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101.
We reviewed the computed tomography scans of 126 term infants, ages 1-6 months; leukohypodensity was found just under the cerebral cortex (subcortical leukohypodensity [SLD]) in 3 infants (2.4%) at 1-3 months of age. On subsequent computed tomography at over 4 months of age, SLD had disappeared and anterior horn predominant dilatation of the lateral ventricles had appeared. Only 1 patient with a distinct SLD had a poor neurodevelopmental outcome: spastic diplegia. SLD in our patients is believed to be closely related to subcortical leukomalacia because of the similar location and age distribution. Transient SLD may be a mild form of cystic SLD which would require careful computed tomography follow-up examination in early infancy.  相似文献   
102.
Effects of several cytokines on des-gamma-carboxy prothrombin (PIVKA II) synthesis in human hepatoma cells were investigated to know the process of PIVKA II production during a liver allograft rejection. Human recombinant interleukin-6 (IL-6) significantly stimulated the PIVKA II synthesis without any influence on the cell proliferation. The effect was almost completely neutralized by the specific anti-IL-6 antibody. Neither tumor necrosis factor (TNF), interleukin-1 (IL-1) nor interferon-gamma (IFN-gamma) had such a stimulative effect. IL-6 appears to stimulate PIVKA II production, and would be a candidate of factors that enhance the production of PIVKA II during a liver allograft rejection.  相似文献   
103.
A 48-year-old man had histologically demonstrated cardiac involvement associated with progressive muscular dystrophy. On coronary arteriography, numerous vascular communications between the coronary arteries and the left ventricular chamber were found. These vascular communications are considered to be the arterioluminal vessels. This is the first report of a case of progressive muscular dystrophy with numerous arterioluminal vessels.  相似文献   
104.
Many researchers have evaluated the motions of the shoulder girdle, especially scapular and humeral motion. However, few reports exist that describe motions of the acromioclavicular joint. The purpose of the present study was to analyze the 3D kinematics of the acromioclavicular joint during arm abduction using 3D MR images obtained by a vertically open MRI. Fourteen shoulders of seven volunteers were examined in seven static positions from 0 degrees to the maximum abduction in a seated position. 3D surface models of the clavicle and scapula were created, and the movements of the acromioclavicular joint from 0 degrees to each position were calculated using the volume-based registration technique. From these calculations, the translations were evaluated and the rotational motions were analyzed using the concept of the screw axis. In the anteroposterior direction, the clavicle translated most posteriorly (-1.9 +/- 1.3 mm) at 90 degrees of abduction and most anteriorly (1.6 +/- 2.7 mm) at maximum abduction. In the superoinferior direction, the clavicle translated slightly superiorly (0.9 +/- 1.9 mm). When analyzing relative motion of the scapula with respect to the clavicle, the scapula generally rotated about a specific screw axis passing through the insertions of both the acromioclavicular and the coracoclavicular ligaments on the coracoid process. The average rotation was 34.9 +/- 8.4 degrees.  相似文献   
105.
Background: Carbon dioxide is an important vasodilator of cerebral blood vessels. Cerebral vasodilation mediated by adenosine triphosphate (ATP)-sensitive K+ channels has not been demonstrated in precapillary microvessel levels. Therefore, the current study was designed to examine whether ATP-sensitive K+ channels play a role in vasodilation induced by mild hypercapnia in precapillary arterioles of the rat cerebral cortex.

Methods: Brain slices from rat cerebral cortex were prepared and superfused with artificial cerebrospinal fluid, including normal (Pco2 = 40 mmHg; pH = 7.4), hypercapnic (Pco2 = 50 mmHg; pH = 7.3), and hypercapnic normal pH (Pco2 = 50 mmHg; pH = 7.4) solutions. The ID of a cerebral parenchymal arteriole (5-9.5 [mu]m) was monitored using computerized videomicroscopy.

Results: During contraction to prostaglandin F2[alpha] (5 x 10-7 m), hypercapnia, but not hypercapnia under normal pH, induced marked vasodilation, which was completely abolished by the selective ATP-sensitive K+ channel antagonist glibenclamide (5 x 10-6 m). However, the selective Ca2+-dependent K+ channel antagonist iberiotoxin (10-7 m) as well as the nitric oxide synthase inhibitor NG-nitro-l-arginine methyl ester (10-4 m) did not alter vasodilation. A selective ATP-sensitive K+ channel opener, levcromakalim (3 x 10-8 to 3 x 10-7 m), induced vasodilation, whereas this vasodilation was abolished by glibenclamide.  相似文献   

