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41.
The bioequivalence of recombinant human growth hormone (rhGH) (somatropin) and its N-methionyl variant (Met-hGH) [Protropin((R)) (somatrem for injection)] was determined in 42 healthy male volunteers (n = 21 per treatment) who were randomized to receive either protein by subcutaneous administration of 0.1 mg kg(minus sign1). Serum samples were collected over 24 h after the injection, and the concentration of human growth hormone (hGH) were determined by an immunoradiometric assay. Bioequivalence of the two proteins was assessed by determining whether the 90% confidence limits for the ratio of geometric means using logarithmically transformed AUC and C(max) parameters (log(10)AUC(0--24), log(10)AUC(0--infty infinity), and log(10)C(max)) were within the 80--125% range. The bioequivalence of the two treatments was also tested by calculating a bioequivalance index (xi(2)) that measured the difference between the two mean concentration-time profiles. The 90% confidence intervals for the ratios of the geometric means for AUC were within the prescribed 80--125% range for bioequivalence. The upper limit of the 90% confidence interval for the ratio of the geometric means for C(max) fell slightly outside the 125% criterion even though the geometric mean itself, 106.6%, was very close to the ideal of 100%. There was a larger standard error associated with C(max) than with the AUCs, and this marginally larger confidence limit for C(max) resulted more from the variance among the subject than to the difference in the means. In fact, the bioequivalence index, xi(2), was 0.075, indicating that the mean curves after rhGH and Met-hGH are essentially superimposable.  相似文献   
42.
Experimental research has recently shown that acupuncture induces the formation of o-pioid-like peptides in animals.The role ofβ-endorphin in the mechanism of acupuncture is discussed:some authors maintain the hormonal hypothesis,others the role of neurotransmltters and,up to thepresent,no convincing evidence for either hypothesis has been demonstrated.In order to provide fur-ther evidence,we tested the β-endorphin levels and other parameters(VLP,lymphocyte subsets,NKcells and phagocyte activity of monocytes)in a group of 90 patients suffering from various painful dis-orders treated with acupuncture.Zusanli(ST 36)and Hegu(LI 4)acupoints were selected.A homo-geneous group of 30 subjects was used as control.Evaluation of the above parameters was made with3 series of blood tests;before treatment,30 minutes and 24 hours after acupuncture treatment.In theacupuncture group,the following results were achieved: a)A considerable increase in β-endorphin levels,which remained high even 24 hours afteracup  相似文献   
43.
Resting energy expenditure (REE) was measured by indirect calorimetry and body composition was assessed by both direct (bioimpedance) and indirect (anthropometry) methods in 20 hospitalized patients with biopsy-proven ileal Crohn's disease and in a group of 16 healthy volunteers matched for sex, age, and height with the patient group. The Crohn's disease activity index was below 120 in all patients studied. who were treated with a low dose of corticosteroids (0.2–0.3 mg/kg body wt of prednisone). The average weight of Crohn's patients was signficantly lower than that of controls (55.70 vs 70.50 kg,P<0.001) due to both lower fat mass (9.97 vs 18.30 kg,P<0.001) and lower lean body mass (45.72 vs 52.20 kg,P<0.02). The average REE was significantly higher in the control group (1785.42±7.503 vs 1559.1±48.39 kcal/day,P<0.001). However, these differences disappeared when REE was normalized by lean body mass (LBM) (34.49±2.56 vs 34.704±3.75 kcal/kg LBMP=NS). The nonprotein respiratory quotient was significantly lower in the patient group (0.823±0.031 vs 0.882±0.012.P<0.025), indicating an increased lipid oxidation. This increased lipid oxidation might explain the reduced fat stores found in the group of Crohn's patients, suggesting also that a sufficiently lipid-rich diet could be useful in their nutritional management.  相似文献   
44.
