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91.
OBJECTIVE: To clarify the position of on-pump beating coronary artery bypass (CAB) and to define preoperative indicators of intentional conversion to the procedure in the era of advancement of off-pump CAB (OPCAB), we assessed on-pump beating CAB performed after the introduction of OPCAB. SUBJECTS AND METHODS: We assessed 130 patients who underwent single CAB [117 (90%) with OPCAB and 13 (10%) with on-pump beating CAB] between August 1999 (when OPCAB was selected as the first-line surgical procedure) and December 2004. RESULTS: No significant differences were seen between the groups in the number of coronary lesions or the prevalence of left main trunk (LMT) lesion. Reduced left cardiac function, cardiac dilatation, and mitral regurgitation (MR) were more remarkable in the on-pump beating CAB group. Preoperative ischemic condition was generally unstable in the both groups. A conversion to on-pump beating CAB occurred at anastomosis for the left anterior descending (LAD) branch in 61% and for the left circumflex (LCX) branch in 15%. LAD patients had more severe left cardiac dysfunction and cardiac dilatation than LCX patients. CONCLUSION: To perform safe and reliable CAB surgery, cardiovascular surgeons should define preoperative indicators of difficult OPCAB and convert OPCAB to on-pump beating CAB intentionally without hesitation when unstable hemodynamics is detected.  相似文献   
92.
The enhancing effect of combining 1-methyl-2-pyrrolidone (MP) and 1-lauryl-2-pyrrolidone (LP) as the vehicles for transdermal penetration of phenolsulphonphthalein (phenol red) has been investigated by using an in-vitro technique with excised rat skin. LP had a higher enhancing effect on the penetration of phenol red than MP, but there was a long lag time before steady-state penetration was attained. A potent effect with a shorter lag time was obtained when MP and LP were used together. This potentiation was maintained when the concentration of MP was decreased by 95%. The combined vehicle also enhanced the skin accumulation of phenol red. MP promoted the rapid penetration of LP into the skin and potentiated the enhancing effect of LP on the penetration of phenol red and thereby shortened the lag time. The combined vehicle also enhanced the penetration of the hydrophilic anticancer agent, 5-fluorouracil.  相似文献   
93.
The cecal foramen pointer was invented for a Sistrunk median cervical cyst operation. The instrument consists of three elements, namely: The cecal foramen holder, the giraffe shaped connector and the pointer needle. First of all, the cecal foramen is held by the holder which is reconstructed from hemostatic forceps. The one end of the connector is joined to the holder's handle. Then the other end of the connector comes along the patient's chin, in front of the neck. The cyst and mid-portion of the hyoid bone are dissected, followed by coring out of the thyroglossal duct toward the cecal foramen. In the coring out process, the pointer needle is pierced through the tunnel of the connector's opposite end, so that the needle top reaches to the bottom of operative wound. Then the needle shows exactly the direction to the cecal foramen and the distance from the bottom of the wound to the cecal foramen. By using this instrument the operation was successfully performed for a case of a recurrent median cervical cyst with a complete fistula to the cecal foramen.  相似文献   
94.
1. Sensory mechanisms play an important role in the vagal regulation of tracheobronchial smooth muscle tone. We examined the effect of KW-4679, an anti-allergic drug, on guinea-pig tachykinin-mediated contractile responses induced by electrical field stimulation (EFS) in guinea-pig bronchial muscles. 2. EFS (8 Hz, 0.5 ms, 15 V, for 15 s) evoked biphasic contractile responses in the guinea-pig isolated main bronchus in the presence of 5 microM indomethacin. The contractions consisted of a fast phase of an atropine-sensitive transient contraction and a slow phase of a sustained contraction which was inhibited by a combination of the tachykinin NK1 receptor antagonist, (+/-)-CP-96,345 (1 microM) and the NK2 receptor antagonist, SR 48969 (0.1 microM). 3. KW-4679 preferentially inhibited the slow phase in a concentration-dependent manner by 43.2 +/- 7.7% at 10 microM, whereas the drug had no effect on the fast phase at concentrations up to 10 microM. KW-4679, at a concentration of 100 microM, inhibited not only the slow phase by 49.2 +/- 11.4%, but also the fast phase by 36.8 +/- 9.3% [corrected]. 4. KW-4679 (10 microM and 100 microM) did not affect the substance P-induced or neurokinin A-induced contraction. Against the acetylcholine-induced contractile responses, 100 microM KW-4679 had a marked effect producing a 10.2 fold shift to the right in the curve. 5. The inhibitory effect of KW-4679 (10 microM) on the slow phase contraction was not influenced by treatment with naloxone (100 nM), propranolol (1 microM), thioperamide (1 microM), saclofen (50 microM), yohimbine (1 microM), methiothepin (1 microM) or methysergide (1 microM). 6. The inhibitory effect of KW-4679 (10 microM) on the slow phase contraction was not influenced by treatment with intermediate or large conductance Ca(2+)-activated K+ channel blockers (charybdotoxin (10 nM) or iberiotoxin (10 nM)), but suppressed by treatment with small conductance Ca(2+)-activated K+ channel blockers, apamin (500 nM) or scyllatoxin (300 nM). Apamin or scyllatoxin per se did not influence the slow phase contractions. 7. The results suggest that KW-4679 preferentially inhibits the release of tachykinins from the bronchial sensory nerves through activation of small conductance Ca(2+)-activated K+ channels.  相似文献   
95.
