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11.
N. Glajchen S. Thomas P. Jowell S. Epstein M.D. F. Ismail M. Fallon 《Calcified tissue international》1990,46(1):28-32
Summary The paucity of information on the effect of long-term high-dose salmon calcitonin administration on normal bone mineral metabolism
and histology prompted an investigation of the influence of high-dose synthetic calcitonin in the rat. Serum ionized calcium,
osteocalcin or BGP (bone gla protein), and immunoreactive PTH were measured serially during calcitonin administration and
bone histomorphometry analyzed at 6 weeks (after sacrifice). Daily injections of salmon calcitonin, 0.4 IU/100 g (group B)
and 2 IU/100 g (group C), resulted in significant hypocalcemia at 4 hours for both experimental groups (P<0.004). Serium iPTH was significantly higher over the study period for both groups administered calcitonin. Serum BGP levels
were significantly lower than controls during the study in group C (P<0.002) and to a lesser extent in group B (P<0.05). In group C, bone histomorphometry revealed increased resorption (onteoclast count), decreased trabecular bone volume,
and decreased double-labeled tetracycline surface (bone formation). In group B an increase in osteoclast count but no alteration
in bone formation was observed. To assess the role of PTH in the above findings, high-dose calcitonin was administered to
parathyroidectomized rats. All of the above changes in bone histomorphometry were not observed in this group of animals. In
conclusion, high doses of calcitonin promote hypocalcemia, secondary hyperparathyroidism, and osteoclastosis in the normal
rat in a dose-dependent manner with very high-dose calcitonin impairing bone formation. 相似文献
12.
12-month outcome of patients with major depression and comorbid psychiatric or medical illness (compound depression) 总被引:1,自引:0,他引:1
G I Keitner C E Ryan I W Miller R Kohn N B Epstein 《The American journal of psychiatry》1991,148(3):345-350
OBJECTIVE: Inpatients with major depressive illness often have coexistent nonaffective psychiatric and/or medical conditions. The authors' objective is to address the following questions: 1) What is the effect of comorbid illness on the severity of major depression and associated psychosocial factors? 2) How does the course of depression differ for patients with and without concurrent illness? 3) Do patients with compound depression differ in rate of recovery and time to recovery from patients with pure depression? METHOD: The subjects were 78 patients with a DSM-III diagnosis of major depression who were consecutively admitted to an acute care university-affiliated psychiatric hospital; 37 of these patients had major depression only and 41 had major depression compounded by a coexisting axis I, II, or III condition. The patients were studied while hospitalized and for 12 months after hospital discharge. Instruments used included the Modified Hamilton Rating Scale for Depression, the Global Assessment Scale, and the Social Readjustment Rating Scale. RESULTS: Patients with compound depression reported significantly poorer functioning over the 12-month follow-up period and had lower recovery rates than the patients with pure depression. There were no differences in recovery rates between men and women with compound depression, but significantly more men than women with pure depression recovered. CONCLUSIONS: Compound depression is a common clinical occurrence, the course of illness is more difficult for patients with compound depression than for patients with pure depression, and the recovery rate of patients with compound depression is lower than that of patients with pure depression. 相似文献
13.
The effects of intramuscular injections of succinylcholine with or without atropine on heart rate and rhythm were studied in 50 unpremedicated children 6-18 months of age. All had anesthesia induced with N2O-O2 and halothane 2% by face mask. Sixty seconds later, one of four study drugs or drug combinations was injected into the deltoid muscle of patients in groups 1-4. Following injection, halothane concentration was reduced to 1%, and ventilation was controlled. Patients given atropine only (0.02 mg/kg), succinylcholine only (4 mg/kg), or a combination of both (4 mg/kg succinylcholine plus 0.02 mg/kg atropine) showed transient increases in heart rate to 106 +/- 7.5%, 113 +/- 11.8%, and 109 +/- 10.1% (mean +/- SD) of control, followed by a decrease to 78 +/- 6.7%, 79 +/- 9.4%, and 80 +/- 10.5%, respectively, in 2-3 min after injection. Patients given a combination of succinylcholine (4 mg/kg) plus a higher dose of atropine (0.03 mg/kg) also had a transient increase in heart rate to 107 +/- 7.5%, followed by a decrease to 82 +/- 11.8% 2 min after injection. However, this group differed from the other three groups in presenting a second, prolonged increase in heart rate to 115 +/- 9.0% of preinjection levels. Patients in group 5 (controls) received no injections. Their heart rate decreased to 76 +/- 10.78% of preinduction level within 90 sec of induction, and remained unchanged thereafter. We conclude that succinylcholine (4 mg/kg) can be used intramuscularly with or without atropine (0.02 mg/kg) in lightly anesthetized young children without producing severe bradycardia.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
14.
Immunosuppressed persons are at greater risk of developing malignancies. In human immunodeficiency virus (HIV) immunosuppression the most common oral cancers are Kaposi's sarcoma and non-Hodgkin's lymphoma. Squamous cell carcinoma has also been reported to be associated with HIV disease. Kaposi's sarcoma is the most frequent neoplastic disease in acquired immunodeficiency syndrome and is by far the most common in the head and neck area. This article reviews the prevalence, clinical features, and management of these diseases in HIV infection. 相似文献
15.
16.
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
17.
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
18.
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
19.
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
20.
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