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101.
The sensitivity of dopamine D2-like receptors in morphine-withdrawn rats was studied using the selective agonist quinpirole. Morphine was administered twice daily increasing the daily dose from 20 to 50 mg/kg during 7 days. Twenty-four hours after the last morphine administration the rats were given quinpirole (0.01-1 mg/kg) and their behavior was assessed. Withdrawal from repeated morphine treatment enhanced yawning behavior and penile erections induced by small doses (0.01-0.1 mg/kg) as well as the intensity of stereotypy induced by a large dose (1.0 mg/kg) of quinpirole. In the morphine-withdrawn rats the dose of 1 mg/kg of quinpirole caused less yawning than in the control rats, whereas the number of erections induced by this dose was enhanced as compared with the control animals. In the control rats, the striatal and limbic concentrations of dopamine metabolites, 3,4-dihydroxphenylacetic acid (DOPAC), and homovanillic acid (HVA), were not clearly affected by the smallest dose of quinpirole. However, the small dose of quinpirole (0.01 mg/kg) significantly reduced the levels of DOPAC and HVA in the striatum and limbic forebrain of the rats withdrawn from morphine either for 24 or 48 h. These findings indicate that withdrawal from repeated morphine treatment enhances the sensitivity of dopamine D2-like receptors.  相似文献   
102.
We report the outcome of 177 consecutive primary Charnley total hip arthroplasties inserted with Boneloc cement between November 1991 and November 1993. There were 107 women and 70 men. The mean age at the time of the operation was 71 years. 11 patients (13 hips) died during the follow-up period and 3 patients were too weak to attend a follow-up examination. Of the 161 remaining hips, 4 had been revised because of deep infection. The mean follow-up time for the remaining 157 hips was 2 (0.5-3) years. 24 hips had been revised and 6 are waiting for revision because of stem loosening. Of the remaining 127 hips, 72 showed radiographic signs of stem loosening and 2 hips were probably loose. Osteolysis was seen around the femoral component in 56 hips.  相似文献   
103.
We describe an example of a rare benign intranodal haemorrhagic spindle cell tumour (also called intranodal myofibroblastoma), occurring in a lymph node of the right inguinal region of a 53 year-old male patient. This is the first documentation of this tumour in the Danish literature. The lesion presents typically as a unilateral, solitary, painless inguinal lump. The microscopic appearance is characterized by proliferating spindle-shaped cells, interstitial haemorrhage and amianthoid fibers. Differential diagnosis includes primary and secondary lymph node tumours, such as Kaposi's sarcoma; metastatic spindle cell carcinoma; melanoma; neurilemmoma and soft tissue sarcomas. The clinical behaviour of the tumour is benign and local excision is the treatment of choice.  相似文献   
104.
OBJECTIVE: To describe the presentation and incidence of Kaposi's sarcoma (KS) in a cohort of women infected with HIV and to compare their clinical characteristics with men at the same institution. DESIGN: Retrospective chart and database review. SETTING: Adult clinical AIDS program outpatient clinics at a municipal teaching hospital. RESULTS: One hundred and seven people with KS were found of whom twelve (11.2%) were women. The prevalence of KS in women was 3.6% compared with 9.9% among men (P < 0.001). Women born outside the United States were at increased risk of developing KS (P < 0.05). At initial KS presentation, no difference in HIV stage or CD4 count was found between men and women. Women presented with more advanced KS than men, with increased incidence of non-cutaneous disease (P < 0.001), lymphedema (P < 0.0001), lymph-node disease (P < 0.0001) and visceral disease (P = 0.03). Women had decreased survival after KS diagnosis compared to men, although the difference was not significant (P = 0.41). CONCLUSIONS: KS is not a rare diagnosis in HIV-infected women followed at our institution. Although the increased risk of KS in men is most likely to be related to differences in exposure, the sex-related differences in presentation and course may be due in part to delay in diagnosis. KS should be considered in the spectrum of HIV-related complications in women as well as in men.  相似文献   
105.