Primary olfactory neurons located in the olfactory neuroepithelium project to the ipsilateral olfactory bulb and undergo a continuous process of neurogenesis and differentiation. We describe, in the adult rat, the kinetics of proliferation, differentiation and survival of primary olfactory neurons either in the presence or absence of their target, the olfactory bulb. The experimental design included unilateral bulbectomy, coupled with a single bromodeoxyuridine pulse 35 days after surgery. The rate of proliferation and survival of olfactory neurons was then examined by immunohistochemistry for bromodeoxyuridine, and the differentiation status by in situ hybridization for calmodulin messenger RNA in immature and mature olfactory neurons and immunohistochemistry for the dipeptide carnosine in mature olfactory neurons. We show that primary olfactory neurons can synthesize carnosine in the absence of the olfactory bulb. However, the number of carnosine-immunopositive neurons in the absence of their target is dramatically reduced to less than one-fourth, whereas the number of olfactory neurons expressing calmodulin messenger RNA is only slightly reduced. The numeric reduction of camosine-positive neurons in the target-deprived neuroepithelium is correlated with a dramatic reduction in the survival rate of olfactory neurons, since newly generated olfactory neurons are completely lost 35 days after the bromodeoxyuridine pulse. In contrast, in the normal olfactory neuroepithelium almost one-third of newly generated olfactory neurons survive 35 days after the bromodeoxyuridine pulse. On the whole, these data indicate that most of the primary olfactory neurons have a short lifespan but that once they have connected with the olfactory bulb they may persist longer, and suggest that throughout adulthood olfactory neurons are overproduced, differentiate independently from their target, and then undergo a process of target-induced neuronal selection.  相似文献   
45.
To perform a breast reduction under local anesthesia we need a large amount of anesthetic with lasting effects. For this I use a solution of 25 cc of lidocaine, 25 cc of bupivacaine, and 1 cc of epinephrine in 350 cc of saline solution. The bupivacaine allows a 4–6-hour operation. Once the breast is infiltrated, a great amount of anesthetic is lost in the incision, in the dissection, and in the resected tissue. Thus, a low dose remains subcutaneously to be metabolized by the liver. The serum lidocaine levels are low during these operations, as demonstrated by fluorescence polarization immunoassay. Under analgesic sedation the submammary sulcus and the retroglandular space are infiltrated, blocking the perforants of the intercostal nerves, under the areola, beneath the skin where the incision is made and where the aerola is placed. This procedure has been applied to many techniques of breast reduction by modifying the infiltration under the incision lines. For hypertrophy up to 1000 g, 200–300 cc of anesthetic solution is used for both breasts at one stage, while for gigantomastia, about 400 cc of anesthetic is used, infiltrating and reducing one after the other. As the blood loss is minimal and the recovery very fast, with an appropriate adhesive bandage and a soutien, the patient could be discharged in the afternoon. Our experience includes 94 reduction mastoplasties with local anesthesia, and also 74 other mastoplasties with equally good results. There were no patient complaints and, in general, they felt very comfortable, awakening without pain or side effects.  相似文献   
46.
Summary We report 48 patients operated on for lumbar disc herniation in the second decade of life (aged 13–20 years) in our Neurosurgical Division. To analyze the clinical and diagnostic features and surgical outcome of the disease in teenagers and to point out any differences from adults, we made a detailed study of over 900 juvenile cases and compared them with 11000 adult cases reported in the literature. Low-back pain proved to be less frequent among youngsters both as a first symptom and at diagnosis, while sensorimotor deficits have the same frequency in the two age groups. Herniation occurs more often at L4–L5 and is more frequently median among teenagers. The long-term surgical results in children and adolescents are better than in adults.  相似文献   
47.
Exostoses of the external auditory canal can occur in patients living in coastal, southern California communities with a history of cold-water aquatic activities such as ocean surfing and swimming. Although most canal exostoses are asymptomatic, patients with canal obstruction greater than 80% can have recurrent episodes of external otitis and a related conductive hearing loss. In most cases, medical treatment resolves the symptomatic external otitis and related hearing loss. Patients recalcitrant to medical treatment are candidates for surgical removal of the exostoses. This report reviews the authors' surgical experience with 18 patients (27 ears) who have undergone surgical removal of exostoses. Their preferred surgical technique of transmeatal removal of exostoses with a specialized mallet and thin chisel under local anesthesia is described.  相似文献   
48.
