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排序方式: 共有866条查询结果,搜索用时 31 毫秒
1.
The effects of hypothalamic hormones and electrolytic lesioning of the ventromedial hypothalamic nuclei (VMH) on histidyl-proline diketopiperazine (cyclo(His-Pro] binding in the rat liver were studied. VMH-lesioning markedly decreased cyclo(His-Pro) binding in the liver. Scatchard analysis revealed that the loss of cyclo(His-Pro) binding induced by VMH lesioning was due to a decrease in the number and affinity of binding sites. Somatostatin (SS) administration decreased cyclo(His-Pro) binding. The SS-induced changes in cyclo(His-Pro) binding were due to changes in the binding affinity. On the other hand, the administration of TRH or LH-RH did not affect cyclo(His-Pro) binding in the liver, although cyclo(His-Pro) has been proposed to be a metabolite of TRH. These findings suggest that the hypothalamus may regulate the cyclo(His-Pro) binding sites in the liver probably by controlling pancreatic SS secretion, since a VMH-lesion is reported to cause hypersecretion of pancreatic SS. 相似文献
2.
A 55-year-old woman was referred with a 4-month history of diplopia following functional endoscopic ethmoidectomy for chronic sinusitis. She had right hypertropia of 14 prism diopters in the primary position that increased to 30 prism diopters in down gaze. Her right eye showed a moderate limitation of motion in down gaze. Orbital imaging demonstrated a snapped right inferior rectus muscle. The inferior oblique muscle was transposed as an initial treatment for the snapped inferior rectus muscle. After surgery, the patient was orthophoric and obtained fusion in the primary position. 相似文献
3.
Morita Y Ujike H Tanaka Y Uchida N Nomura A Ohtani K Kishimoto M Morio A Imamura T Sakai A Inada T Harano M Komiyama T Yamada M Sekine Y Iwata N Iyo M Sora I Ozaki N Kuroda S 《Neuroscience letters》2005,376(3):182-187
Genetic contributions to the etiology of substance abuse and dependence are topics of major interest. Acute and chronic cannabis use can produce drug-induced psychosis resembling schizophrenia and worsen positive symptoms of schizophrenia. The endocannabinoid system is one of the most important neural signaling pathways implicated in substance abuse and dependence. The fatty acid amide hydrolase (FAAH) is a primary catabolic enzyme of endocannabinoids. To clarify a possible involvement of FAAH in the etiology of methamphetamine dependence/psychosis or schizophrenia, we examined the genetic association of a nonsynonymous polymorphism of the FAAH gene (Pro129Thr) by a case-control study. We found no significant association in allele and genotype frequencies of the polymorphism with either disorder. Because the Pro129Thr polymorphism reduces enzyme instability, it is unlikely that dysfunction of FAAH and enhanced endocannabinoid system induce susceptibility to either methamphetamine dependence/psychosis or schizophrenia. 相似文献
4.
5.
Suligoi B Massi M Galli C Sciandra M Di Sora F Pezzotti P Recchia O Montella F Sinicco A Rezza G 《Journal of acquired immune deficiency syndromes (1999)》2003,32(4):424-428
We evaluated a procedure for identifying recent HIV infections, using sequential serum samples from 47 HIV-positive persons for whom the seroconversion date could be accurately estimated. Each serum sample was divided into two aliquots: one diluted with phosphate-buffered saline and the other diluted with 1 M guanidine. We assayed the aliquots with the automated AxSYM HIV1/2gO test (Abbott Diagnostics Division), without modifying the manufacturer's protocol. We then calculated the avidity index (AI): the ratio of the sample/cutoff value for the guanidine aliquot to that of the phosphate-buffered saline aliquot. We analyzed 216 serum samples: 34 samples were collected within 6 months of seroconversion (recent seroconversions), and 182 were collected after 6 months. The mean AIs, by time from seroconversion, were 0.68 +/- 0.16 (within 6 months) and 0.98 +/- 0.10 (after 6 months) (P < 0.0001). AI of <0.90 correctly identified 88.2% of recent infections but misclassified as recent infections 13.2% of serum samples collected afterward. The probability of an infection being classified as recent and having AI of > or = 0.90 would be 0.7% in a population with 5% recent infections. AI can identify with a certain degree of accuracy recent HIV infections, and being a quantitative index, it provides different levels of sensitivity and specificity, depending on the selected cutoff value. The standard assay procedure is not modified. This test is simple and inexpensive and could be used for surveillance, decision-making in treatment, and prevention. 相似文献
6.