Mono iodinated analogues of biphalin [(Tyr-D-Ala-Gly-Phe-NH-)2], both nonradioactive [I-Tyr1]biphalin and radioactive [125I-Tyr1]biphalin have been synthesized. The radioligand binding profiles of these compounds for two types of tissues, rat brain membranes, and NG108-15 cell membranes were identical to the parent biphalin. This is additional evidence for the hypothesis that biphalin behaves like a monomeric ligand and that only one intact tyrosine is necessary for high biological activity. The second tyrosine could be used for successful radioiodination which may greatly simplify biochemical and pharmacological studies of biphalin. The results of receptor binding studies show that the binding of both biphalin and [I-Tyr1]biphalin to the delta and mu opioid receptors are not independent. [125I-Tyr1]Biphalin binds to delta receptors as shown in NG108-15 cell membranes. Nevertheless, [125I]biphalin binding to delta receptors in rat brain membranes was hardly evident and mu receptor binding predominated or at least was much more readily detectable in this preparation.  相似文献   
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The McrBC restriction system has the ability to restrict DNA containing 5-hydroxymethylcytosine, N4-methylcytosine, and 5-methylcytosine at specific sequences. The mcrB gene produces two gene products. The complete mcrB open reading frame produces a 51-kDa protein (McrB(L)) and a 33-kDa protein (McrB(S)). The smaller McrB polypeptide is produced from an in-frame, internal translational start site in the mcrB gene. The McrB(S) sequence is identical to that of McrB(L) except that it lacks 161 amino acids present at the N-terminal end of the latter protein. It has been suggested that McrB(L) is the DNA binding restriction subunit. The function of McrB(S) is unknown, although there has been speculation that it plays some role in the modulation of McrBC restriction. Studies of the function of McrB(S) have been challenging since it is produced in frame with McrB(L). In this study, we tested the effects of underproduction (via antisense RNA) and overproduction (via gene dosage) of mcrBC gene products on restriction levels of the mcrBC+ strain JM107. Among the parameters monitored was the induction of SOS responses, which indicate of DNA damage. Evidence from this study suggests that McrB(S) is necessary for stabilization of the McrBC restriction complex in vivo.  相似文献   
109.
Fibroblast growth factor (FGF) signaling has been implicated in the patterning of mesoderm and neural lineages during early vertebrate development. In the mouse, FGF receptor-1 (FGFR1) is expressed in an appropriate spatial and temporal manner to be orchestrating these functions. Mouse embryos homozygous for a mutated Fgfr1 allele (fgfr1(delta tmk)) die early in development, show abnormal growth and aberrant mesodermal patterning. We have performed a chimeric analysis to further study FGFR1 function in the morphogenesis and patterning of the mesodermal germ layer at gastrulation. At E9.5, fgfr1(delta tmk)/fgfr1(delta tmk) cells showed a marked deficiency in their ability to contribute to the extra-embryonic, cephalic, heart, axial and paraxial mesoderm, and to the endoderm of chimeric embryos. Analysis at earlier stages of development revealed that fgfr1(delta tmk)/fgfr1(delta tmk) cells accumulated within the primitive streak of chimeric embryos, and consequently failed to populate the anterior mesoderm and endodermal lineages at their inception. We suggest that the primary defect associated with the fgfr1(delta tmk) mutation is a deficiency in the ability of epiblast cells to traverse the primitive streak. fgfr1(delta tmk)/fgfr1(delta tmk) cells that accumulated within the primitive streak of chimeric embryos tended to form secondary neural tubes. These secondary neural tubes were entirely fgfr1(delta tmk)/fgfr1(delta tmk) cell derived. The adoption of ectopic neural fate suggests that normal morphogenetic movement through the streak is essential not only for proper mesodermal patterning but also for correct determination of mesodermal/neurectodermal cell fates.  相似文献   
110.
TP Whetzel  CJ Saunders 《Canadian Metallurgical Quarterly》1997,100(3):582-7; discussion 588-90
Knowledge of the specific cutaneous or surface regions supplied by constant named arterial sources has allowed for increasing clinical application of flap transfers of tissue. Despite the routine use of intraoral flaps for reconstruction of congenital or acquired defects of the oral cavity and pharynx, no previous investigation has centered on understanding the surface or mucosal arterial territories of the oral cavity. In a cadaver study, six mucosal territories of the intraoral cavity were defined using selective ink and lead oxide injections through named arteries. The anatomical boundaries of these territories are predictable and constant in location for different cadavers. The six contiguous territories are based on the buccal, labial, inferior alveolar, ascending palatine, ascending pharyngeal, and lingual arteries. This study supports the safe vascular basis of existing clinical procedures of the intraoral cavity and may have implications for the design of new intraoral reconstructive procedures.  相似文献   
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