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1.
Testicular seminoma with elevated serum human chorionic gonadotropin level (hCG-positive seminoma) is regarded as more malignant than marker-negative seminoma, although Its prognosis is still unclear. To clarify the malignant potential of seminoma with hCG production, the serum levels of the beta subunit of hCG (β-hCG) and lactic acid dehydrogenase (LDH) were examined in 35 and 40 patients, respectively, and the Immunohistochemical expression of β-hCG examined in 45 tumors. The elevation of the LDH serum level correlated to the Invasive status, metestatic status and poor outcome, while that of the serum β-hCG level correlated only to the metastatic status. Immunohistochemical expression of β-hCG was observed in syncytiotrophoblastic giant cells in 11 tumors and a few mononuclear seminoma cells In 36 tumors. Expression was not associated with the malignancy potential, except where the expression In mononuclear cells Inversely correlated to the invasive status. These results suggest that most seminomas produce a slight amount of hCG; that an elevated hCG serum level Indicates the pressnce of metastatic tumors and mainly reflects an increase in tumor volume but not in cellular malignancy potential; and that the LDH serum level, rather than hCG, is more useful as a prognostic indicator for patients with seminoma.  相似文献   
2.
The acute onset of peritoneal signs and shock in a 7year-old boy who had been hit in the epigastrium by a log-seesaw mandated surgical treatment. Enhanced computed tomography (CT) demonstrated complete laceration of the pancreas as well as duodenal injury, and a duodenoduodenostomy with distal pancreaticogastrostomy was subsequently performed. Temporary external drainage of the stomach and distal pancreas led to an uneventful recovery in the early postoperative period. Although the patient's postoperative development was appropriate for his age, the orifice of the distal pancreas spontaneously closed 2.5 years following surgery. We present this report to stress the fact that every effort should be made to preserve the pancreas following abdominal injury in children.  相似文献   
3.
To determine the healing potential and healing process of torn supraspinatus tendons, in situ hybridization was used to localize cells containing α1 type-I procollagen mRNA. Biopsy specimens of torn supraspinatus tendons from 19 patients with complete-thickness tears and 13 patients with incomplete-thickness tears were obtained during surgery. Four macroscopically normal supraspinatus tendons were obtained to serve as normal controls. Specimens were fixed in 10% buffered formalin and embedded in paraffin. A 22-mer oligonucleotide probe was labeled with digoxigenin and used as an in situ marker. The labeled cells were mainly composed of tenocytes and undifferentiated mesenchymal cells. In complete-thickness tears, the labeled cells at the proximal tendon stumps in the specimens that were obtained less than 4 months after trauma were significantly more abundant than in the specimens obtained 4 months or more after trauma. However, the number of labeled cells was maintained at the torn portion even in long-standing incomplete-thickness tears. The labeled cells at the margins of concomitant intratendinous extensions of the tears were detected even in the long-standing tears. The intratendinous extensions exhibited more labeled cell than were bursal-side or joint-side layers of the tendon substance in the incomplete-thickness tears (p < 0.05). The torn supraspinatus tendon may possess an intrinsic healing capability in the intermediate and late phases of tendon healing. Incomplete-thickness tears and concomitant intratendinous extensions can continue to rupture after the initial injury.  相似文献   
4.
PURPOSE: This study investigated the effect of parathyroid hormone (1-34) [PTH(1-34)] on bone reactions after tibial placement of titanium screw implants into ovariectomized rats. MATERIALS AND METHODS: Twelve-week-old female Wistar rats were divided into 3 groups of 24. The first group (Sham group) was sham-operated; the second group (OVX group) was ovariectomized only; and the third group (PTH group) was subcutaneously administered 30 microg/kg PTH in the dorsal region 3 days per week starting the fourth week after ovariectomy until the end of the experiment. Titanium screw implants were placed in the proximal metaphysis of the tibia of all 3 groups at 168 days after surgery. The animals were killed 7, 14, 28, and 56 days after implantation. Undecalcified sections were prepared and evaluated by light microscopy. Histomorphometric measurements were obtained using a computer-based image analyzer to quantify the unit bone mass around the implant and the rate of implant-bone contact. RESULTS: When PTH administration was started 21 days after ovariectomy, the volume density of bone around implants in the PTH group was almost the same as that of the Sham group throughout the entire observation period. This finding suggests that not only can intermittent human PTH(1-34) administration prevent resorption of newly generated trabeculae around an implant but also it can aid in the recovery of bone volume lost due to ovariectomy. CONCLUSION: When dental implants are applied to jaw bone showing trabecular bone loss, it may be possible to increase bone density around an implant by intermittent human PTH(1-34) administration and thereby improve clinical results.  相似文献   
5.
