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991.
This study investigated whether the lymphocyte count is a useful indicator to assess surgical damage following extracorporeal bypass. In Study 1, to investigate the correlation between extracorporeal circulating time (ECCT) and lymphocyte counts, 40 elective CABG patients were studied retrospectively. The lymphocyte recovery ratio (LRR), which represented the actual lymphocyte count divided by the preoperative lymphocyte count, was determined preoperatively, and on postoperative day (POD) 1, POD 3, and POD 5. In Study 2, the correlation between the interleukin-8 (IL-8) level and LRR was examined prospectively in elective CABG patients (n = 20). We measured the LRR and serum IL-8 levels preoperatively and during extracorporeal circulation (ECC) at 5 min, at the end of ECC, and 1, 3, and 12 h following ECC termination. Study 1 showed that the LRR decreased until POD 1 and gradually increased thereafter. The LRR had a negative correlation with the ECCT. In Study 2, the IL-8 level demonstrated a time course opposite to that of the LRR; it increased until 3 h after ECC termination and declined thereafter. There was a significant negative correlation between the LRR on POD 3 and the IL-8 level at 3 h after ECC termination. In summary, long-term ECC induced significant and prolonged lymphocytopenia. The LRR had a negative correlation with IL-8. These results indicated that the LRR may represent the degree of surgical stress following ECC; therefore, the counting of lymphocytes can be a quite useful bedside monitor to assess surgical damage and prognosis.  相似文献   
992.
I Oda  B W Cunningham  K Abumi  K Kaneda  P C McAfee 《Spine》1999,24(16):1634-1638
STUDY DESIGN: After total spondylectomy, five types of spinal reconstruction techniques were compared biomechanically. OBJECTIVES: To evaluate the stability provided by five reconstruction methods after total spondylectomy. SUMMARY OF BACKGROUND DATA: Total spondylectomy presents a worst-case scenario for spinal reconstruction. However, few investigators have biomechanically investigated spinal reconstruction stability after total spondylectomy. METHODS: Eight human cadaveric spines (T11-L5) were used. After intact analysis, a total spondylectomy was performed at L2 and reconstructed using Harms titanium mesh (Depuy-Motech, Warsaw, IN) as an anterior strut. Anterior, posterior, or circumferential instrumentation techniques were then performed using the Kaneda SR and ISOLA pedicle screw systems (AcroMed Corp., Cleveland, OH) as follows: 1) anterior instrumentation at L1-L3 with multisegmental posterior instrumentation at T12-L4 (AMP), 2) anterior instrumentation at L1-L3 with short posterior instrumentation at L1-L3 (ASP), 3) anterior instrumentation at L1-L3 (A), 4) multilevel posterior instrumentation at T12-L4 (MP), and 5) short posterior instrumentation at L1-L3 (SP). Nondestructive biomechanical testing was performed under axial compression, flexion-extension, and lateral bending loading modes. RESULTS: Only circumferential instrumentation techniques (AMP, ASP) exhibited higher stiffness than the intact spine in all loading modes (P < 0.05). Short circumferential fixation provided more stability than did multilevel posterior instrumentation (P < 0.05). Multilevel posterior fixation provided more stiffness than did short posterior and anterior instrumentation alone (P < 0.05). CONCLUSIONS: Only circumferential fixation techniques provide more stability than the intact spine in all testing modes. Short circumferential instrumentation provides more stability than multilevel posterior instrumentation alone and requires fewer levels of spinal fusion.  相似文献   
993.
994.
The present study was undertaken to determine whether urinary excretion of aquaporin-2 (AQP-2) water channel under ad libitum water intake is of value to differentiate polyuria caused by psychogenic polydipsia from central diabetes insipidus. A 30-min urine collection was made at 0900 h in 3 groups of: 11 patients with central diabetes insipidus (22-68 yr old), 10 patients with psychogenic polydipsia (28-60 yr old), and 15 normal subjects (21-38 yr old). In the patients with central diabetes insipidus, the plasma arginine vasopressin level was low despite hyperosmolality, resulting in hypotonic urine. Urinary excretion of AQP-2 was 37 +/- 15 fmol/mg creatinine, a value one-fifth less than that in the normal subjects. In the patients with psychogenic polydipsia, plasma arginine vasopressin and urinary osmolality were as low as those in the patients with central diabetes insipidus. However, urinary excretion of AQP-2 of 187 +/- 45 fmol/mg creatinine was not decreased, and its excretion was equal to that in the normal subjects. These results indicate that urinary excretion of AQP-2, under ad libitum water drinking, participates in the differentiation of psychogenic polydipsia from central diabetes insipidus.  相似文献   
995.
To characterize the dengue epidemic that recently occurred in Malaysia, we sequenced cDNAs from nine 1993-1994 dengue virus type-3 (DEN-3) isolates in Malaysia (DEN-3 was the most common type in Malaysia during this period). Nucleic acid sequences (720 nucleotides in length) from the nine isolates, encompassing the precursor of membrane protein (preM) and membrane (M) protein genes and part of the envelope (E) protein gene were aligned with various reference DEN-3 sequences to generate a neighbor-joining phylogenetic tree. According to the constructed tree, the nine Malaysian isolates were grouped into subtype II, which comprises Thai isolates from 1962 to 1987. Five earlier DEN-3 virus Malaysian isolates from 1974 to 1981 belonged to subtype I. The present data indicate that the recent dengue epidemic in Malaysia was due to the introduction of DEN-3 viruses previously endemic to Thailand.  相似文献   
996.