Previously, we demonstrated that the inductive properties of bone morphogenetic protein (BMP) highly depend on the nature of the carrier material used for implantation. In this paper, we show that administration of BMP incorporated in a fibrous collagen membrane can help to regenerate periodontal ligament and cementum both in cat canines and in monkey molars. The partially purified bovine BMP was combined with one or two layers of a fibrous collagen membrane. Although the single layer approach showed partial regeneration of periodontal defects, it also quite often led to ankylosis. The double layer technique in artificially prepared class III furcation defects in monkey molars gave favorable results. After 12 wk, not only the alveolar process but also the periodontal ligament and cementum had regenerated along the entire treated dentin surface. Collagen fibers were arranged more or less perpendicular to the surface of the new cementum. Ankylosis was not seen. It is concluded that the double-layer approach is superior to the single-layer technique in regenerating cementum.  相似文献   
96.
A human chromosomal translocation t(8;9) was detected using two-color fluorescence in situ hybridization with probes capable of staining the entire lengths of each of these chromosomes. The chromosome 8 probe was labeled with biotin and detected with Texas red, while the chromosome 9 probe was labeled with AAF and detected with FITC . In normal metaphase spreads, two metaphases from the proband, two red, one green and one part red and part green derivative chromosome were seen. The bicolor chromosome corresponded to translocation of a chromosome 8 segment to the distal part of the q region of one chromosome 9, as originally indicated by banding analysis. In interphase nuclei of the proband, four domains with bright fluorescence were recognized in many nuclei. Two were red, one was green, and the fourth had portions of both colors, indicating the presence of the translocation.  相似文献   
97.
The PCNA score was measured in oral squamous cell carcinoma (SCC), and its relationship to other cell proliferation markers, Ki-67 score, S-phase fraction (SPF), and AgNORs counts was investigated. The PCNA score ranged from 0.4% to 43.5% with an average value of 22.8%, the Ki-67 score ranged from 4.9% to 40% with an average of 24.1%, and the SPF ranged from 0.4% to 32.5% with an average of 12.4%, while AgNORs counts ranged from 2.53/nucleus to 7.03/nucleus with an average of 4.74/nucleus. These four parameters were closely interrelated. There was a significant difference in PCNA score between malignant and nonmalignant lesions, suggesting a difference in growth activity. The mean PCNA score decreased significantly from 20.0% to 8.0% after cancer chemotherapy. The response of cancer cells to anticancer agents may be estimated by consecutive measurement of PCNA, since the PCNA score dropped after treatment in cases showing a favorable prognosis.  相似文献   
98.
99.
An ultrastructural study was undertaken concerning morphological changes within the autografted patellar tendon (PT) after being transplanted to the anterior cruciate ligament (ACL) in mongrel dogs. After 4 weeks, the arrangements of both large and small collagen fibrils in the PT graft became disordered, and the number of inflammatory cells increased. However, the same PT grafts revealed postsurgical signs of newly-produced collagen fibrils around activated fibroblasts at 12 to 24 weeks. At 52 weeks after the transplantation, small collagen fibrils increased in both number and density, showing a remarkable morphological similarity to the collagen fibrils of normal ACL. These data indicate that the characteristics of the PT graft eventually resemble those of a normal ACL. This paper was presented in part at the Combined Meeting of the Orthopedic Research Societies of the USA, Japan and Canada in Banff, Alberta, Canada, October, 1991.  相似文献   
100.
The antitumor effects of 2'-C-cyano-2'-deoxy-1-beta-D- arabinofuranosylcytosine (CN-DAC), a synthetic 1-beta-D-arabinofuranosyl-cytosine (ara-C) derivative, were examined and compared with that of ara-C in murine tumors and in various human tumors using three different chemosensitivity tests. CNDAC extended the life span of mice bearing P388 leukemia. CNDAC had a unique in vitro antitumor spectrum for human cancers different from that of ara-C. Compared with ara-C, CNDAC was more effective in 10 human tumors (2 lung, 4 stomach and 4 osteosarcoma), equal in 2 tumors (lung and fibrosarcoma) and less potent in 11 tumors (4 lung, 4 osteosarcoma, bladder, renal and epidermoid). Characteristically CNDAC showed excellent activities against tumors, refractory to ara-C, such as HT-1080 human fibrosarcoma implanted in chick embryos or athymic mice, although its cytotoxicity against HT-1080 was almost equal to that of ara-C. Thus, CNDAC is an interesting and promising agent that should be considered for further detailed preclinical evaluation.  相似文献   
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