Recent studies have indicated that bone marrow stromal cells (BMSC) have the potential to improve neurologic function when transplanted into animal models of central nervous system disorders. However, how the transplanted BMSC restore the lost neurologic function is not clear. In the present study, therefore, we aimed to elucidate whether BMSC express the neuron-specific gamma-aminobutyric acid (GABA) receptor when transplanted into brain that has been subjected to cerebral infarction. METHODS: The BMSC were harvested from green fluorescent protein-transgenic mice and were cultured. The mice were subjected to permanent middle cerebral artery occlusion. The BMSC or vehicle was transplanted into the ipsilateral striatum 7 d after the insult. Using autoradiography and fluorescence immunohistochemistry, we evaluated the binding of 125I-iomazenil and the expression of GABA receptor protein in and around the cerebral infarct 4 wk after transplantation. RESULTS: Binding of 125I-iomazenil was significantly higher in the periinfarct neocortex in the BMSC-transplanted animals than in the vehicle-transplanted animals. Likewise, the number of the GABAA receptor-positive cells was significantly higher in the periinfarct neocortex in the BMSC-transplanted animals than in the vehicle-transplanted animals. A certain subpopulation of the transplanted BMSC expressed a neuron-specific marker, microtubule-associated protein 2, and the marker protein specific for GABAA receptor in the periinfarct area. CONCLUSION: These findings suggest that BMSC may contribute to neural tissue regeneration through migrating toward the periinfarct area and acquiring the neuron-specific receptor function.  相似文献   
6.
OBJECTIVE: Repetitive paired-pulse transcranial magnetic stimulation (TMS) at I-wave periodicity has been shown to induce a motor-evoked potential (MEP) facilitation. We hypothesized that a greater enhancement of motor cortical excitability is provoked by increasing the number of pulses per train beyond those by paired-pulse stimulation (PPS). METHODS: We explored motor cortical excitability changes induced by repetitive application of trains of four monophasic magnetic pulses (quadro-pulse stimulation: QPS) at 1.5-ms intervals, repeated every 5s over the motor cortex projecting to the hand muscles. The aftereffects of QPS were evaluated with MEPs to a single-pulse TMS, motor threshold (MT), and responses to brain-stem stimulation. These effects were compared to those after PPS. To evaluate the QPS safety, we also studied the spread of excitation and after discharge using surface electromyograms (EMGs) of hand and arm muscles. RESULTS: Sizes of MEPs from the hand muscle were enhanced for longer than 75min after QPS; they reverted to the baseline at 90min. Responses to brain-stem stimulation from the hand muscle and cortical MEPs from the forearm muscle were unchanged after QPS over the hand motor area. MT was unaffected by QPS. No spreads of excitation were detected after QPS. The appearance rate of after discharges during QPS was not different from that during sham stimulation. CONCLUSIONS: Results show that QPS can safely induce long-lasting, topographically specific enhancement of motor cortical excitability. SIGNIFICANCE: QPS is more effective than PPS for inducing motor cortical plasticity.  相似文献   
7.
We describe our experience with a patient in whom a traumatic right diaphragmatic hernia developed 4 years after sustaining injury and review cases of delayed diaphragmatic injury reported in Japan. The patient was a 28-year-old man who sustained a severe contusion of the right epigastric region and fractured a right rib in a traffic accident in September 1992. In August 1996, the patient presented with shortness of breath on effort or after meals. A chest roentgenogram revealed intestinal gas in the right side of the thoracic cavity. A right diaphragmatic hernia was diagnosed on the basis of a gastrointestinal series, and the patient was operated on. The hernial orifice extended anteriorly from the central tendon in an 11:00 direction and measured 11 x 6 cm. The small intestine, right side of the colon, and liver were herniated. A total of 297 cases of blunt traumatic diaphragmatic hernia were reported in Japan between 1981 and 1996, including 47 cases (left side, 32 cases; right side, 15 cases) of delayed diaphragmatic hernia, defined as occurring one month or more after injury. Diaphragmatic hernia should be considered as a possible diagnosis in patients with abnormal shadows in the thoracic region who have recently sustained injury or who have a past history of injury.  相似文献   
8.
