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1.
Y Sun A Hildesheim LA Brinton PC Nasca CL Trimble RJ Kurman RP Viscidi KV Shah 《Canadian Metallurgical Quarterly》1996,63(2):200-203
We describe a case of positional dyspnea due to compression of the tracheobronchial tree by an extensive thoracic aneurysm. In a 77-year-old woman with long-standing systemic hypertension, intermittent anterior chest pain gradually developed over several years. She had no history of asthma or thoracic trauma. She was admitted to our hospital because of sudden, severe shortness of breath. The breathlessness was markedly worse when she lay on her back or on her right side. On physical examination, she was in acute respiratory distress with cyanosis, severe hypertension (180/110 mmHg), tachycardia, and inspiratory stridor. A chest X-ray film showed loss of volume and nearly complete radiopacity of the left hemithorax. Arterial blood gas analysis revealed an arterial oxygen partial pressure of 54.8 mmHg, a carbon dioxide partial pressure of 39.8 mmHg, and an oxygen saturation of 84.5 percent on room air. Computed tomographic examination of the thorax showed dilation of the aortic arch and descending aorta, and marked compression of the trachea and the left main bronchus. Examination with a fiberoptic bronchoscope revealed extrinsic compression of the trachea just proximal to the carina. The patient's symptoms stabilized. However, she did not undergo surgery because of her age and because of the size of the aneurysm. She died due to rupture of the aneurysm. 相似文献
2.
KV Shah TD Kessis F Shah JW Gupta D Shibata RW Jones 《Canadian Metallurgical Quarterly》1996,15(2):127-130
Unstable expansion of the CTG repeats in the 3' untranslated region encoding a member of the protein kinase family in the q13.3 band on chromosome 19 is a mutation specific for myotonic dystrophy. To examine the correlation between clinical expression and CTG trinucleotide repeat length, we carried out Southern blot analysis in a family with myotonic dystrophy. In this pedigree, the expanded CTG repeats were transmitted maternally. The mother had three female children. The mother had about 200 CTG repeats, and the number of repeats for each child was about 800, 1500 and 1600 in birth order. The mother and the patient with 800 repeats were unaware of muscle weakness or myotonia. Symptoms were present from age 3 years in the patient with 1500 repeats and from birth in the one with 1600 repeats. Although the mother menstruated regularly, the patients with 800 and 1500 repeats both menstruated irregularly, and the one with 1600 repeats has never menstruated. The age of onset and severity of the disease were correlated with the size of the expanded repeats. Endocrinological studies revealed that the basal levels of the gonadotropins, PRL and E2 were within normal range, and a pituitary response to LHRH was observed. These data suggest that the amenorrhea and menstrual irregularities were caused by a suprahypophyseal dysfunction. When expanded CTG repeats are transmitted maternally, abnormal products resulting from the metabolic disturbance in the affected mother may harm the fetus in utero. A heterozygous fetus, who has more CTG repeats, may be unable to metabolize the pathologic products sufficiently and therefore may become more severely affected. This may explain the exclusive maternal transmission of congenital myotonic dystrophy. 相似文献
3.
Urinary protein and calcium excretion were assessed in 77 patients with the hepatic glycogen storage diseases (GSD): 30 with GSD-I (median age 12.4 years, range 3.2-32.9 years), 25 with GSD-III (median age 10.5 years, range 4.2-31.3 years) and 22 with GSD-IX (median age 11.8 years, range 1.2-35.4 years). Inulin (Cinulin) and para-aminohippuric acid (CPAH) clearances were also measured in 33 of these patients. Those with GSD-I had significantly greater albumin (F = 15.07, P < 0.001), retinol-binding protein (RBP) (F = 14.66, P < 0.001), N-acetyl-beta-D-glucosaminidase (NAG) (F = 9.41, P < 0.001) and calcium (F = 7.41, P = 0.001) excretion than those with GSD-III and GSD-IX. GSD-I patients (n = 18) also had significantly higher Cinulin (F = 5.57, P = 0.009), but CPAH did not differ (F = 0.77, NS). Renal function was normal in GSD-III and GSD-IX patients. In GSD-I, Cinulin (r = -0.51, P = 0.03) and NAG excretion (r = -0.40, P = 0.03) were inversely correlated with age, whereas albumin excretion was positively correlated with age (r = +0.41, P = 0.03). RBP and calcium excretion were generally high throughout all age groups. Hyperfiltration in GSD-I is associated with renal tubular proteinuria that occurs before the onset of significant albuminuria. Deficiency of glucose-6-phosphatase within the proximal renal tubule may primarily cause tubular dysfunction, glomerular hyperfiltration being a secondary phenomenon. 相似文献
4.
Precipitation of nickel ammonium sulphate achieved by mixing solutions of nickel sulphate and ammonium sulphate in a 5 1 MSMPR crystallizer is used to investigate both crystallization and agglomeration kinetics from the steady-state crystal size distribution. An iterative non-linear parameter estimation procedure is used to deduce the kinetic rate parameters in the solution of the agglomeration model suggested by Liao and Hulburt from the data-set obtained by size analysis of the product crystals. The results obtained are correlated in terms of conventional power law kinetic expressions. 相似文献
5.
