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41.
A M Glasgow J Weissberg-Benchell W D Tynan S F Epstein C Driscoll J Turek E Beliveau 《Pediatrics》1991,88(1):98-104
The characteristics of children with diabetes readmitted to Children's Hospital during a 5-year period, 1984 to 1989, were compared with those characteristics of new-onset patients admitted for stabilization and education and to outpatients in the Children's Hospital diabetes program to determine which characteristics were associated with patients who were readmitted. Changes in the frequency of readmissions were examined to determine whether the introduction of a diabetes team and a program that emphasizes the importance of ensuring that patients at risk of readmission consistently received insulin injections resulted in a reduction of readmissions. Readmissions occurred more frequently in patients who were black (71% compared with 38% of new-onset patients and 31% of outpatients) (P less than .001), from one-parent homes (56% compared with 27% of new-onset patients and 24% of outpatients) (P less than .001), and without third-party insurance (45% compared with 18% of new-onset patients and 15% of outpatients) (P less than .001). Readmissions were very common at 14 to 15 years of age (39% of readmissions vs 18% of outpatients) and very uncommon in children younger than age 9 (6% of readmissions vs 27% of outpatients) (P less than .001). Fewer readmissions for ketoacidosis occurred in the summer than in any other season (P less than .05). Readmissions fell by 47% over the 5-year period while new-onset patients increased by 85%. The reduction in frequency of readmissions was due to fewer readmissions for ketoacidosis and fewer readmissions in blacks, in patients from one-parent homes, and in patients without third-party insurance.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
42.
A theoretical algorithm for shaping the signal response during the approach to steady state in three-dimensional magnetization-prepared rapid gradient-echo (3D MP-RAGE) pulse sequences has been developed and implemented. This algorithm derives the flip angle series required to produce specifically chosen time evolutions of the signal intensities during the data acquisition segment of 3D MP-RAGE sequences. Theoretical predictions for the cases of unshaped, uniform, and mono-exponential decay signal responses were quantitatively validated with a doped-water phantom on a 1.5-T whole-body imager and in all cases there was excellent agreement between the theoretical and experimental values. The effects of RF inhomogeneities and eddy currents on the signal response shaping were also investigated. To demonstrate the potential utility of the technique, the signal response shaping algorithm was applied to a T1-weighted 3D MP-RAGE sequence to derive the acquisition flip angle series which theoretically yields the maximum white matter/gray matter signal difference (WGSD) consistent with the chosen response shape. Images obtained from a healthy volunteer using this variable flip angle sequence were compared with 3D RF-spoiled steady-state gradient-echo images obtained in the same total imaging time. The 3D MP-RAGE images demonstrated a 41% increase in the WGSD-to-noise ratio. These initial very promising results indicate that with further refinement to eliminate some intensity artifacts, the variable flip angle 3D MP-RAGE technique may, with respect to certain image properties, provide considerable improvements over currently available 3D gradient-echo imaging techniques. 相似文献
43.
Upon stimulation of Leydig cells with luteinizing hormone (LH) or dibutyryl-3',5'-cyclic AMP (Bt2cAMP) at 37 degrees C, two mitochondrial phosphoproteins accumulate with the same stimulant dose response as the increased rate of testosterone synthesis. The proteins pp32 and pp30 have apparent isoelectric points of 6.6 and 6.5 and molecular weights of approximately 32 30 kDa respectively, as determined by two-dimensional polyacrylamide gel electrophoresis. These two phosphoproteins are not detected in mouse adipose or liver cells nor in the total testicular cell population, of which Leydig cells constitute a small percentage. However, both proteins are also observed in mouse adrenal cells stimulated by ACTH or Bt2cAMP. The appearance of pp32 and pp30 is prevented by inhibitors of cytosolic protein translation, indicating that only newly synthesized protein is available as a substrate for phosphorylation. Proteolytic peptide mapping indicates that both of these mouse Leydig and adrenal proteins have structural similarity to pp30 (formerly denoted as ib), the 30 kDa mitochondrial phosphoprotein that we have observed previously in peptide hormone or Bt2cAMP-stimulated rat adrenal cortex (Pon, L.A., Hartigan, J.A. and Orme-Johnson, N.R. (1986) J. Biol. Chem. 261, 13309-13316; Alberta, J.A., Epstein, L.F., Pon, L.A. and Orme-Johnson, N.R. (1989) J. Biol. Chem. 264, 2368-2372) and rat corpus luteum cells (Pon, L.A. and Orme-Johnson, N.R. (1986) J. Biol. Chem. 261, 6694-6599). Since pp32 is a larger mitochondrial protein of similar primary structure to pp30, it is a potential precursor of this protein. Finally, the detection of the mitochondrial phosphoprotein pp30 in a third steroidogenic tissue type and a third species provides further correlative evidence that the production of pp30 may be an integral part of the subcellular mechanism by which peptide hormones stimulate steroid hormone biosynthesis. 相似文献
44.
