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排序方式: 共有783条查询结果,搜索用时 15 毫秒
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PL Van Lent AE Holthuysen N Van Rooijen LB Van De Putte WB Van Den Berg 《Canadian Metallurgical Quarterly》1998,57(7):408-413
OBJECTIVE: To investigate whether local removal of phagocytic synovial lining cells (SLCs) from the knee joint before onset of collagen type II arthritis has an effect on development of cartilage destruction. METHODS: Phagocytic SLCs were selectively depleted by a single injection of clodronate laden liposomes in the knee joint seven days before induction of collagen type II arthritis (CIA). Clodronate laden liposomes were given in one knee joint either alone or in combination with a short-term oral treatment of dexamethasone. Cartilage damage including proteoglycan depletion and chondrocyte death was measured in total knee joints sections stained with safranin-o or haematoxylin. RESULTS: Local removal of phagocytic SLCs, seven days before arthritis onset, prevented cell influx for the larger part. Chondrocyte death was significantly decreased in the SLC depleted arthritic joint both at an early (6 days) and late (12 days) time point after CIA induction. However, depletion of proteoglycans from femoral and patellar cartilage layers was not prevented. If the mild acute inflammation caused by a single clodronate laden liposome injection in the left knee joint, was blocked by a short-term (on consecutive days 9, 8, 7, 6, 5 before CIA onset) oral treatment with dexamethasone, cell influx, but also proteoglycan depletion was almost completely blocked. In the contralateral control right knee joint prominent cell influx and severe cartilage damage was observed, indicating that there was no effect of dexamethasone anymore at the onset of CIA. CONCLUSIONS: This study shows that removal of phagocytic lining cells before CIA induction, particularly in the presence of a short-term treatment with dexamethasone, decreases cartilage destruction. 相似文献
94.
EJ Olson WB Epperson DH Zeman R Fayer MB Hildreth 《Canadian Metallurgical Quarterly》1998,212(7):987-990
OBJECTIVE: To evaluate effectiveness of an allicin-based product in neonatal calves inoculated with Cryptosporidium parvum. DESIGN: Randomized controlled study. ANIMALS: 43 neonatal calves. PROCEDURE: Calves were inoculated with 1.5 x 10(8) or 7.5 x 10(5) C parvum oocysts within 2 days after birth. Calves were given an allicin-based product once after inoculation or daily for 7 days after inoculation or were not treated. Calves that developed diarrhea were treated by administration of the product. Fecal consistency scores and weight gains were statistically evaluated. RESULTS: Mean daily weight gain and severity of diarrhea in calves 4 to 21 days old were unaffected by prophylactic use of the product. However, intensive prophylactic administration may have delayed onset of C parvum-induced diarrhea in calves inoculated with the lower dose of oocysts. CLINICAL IMPLICATIONS: Administration of an allicin-based product did not alter duration of C parvum-induced diarrhea or enhance weight gain in neonatal calves. However, intensive prophylactic administration of an allicin-based product may delay onset of diarrhea in calves exposed to C parvum oocysts. 相似文献
95.
OBJECTIVE: To compare the clinical features of patients with chronic daily headache (CDH) with idiopathic intracranial hypertension without papilledema (IIHWOP) to those with normal CSF pressure. METHODS: A case-control study was conducted at a tertiary headache center. Cases consisted of 25 consecutive patients (24 women, 1 man, 38 +/- 6 years) with IIHWOP diagnosed between June 1989 and June 1996. IIHWOP was diagnosed if pressure was 200 mm CSF on two occasions and there was no papilledema. Control subjects consisted of patients with refractory CDH who had normal CSF pressure on lumbar puncture performed between June 1992 and June 1996 (n = 60, 50 women, 10 men, 36 +/- 11 years). A structured telephone follow-up was done from July 1996 to March 1997. Comparisons made between the two groups included demographics and headache profiles, both at the initial evaluation and at follow-up. RESULTS: The initial headache characteristics did not differ between the two groups: most had transformed migraine with analgesic overuse. Significant predictors of IIHWOP included pulsatile tinnitus (odds ratio [OR] = 13.0) and obesity (OR = 4.4). Visual symptoms did not differ significantly. The prognosis of the two groups of patients was similar. CONCLUSIONS: Pulsatile tinnitus and obesity suggest possible IIHWOP in patients with CDH. Treatment of patients with increased intracranial pressure was not satisfactory. 相似文献
96.
