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91.
Swallowing must interact with respiration so that a swallow causes minimal or no disturbance of continual respiration. In order to study the coordinate control of swallowing and respiration, we investigated the effects of spontaneous and water-induced swallows on the pattern of ongoing respiration in 8 adult human subjects. Swallows were identified by submental electromyograms and visual observation of the characteristic laryngeal movements. Both spontaneous and water-induced swallows occurred during all phases of the respiratory cycle, but approximately 80% of swallows occurred during the expiratory phase. No essential difference between spontaneous and water-induced swallows in the effects of the swallowing on respiration was observed. A swallow coinciding with the expiratory phase prolonged the duration of the same expiration that had been interrupted, whereas a swallow coinciding with the inspiratory phase interrupted the inspiration immediately and was followed by a short expiratory duration. There was a positive correlation between the time from the onset of the expiration to the onset of the swallowing and the duration of the expiration interrupted by the swallowing, indicating that the later the onset of the swallowing takes place, the more is the expiration prolonged. The duration of respiratory cycle in the breaths immediately following the swallow was not affected by the swallow, but there was a considerable increase in the tidal volume of the postswallowing breaths. These results suggest that the changes in respiratory pattern induced by the act of swallowing may depend on some mechanism that regulates the coordination of respiration and swallowing.  相似文献   
92.
A 54-year old female patient presented with intracranial tuberculoma attached to the dura mater during treatment with anti-tuberculous agents. Compared tomography (CT) and magnetic resonance imaging (MRI) revealed a lesion resembling a cystic meningioma. A granulomatous tumor that adhered to the cerebral cortex and dura was totally removed. Histological diagnosis was epithelioid granuloma. After removal of the tuberculoma and treatment with anti-tuberculous medications, the patient seemed to be cured, and regrowth of the tumor has not been observed to date. Tuberculoma mimicking meningioma is a very rare phenomenon. In the present study, we review intracranial tuberculomas and discuss their radiological features.  相似文献   
93.
An ultracompact, completely implantable permanent use electromechanical ventricular assist device (VAD) and total artificial heart (TAH) intended for 50-60 kg size patients have been developed. The TAH and VAD share a miniature electromechanical actuator that comprises a DC brushless motor and a planetary roller screw. The rotational force of the motor is converted into the rectilinear force of the roller screw to actuate the blood pump. The TAH is a one piece design with left and right pusher plate type blood pumps sandwiching an electromechanical actuator. The VAD is one half of the TAH with the same actuator but a different pump housing and a backplate. The blood contacting surfaces, including those of the flexing diaphragm and pump housing, of both the VAD and TAH were made of biocompatible polyurethane. The diameter, thickness, volume, and weight of the VAD are 90 mm, 56 mm, 285 cc, and 380 g, respectively, while those of the TAH are 90 mm, 73 mm, 400 cc, and 440 g, respectively. The design stroke volume of both the VAD and TAH is 60 cc with the stroke length being 12 mm. The stroke length and motor speed are controlled solely based on the commutation signals of the motor. An in vitro study revealed that a maximum pump flow of 7.5 L/min can be obtained with a pump rate of 140 bpm against a mean afterload of 100 mm Hg. The power requirement ranged from 4 to 6 W to deliver a 4-5 L/min flow against a 100 mm Hg afterload with the electrical-to-hydraulic efficiency being 19-20%. Our VAD and TAH are the smallest of the currently available devices and suitable for bridge to transplant application as well as for permanent circulatory support of 50-60 kg size patients.  相似文献   
94.
We longitudinally studied whether vitamin D receptor (VDR) and estrogen receptor (ER) gene polymorphisms in Japanese women influenced the effect of longterm hormone replacement therapy (HRT) on bone mineral density (BMD) in the lumbar spine. The 81 subjects were aged 40 to 64 years (mean ± SEM, 49.5 ± 0.6 years), and had received sequential or continuous HRT regimens, including 0.625mg of conjugated equine estrogen and 2.5 to 5mg of medroxy-progesterone acetate, for at least 3 years. Genomic DNA was extracted from blood cells, and analyzed for restriction fragment length polymorphism, using the restriction endonucleases Taq I, Apa I, and Fok I for VDR, and Pvu II and Xba I for ER. At 1 year, subjects with a Taq I genotype of TT (i.e., site absent) showed a significantly greater increase in BMD with treatment (BMD) than subjects with the Tt genotype (2.6 ± 0.5% vs –0.8 ± 1.4%; P = 0.016). A small difference between genotypes remained at 2 years (3.8 ± 0.6% vs 0.8 ± 1.6%; P = 0.069), but no significant difference between genotypes was seen at 3 years. In multiple regression analyses, BMD at 1 year was significantly affected by VDR-Taq I, Apa I, and ER-Pvu II genotypes and by age at treatment initiation, although at 3 years or more, BMD was significantly affected only by age. These results indicate that Taq I VDR gene polymorphism predicted the effect on lumbar BMD for the first year of HRT in Japanese women, and that the differences in BMD versus the polymorphism disappeared if the treatment was continued for over 2 years.  相似文献   
95.
96.