Tatjana Pekmezovi? Natasa Ivanovi? Marina Svetel Dragana Nali? Tatjana Smiljkovi? Ranko Raicevi? Vladimir S Kosti? 《Movement disorders》2003,18(11):1389-1392
The aim of this cross-sectional study was to estimate the prevalence of different subtypes of idiopathic focal dystonia in the population of Belgrade (Serbia), Yugoslavia. On December 31, 2001, the crude prevalence of all studied types of dystonia (focal, segmental, and multifocal) in Belgrade was 13.6 per 100,000 population (11.8 per 100,000 for men and 15.2 per 100,000 for women). Type-specific prevalence for focal dystonia was 11.2 per 100,000. The prevalence for cervical dystonia, blepharospasm, writer's cramp and laryngeal dystonia were 5.9 per 100,000, 1.9 per 100,000, 1.9 per 100,000, and 1.1 per 100,000, respectively. 相似文献
45.
Douglas M. Howarth Martin T. Epstein Paul A. Thomas Leonard W. Allen Rachel Akerman Linda Lan 《European journal of nuclear medicine and molecular imaging》1997,24(12):1465-1469
The efficacy of fractionated out-patient radioiodine therapy in 38 patients with compressive symptoms due to long-standing
large multinodular goitres was assessed. The diagnosis was established by clinical assessment in addition to technetium-99m
pertechnetate thyroid scan or computed tomography scan of the thyroid and mediastinum. Oral iodine-131 therapy was administered
as a 2.22 GBq (60 mCi) cumulative dose over 4 months (555 MBq per month). All patients were monitored with serum thyroid-stimulating
hormone and free thyroxine (± free tri-iodothyronine) assays before the treatment and after each dose fraction. Clinical and
biochemical follow-up was performed on all patients and ranged from 6 to 45 months after therapy. The patients consisted of
35 female and three male patients with a median age of 59 years (range 37–87 years). Prior to treatment 20 patients were biochemically
hyperthyroid and 18 were euthyroid. Overall, 71% of patients reported a subjective improvement in compressive symptoms and
29% reported no change. Clinically assessed reduction in goitre size occurred in 92% of patients while there was no change
in 8%. At 3 months of follow-up, 31% of patients had become hypothyroid and at 18 months 66% were hypothyroid. Seven hyperthyroid
patients (35%) became euthyroid and 13 hyperthyroid patients (65%) became hypothyroid. Three patients who became hypothyroid
experienced neck soreness (transient in one patient, persistent in two patients). There were no differences in outcome between
patients who were hyperthyroid and those who were euthyroid prior to treatment. Fractionated out-patient radioiodine therapy
showed excellent short- and medium-term safety, was very well tolerated and offered a satisfactory alternative treatment to
surgery.
Received 23 May and in revised form 11 August 1997 相似文献
46.
