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排序方式: 共有8309条查询结果,搜索用时 15 毫秒
91.
Kozo Yoshikawa MD PhD Naoki Hiki MD PhD Tetsu Fukunaga MD PhD Masanori Tokunaga MD Yorimasa Yamamoto MD PhD Akira Miki MD Kyoko Ogawa MD Jun Higashijima MD PhD Shigekazu Ohyama MD PhD Yasuyuki Seto MD PhD Mitsuo Shimada MD PhD Toshiharu Yamaguchi MD PhD 《Journal of the American College of Surgeons》2009,208(6):1045-1050
92.
Kazuhisa Uchiyama Masaki Ueno Satoru Ozawa Shinya Hayami Manabu Kawai Masaji Tani Kazuhiro Mizumoto Masanori Haba Yoshio Hatano Hiroki Yamaue 《Langenbeck's archives of surgery / Deutsche Gesellschaft fur Chirurgie》2009,394(2):243-247
Background and aims Bleeding from the hepatic vein is closely related to central venous pressure (CVP). To evaluate the effect of low central
venous pressure during a hepatectomy, the infrahepatic inferior vena cava (IVC) was half clamped.
Patients and methods Between 2006 and 2007, 20 patients undergoing major hepatectomy with the IVC half clamping (half-clamping group) were compared
with 58 patients undergoing hepatectomy without IVC half clamping between 2003 and 2005 (control group). The types of liver
resection, amount of blood loss during the hepatectomy, volume of blood transfusion, length of hospital stay, and complications
were compared between the two groups.
Results In the half-clamping group, blood loss was decreased in comparison to the control group (p = 0.041) and the suprahepatic CVP was low (2.4 ± 1.8 mmHg; p = 0.0002). The diameter at the root of the right hepatic vein was reduced in comparison to before clamping (5.8 ± 1.6 mm;
p < 0.001). There were no complications of half clamping on any hemodynamic and blood electrolytic parameters.
Conclusion Using the half clamping technique of the IVC, intra-operative CVP was maintained below 3 mmHg without any side effects, and
the low CVP significantly reduced the bleeding from hepatic veins during a major hepatectomy. 相似文献
93.
Masanori Ozaki MS Yusuke Inoue MD PhD Tosiaki Miyati PhD DMSc Hirohumi Hata RT Sinya Mizukami RT Shotaro Komi RT Keiji Matsunaga MD Reiko Woodhams MD PhD 《Journal of magnetic resonance imaging : JMRI》2013,37(1):172-178
Purpose:
To assess the effect of motion artifact reduction on the diffusion‐weighted magnetic resonance imaging (DWI‐MRI) of the liver, we compared velocity‐compensated DWI (VC‐DWI) and VC‐DWI combined with tetrahedral gradients (t‐VC‐DWI) to conventional DWI (c‐DWI) in the assessment of apparent diffusion coefficients (ADCs) of the liver.Materials and Methods:
In 12 healthy volunteers, the liver was scanned with c‐DWI, VC‐DWI, and t‐VC‐DWI sequences. The signal‐to‐noise ratio (SNR) and ADC of the liver parenchyma were measured and compared among sequences.Results:
The image quality was visually better for t‐VC‐DWI than for the others. The SNR for t‐VC‐DWI was significantly higher than that for VC‐DWI (P < 0.05) and comparable to that for c‐DWI. ADCs in both hepatic lobes were significantly lower for t‐VC‐DWI than for c‐DWI (P < 0.01). ADC in the left lobe was significantly lower for VC‐DWI than for c‐DWI (P < 0.01). Although ADC in the left lobe was significantly higher for c‐DWI (P < 0.01), no significant differences in ADCs were found between the right and left lobes for VC‐DWI and t‐VC‐DWI.Conclusion:
The use of a t‐VC‐DWI sequence enables us to correct ADCs of the liver for artificial elevation due to cardiac motion, with preserved SNR. J. Magn. Reson. Imaging 2013;37:172–178. © 2012 Wiley Periodicals, Inc. 相似文献94.