Background Cat cry syndrome is an autosomal disease accompanying abnormal deletion of chromosome 5 and occurs in only 1 of 50,000 neonates. Scoliosis has been reported as a skeletal complication in cat cry syndrome. The characteristics and causes of scoliosis in this rare syndrome are unknown. The purpose of this study was to present the characteristics of scoliosis in cat cry syndrome and to speculate on its causative mechanisms. Methods We report on 11 cases (5 boys and 6 girls) of cat cry syndrome. Detailed investigations of scoliosis, as well as physical and imaging examinations, were performed to characterize scoliosis and its causes. Average age at initial diagnosis of scoliosis was 4.3 years, and average age at final examination was 11.8 years. Results The incidence of scoliosis was as high as 73% (8/11). Most cases show a single right thoracic curve. Of the 8 patients with scoliosis, 3 patients who had increased muscular tone showed marked progression of scoliosis with growth. Conclusions Muscular hypertonia may play a key role in the progression of scoliosis in cat cry syndrome.  相似文献   
9.
Recombinant human interleukin-11 (rHuIL-11) and recombinant human bone morphogenetic protein-2 (rHuBMP-2) have been shown to act synergistically in the induction of osteoblast differentiation. To determine whether these two proteins can be used clinically in fracture healing and reconstructive surgery, we investigated whether rHuIL-11 and rHuBMP-2 act synergistically to heal segmental bone defects in a rabbit model. A 1.5-cm segmental defect was created in the right ulnar diaphysis of 20 Japanese white rabbits. Polylactic-co-glycolic acid (PLGA)-coated gelatin sponges (PGS) permeated with rHuBMP-2 (n = 8), rHuIL-11 plus rHuBMP-2 (n = 8), or rHuIL-11 (n = 4) were implanted into the bone defects. Radiographs were scored by two independent observers for bone formation and union rates after 2, 3, 4, and 8 weeks. Bone formation was higher in rabbits implanted with rHuBMP-2 plus rHuIL-11 than in those implanted with rHuBMP-2 alone, reaching statistical significance after 4 weeks. At early time points, the union rate in rabbits implanted with rHuBMP-2 plus rHuIL-11 was higher than in rabbits implanted with rHuBMP-2. At 2, 4, and 8 weeks, new bone volume was significantly higher in rabbits administered rHuIL-11 plus rHuBMP-2 than in those given rHuBMP-2 alone. In contrast, mechanical testing after 8 weeks showed that bone strength in the two groups of rabbits was equivalent. These findings show that rHuIL-11 and rHuBMP-2 act synergistically to accelerate bone formation without affecting bone strength. Treatment with a combination of rHuIL-11 and rHuBMP-2 may thus be of great benefit in fracture healing and for patients undergoing reconstructive surgery.  相似文献   
10.
Subjects made a fast elbow extension movement to designated target in response to a go signal. In 45% of trials a stop signal was presented after the go signal, to which subjects were asked to stop the movement as rapidly as possible. The interstimulus interval (ISI), or time interval between the go and stop signals, was randomly varied between 0 and 200 ms. Electromyographic (EMG) activity was recorded from biceps brachii and triceps brachii. Subjects could sometimes completely inhibit initiation of the movements when the ISI was 0 ms, but could rarely do so when the ISI exceeded 100 ms. For responses that were initiated but stopped on the way, the amplitude of the movement decreased linearly as the time interval (=modification time) from the stop signal to EMG onset increased. The peak velocity increased linearly as the movement amplitude increased. This tendency was similar to those previously reported in step-tracking movements with various amplitudes. In spite of the similarity in the kinematics of the movement, the EMG pattern was different from that of step-tracking movement. While the initial agonist burst (AG1) decreased linearly after the modification time exceeded 100 ms, the antagonist burst (ANT) increased compared with the go trial for the modification time from 0 to 200 ms and decreased after the modification time exceeded 300 ms. This change of activation is analogous to functional modification of middle-latency reflex EMG response to load, or cutaneous perturbation. In conclusion, it is suggested that adaptive mechanisms, which would functionally modify the reflex responses, are also continuously working during voluntary movements in response to sudden changes in environmental information. Received: 3 November 1997 / Accepted: 3 February 1998  相似文献   
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