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61.
The present study describes the distribution and cellular morphology of catecholaminergic neurons in the diencephalon and midbrain of the bottlenose dolphin (Tursiops truncatus). Tyrosine hydroxylase immunohistochemistry was used to visualize these putatively dopaminergic neurons. The standard A1-A17, C1-C3, nomenclature is used for expediency; however, the neuroanatomical names of the various nuclei have also been given. Dolphins exhibit certain tyrosine hydroxylase immunoreactive (TH-ir) catecholaminergic neuronal groups in the midbrain (A8, A9, A10) and diencephalon (A11, A12, A14), however, no neuronal clusters clearly corresponding to the A13 and A15 groups could be identified. The subdivisions of these neuronal groups are in general agreement with those of other mammals, but there is a high degree of species specificity. First, three TH-ir neuronal groups not identified in other species were found: in the ventral lateral peri-aqueductal gray matter, posterior dorsal hypothalamus, and rostral mesencephalic raphe. Second, the normal components of the substantia nigra (A9 or pars compacta, A9 lateral or pars lateralis, A9 ventral or pars reticulata) were extremely cell sparse, but there was a substantial expansion of the A9 medial and A10 lateral subdivisions forming an impressive 'ventral wing' in the posterior substantia nigra. The findings of this and previous studies suggest a distinct evolutionary trend occurring in the neuromodulatory systems in mammals. The results are discussed in relation to motor control, thermoregulation, unihemispheric sleep, and dolphin cognition. 相似文献
62.
63.
The objective of the study was to compare the efficacy of azithromycin, alone or with metronidazole, versus two standard multidrug regimens for the treatment of acute pelvic inflammatory disease (PID). Patients with PID were treated with once-daily intravenous (i.v.) azithromycin 500 mg for 1 day or 2 days followed by once-daily azithromycin 250 mg orally for a total of 7 days, alone or with three-times-daily metronidazole 400 mg or 500 mg i.v. then orally for a total of 12-14 days. The comparators were either metronidazole + doxycycline + cefoxitin + probenecid or doxycycline + amoxycillin/clavulanate given at standard recommended doses for up to 21 days. In total, 309 patients were treated for PID. The diagnosis was confirmed laparoscopically in 74.8% of patients. Rates of clinical success for azithromycin, alone (97.1%) or with metronidazole (98.1%), were comparable to those for the comparator regimens (94.6%). Eradication rates for Chlamydia trachomatis, Neisseria gonorrhoeae, Mycoplasma hominis and anaerobes were also comparable for each of the treatment groups. Both azithromycin regimens were well tolerated. In conclusion, azithromycin, alone or with metronidazole, provides a shorter, simpler treatment option for the successful management of acute PID. 相似文献
64.
In this study we used magnetic resonance imaging (MRI) to investigate neuroanatomical structure in the brain of a white whale (Delphinapterus leucas) that died from a large tumor within the brainstem. This specimen was also compared with a normal white whale brain using MRI. MRI scans of the white whale specimen show how the tumor deformed surrounding brain structure. Histopathological analysis indicated a poorly differentiated carcinoma of uncertain origin. These analyses demonstrate the usefulness of supplementing histological analyses of pathology with studies of gross morphology facilitated by MRI. 相似文献
65.
Three-dimensional coronary MR angiography performed with subject-specific cardiac acquisition windows and motion-adapted respiratory gating 总被引:10,自引:0,他引:10
Plein S Jones TR Ridgway JP Sivananthan MU 《AJR. American journal of roentgenology》2003,180(2):505-512
OBJECTIVE: In coronary MR angiography, data are conventionally accepted in only short and fixed periods of the cardiac and respiratory cycles. We hypothesized that a more flexible and subject-specific approach to cardiac and respiratory gating may shorten scanning times while maintaining image quality. SUBJECTS AND METHODS: We implemented an acquisition technique that uses subject-specific acquisition windows in the cardiac cycle and a motion-adapted gating window for respiratory navigator gating. Cardiac acquisition windows and trigger delays were determined individually from a coronary motion scan. Motion-adapted gating used a 2-mm acceptance window for the central 35% of k-space and a 6-mm window for the outer 65% of k-space. In 10 subjects, three-dimensional coronary MR angiograms of the right and left coronary systems were acquired with this technique (the "adaptive technique") as well as a conventional acquisition method, and the scanning times and image quality were compared. The adaptive technique was then applied prospectively to 40 patients who underwent coronary radiographic angiography. RESULTS: Scanning times with the adaptive technique were reduced by a factor of 2.3 for the right coronary artery and by a factor of 2.2 for the left coronary artery system compared with the conventional technique, mainly because we were able to use longer subject-specific acquisition windows in patients with low heart rates. Subjective and objective measurements of image quality showed no significant differences between the two techniques. Prospective evaluation of MR angiograms yielded a sensitivity and specificity of 74.3% and 88.2%, respectively, to detect significant coronary artery stenoses. CONCLUSION: Coronary MR angiography with subject-specific acquisition windows and motion-adapted respiratory gating reduces scanning times while maintaining image quality and provides high diagnostic accuracy for the detection of coronary artery stenosis. 相似文献
66.