Michael D. Farwell Derek J. Chong Yasuhiko Iida Sung A. Bae Balu Easwaramoorthy Masanori Ichise 《Annals of nuclear medicine》2013,27(7):618-624
Objective
One mechanism that may be responsible for drug resistance in epilepsy is the upregulation of P-glycoprotein (P-gp), a drug efflux pump, at the epileptogenic focus. In this study, we sought to evaluate the potential of a recently developed P-gp PET radiotracer, [11C]N-desmethyl-loperamide ([11C]dLop), for measuring P-gp function in the rat brain.Methods
The precursor to [11C]dLop was synthesized in two steps from commercially available starting materials and subsequently radiolabeled in one step using [11C]methyl iodide. [11C]dLop was then administered to two groups of rats, controls (n = 4) and those treated with a P-gp inhibitor (n = 8). Cyclosporin A (CsA, 50 mg/kg, n = 3) and tariquidar (TQ, 20 mg/kg, n = 5) were both used as P-gp inhibitors. MicroPET brain scans were performed for 120 min with arterial blood sampling. A one-tissue compartment model was used to estimate the distribution volume of radiotracer as the outcome measure of P-gp function.Results
Plasma levels of parent [11C]dLop decreased rapidly to <0.1 mean standardized uptake value (SUV) at 60 min. In controls, brain uptake of [11C]dLop was very low (<0.1 mean SUV). In contrast, the mean SUVs were significantly higher in rats treated with CsA (0.51) or TQ (0.22). Estimation of distribution volumes was stable by 70 min. Estimated distribution volumes were significantly larger after P-gp inhibition (CsA = 7.3, TQ = 4.7) compared to controls (no inhibitor = 2.1).Conclusions
The rat brain demonstrates significantly increased uptake of [11C]dLop after P-gp inhibition. [11C]dLop is a substrate of P-gp, and will serve as a promising radiotracer for studying P-gp function in the future. 相似文献95.
Poor prognosis after lung resection for patients with adenosquamous carcinoma of the lung 总被引:12,自引:0,他引:12
Nakagawa K Yasumitu T Fukuhara K Shiono H Kikui M 《The Annals of thoracic surgery》2003,75(6):943-1744
BACKGROUND: We evaluated the prognosis of adenosquamous carcinoma of the lung after lung resection in comparison with other types of carcinoma. METHODS: We retrospectively reviewed charts of patients who underwent lung resection for lung cancer. RESULTS: Surgical outcomes for 30 patients with adenosquamous carcinoma of the lung, who were treated between 1976 and 1998, were compared with the surgical results for 1,219 patients similarly treated for adenocarcinoma or squamous cell carcinoma during the same period. Adenosquamous carcinoma comprised only 2.1% of 1,408 lung cancer cases treated by resection. The overall cumulative 5-year survival rate was only 6.2% for the patients with adenosquamous carcinoma, indicating a significantly poorer prognosis than for adenocarcinoma or squamous cell carcinoma. CONCLUSIONS: The cumulative survival rate for patients with adenosquamous carcinoma in pathologic stages IA to IIB was similar to that of patients with stage IIIA adenocarcinoma or squamous cell carcinoma. 相似文献
96.
Magnetic resonance cholangiopancreatography for postoperative follow-up of intraductal papillary-mucinous tumors of the pancreas 总被引:4,自引:0,他引:4
Sugiyama M Abe N Tokuhara M Masaki T Mori T Takahara T Hachiya J Atomi Y 《American journal of surgery》2003,185(3):251-255
BACKGROUND: After resection of an intraductal papillary-mucinous tumor (IPMT), benign tumors or portions of the resected tumor are sometimes left in place to avoid total pancreatectomy. We evaluated the role of magnetic resonance cholangiopancreatography (MRCP) in postoperative follow-up. METHODS: Twenty-two patients underwent MRCP 0.5 to 6.5 years after pancreatic resection for IPMT. RESULTS: Two patients with surgical margin involvement of the main pancreatic duct showed mildly enhanced ductal dilatation due to anastomotic stenosis. In 4 patients with residual IPMT of the branch ducts, postoperative MRCP demonstrated no changes. MRCP revealed new IPMT 1 year after surgery in 1 patient. No patients showed intraductal or intracystic mural nodules postoperatively. In 3 patients with postoperative pancreatitis or recurrent abdominal discomfort, MRCP demonstrated ductal dilatation and poor secretin-stimulated pancreatic secretion into the gastrointestinal tract, which suggested pancreatoenterostomic stenosis. CONCLUSIONS: MRCP is useful for postoperative follow-up of IPMT, in terms of investigating residual or recurrent IPMT and evaluating postpancreatectomy long-term complications. 相似文献
97.