A Rahmouni A Yang C M Tempany T Frenkel J Epstein P Walsh P K Leichner C Ricci E Zerhouni 《Journal of computer assisted tomography》1992,16(6):935-940
More accurate noninvasive estimation of prostate size is important in therapeutic trials for benign prostatic hyperplasia. The accuracy of MRI and transrectal ultrasound (TRUS) in assessing prostate weight was evaluated in 48 patients who underwent radical prostatectomy for stage A or B cancer. The volume derived from the wet weight of the freshly excised specimen was used as a reference. We compared that volume with volume estimates derived from the three-axis linear dimension measurement by MRI and TRUS using a tissue density of 1.05 g/cc and the standard formula for an ellipsoid object. Prostate and seminal vesicle volumes were also computed by contouring T2-weighted 5 mm thick contiguous MR images using a semiautomatic edge detection program and pixel summation. Three-axis volume MRI method versus volume from wet weight has slightly less scatter than TRUS three-axis method (r = 0.85 vs r = 0.81). Contoured MR volume method has the least scatter r = 0.93, statistically better than the linear axis method. Contoured MRI volumetric analysis appears superior to linear MRI or TRUS methods in estimating true prostate volume. 相似文献
47.
48.
Mikhail Strokin Marina Sergeeva Georg Reiser 《International journal of developmental neuroscience》2004,22(7):551-557
Various diseases of the central nervous system are characterized by induction of inflammatory events, which involve formation of prostaglandins. Production of prostaglandins is regulated by activity of phospholipases A(2) and cyclooxygenases. These enzymes release the prostaglandin precursor, the n-6 polyunsaturated fatty acid, arachidonic acid and oxidize it into prostaglandin H(2). Docosahexaenoic acid, which belongs to the n-3 class of polyunsaturated fatty acids, was shown to reduce production of prostaglandins after in vivo and in vitro administration. Nevertheless, the fact that in brain tissue cellular phospholipids naturally have a uniquely high content of docosahexaenoic acid was ignored so far in studies of prostaglandin formation in brain tissue. We consider the following possibilities: docosahexaenoic acid might attenuate production of prostaglandins by direct inhibition of cyclooxygenases. Such inhibition was found with the isolated enzyme. Another possibility, which has been already shown is reduction of expression of inducible cyclooxygenase-2. Additionally, we propose that docosahexaenoic acid could influence intracellular Ca(2+) signaling, which results in changes of activity of Ca(2+)-dependent phospholipase A(2), hence reducing the amount of arachidonic acid available for prostaglandin production. Astrocytes, the main type of glial cells in the brain control the release of arachidonic acid, docosahexaenoic acid and the formation of prostaglandins. Our recently obtained data revealed that the release of arachidonic and docosahexaenoic acids in astrocytes is controlled by different isoforms of phospholipase A(2), i.e. Ca(2+)-dependent phospholipase A(2) and Ca(2+)-independent phospholipase A(2), respectively. Moreover, the release of arachidonic and docosahexaenoic acids is differently regulated through Ca(2+)- and cAMP-dependent signal transduction pathways. Based on analysis of the current literature and our own data we put forward the hypothesis that Ca(2+)-independent phospholipase A(2) and docosahexaenoic acid are promising targets for treatment of inflammatory related disorders in brain. We suggest that Ca(2+)-independent phospholipase A(2) and docosahexaenoic acid might be crucially involved in brain-specific regulation of prostaglandins. 相似文献
49.
A 36-year-old woman with newly diagnosed acne rosacea is presented. Her skin changes were noticeable only under closest scrutiny, but she quit her job, became despondent about her acne, and developed suicidal ideation. The diagnosis and treatment of this patient allow a broader discussion of the somatically focused patient whose ideation reaches delusional intensity. 相似文献
50.
G Waterman J D Epstein N A Fenske 《Cutis; cutaneous medicine for the practitioner》1989,43(3):262-263
In most cases, herpes zoster (shingles) infections are benign and self-limited, requiring no treatment. However, if patients are elderly or immuno-compromised, they are at increased risk of complications such as visceral dissemination, cranial and nerve palsies, ophthalmic zoster, and postherpetic neuralgia. We present a case of herpes zoster infection complicated by both motor and sensory involvement in an elderly man. 相似文献