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21.
The results of analysis of auditory brain- stem evoked responses (ABRS) are reported in 173 patients with delayed speech (DS). The mean age of the patients is 4.6 years (age ranges from 1.4 years to 10 years). The patients were classified into 5 groups based on ABR findings:
–  Group I (62 patients) had normal hearing threshold and peak- interpeak latencies. The mean amplitude of wave I was however, not significantly low (p < 0.03).
–  Group II (27 patients) had an increased hearing threshold (40 dB), mild delay in the mean absolute peak latency of wave I (p < 0.03), decreased I– IV interval (p < 0.03), but highly significant reduction of wave I amplitude (p < 0.004). There is also a significant latency delay (p < 0.001) and amplitude reduction (p < 0.05), when this wave is compared with that a Group I (as control). These observations are suggestive of mild degree of peripheral hearing deficit in this group.
–  Group III (49 patients) had gross ABR abnormalities of various nature and hence may be sub- grouped into (a) SNHL cochlear type (55%) (b) SNHL retrocochlear type (4%) and (c) severed degree of SNHL undecisive group (41%). Ten patients (2.7%) among the sub- group (a) had unilateral hearing loss and another 3 had Down’s syndrome.
–  Group IV (conductive deafness) had an increased hearing threshold and shifting of ABR waves towards right with normal I– V interval. Only 6 patients were found in this group. It may be that conductive deafness is less important as a cause.
–  Group V (29 patients) had no responses at repeated ABR studies even at higher intensity of 95 dB, the ABR studies of this group correlates with the clinical evaluation of profound deafness. The delayed speech development in 84 patients (from Groups III, IV and V) may be caused by severe degree of hearing deficit as indicated by marked ABR abnormalities. If the mild peripheral hearing loss in Group II is added to the above groups, ABRs could identify 64.6% of our patients with hearing deficit. Hence, ABR test is most reliable and sensitive diagnostic test in detecting hearing loss, a common cause of delayed speech development in children.
  相似文献   
22.
A strain of CLAVICEPS PURPUREA (F R.) T UL. isolated from ARTHRAXON LANCIFOLIUS H OCHST. was successfully adapted on rye. Experimental cultivation on rye showed 370 kg/ha yield of sclerotia containing 0.5% total alkaloid which consisted of 33% ergometrine, 17.6% ergotamine, 18.7% ergocornine and 22.7% ergokryptine. The results also reveal that alkaloid profile of the ergot strain depends largely on its host. Significantly high yield of the sclerotia and the valuable alkaloid profile of the new strain indicate its commercial potential.  相似文献   
23.
24.
OBJECTIVES: To conduct a phase I trial to determine the safety and toxicity profile of a novel immunomodulatory drug, lenalidomide, in recurrent ovarian and primary peritoneal cancer. The secondary objective is to evaluate the efficacy profile and quality of life (QOL) parameters in patients receiving this treatment. METHODS: Patients with recurrent ovarian or peritoneal cancer who received standard staging surgery and at least one prior platinum-based chemotherapy regimen were treated with single-agent oral lenalidomide 25 mg daily for 21 days of a 28-day cycle. Toxicities were monitored by patient report, physical exam, and laboratories. Response was assessed by imaging, physical exam, and CA-125. Therapy was discontinued with disease progression and/or unacceptable toxicity. RESULTS: 20 patients with recurrent ovarian or peritoneal cancer were enrolled and received 70 completed 28-day cycles and 10 partial cycles of lenalidomide therapy. The majority of adverse events were grades 1-2, including fatigue (25/80 cycles), nausea/vomiting (23/80), constipation (13/80), abdominal pain (17/80), rash (12/80), neutropenia (12/80), and anemia (12/80). Grade 3 toxicities occurred in 12 of 80 cycles (14%) and no grade IV toxicities were observed. Eleven patients completed > or = 2 cycles and were evaluable for response. Nine achieved stable disease (SD) of at least 3 months, with four patients maintaining SD for > 6 months. The mean time to progression was 5.8 months (range 2-12 months). CONCLUSION: Overall, oral lenalidomide was well tolerated and may have some activity as a single agent in this heavily pre-treated population. Further studies combining lenalidomide with cytotoxic treatments may be warranted in this disease setting.  相似文献   
25.
This work describes the preparation of an analytical microextraction sorbent using a simple and versatile sol–gel hybrid composite, i.e., aramid oligomers wrapping multi-walled carbon nanotubes (CNTs) covalently bonded to a porous silica network. To overcome the inherent shortcomings of the CNTs'' solubility and dispersion in both organic phases and in the sol–gel solution, the outer surface of the CNTs was initially functionalized with carboxylic acid groups and then reacted with both aramid oligomers and 3-aminopropyl triethoxysilane (APTES). The obtained sorbent was characterized by FT-IR, scanning electron microscopy (SEM), and thermogravimetric analysis (TGA). Using sol–gel chemistry, the functionalized CNTs were coated onto SPME fibers and used in conjunction with GC-MS for the analysis of polycyclic aromatic hydrocarbons (PAHs) in water and soil samples. Excellent repeatability (run-to-run RSD% ∼ 8) and reproducibility (fiber-to-fiber RSD% ∼ 6) were achieved in addition to low LODs (0.10–0.30 ng mL−1) and noticeable recovery%. The present method of sorbent preparation led to enhanced thermal and chemical stabilities, a long sorbent lifetime and good affinity towards PAHs. Moreover, the present sorbent enhanced the extraction capability by more than 30% compared to that of commercially available PDMS counterparts.

