding children had a GFR below 105 ml/min per 1.73 m2. Nephron loss (70% sclerosed glomeruli) was estimated in only 1 child with no RFR. The results suggest that GFR measurement after prolonged dietary stimulation could help in evaluating the severity of nephron loss in children with normal or borderline GFR. The prognostic value of this test has to be confirmed by long-term follow-up.  相似文献   
80.
  1. The effects of zidovudine (ZDV) and zidovudine triphosphate (ZDV-3P) on Ca2+-induced mitochondrial permeability transition (MPT), respiratory control ratio (RCR) and ATP synthesis have been investigated on isolated rat liver mitochondria.
  2. ZDV slightly but significantly decreased RCR and ATP synthesis but was ineffective in inhibiting MPT. In contrast, ZDV-3P did not alter RCR and ATP synthesis but strongly inhibited MPT (IC50=3.0±0.9 μM).
  3. The effect of ZDV-3P on mitochondrial swelling required a preincubation time. When incubated 10 min with mitochondria, ZDV-3P (8 μM) totally inhibited the rate of swelling.
  4. ADP, ATP and atractyloside, which are agents known to interact with the mitochondrial adenine nucleotide carrier (ANC), antagonized the effect of ZDV-3P on mitochondrial swelling. Indeed, the IC50 value of ZDV-3P increased from 3.0 to 17.4, 93.6 and 66.5 μM, in the presence of 20 μM, ADP, ATP or atractyloside, respectively.
  5. ZDV-3P did not displace [3H]-ATP from its mitochondrial binding site(s) whereas ADP and atractyloside did, suggesting that ZDV-3P and [3H]-ATP do not share the same binding sites.
  6. ZDV-3P did not affect either mitochondrial respiration or ATP synthesis but inhibited Ca2+-dependent mitochondrial swelling. It was concluded that mitochondrial toxic effects observed during the chronic administration of ZDV cannot be related to its active metabolite (ZDV-3P).
  相似文献   
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