Takahiro Yamanaka Kenyu Nakayama-Iwatsuki Sora Fujimoto Naoki Hirono Jun Negishi Yasushi Tamada Masumi Hirabayashi Shinichi Hochi 《Transplantation proceedings》2021,53(5):1744-1750
Islet transplantation is a promising option for the clinical treatment of insulin-dependent diabetes, but a reliable islet cryopreservation/transplantation protocol should be established to overcome the donor shortage. The current study reports that a silk fibroin (SF) sponge disk can be used as a cryodevice for vitrification of large quantity pancreatic islets and the scaffold for subsequent subrenal transplantation in a rat model. The marginal islet mass (550 islet equivalents [IEQs]) on an SF sponge disk was vitrified-warmed and transplanted beneath the kidney capsule of a streptozotocin-induced diabetic rat with or without vascular endothelial growth factor (VEGF). Subrenal transplantation (no scaffold) of 550 IEQ fresh islets and post-warm islets vitrified on a nylon mesh device resulted in achieving euglycemia of recipient rats at 60% and 0%, respectively. Transplantation of 550 IEQ islets vitrified-warmed on an SF sponge disk failed to achieve euglycemia of recipient rats (0%), but the VEGF inclusion in the SF sponge disk contributed to acquiring the euglycemic recipients (33%). All cured recipient rats regained hyperglycemia after nephrectomy, and the histopathologic analysis exhibited a well-developing blood vessel network into the islet engrafts. Thus, an SF sponge disc was successively available as the cryodevice for islet vitrification, the transporter of the angiogenic VEGF, and the scaffold for subrenal transplantation in the rat model. 相似文献
7.
Total hip replacement has become one of the most successful surgical operations over the past 25 years. The duration of a total hip prosthesis depends on primary stability, and many studies have tried precisely to evaluate hip joint morphology to obtain excellent contact between bone and prosthetic component. This study performed a morphometric analysis of the human hip joint using, for the first time, the P40 plastination procedure. We cut 42 hip joint compounds into slices 3 mm thick; for exact distance measuring the sections were scanned into the computer. The following mean measurements for hip geometry were obtained: vertical diameter of acetabulum 4.894±0.274 cm, depth of acetabulum 1.643±0.245 cm, femoral head radius 2.268±0.149 cm, femoral neck length 4.3670±0.528 cm, acetabular perimeter 6.711±0.434 cm, vertical diameter of labrum acetabulare 4.759±0.476 cm, depth of labrum acetabulare 2.599±0.395 cm, sum of femoral head and neck lengths 6.759±0.550 cm, hip axis length 11.859±1.007 cm, femoral neck axis length 10.12±0.555 cm, and femoral neck diameter 3.349±0.276 cm. All of these data reveal a significant gender difference. Our aim was to indicate an unconventional and new method of gaining morphometric hip data by using plastination. 相似文献
8.