ME Mattix RE Hunt CL Wilhelmsen AJ Johnson WB Baze 《Canadian Metallurgical Quarterly》1995,23(3):262-268
The pathology of aerosolized staphylococcal enterotoxin B (SEB) was studied in the nonhuman primate. Six juvenile rhesus monkeys that received multiple lethal inhaled doses of SEB developed diarrhea and vomiting within 24 hr followed by depression, dyspnea, and shock. Three of 6 animals died by 52 hr. The most striking gross lesion in all 6 monkeys was diffuse severe pulmonary edema. Histologically, edema fluid was present within the peribronchiolar, peribronchial, and perivascular interstitium, alveolar septa, and alveoli. The adventitia of pulmonary vessels was infiltrated by lymphocytes, macrophages, and fewer neutrophils. Numerous large lymphocytes with occasional mitotic figures were within pulmonary vessels, often occluding alveolar capillaries. These cells were strongly immunoreactive with monoclonal antibodies against CD3, establishing them as T cells. Ultrastructurally, endothelial cell junctions were intact, and endothelial cells and type I pneumocytes contained numerous pinocytotic vesicles. Alveolar septal interstitial spaces were expanded by edema. The mechanism of these SEB-induced pulmonary lesions was not determined. We hypothesize that cytokine production by activated T cells may have caused vascular permeability changes leading to widespread pulmonary edema and shock. 相似文献
97.
This study evaluated the sexual knowledge (including contraceptive and reproductive knowledge), contraceptive use, and self-esteem among a sample of 158 male and female United States Navy sailors assigned to Navy ships. In spite of the fact that men and women viewed themselves as relatively knowledgeable with respect to contraception, results showed substantial knowledge deficits. Women demonstrated significantly greater sexual knowledge than men, and contraceptive/ reproductive knowledge was highly correlated with self-reported use of contraceptives. Finally, self-esteem was highly correlated with sexual knowledge and certain contraceptive use behaviors. 相似文献
98.
ZX Zhang XZ Gu WB Yin GJ Huang DW Zhang RG Zhang 《Canadian Metallurgical Quarterly》1998,42(5):929-934
PURPOSE: An attempt was made to define the role of radiotherapy before operation for AGC. METHODS AND MATERIALS: From January 1978 to May 1989, a prospective randomized trial on preoperative radiotherapy (R+S) vs. surgery alone (S) for AGC was carried out in 370 patients. Patients were randomized into a combined group (R+S, 171 patients) or a surgery alone group (S, 199 patients) by the envelope method. 8-MV photon or telecobalt was used for the preoperative radiation therapy, using anterior-posterior opposing parallel fields to deliver 40 Gy to the cardia, lower segment of the esophagus, fundus, lesser curvature, and hepatogastric ligament. Surgery was performed after 2 to 4 weeks rest. RESULTS: The 5- and 10-year survival rates of the R+S Group and the S Alone Group were 30.10% and 19.75%, 20.26% and 13.30%, respectively. The survival curves of these two groups diverged right from the beginning after the operation over the ninth year. Statistics by Kaplan-Meier log rank test proves that the difference is significant (chi2 = 6.74, p = 0.0094). The immediate results were: resection rate 89.5% and 79.4% (p < 0.01); pathologic stage after resection T2 12.9% and 4.5% (p < 0.01), T4 40.3% and 51.3% (p < 0.05), lymph node metastasis rates 64.3% and 84.9% (p < 0.001); operative mortality rates 0.6% and 2.5%; intrathoracic leak rates 1.8% and 4.0%, respectively. The causes of failure were: local uncontrol and recurrence 38.6% vs. 51.7% (p < 0.025), regional lymph node metastasis 38.6% vs. 54.6% (p < 0.005), distant metastasis 24.3% vs. 24.7%. CONCLUSION: Preoperative radiation therapy is able to improve the results of surgery for adenocarcinoma of the gastric cardia. 相似文献
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PURPOSE: The aim of this study was to evaluate chromatin condensation of human spermatozoa following swim-up compared to glass-wool separation. Semen aliquots from men attending an andrological outpatient clinic were processed by means of a swim-up procedure and glass-wool filtration. Chromatin condensation was recorded using aniline blue staining and results were reported according to color intensity of stained sperm heads. Morphometric measurements of sperm heads were performed on stained sperm samples. RESULTS: Glass-wool filtration resulted (i) in a significantly higher total motile sperm count (P < 0.0005) compared to swim-up and (ii) in a significantly higher percentage of normal chromatin-condensed spermatozoa compared to the ejaculate (P < 0.01). CONCLUSION: In contrast, comparing swim-up to the ejaculate, the percentage of matured nuclei (unstained spermatozoa) retrieved following swim-up was significantly lower (P < 0.005). Glass-wool filtration separates human spermatozoa according to motility and size of the sperm head. The size of the sperm head closely correlated with the chromatin condensation quality. 相似文献