Objective To investigate the role of poly-lactic acid and agarose gelatin in promoting the functional recovery of the injured spinal cord. Methods Poly-lactic acid ( PLA) or agarose was embedded in the space between two stumps of the hemisectioned spinal cord. Immunohistochemistry was used to show astroglia proliferation and the infiltration of RhoA-positive cells. Locomotor activity recovery was evaluated by testing the function of hindlimbs. Results Astrogli-as and RhoA labeled non-neuronal cells accumulated in the area adjacent to the implant, while the number of RhoA-positive cells was decreased dramatically in the absence of implant. Animals implanted with agarose gelatin recovered more quickly than those with PLA, concomitant with a higher survival rate of the neurons. Conclusion Both PLA and agarose gelatin benefited the recovery of spinal cord after injury by providing a scaffold for astroglia processes. Modulation of the rigidity, pore size and inner structure of PLA and agarose gelatin might make these biodegradable materials more effective in the regeneration of the central nervous system (CNS). 相似文献
Objective: We compare the outcome of palliative pancreaticoduodenectomy and palliative surgical bypass in patients with advanced pancreatic carcinoma in our hospital. Recent published related articles are also reviewed. Methods: A respective analysis was performed comparing the perioperative parameters and outcome of 20 patients who underwent pancreaticoduodenectomy with a gross suspected cancer residue and 30 patients who underwent a surgical bypass, all of the patients were diagnosed as in advanced stages intra-operatively. Results: The two groups were comparable with patient characteristics, including age, gender, initial symptoms and concomitant major organ diseases. Tumors are similar in size and intra-operatively diagnosed as in advanced stages in both groups. All of the patients in the resection group were microscopically proved having cancer residue. One postoperative mortality occurred in the resection group (5%), zero in the bypass group (P > 0.05). Overall complications were significantly higher in the resection group (30% vs. 0, P < 0.01), including 2 patients developed Acute Respiratory Distress Syndrome (ARDS), zero in the bypass group (P < 0.01); hemorrhage and transfusions in the resection group were much more than that in the bypass group (P < 0.05). Hospital stay after resection was significantly longer than bypass (20 vs. 12 days, P < 0.01). Hospital fee after resection was 4 times more than after bypass (median 61.500 vs. 15. 300 yuan, P < 0.01). Survival was significantly longer after resection (median 12.2 vs. 7.1 months, P < 0.01). Conclusion: Our results show that palliative resection in advanced pancreatic carcinoma lengthens the survival time of the patients, but this is paid for significantly higher complications than bypass. 相似文献
Background: The study hypothesizes that nitrous oxide (N2O) releases opioid peptide in the brain stem, which results in inhibition of [gamma]-aminobutyric acid-mediated (GABAergic) neurons that tonically inhibit the descending noradrenergic inhibitory neurons (DNIN), resulting in activation of DNIN. In the spinal cord, activation of DNIN leads to the release of norepinephrine, which inhibits nociceptive processing through direct activation of [alpha]2 adrenoceptor and indirect activation of GABAergic neurons through [alpha]1 adrenoceptor. Arising from this hypothesis, it follows that GABAergic neurons will modulate the antinociceptive effect of N2O in diametrically opposite directions at supraspinal and spinal levels. The authors have tested this tenet and further examined the effect of midazolam, a GABA-mimetic agent, on N2O-induced antinociceptive effect.
Methods: Adult male Fischer rats were administered muscimol (GABAA receptor agonist) intracerebroventricularly (icv), gabazine (GABAA receptor antagonist) intrathecally (intrathecal), or midazolam intraperitoneally (intraperitoneal). Fifteen minutes later, they were exposed to air or 75% N2O and were subjected to the plantar test after 30 min of gas exposure. In some animals administered with midazolam, gas exposure was continued for 90 min, and the brain and spinal cord were examined immunohistochemically.
Results: The N2O-induced antinociceptive effect, which was attenuated by icv muscimol, intrathecal gabazine, and intraperitoneal midazolam. Midazolam inhibited N2O-induced c-Fos expression (a marker of neuronal activation) in the pontine A7 and spinal cord. 相似文献
In 1980, 267 patients with related symp-
toms were examined by tomography in our hos-
pital. Among them the styloid process (SP) of
128 cases were 30 mm or more in length. Pha-
ryngeal palpation was performed in 98. The SPs
of 61 patients were palpable and tender. Diagno-
sis was based on the related symptoms, tomogra-
phy, positive pharyngeal palpation and SP tender-
ness. Tomography showed that the longest SP
was 75 mm, while the longest one with symptoms
was 65 mm. The medial angulations of the SPs
were from 100 t0 27° and the anterior angulations
from 300 t0 50°. 相似文献
Transmission electron microscopic investigation
of standardized fractures of radii in 50 rabbits re
vealed that fibroblasts took part in the formation of
bony callus. The osteogenetic role played by the
fibroblasts can be categorized into the following 5
aspects: a. Fibroblasts synthesize and secrete Type
collagen fibrils and induce deposition of calcium
salt crystals in the collagen fibrils. b. Fibroblasts
produce matrix vesicles in their surroundings. These
matrix vesicles become calcified and turn into floccu-
lent calcospherules which coalesce and fuse into bone
tissues. c. Fibroblasts harbor calcium granules in
their mitochondria, thus providing calcium for calci-
fication of the intercellular matrix and bone forma
tion between the cells. d. Fibroblasts can transform
directly into osteocytes; there is bone formation
around the fibroblasts, the bone tissues surround the
fibroblast in the form of bony lacuna, then the fibro-
blast in the lacuna transforms into osteocyte. e.
Fibroblasts can undergo degenerative changes leading
to decease and replacement by bone tissues. 相似文献