Cell kinetics parameters have been analysed in colonic mucosa at different distances from a tumour in patients with colon carcinoma. Total cell number (TCN), H thymidine labelling index (TLI), mitotic index (MI), Goblet cell index (GCI) and the distribution of labelled cells along the crypt column (cell position frequency plot) were determined in well-aligned crypts. Total cell number, GCI and the labelled cell position frequency plots were similar in different samples from the same individual. A negative linear correlation between TCN and TLI was observed. The analysis of the cell position plots showed two patterns 1) with a high concentration in the bottom fifth of the crypt and 2) with frequent labelled cells at high positions. Whereas a negative correlation between overall TLI and the percent contribution to the TLI of the lowermost fifth was seen, the correlation was positive for the next 3 fifths and labelling was absent in the last part of the crypt.  相似文献   
49.
Ethinylestradiol (EE) induces cholestasis by affecting bile salt-dependent and -independent fractions of the bile flow. The decrease in bile salt-independent flow is thought to be due, in part, to a reduction in the expression of the canalicular transporter Mrp2. The impact of modulation of Mrp2 function by sodium ursodeoxycholate (UDC) in EE cholestasis is unknown. We evaluated the protective effect of UDC on EE-induced impairment of Mrp2 activity in vivo and in isolated hepatocytes, by using the substrate dinitrophenyl S-glutathione (DNP-SG). EE was administered to male Wistar rats at a dose of 5 mg/kg s.c. for 5 days. UDC was coadministered with EE at a dose of 25 mg/kg b.wt. i.p. for the same period. EE alone reduced DNP-SG biliary excretion by 55% when compared with controls. Coadministration with UDC partially restored the alteration. Secretion rate of DNP-SG was decreased by 30% in isolated hepatocytes from EE-treated rats, but, contrary to in vivo results, UDC coadministration did not restore DNP-SG transport, likely as a consequence of bile salt washout resulting from the isolation procedure. As a confirmation, tauroursodeoxycholate hepatocyte preloading significantly increased Mrp2 activity. Western blotting analysis of Mrp2 indicated that EE administration significantly reduced its level in total and plasma membranes and that UDC coadministration failed to revert this alteration. In conclusion, UDC improvement in Mrp2 transport activity in vivo likely derived from a direct enhancement of Mrp2 function rather than from a restoration of its expression levels. This provides a novel mechanism explaining the beneficial effects of UDC in EE-induced cholestasis.  相似文献   
50.
Specialized DNA arrays for the differentiation of pancreatic tumors.   总被引:3,自引:0,他引:3  
PURPOSE: Malignant tumors of the pancreas are frequently indistinguishable from inflammatory tumors arising in the context of a chronic pancreatitis with the use of conventional imaging techniques. Thus, cytologic analysis of cells obtained by abdominal ultrasound, computed tomography, or endoscopic ultrasound-guided fine needle aspiration biopsy is required for diagnosis. However, the reliability of cytologic analyses of pancreatic fine needle aspirates remains unsatisfactory, with a diagnostic accuracy of < or =80%. The purpose of the current study was therefore to develop a novel diagnostic approach based on expression profiling of biopsy material using a specialized diagnostic cDNA array. EXPERIMENTAL DESIGN: Previous gene expression profiling studies were reevaluated to design a 558-feature diagnostic array. Minimal amounts of residual material from pancreatic cytology samples as well as surgically resected tumor and control tissue specimens were analyzed using the diagnostic array and a newly developed statistical classification system. RESULTS AND CONCLUSIONS: Our diagnostic approach resulted in 95% accurate differentiation between ductal adenocarcinomas and nonmalignant tumors of the pancreas. The diagnostic array, in conjunction with conventional diagnostic procedures, is thus suitable to significantly improve the reliability of pancreatic cancer diagnostics and can be expected to become a valuable new tool in the routine workup of suspect masses in the pancreas.  相似文献   
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