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91.
A [125I]cholecystokinin (CCK) analog and [125I]peptide YY (PYY) were used to localize and characterize CCK and neuropeptide Y (NPY) receptor binding sites in the rabbit vagal afferent (nodose) ganglion. High concentrations of CCK and NPY binding sites were observed in 10.6% and 9.2% of the nodose ganglion neurons, respectively. Pharmacological experiments using CCK or NPY analogs suggest that both subtypes of CCK (CCK-A and CCK-B) and NPY (Y1 and Y2) receptor binding sites are expressed by discrete populations of neurons in the nodose ganglion. These results suggest sites at which CCK or NPY, released in either the nucleus of the solitary tract or a peripheral tissue, may modulate the release of neurotransmitters from a select population of visceral primary afferent neurons. Possible functions mediated by these receptors include modulation of satiety, opiate analgesia, and the development of morphine tolerance.  相似文献   
92.
Combined high grade sarcoma and serous ovarian neoplasm.   总被引:1,自引:0,他引:1       下载免费PDF全文
A case of an ovarian serous epithelial neoplasm of borderline type admixed with sarcomatous elements is reported. This combination seems to be extremely rare with only four cases previously reported. It may represent a type of collision tumour or the development of a sarcoma in a growth with borderline differentiation.  相似文献   
93.
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   
94.
The relationship of perceived control over daily uplifts and hassles to depression and restraint was examined in a sample of 140 middle-class sixth graders. Results indicated that greater control over uplifts was associated with better functioning and lower control over hassles with poorer functioning, even after partialing out the respective number of uplifts and hassles reported. Moreover, when directly compared, control over uplifts showed more powerful associations with adaptational outcomes than did control over hassles. In a separate analysis, the number of uplifts over which children reported high control showed opposite relationships to adaptational outcomes than did the number of uplifts over which children reported low control. A different pattern appeared for hassles. Although the number of hassles with low control was associated with poorer functioning, the number of hassles over which children had high control was unrelated to adaptational outcomes. The possibility that control operates somewhat differently for positive and negative events is discussed.This research was supported by a grant to the second author from the Stanford Center for the Study of Families, Children and Youth. The authors are grateful to Rachelle Hacket for data analysis, Tom Gehring for data collection, and Susan Nolen-Hoeksema for critical comments.  相似文献   
95.
96.
A phase II trial of fludarabine phosphate using a bolus and continuous infusion regimen in previously treated multiple myeloma was performed. No responses were observed in eleven patients. There was no significant non-hematologic toxicity noted. Fludarabine phosphate is inactive in multiple myeloma using this schedule.  相似文献   
97.
Summary After orthotopic rat liver transplantation in the fully allogeneic BN (RT-1n) to LEW (RT-11) combination, the phenomenon of spontaneous tolerance of donor antigen occurs. We demonstrate two different immune mechanisms that may account for this process. Using adoptive transfer assays we show the presence of donor-specific T-suppressor lymphocytes in the spleens of long-term surviving liver graft, recipients. These cells prolong - adoptively transferred into irradiated syngeneic hosts — the survival of donor-specific (BN) but not third-party (DA) renal allografts (I00 days vs 1I days in control groups). Secondly, we demonstrate the replacement of Kupffer cells in the graft by recipient macrophages using polymorphic monoclonal antibodies in an immunoperoxidase technique. This may contribute to graft adaptation and thus to long-term graft acceptance.  相似文献   
98.
The effect of dietary zinc deficiency on patterns of phosphorylation and dephosphorylation of rat erythrocyte membrane proteins and erythrocyte filterability was examined. Weanling male Wistar rats were fed an egg white-based diet containing less than 1.1 mg zinc/kg diet ad libitum for 3 wk. Control rats were either pair-fed or ad libitum-fed the basal diet supplemented with 100 mg zinc/kg diet. Net phosphorylation and dephosphorylation of erythrocyte membrane proteins were carried out by an in vitro assay utilizing [gamma-32P]ATP. The membrane proteins were subsequently separated by sodium dodecyl sulfate-polyacrylamide gel electrophoresis, and the 32P content of gel slices was counted by Cerenkov counting. Erythrocyte filterability was measured as the filtration time of suspensions of erythrocytes, both untreated and preincubated with diamide, under constant pressure. Erythrocyte ghosts from zinc-deficient rats demonstrated greater dephosphorylation of protein bands R1 plus R2 and R7 than pair-fed rats and greater net phosphorylation of band R2.2 than pair-fed or ad libitum-fed control rats (P less than 0.05). Erythrocytes from ad libitum-fed control rats showed significantly longer filtration times than those from zinc-deficient or pair-fed control rats. In conclusion, dietary zinc deficiency alters in vitro patterns of erythrocyte membrane protein phosphorylation and dephosphorylation, whereas the depression in food intake associated with the zinc deficiency increases erythrocyte filterability.  相似文献   
99.
100.
Functional anatomy and biomechanics of the meniscus   总被引:2,自引:0,他引:2  
The meniscus is no longer considered the evolutionary remnant in the knee joint.Rather, it is now well established as an important structure that is integral to the complex biomechanics and proper functioning of the knee. The medial and lateral menisci form two crescent-shaped wedges of fibrocartilage between the femoral condyles and tibial plateaus.The knee joint biomechanics are based on a complex interaction of these intra-articular structures. The functions ascribed to the menisci include load transmission, shock absorption, stability, proprioception, joint lubrication, and joint nutrition. Load transmission generally is accepted as one of its primary functions. The menisci transmit a portion of the axial forces across the knee joint by converting this load into “hoop stresses.” This is accomplished by their unique shape, composition, and anatomic attachments. The menisci are relatively mobile structures and their motion during knee flexion also is determined by their shape and soft tissue attachments/constraints. Preservation of the meniscal functions is essential, and the authors review the basic anatomic and biomechanical concepts necessary to understand techniques for repair and restoration of these functions.  相似文献   
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