BACKGROUND AND PURPOSE: Although digital subtraction angiography (DSA) is considered the criterion standard for depiction of intracranial aneurysms, it is often difficult to determine the relationship of overlapping vessels to aneurysms when using 2D DSA. We compared 2D and 3D DSA in evaluation of intracranial aneurysms. METHODS: Thirty-six consecutive patients with cerebral aneurysms underwent 2D and 3D DSA. After standard 2D DSA, rotational DSA was performed. Maximum intensity projection (MIP) and shaded surface display (SSD) images were created from the rotational DSA data sets. All images were assessed randomly for overall image quality, presence of aneurysm, presence of aneurysmal lobulation, visualization of aneurysmal neck, and relationship to adjacent vessels. Data analysis was conducted for 40 aneurysms treated by clip placement. RESULTS: One aneurysm that was not detected at 2D DSA was classified as uncertain on the basis of rotational DSA. All aneurysms were classified as probably or definitively present on the basis of MIP and SSD findings. Overall image quality of rotational DSA, MIP, and SSD was statistically inferior to that of the standard 2D DSA for visualization of distal arteries. However, MIP and SSD images were significantly superior to those of standard 2D DSA for all other evaluations. For detection of lobulation, SSD images were significantly superior to other images, and for visualization of aneurysmal neck and relationship to neighboring arteries, SSD images were significantly superior to those of rotational DSA. For evaluation of the relationship to neighboring arteries, MIP images were significantly superior to those of rotational DSA. CONCLUSION: Three-dimensional DSA, especially SSD, provided more detailed information for evaluating cerebral aneurysms than did standard 2D and rotational DSA.  相似文献   
97.
Interobserver variation in diagnosis of dementia by brain perfusion SPECT   总被引:3,自引:0,他引:3  
Brain perfusion SPECT (BP-SPECT) has characteristic patterns of abnormality, enabling the differential diagnosis of dementia. The purpose of this study was to measure interobserver variations in the diagnosis of dementia using BP-SPECT. BP-SPECT images of 57 cases, 19 of Alzheimer's disease (AD), eight of multi-infarct dementia (MID), three of Pick's disease, five of other dementias, and 22 normal controls, were interpreted by ten nuclear medicine physicians with varying levels of experience. Brain MR images of the cases were then interpreted apart from SPECT. The physicians independently rated all of the diagnoses listed beforehand according to a five-point scale, with clinical information provided. Receiver-operating characteristic (ROC) curves and the area under the ROC curve (Az) were calculated. Az varied from 0.48 to 0.87. Mean Az's were significantly larger (p<0.05) in the diagnosis by SPECT than in that by MRI (0.715 and 0.629 for dementia vs. normal, 0.670 and 0.560 for AD or MID vs. normal, 0.610 and 0.416 for AD vs. normal, and 0.672 and 0.412 for AD vs. MID, respectively). Considerable interobserver variation was present in BP-SPECT interpretation. BP-SPECT may be more effective for the evaluation of dementia than MRI when the same nuclear medicine physicians interpret both images.  相似文献   
98.
Physical exercise stimulates cell proliferation in the adult dentate gyrus and facilitates acquisition and/or retention of hippocampal‐dependent tasks. It is established that regular physical exercise improves cognitive performance. However, it is unclear for how long these benefits last after its interruption. Independent groups of rats received both free access to either unlocked (EXE Treatment) or locked (No‐EXE Treatment) running wheels for 7 days, and daily injections of bromodeoxyuridine (BrdU) in the last 3 days. After a time delay period of either 1, 3, or 6 weeks without training, the animals were tested in the Morris water maze (MWM) either in a working memory task dependent on hippocampal function (MWM‐HD) or in a visible platform searching task, independent on hippocampal function (MWM‐NH). Data confirmed that exposure of rats to 7 days of spontaneous wheel running increases cell proliferation and neurogenesis. In contrast, neurogenesis was not accompanied by significant improvements of performance in the working memory version of the MWM. Longer time delays between the end of exercise and the beginning of cognitive training in the MWM resulted in lower cell survival; that is, the number of novel surviving mature neurons was decreased when this delay was 6 weeks as compared with when it was 1 week. In addition, data showed that while exposure to the MWM‐HD working memory task substantially increased survival of novel neurons, exposure to the MWM‐NH task did not, thus indicating that survival of novel dentate gyrus neurons depends on the engagement of this brain region in performance of cognitive tasks. © 2015 Wiley Periodicals, Inc.  相似文献   
99.
100.
A 78-year-old man was referred to our hospital for asymptomatic gross hematuria on April 16, 2007. Cystoscopy and abdominal computed tomography revealed a nonpapillary tumor at the upper area of the bladder. Abdominal and thoracic computed tomography showed no lymph nodes and no metastasis to other organs. Transurethral resection of bladder tumor (TURBT) was performed, and a pathological diagnosis of small cell carcinoma of the bladder at stage pT2N0M0 was made. Considering the patient's age and the location of the tumor, we administered chemotherapy using carboplatin and etoposide after resection of the tumor. After 2 courses of chemotherapy, a second-look TURBT was performed, and pathological examination showed no viable tumor cells. Cystoscopy performed after 3 months revealed recurrence of a nonpapillary tumor at a different area of the bladder. We performed TURBT and made a pathological diagnosis of small cell carcinoma of the bladder at stage pT1N0M0. The patient was free from disease in January 2011.  相似文献   
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