106.
Prostaglandin E1 (PGE1) has several potential therapeutic effects, including cytoprotection, vasodilation, and inhibition of platelet aggregation. This study investigates the protective action of PGE1 against hepatic ischemia/reperfusion injury in vivo using a complementary DNA microarray. PGE1 or saline was continuously administered intravenously to mice in which the left lobe of the liver was made ischemic for 30 minutes and then reperfused. Livers were harvested 0, 10, and 30 minutes postreperfusion. Messenger RNA was extracted, and the samples were labeled with two different fluorescent dyes and hybridized to the RIKEN set of 18,816 full-length enriched mouse complementary DNA microarrays. Serum alanine aminotransferase and aspartate aminotransferase levels at 180 minutes postreperfusion were significantly lower in the PGE1-treated group than in the saline-treated group. The cDNA microarray analysis revealed that the genes encoding heat-shock protein (HSP) 70, glucose-regulated protein 78, HSP86, and glutathione S-transferase were upregulated at the end of the ischemic period (0 minutes postreperfusion) in the PGE1 group. Our results suggested that PGE1 induces HSPs immediately after ischemia reperfusion. HSPs might therefore play an important role in the protective effects of PGE1 against ischemia/reperfusion injury of the liver.  相似文献   
107.
We present a case of lung cancer that showed false positive accumulation in an 18F fluorodeoxyglucose positron emission tomography (FDG-PET) scan following induction chemotherapy for suspected metastasis and progression of malignancy. A 66-year-old man was diagnosed with squamous cell carcinoma in the lung, classified as clinical stage IIIA (T2N2M0), and underwent induction chemotherapy. An FDG-PET scan prior to chemotherapy demonstrated accumulation only in the tumor, whereas following treatment it revealed a strong accumulation not only in the tumor, but also in the supraclavicular lymph nodes, which indicated lymph node metastasis. The patient underwent a biopsy of the right supraclavicular lymph node and mediastinoscopy, after which all dissected lymph nodes showed sarcoid reactions and no tumor cells were found pathologically. We concluded that when evaluating the effect of induction chemotherapy for malignancy, a sarcoid reaction might lead to the false positive accumulation of FDG.  相似文献   
108.
Standard imaging techniques using a curved linear array echoendocope are summarized to facilitate the attainment of expertise in endoscopic ultrasonography and endoscopic ultrasound‐guided fine needle aspiration, and to promote the widespread use of this diagnostic and therapeutic tool. Typical images of the mediastinal organs, the bilio‐pancreatic systems and neighboring organs by scanning from the esophagus, stomach, duodenal bulb, and descending portion of the duodenum, are shown in a sequential manner. The basic techniques of endoscopic ultrasound‐guided fine needle aspiration are also presented.  相似文献   
109.
OBJECTIVE: To investigate the effects of muscle fatigue induced by low-level isometric jaw-clenching and subsequent glutamate-evoked muscle pain on the exteroceptive suppression (ES) response and resting electromyographic (EMG) activities in human jaw muscles. METHODS: The resting EMG activity and the ESs were recorded before (baseline), after low-level jaw-clenching (Post1), after subsequent glutamate or isotonic saline injections into the left masseter (Post2), and 60 min after the clenching (Post3) in 23 healthy volunteers. RESULTS: The late ES (ES2) showed more inhibition at Post1 compared with baseline (P<0.05). It was less inhibited after both types of injections (Post2), and increased at Post3 again (P<0.05) with no significant difference between the glutamate and isotonic saline sessions. The resting EMG activity increased at Post1 and Post2 (P<0.05). The glutamate injection further increased the resting EMG activity in the injected muscle (P<0.01). CONCLUSIONS: Muscle fatigue influences inhibitory reflex pathways in jaw-closing muscles and subsequent acute muscle pain potentiates the local increase in the resting EMG activity of the painful muscle. SIGNIFICANCE: Muscle fatigue which can be observed in patients with oral dysfunctions may interact with nociceptive regulation and influence the clinical presentation of jaw symptoms and function.  相似文献   
110.
Background Few previous studies have analyzed the incidence of bone metastases in a defined population of Japanese breast cancer patients and their prognosis after chemotherapy. Methods This is a retrospective cohort study. We investigated 695 patients who underwent surgery for breast cancer. The strategy of adjuvant therapy was as follows. Patients with both estrogen receptors (ERs) and progesterone receptors (PgRs) had endocrine therapy as initial adjuvant therapy (n = 239). Patients with neither ERs nor PgRs had chemotherapy. When metastasis to other organs, including bone, was identified, patients received chemotherapy. The survival rates after surgery and after the onset of bone metastasis, as well as the incidence of bone metastasis, were calculated. We also evaluated the prognostic and predictive factors. Results Bone metastases developed in 148 of 695 patients. All 148 received chemotherapy, and 121 of them developed spinal metastases. The 5-year survival rate after bone metastases was 26.1%. Prognostic factors for bone metastases were visceral metastases and PgR status. Cord compression was observed in 17 of the 148 patients, with the thoracic spine being the most common. The 1-year survival rate for patients with bone metastases who received chemotherapy was 66.3%, whereas that of patients with paralysis after spinal metastases was 17.6%. Within 6 months of the development of spinal cord compression, 70.6% of the patients died. Conclusions We reported the incidence and prognostic factors for a defined population of Japanese breast cancer patients with bone and spinal metastases. Our results suggest that the expected survival time for patients with paralysis who received adequate endocrine therapy or chemotherapy is generally poor. However, to detect a predictive factor of long survival after paralysis and establish the indications for surgery, a comparative study among large groups of patients with paralysis and with different backgrounds is necessary.  相似文献   
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