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91.
Tooth pulp-driven (TPD) neurons are found in the oral area of the first somatosensory cortex (SI) and they have been classified into fast (F-) type, slow (S-) type and fast type accompanied by afterdischarges (Fa). Effects of morphine on single unit responses of the F- and S-type neurons to pulp stimulation were examined by recording the discharges from a single neuron using a microelectrode. Intraperitoneal administration of morphine at 1.5 mg/kg markedly suppressed the response of S-type TPD neurons that fire with a long latency. This effect was completely reversed by naloxone at 0.2 mg/kg. On the other hand, the discharges of F-type neurons that fire with a short latency were not affected by application of morphine at 3 mg/kg. These findings suggest that S-type neurons in SI are concerned with pain perception.  相似文献   
92.
The levels of several soluble cytokine receptors in body fluids of healthy individuals change with age. Clinical application of the measurement of the serum soluble interleukin‐1 receptor type I (sIL‐1RI) level depends critically on the samples used as the controls. At present, there is no information regarding the levels of serum sIL‐1RI in healthy subjects. The purpose of this study is to reveal the age‐related changes that occur in the serum sIL‐1RIlevels of healthy individuals. We determined the serum sIL‐1RI levels of healthy Japanese children using ELISA. The serum sIL‐1RI level of children (0–14 years) was significantly higher than that of adults (more than 15 years) (P=0.0138, n=90). Thus, it is recommended that when the serum sIL‐1RI level of patients is evaluated, it should be compared against age‐matched controls. J. Clin. Lab. Anal. 23:175–178, 2009. © 2009 Wiley‐Liss, Inc.  相似文献   
93.
94.
CYP3A7 is a member of the human CYP3A family and a major form of P450 expressed in human fetal livers. Although CYP3A7 shares nearly 90% base sequence with CYP3A4, CYP3A7 shows striking functional differences in the catalytic preference for several substrates, such as dehydroepiandrosterone (DHEA) or dehydroepiandrosterone 3-sulfate (DHEA-3S). First, to clarify the reason for the differences between CYP3A7 and CYP3A4, a homology model of CYP3A7 was constructed using the CYP3A4 crystal structure. Because these two structures were similar, four kinds of chimeric enzymes were constructed to determine which sequences are important for exhibiting the characteristics of CYP3A7. The results of kinetic analysis of DHEA and DHEA-3S 16alpha-hydroxylations by CYP3A7, CYP3A4, and CYP3A chimeras suggested that the amino acid residues from Leu(210) to Glu(279) were important to express the specificity for substrates as CYP3A7. This region was on the F and G helices of the modeled CYP3A7. Furthermore, to assess which amino acid in this sequence is important for the substrate specificity of CYP3A7, a one-point mutation of CYP3A7 to CYP3A4 was made by site-directed mutagenesis. The mutants of K224T and K244E had lost DHEA and DHEA-3S 16alpha-hydroxylation activities. The mutants also greatly decreased the metabolism of testosterone, erythromycin, nevirapine, and triazolam relative to those activities of CYP3A7 wild-type enzyme. From these results, it is expected that CYP3A7 can recognize specific substrates using the lysines in F-G loops.  相似文献   
95.
The hypercoagulable state in patients with toxemia of pregnancy was investigated in comparison with normal pregnant women using new coagulation parameters, mainly thrombin-antithrombin III (TAT) complexes, alpha 2-antiplasmin-plasmin complexes (PIP), and D-dimer FDP. When the patients were categorized by the classification of the WHO Study Group (1985), significant increases of TAT complexes and alpha 2-PIP complexes with decreases of the ATIII level were observed in the groups with preeclampsia and severe gestational hypertensive disease as compared to normal pregnant women. A significant increase of D-dimer FDP was observed in a group with severe gestational hypertensive disease. Additionally, the relationship between clinical signs and the hypercoagulable state in the patients was analyzed using canonical correlation analysis as a multivariate analysis. The clinical signs and coagulation parameters had a significantly high correlation of lambda 1 = 0.7219, p less than 0.01. The results showed that clinical signs were associated with simultaneous coagulation abnormalities. The indices obtained from the results of canonical correlation analysis, which were called the clinical index and the coagulation index, should be useful in evaluating the efficacy of anticoagulation therapy.  相似文献   
96.