Laparoscopic staging of pancreatic tumors induces increased invasive capacity in vitro 总被引:3,自引:0,他引:3
Introduction: Laparoscopy and laparoscopic ultrasound have a well-defined role in staging patients with pancreatic malignancy.
The effect of the hypoxic pneumoperitoneum induction on tumor biology is unknown. The authors investigated whether an in vitro
pneumoperitoneum augments the invasive capacity of pancreatic tumors and elucidate a mechanism by which this may occur. Methods:
A pancreatic (PSN-1) adenocarcinoma cell line was exposed to an in vtiro pneumoperitoneum (carbon dioxide (CO2) or helium)
for a maximum of 2 h or left in normal growth conditions (control). Cells were nonenzymatically harvested and placed in invasion
assays. These were performed over 72 h using Matrigel coated 8-mm Transwell filters and analyzed using MTS colorimetric assay.
Gelatin zymography was employed to assess the level of matrix metalloproteases (MMP) 2 and 9 (gelatinase A and B) secretion.
Expression of tissue inhibitor of metalloproteases 1 (TIMP-1) was assessed using ELISA (Biotrak). Inhibition of invasion assays
was performed using a specific gelatinase inhibitor (MMPI; Calbiochem). Results: The invasive capacity of pancreatic tumour
cells is augmented versus control in both helium (p <0.05) and CO2 (p <0.001) groups. Concomitant significant upregulation
of the gelatinase activity was demonstrated with both insufflants (p <0.05; 0.001, respectively). Enhanced invasion was attenuated
by the addition of a specific gelatinase inhibitor (p <0.05). Conclusions: These results indicate the invasive capacity of
pancreatic tumor cells is augmented by laparoscopic staging in vitro. This is in part mediated by increased gelatinase activity
and may be attenuated by the addition of specific inhibitors. 相似文献
67.
Identification of a human anti-CD55 single-chain Fv by subtractive panning of a phage library using tumor and nontumor cell lines. 总被引:7,自引:0,他引:7
A large naive human single-chain (sc) Fv phage library was used to search for tumor-associated antigens by panning with a lung adenocarcinoma cell line, 1264, and counter-selecting with a nontumor bronchial epithelial cell line, BEAS-2B. After three rounds of subtractive panning, 239 of 673 clones analyzed bound selectively to 1264 tumor cells in a phage ELISA. Diversity analysis of these tumor-selective clones by BstNI fingerprinting and nucleotide sequencing revealed 14 distinct scFv fragments. Four clones bound selectively to 1264 over BEAS-2B cells when analyzed by a more discriminating flow cytometric assay using scFv. Moreover, these clones showed only limited cross-reactivity to several primary human cell lines. One clone, LU30, also cross-reacted strongly with the lung adenocarcinoma line, A549. The LU30 antigen was identified as decay-accelerating factor (CD55) by expression cloning from a 1264 cDNA library. The mean number of decay-accelerating factor molecules on the surface of 1264 and BEAS cells used for panning and counter-selection was estimated as 75,000 +/- 5,000 and 13,000 +/- 10,000, respectively. Thus, phage library panning combined with expression cloning permits identification of antibodies and their cognate antigens for proteins that are differentially expressed on the surface of distinct cell populations. 相似文献
68.
Twenty-one children who had been diagnosed as having laryngomalacia by direct laryngoscopy in infancy were reviewed 7 to 12 years later. The natural history of the disease is documented. A wide variation in the time of onset and duration of the stridor was found and there was a high incidence of feeding difficulties. A previously reported association with mental retardation or cerebral palsy is not confirmed. 4 out of the 21 children had early speech problems. 相似文献
69.
In an infant with Menkes's steely-hair syndrome, early treatment (from 21 days of age) with parenteral copper failed to halt the disease. In addition to urinary tract abnormalities, panlobular emphysema was present a finding not previously noted in the syndrome. 相似文献
70.
We report our experiences of microbiological testing of operating theatres over a 10-year period. Major faults within the theatres can be detected by microbiological monitoring of air flow direction and the bioload in theatre air. We advocate that there should be a close cooperation between the microbiologist and the hospital engineering department for effective monitoring of theatre commissioning and upgrading. Also we recommend that contract work should be closely supervised particularly with respect to theatre ventilation systems. 相似文献