Geometry-Dependent R-Curve for Quasi-Brittle Materials 总被引:4,自引:0,他引:4
Fracture of quasi-brittle materials such as ceramics and cement-based materials can be described by an R -curve, defined as fracture resistance. The R -curve can be constructed as the envelope of the strain energy release rates ( G ). In this study, R -curve is defined as an envelope of G -curves obtained by varying the dimensions of identical specimens, while keeping the geometry and the initial flaw size constant. By approximating the G -curve with a second-order function of the crack length, a simple formulation of the R -curve is derived by solving a differential equation. Three parameters are needed for the proposed R -curve. These parameters can be obtained by testing a notched-beam specimen and using linear elastic fracture mechanics. The proposed R -curve simulates well the geometry dependency as well as other characteristics of the fracture response of quasi-brittle materials. 相似文献
6.
Narendra Singh Shah & Nirankar Nath 《International Journal of Food Science & Technology》2006,41(9):1073-1081
Litchi (Litchi chinensis Sonn.) fruits are very susceptible to pericarp browning which adversely affects consumer acceptability even though the aril portion remains in excellent condition. Litchi arils (litchis) were treated with a solution containing 0–2% (w/v) calcium lactate (CL), 0–0.02% (w/v) 4‐hexyl resorcinol (4‐HR) and 1% potassium sorbate. The pH of solution was adjusted to 4.0 with citric acid. Treated litchis were packed in polystyrene trays, over‐wrapped with polypropylene film, vacuum‐packed (0, 47409.3, 94831.9 Pa) and stored at 4 ± 2 °C. Drip losses, pH, total soluble solids (TSS), sensory attributes and microbiological quality of stored samples were estimated. A four‐factor, three‐level experimental design (D6 Hokes design) with 19 experiments was chosen. Mathematical models were developed to analyse and predict the effect of CL, 4‐HR, in‐package vacuum and storage time on the responses. TSS, pH and sensory scores decreased significantly (P 0.01), whereas drip losses and microbial count increased significantly (P 0.01) with time. Drip loss was significantly (P 0.1) reduced by addition of CL. 4‐HR prevented browning and changes in colour score during storage were significantly less. Vacuum in packages exerted significant (P 0.01) effect over pH, TSS, sensory and microbiological qualities of minimally processed litchis. 相似文献
7.
8.
The unusual occurrence of plastic deformation in an adult is described. 相似文献
9.
Alan Royce Jiwaji Suryawanshi Udayan Shah Krishna Vishnupad 《Drug development and industrial pharmacy》1996,22(9):917-924
A melt granulation process has been investigated (1, 2) which efficiently agglomerates pharmaceutical powders for use in both immediate- and sustained-release solid dosage forms. The process utilizes materials that are effective as granulating fluids when they are in the molten state. Cooling of the agglomerated powders and the resultant solidification of the molten materials completes the granulation process. Both the molten agglomeration and cooling solidification were accomplished in a high shear Collette Gral mixer equipped with a jacketed bowl. Hence, the melt granulation process replaces the conventional granulation and drying operations which use water or alcohol solutions. The melt granulation process has been investigated using immediate- and sustained-release TAVIST® (clemastine fumarate USP) tablet formulations. The TAVIST granulations have been characterized by power consumption monitoring, measurement of the granulation particle size distribution, bulk and tapped density determinations, and loss-on-drying measurements. Scale-up of the melt granulation process for the sustained release TAVIST tablet formulation was judged successful based on a comparison of the hardness, friability, weight uniformity during compression, disintegration time, and dissolution rate data obtained at different manufacturing scales. 相似文献
10.
James Mammen Devavrat Shah 《IEEE transactions on information theory / Professional Technical Group on Information Theory》2007,53(3):1108-1116
Grossglauser and Tse (2001) introduced a mobile random network model where each node moves independently on a unit disk according to a stationary uniform distribution and showed that a throughput of Theta(1) is achievable. El Gamal, Mammen, Prabhakar, and Shah (2004) showed that the delay associated with this throughput scales as Theta(nlogn), when each node moves according to an independent random walk. In a later work, Diggavi, Grossglauser, and Tse (2002) considered a random network on a sphere with a restricted mobility model, where each node moves along a randomly chosen great circle on the unit sphere. They showed that even with this one-dimensional restriction on mobility, constant throughput scaling is achievable. Thus, this particular mobility restriction does not affect the throughput scaling. This raises the question whether this mobility restriction affects the delay scaling. This correspondence studies the delay scaling at Theta(1) throughput for a random network with restricted mobility. First, a variant of the scheme presented by Diggavi, Grossglauser, and Tse (2002) is presented and it is shown to achieve Theta(1) throughput using different (and perhaps simpler) techniques. The exact order of delay scaling for this scheme is determined, somewhat surprisingly, to be of Theta(nlogn), which is the same as that without the mobility restriction. Thus, this particular mobility restriction does not affect either the maximal throughput scaling or the corresponding delay scaling of the network. This happens because under this 1-D restriction, each node is in the proximity of every other node in essentially the same manner as without this restriction 相似文献