Experiments were conducted to determine whether neutron-induced genetic damage in parental germline cells can lead to the development of cancer in the offspring. Seven-week-old C3H male mice were irradiated with 252Cf neutrons at a dose of 0, 50, 100, or 200 cGy. Two weeks or 3 months after irradiation, the male mice were mated with virgin 9-week-old C57BL females. Two weeks after irradiation, the irradiated male mice showed an increased incidence of sperm abnormalities, which led to embryo lethalities in a dose-dependent manner when they were mated with unirradiated female mice. Furthermore, liver tumors in male offspring of male mice in the 50 cGy group were significantly increased in 19 of 44 (43.2%) animals, in clear contrast to the unirradiated group (1 of 31; 3.2%) ( P < 0.01). In the 100 cGy group, 6 of 39 (15%) mice had lesions. At 3 months after irradiation abnormal sperm and embryonal lethality were not significantly increased. The incidences of liver tumors in male offspring from the 50 cGy, 100 cGy and 200 cGy groups were 6 of 20 (30%), 5 of 22 (23%) and 1 of 19 (5%), respectively, which are not significantly increased compared with the control. It is concluded that increased hepatic tumor risk in the F1 generation may be caused by genetic transmission of hepatoma-associated trait(s) induced by 252Cf neutron irradiation.  相似文献   
97.
We report on a unique posterior approach for bilateral nephrectomy by retroperitoneoscopy that was conducted in a 13-year-old boy with end-stage renal disease managed by peritoneal dialysis. A posterior approach for bilateral nephrectomy by retroperitoneal laparoscopy provided adequate visualization and created enough working space for the manipulation. The procedure was performed during a short period, and the patient did not need to be repositioned. Retroperitoneal laparoscopic bilateral nephrectomy is a useful option in school-aged children with poorly functioning kidneys, particularly those children also undergoing peritoneal dialysis.  相似文献   
98.
PURPOSE: We report our experience with laparoscopic adrenalectomy in nine patients with pheochromocytoma and compare the morbidity with that of laparoscopic adrenalectomy for tumors of other pathology. PATIENTS AND METHODS: Between January 1997 and November 1999, nine patients underwent laparoscopic surgery for pheochromocytoma via a transperitoneal approach. Of the patients, eight had solitary tumors, and one presented with bilateral pheochromocytomas. The mean size of the tumors was 5.4 cm. The surgical outcomes of the 9 patients were compared with those of 28 patients with adrenal tumors of other pathology (primary aldosteronism in 15 patients, Cushing syndrome in 6, and nonfunctioning adenoma in 7) who underwent transperitoneal laparoscopic adrenalectomy during the same period. The mean size of the adrenal tumors of other pathology was 2.4 cm. RESULTS: In eight of the nine patients with pheochromocytoma, laparoscopic adrenalectomy was successful. The procedure was converted to open surgery in the patient with bilateral tumors because of uncontrollable hemorrhage. A hypertensive crisis with the systolic blood pressure >200 mm Hg occurred in 6 patients (67%), but the episode could be controlled by temporary discontinuation of tumor manipulation, administration of drugs, or both. In adrenalectomy for pheochromocytoma, the mean operative time was longer (199 v 177 minutes) and the mean estimated blood loss was greater (360 v 54 mL) than for tumors of other pathology. Blood transfusion was given to two patients with pheochromocytoma but to no patient with tumors of other pathology. The patients with adrenal tumors of other pathology could resume normal activity earlier (mean 18 v 26 days) than those with pheochromocytoma. CONCLUSION: The operation is more difficult and the morbidity is higher in laparoscopic adrenalectomy for pheochromocytoma than that for tumors of other pathology. An experienced team of surgeons with advanced laparoscopic skills and anesthesiologists is mandatory. In large tumors, great caution should be taken for intraoperative complications. Nevertheless, laparoscopic adrenalectomy is not contraindicated for pheochromocytoma and can be performed safely.  相似文献   
99.
100.
PURPOSE: The purpose of this study was to investigate the behavior of the photopic negative response(PhNR) of cone-induced electroretinogram (cone ERG) in patients with normal-tension glaucoma (NTG). METHODS: Cone ERGs were recorded from 30 eyes of 30 patients with NTG according to the recording conditions of the International Society for Clinical Electrophysiology of Vision protocol which is now widely used in clinics. The amplitudes and implicit times of the PhNRs were measured and compared with normal controls. I further attempted to find a correlation between the PhNR amplitude loss and the cupping/disc ratio representing a loss of the nerve fiber layer and severity of visual field defbct. RESULTS: The PhNR amplitudes recorded from patients with NTG were significantly reduced compared with those from normal subjects (p < 0.05). However, the PhNR amplitude loss did not correlate with the cupping/disc ratio or the severity of visual field defect. CONCLUSIONS: The Results suggested that the PhNR amplitude qualitatively reflected ganglion cell loss in patients with NTG even under recording conditions which are widely used in the clinical field.  相似文献   
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