This work describes the preparation of an analytical microextraction sorbent using a simple and versatile sol–gel hybrid composite, i.e., aramid oligomers wrapping multi-walled carbon nanotubes (CNTs) covalently bonded to a porous silica network.  相似文献   
26.
Functional magnetic resonance imaging (fMRI) techniques allow definition of cortical nodes that are presumed to be components of large-scale distributed brain networks involved in cognitive processes. However, very few investigations examine whether such functionally defined areas are in fact structurally connected. Here, we used combined fMRI and diffusion MRI-based tractography to define the cortical network involved in saccadic eye movement control in humans. The results of this multimodal imaging approach demonstrate white matter pathways connecting the frontal eye fields and supplementary eye fields, consistent with the known connectivity of these regions in macaque monkeys. Importantly, however, these connections appeared to be more prominent in the right hemisphere of humans. In addition, there was evidence of a dorsal frontoparietal pathway connecting the frontal eye field and the inferior parietal lobe, also right hemisphere dominant, consistent with specialization of the right hemisphere for directed attention in humans. These findings demonstrate the utility and potential of using multimodal imaging techniques to define large-scale distributed brain networks, including those that demonstrate known hemispheric asymmetries in humans.  相似文献   
27.
Objective  This is the first report of the simultaneous combined use of trans-sphenoidal and trans-ventricular-endoscopic route for decompression of a giant pituitary adenoma. Method  A 38 year old man presented to us with symptoms of raised intracranial pressure along with visual and hypothalamic disturbances. The CT scan revealed destruction of the sella by a large (5 × 3.5 × 2.5 cm) well defined enhancing mass in the sella and suprasellar region extending laterally up to the cavernous sinuses and both carotid arteries and superiorly into the lumen of the 3rd ventricle producing obstructive hydrocephalus. On T2WI of the non-contrast MRI scan the mass was iso-intense to grey matter suggesting the possibility of a firm nature of the adenoma. The tumour was first approached by the standard trans-sphenoidal route and as predicted from the pre-operative MRI, the tumour was found to be firm and not amenable to suction. After decompression of the intra-sellar part of the tumour, the intracranial pressure was raised in an attempt to make the remainder of the tumour descend into the sella but without success. The suprasellar part of the tumour was then simultaneously addressed via a trans-ventricular-endoscopic route but the firm tumour did not yield to endoscopic instruments viz. biopsy forceps, angiographic catheter and electrosurgical probes. It was then gently pushed down towards the sella and decompressed piecemeal by using trans-sphenoidal instruments. The sellar cavity was reconstructed using fat, fascia lata graft and a piece of septal bone. Results  Post-operatively, the patient showed a remarkable improvement of his symptoms of raised intracranial pressure, hypothalamic dysfunction and visual disturbances. Follow-up imaging at 2 months and 1 year, did not show any residual or recurrent tumour. Conclusions  This novel technique of the combined trans-sphenoidal and simultaneous trans-ventricular-endoscopic approach is a viable option for patients with giant fibrous pituitary adenoma when the tumour is not yielding to the trans-sphenoidal route alone.  相似文献   
28.

Background

Metaphyseal forearm fractures are a common pathology in any emergency department. The standard diagnostic procedure involves X-rays of the forearm and wrist. As former studies have shown that these fractures can be visualized using ultrasound, we compared the accuracy of sonographic and X-ray diagnostics.

Methods

From January 2007 to May 2008, a total of 93 patients aged between 0 and 12 years with forearm trauma were initially examined using a 7.5-Mhz linear transducer. After diagnosis, axis deviation and treatment were fixed and standard X-rays were taken. The results of the two diagnostic procedures were compared. The examiners were doctors in training or consultants and underwent no specific training.

Results

We found 77 fractures in 64 patients (50 radius, 1 ulna, 13 radius and ulna). The sensitivity of ultrasound diagnostics was 94% and the specificity 99% compared with X-ray diagnosis. Mean axis deviation differences were 1.8° (radius) and 0.7° (ulna).

Conclusion

Ultrasound seems to be a valuable and safe alternative to X-ray diagnosis. Patients with inconclusive findings should undergo X-ray diagnosis.  相似文献   
29.
Investigation of the bypassed stomach in patients with suspected peptic ulcer disease presents a major challenge to bariatric surgeons. Various methods have been suggested for visualization of the duodenum and bypassed stomach. These include endoscopy via percutaneous gastrostomy access, retrograde endoscopy and virtual gastroscopy using CT scan. We present a case of peptic ulcer bleeding diagnosed with the help of conventional CT scan. To the best of our knowledge, this is the second such case reported in the literature and the first in the bariatric population.  相似文献   
30.
Profound T-cell depletion with the monoclonal antibody alemtuzumab facilitates reduced maintenance immunosuppression in abdominal and lung transplantation. While the phenotype of the post-depletional T cells has been characterized, little is known about their function. In the present study, global and CMV-specific T-cell function was assessed longitudinally in 23 lung transplant (LTx) recipients using T-cell assays (ImmuKnow and T Cell Memory, Cylex, Columbia, MD) during the first year posttransplant after induction therapy. Recovery of mitogen responses were seen at 2 weeks posttransplantation (65%PHA; 58% Con A), despite the low number of circulating T cells (<2%). These responses declined at 4-5 months (24%PHA; 54% Con A) and were partially reconstituted by 9 months (46% PHA; 73% Con A). CMV-specific responses recovered in 80% of R+ patients as early as 2 weeks posttransplant (n = 5) and 72% of patients had a memory response by 3 months (n = 11). In contrast, only 2 of 5 patients who did not exhibit memory responses pre-transplant (R-) developed transient CMV-specific T-cell responses. Our results show that profound depletion of T cells induced by alemtuzumab spares the functional subset of CMV-specific memory T cells. Conversely, CMV R- patients predepletion may require a prolonged period of prophylaxis.  相似文献   
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