Clinical and experimental observations suggest that opiates can exert different influences on the perception of stimuli from distinct sensory modalities. Thermally-induced nociception is classically responsive to opiate agonists. mu-Opioid receptor-deficient transgenic mice are more sensitive to thermal nociceptive stimuli and morphine fails to attenuate the nociceptive responses to thermal stimuli in these animals. To enhance our understanding of opiate influences on mechanical sensitivity, we have examined withdrawal responses to a sequence of ascending forces of mechanical stimuli in mice with normal (wild type), half-normal (heterozygous) and absent (homozygous) mu-opioid receptor levels. We report data from mice examined without drug pretreatment or following pretreatment with morphine, the selective kappa-opioid agonist, U50488H, and the selective delta-opioid agonist, DPDPE. Saline-pretreated mice of each genotype displayed similar, monotonically increasing frequency of withdrawal responses to the graded stimuli. Subcutaneously administered morphine produced a dose-dependent reduction in withdrawal responses in wild type and heterozygous mice, but had no significant effect in homozygous mice. Intraventricular administration of DPDPE also reduced the frequency of paw withdrawal (FPW) in wild type mice, but not in homozygous mice. In contrast, systemic U50488H produced a dose-dependent attenuation of paw withdrawal in both wild type and homozygous mice. These findings suggest that (1) interactions of endogenous peptides with mu-opioid receptors may not play a significant role in the response to mechanical stimuli in drug-free animals, and (2) deficiency of mu-opioid receptors has no functional consequence on the response to the prototypical kappa-opioid receptor agonist, but decreases responses to the prototypical mu- and delta-opioid receptor agonists. 相似文献
9.
Several lines of evidence suggest that monoaminergic systems, especially dopaminergic and serotoninergic systems, modulate ethanol consumption. Humans display significant differences in expression of the vesicular and plasma membrane monoamine transporters important for monoaminergic functions, including the vesicular monoamine transporter (VMAT2, SLC18A2) and dopamine transporter (DAT, SLC6A3). In addition, many ethanol effects differ by sex in both humans and animal models. Therefore, ethanol consumption and preference were compared in male and female wild-type mice, and knockout (KO) mice with deletions of genes for DAT and VMAT2. Voluntary ethanol (2-32% v/v) and water consumption were compared in two-bottle preference tests in wild-type (+/+) vs heterozygous VMAT2 KO mice (+/-) and in wild-type (+/+) vs heterozygous (+/-) or homozygous (-/-) DAT KO mice. Deletions of either the DAT or VMAT2 genes increased ethanol consumption in male KO mice, although these effects were highly dependent on ethanol concentration, while female DAT KO mice had higher ethanol preferences. Thus, lifetime reductions in the expression of either DAT or VMAT2 increase ethanol consumption, dependent on sex. 相似文献
10.
Thermosoftening treatment of the nasotracheal tube before intubation can reduce epistaxis and nasal damage 总被引:6,自引:0,他引:6
Kim YC Lee SH Noh GJ Cho SY Yeom JH Shin WJ Lee DH Ryu JS Park YS Cha KJ Lee SC 《Anesthesia and analgesia》2000,91(3):698-701
We evaluated whether a thermosoftening treatment with warm saline of a nasotracheal preformed tube can improve navigability through the nasal passageways and reduce epistaxis and nasal damage. A total of 150 patients were randomly allocated to three groups: Group I (untreated tube group, n = 50), Group II (35 degrees C treated tube group, n = 50), and Group III (45 degrees C treated tube group, n = 50). In Groups II and III, the tubes were softened at 35 +/- 2 degrees C and 45 +/- 2 degrees C with warm saline, respectively. In Group I the tube was prepared at room temperature (25 +/- 2 degrees C). The incidence of epistaxis and nasal damage in Groups II and III was significantly less than that of Group I (P: < 0.05). Despite the more frequent incidence of smooth passage in Group III, no statistical difference was found among the groups. Logistic regression analysis also confirmed that epistaxis was more likely to be reduced when the tube had been thermosoftened (odds ratio = 1.46, 95% confidence interval = 1.02, 2.11). We conclude that simple thermosoftening treatment of the nasotracheal tube with warm saline helps to reduce epistaxis and nasal damage. IMPLICATIONS: Thermosoftening treatment of a nasotracheal tube with warm saline before intubation can effectively reduce epistaxis and nasal damage. This technique is safe, easy, and suitable for all types of tubes and does not require additional implements. 相似文献