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1.
Levels of the nerve growth factor (NGF) have been measured in various brain regions of young and aged male and female rats of Wistar strain by means of a highly sensitive two-site enzyme immunoassay system for beta-NGF. Among the ten regions examined, the amount of NGF per wet weight of tissue was found to be highest in the hippocampus, irrespective of the sex and age. The NGF concentration in the hippocampus of female rats at 3 months of age was comparable to that of same aged males. Further, there was no significant difference in the NGF levels of the hippocampus between young and age males. However, the NGF level was significantly lower in aged females as compared to that in 3- or 4-month-old females, and hence the marked male-female difference was found in the NGF levels in aged Wistar rats.  相似文献   
2.
Buoyancy and sedimentation of human X- and Y-bearing sperm   总被引:4,自引:0,他引:4  
The buoyant and sedimentation behaviors of human X- and Y-bearing sperm were examined in discontinuous density gradients of Nycodenz. The washed sperm placed at the bottom of the discontinuous density gradients of Nycodenz (23-50% in 3% steps) were centrifuged at 250 x g for various periods. The buoyant velocity of X-bearing sperm was faster than that of Y-bearing sperm. The sedimentation profiles of human sperm in the discontinuous density gradients of Nycodenz (4-20% in 2% steps) showed that X-bearing sperm sedimented faster than Y-bearing sperm. The separation of X- and Y-bearing sperm by means of centrifugation usually have been based on the assumption that smaller Y and larger X chromosomes might provide the difference in their apparent densities. The present results suggest that the separation cannot be due merely to a difference in their densities.  相似文献   
3.
The results are reported on 214 patients treated for 270 mandibular fractures, using rigid internal fixation. Of these, 172 fractures (63.7%) in 131 patients had been re-evaluated at final follow-up in connection with plate and screw removal, on average 15.2 months, postoperatively. Although one-third of the patients had a history of alcohol abuse, and 86% were treated with a delay of more than 24 h (mean 3.2 days), good primary bone healing was observed in 93.9% of the patients. Infections, seen in 6.1% of the patients, were related exclusively to inadequate stability of the fracture. Malocclusion, observed in 18.2% of 159 dentate patients, was caused by incorrect plate bending and insufficient fracture reduction. Immediate postoperative dysfunction of the inferior alveolar nerve in 58.1% of the cases, and of the mandibular branch of the facial nerve in 12.7%, was followed by almost total recovery 1 year after operation. It is concluded that rigid internal fixation is a reliable method of treatment, especially indicated for patients with reduced healing capacity and poor co-operation.  相似文献   
4.
A 57-year-old man with a history of renal cell carcinoma presented with presyncope. He underwent nephrectomy years earlier followed by HLA-matched allogeneic peripheral-blood stem-cell transplantation. Echocardiographic investigation revealed a solitary right ventricle mass without contiguous vena caval or right atrial involvement. The mass was pathologically confirmed to be metastatic carcinoma in the right ventricular cavity. This case highlights the need to consider an underlying neoplastic syndrome in patients presenting isolated right ventricle mass by echocardiography.  相似文献   
5.
Langerhans cell histiocytosis is currently regarded as a reactive proliferative process of Langerhans cells rather than a malignancy. The disease is characterized by Langerhans cell infiltration of skin, lung, bone and other organs. We report a 74-year-old man with Langerhans cell histiocytosis who had generalized hemorrhagic and crusted papules. He also had diabetes insipidus. Because he did not have any severe constitutional symptoms or failure of vital organs, we applied topical PUVA treatment to his skin lesions, which responded well to the therapy. Diabetes insipidus, however, remained, in spite of X ray radiotherapy for the pituiary lesion.  相似文献   
6.
We measured the serum levels of manganese-superoxide dismutase (Mn-SOD) in acute myeloid leukemia (AML) and acute lymphoid leukemia (ALL). Serum Mn-SOD level for normal subjects was 94.1 +/- 23.5 ng/ml (mean +/- S.D.), the levels for AML and ALL patients were 159.6 +/- 77.1 ng/ml and 154.4 +/- 77.0 ng/ml, respectively. The serum Mn-SOD levels were unrelated to individual intracellular Mn-SOD levels, but correlated well with serum lactate dehydrogenase values. Regression of the leukemia was accompanied by decrease in the serum level of Mn-SOD. Serum Mn-SOD may thus serve as a measure of the activity of the disease.  相似文献   
7.
The study examines the osteoinductive potential of recombinant human morphogenetic protein 2 (rhBMP-2) radiologically and histologically in rat calf muscle.Ten male Wistar rats were used. rhBMP-2 50 μg was implanted with atelopeptide type I collagen as carrier in a pouch in rat calf muscle (n=5), and atelopeptide type I collagen alone was implanted in a further five as control. Induction of osteogenesis at 4 weeks was investigated.In all rats in which rhBMP-2 had been implanted there was a radio-opaque shadow in the muscle in the soft tissue radiograph. No such shadows were noted in the control group. Histological examination showed bony trabeculum, osteoblasts, and vigorous bone marrow including fatty marrow and angioid tissue both at the margins and in the center of the excised lumps in the rhBMP-2 group. There were no such signs in the control group.rhBMP-2 may be capable not only of inducing the formation of bone, but also of inducing a ‘self-supporting bone organ’ in the muscle.  相似文献   
8.
The alteration of the blood flow of the proper hepatic artery (PHA) on occlusion of the common hepatic artery (CHA) was studied intraoperatively using an electromagnetic flowmeter for 18 cases of malignant gastric tumor. PHA blood flow was 280 +/- 225 ml/min before CHA occlusion, and after the occlusion it was 170 +/- 132 ml/min, or 64 +/- 15% of the pre-occlusion flow (n = 16). The pulsation of PHA after CHA occlusion was palpable in all cases, and there were no complications due to ischemia in 17 cases which underwent Appleby's operation. These results suggested that there was fairly good blood flow in PHA maintained by collaterals after CHA occlusion and that, clear pulsation of PHA could be regarded as evidence of sufficient blood flow. Tissue blood flow (TBF) measurement for the liver and gall-bladder by H2 gas clearance method was also done in several cases of Appleby's operation and of other abdominal operations. TBF of the gallbladder was significantly lower in cases of Appleby's operation on the day of operation (p less than 0.02), but the difference between the two operation groups was not recognized 5 days after surgery, suggesting rather quick recovery of circulation. As to hepatic TBF, significant decrease following Appleby's operation could not be proved.  相似文献   
9.
10.
GOR (GOR47--1) is an epitope thought to be a host-derived antigen cross-reactive with hepatitis C virus (HCV) since it was isolated from a cDNA library of host animals reactive with sera of HCV-positive patients. An enzyme immunosorbent assay (ELISA) using this epitope as antigen is of sufficient sensitivity and specificity for screening patients with HCV. However, the relationship between GOR47--1 epitope and autoimmune phenomena associated with HCV infection or autoimmune hepatitis is controversial. Here we isolated the human GOR gene and found that the GOR47--1 epitope was not translated in humans due to a single base replacement from chimpanzee. Furthermore, we found some patients who had antibodies against another epitope, which is translated (GOR1--125) in humans, although there was no correlation between the existence of anti-GOR47--1 or anti-GOR1--125 Ab and autoimmune phenomena. Serum IgG levels did not influence the titres of these antibodies. Taken together with the results of several other studies, our finding that the GOR47--1 epitope cannot be translated into a protein suggests that there is little relationship between autoimmunity and the GOR gene product in human beings. We also discuss here the possible mechanism of cross-reactivity between HCV and the GOR gene product.  相似文献   
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