This report describes a PCR primer pair that targets the algD GDP mannose gene of Pseudomonas aeruginosa and produces a specific 520-bp PCR product useful for P. aeruginosa identification. This PCR assay was tested with 182 isolates of P. aeruginosa and 20 isolates of other bacterial species, and demonstrated 100% specificity and sensitivity. The test was also able to detect P. aeruginosa directly in clinical samples such as sputum or throat swabs obtained from cystic fibrosis patients. The combination of this primer with a universal bacterial primer, acting as a control to assess DNA quality in the sample, resulted in a robust PCR method that can be used for rapid P. aeruginosa detection.  相似文献   
997.
Fibrous dysplasia and osteofibrous dysplasia are both benign fibro-osseous lesions of the bone and are generally seen during childhood or adolescence. Histologically, the features of these bone lesions sometimes look quite similar, but their precise nature remains controversial. We retrospectively studied clinicopathologic findings in 62 cases of fibrous dysplasia and 20 cases of osteofibrous dysplasia with regard to their anatomic location and histological appearance. From among these cases, the immunohistochemical expressions of c-fos and c-jun proto-oncogene products and bone matrix proteins of type I collagen, osteonectin, osteopontin, and osteocalcin were evaluated in 20 typical fibrous dysplasias and 17 osteofibrous dysplasias using paraffin sections, and these expressions were then assessed semiqnantitatively. Microscopically, fibrous dysplasia showed various secondary changes, such as hyalinization, hemorrhage, xanthomatous reaction, and cystic change in 22 of the 62 cases (35%). This was a higher incidence than in osteofibrous dysplasia, in which only 2 of the 20 cases (10%) showed such changes. In the elderly fibrous dysplasia cases, the cellularity of fibroblast-like cells was rather low, and those cases were hyalinized. Almost all of the cases of fibrous dysplasia and osteofibrous dysplasia showed positive expressions of c-fos and c-jun products. The expressions of type I collagen and osteopontin showed no difference between fibrous dysplasia and osteofibrous dysplasia. Immunoreactivity for osteonectin in bone matrix was detected in only 1 case of fibrous dysplasia (1 of 20), whereas it was recognized in 14 of the 17 cases of osteofibrous dysplasia. Furthermore, the immunoreactivity for osteocalcin in bone matrix and fibroblast-like cells was higher in fibrous dysplasia than it was in osteofibrous dysplasia, semiquantitatively. Our immunohistochemical results regarding osteonectin and osteocalcin suggest that the bone matrix of fibrous dysplasia is somewhat more mature than that of osteofibrous dysplasia, and that the fibroblast-like cells in fibrous dysplasia share some phenotypic features with osteoprogenitor ceils of normal osteogenic tissues. Fibrous dysplasia and osteofibrous dysplasia share Some similar histological features, including c-fos and c-jun expressions, although different clinicohistologic features and immunohistochemical expressions of osteonectin and osteocalcin were observed. These features suggest that the mechanisms behind the development of fibrous dysplasia and osteofibrous dysplasia are similar, but this is not necessarily indicative of a closer relationship between the 2 diseases.  相似文献   
998.
We present a case of malignant fibrous histiocytoma of the spermatic cord. An 86-year-old man was admitted to the hospital with a right painless scrotal mass. Under the diagnosis of a testicular tumor, right radical orchiectomy was performed. Grossly, the tumor firmly adhered to the spermatic cord. The right testis and epididymis were normal. The histologic diagnosis was malignant fibrous histiocytoma. There was local recurrence 2 months after surgery. The recurrent tumor was resected with the surrounding soft tissue, but the patient died 5 months after the initial operation.  相似文献   
999.
To evaluate the effects of milrinone on blood flow in the left internal mammary artery (LIMA) grafts and hemodynamic variables, we conducted a prospective randomized study. Twenty-four patients undergoing coronary artery bypass grafting were randomized to receive milrinone treatment (Milrinone; n = 12) or no milrinone treatment (Control; n = 12). Milrinone was given after induction of anesthesia at a speed of 0.5 microgram/kg/min for 24 hours. After start of cardiopulmonary bypass (CPB), CPB perfusion flow was adjusted to 2.4 l/m2 and LIMA blood flow was measured. Blood samples for determination of plasma cAMP levels were collected and hemodynamic measurements were also assessed perioperatively. LIMA blood flow was significantly greater in Milrinone than that in Control (40 +/- 4 vs 29 +/- 4 ml/min/m2, p < 0.05). Plasma levels of cAMP were significantly (p < 0.05) greater in Milrinone than those in Control at tha start of CPB (18 +/- 1 vs 13 +/- 1 pmol/ml) and at the end of CPB (24 +/- 2 vs 17 +/- 2 pmol/ml). Systemic vascular resistance was significantly (p < 0.05) lower and cardiac index was significantly (p < 0.05) greater in Milrinone than those in Control postoperatively. With its positive inotropic and systemic vasodilator activities, milrinone may have direct vasodilator effect on LIMA.  相似文献   
1000.
M Oda  F Udaka  T Kubori  N Oka  M Kameyama 《Brain and nerve》1999,51(12):1075-1079
A 15-year-old male developed symmetrical weakness of the limb muscles. He had not had any previous developmental disorders except delayed initiation of walking. Flexion contraction of ankle joint and pes cavus deformity were seen. The cerebrospinal fluid protein concentration was elevated. Nerve conduction study showed severe conduction block and temporal dispersion. A sural nerve biopsy revealed remarkable onion bulb-like changes and perivascular infiltration of inflammatory cells. After high-dose corticosteroid treatment, he showed improvement in muscle strength. Although there were no abnormalities of genes related to hereditary neuropathy, the atypical findings of severe demyelinating changes of peripheral nerves mimicked hereditary neuropathy.  相似文献   
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