Inoue H Kinoshita K Sugiyama M Funauchi M Hanagama M Nata M 《Medicine, science, and the law》2008,48(3):261-265
Primary Sj?gren syndrome (SjS) has a comparatively good prognosis except when it is complicated by non-Hodgkin's lymphoma. We performed an autopsy on a young female patient with primary SjS who had died suddenly during a meal, and we discuss the relationship between primary SjS and the cause of death. Eosinophilic change of the cardiomyocytes and severe arteriolosclerosis were observed within the myocardium. In the conduction system, lymphocyte infiltration was detected in the bundle of His, in addition to arteriosclerosis in the sinoatrial node and atrioventricular node arteries. The cause of death was diagnosed as ischaemic heart disease induced by arteriolosclerosis: its development can probably be attributed mostly to primary SjS. It should thus be kept in mind that primary SjS can occasionally result in the development of cardiovascular complications, such as ischaemic heart disease, as well as systemic lupus erythematosus or rheumatoid arthritis. 相似文献
98.
Aramaki O Shirasugi N Akiyama Y Shibutani S Takayama T Shimazu M Kitajima M Ikeda Y Okumura K Yagita H Niimi M 《Transplantation》2003,76(5):772-776
BACKGROUND: We investigated whether blockade of tumor necrosis factor receptor-ligand pathways could generate regulatory cells induced by intratracheal delivery of alloantigen. METHODS: CBA (H-2k) mice were pretreated with intratracheal delivery of splenocytes (1x10(7)) from C57BL/10 (H-2b) mice and intraperitoneal administration of monoclonal antibody (mAb) specific for CD70, CD134 ligand (CD134L), CD153, or CD137L. Seven days later, C57BL/10 hearts were transplanted into pretreated CBA mice. Some naive CBA mice underwent adoptive transfer of splenocytes (5x10(7)) from pretreated CBA mice and transplantation of a C57BL/10 heart on the same day. RESULTS: Untreated CBA mice rejected C57BL/10 cardiac grafts acutely (median survival time [MST] 12 days). Pretreatment with intratracheal delivery of C57BL/10 donor splenocytes prolonged graft survival significantly (MST 84 days). Mice given intratracheal delivery of alloantigen plus anti-CD70, anti-CD134L, or anti-CD153 mAb, but not those given intratracheal delivery of alloantigen plus anti-CD137L mAb, rejected their graft acutely (MST 16, 14, 10, and 65 days, respectively). Adoptive transfer of splenocytes from mice pretreated with intratracheal delivery of alloantigen plus anti-CD70, CD134L, or CD153 mAb did not prolong survival of C57BL/10 cardiac grafts in naive secondary CBA recipients (MST 14, 11, and 11 days, respectively), whereas adoptive transfer of splenocytes from mice given intratracheal delivery of alloantigen plus anti-CD137L mAb did (MST 75 days). CONCLUSION: The CD27/CD70, CD134/CD134L, and CD30/CD153 pathways are independently required for generation of regulatory cells in our model. 相似文献
99.
The accuracy of transcutaneous carbon dioxide monitoring during laparoscopic surgery 总被引:8,自引:0,他引:8
Nakamura A Kanai M Mizushima A Katashima S Miura K Kawauchi Y Kamiyama Y 《Masui. The Japanese journal of anesthesiology》2003,52(8):846-851
BACKGROUND: Laparoscopic procedures are considered relatively low-invasive. However, there exists a small but important risk of developing complications related to carbon dioxide (CO2) insufflation. End-tidal CO2 (PetCO2) monitoring may not be a sufficient guide to adjust pulmonary ventilation during laparoscopic surgery, and arterial CO2 (PaCO2) monitoring is not always indicated. We evaluated the accuracy and feasibility of transcutaneous CO2 (PtcCO2) monitoring during laparoscopic surgery. METHODS: Thirty adult patients undergoing abdominal or gynecological laparoscopic surgery were studied. PtcCO2, PaCO2 and PetCO2 were measured before laparoscopy, and 30 and 60 minutes after beginning of CO2 insufflation. PtcCO2 and PaCO2 were also measured in the recovery room under spontaneous respiration. RESULTS: During operation, the PtcCO2 values demonstrated a high degree of correlation with PaCO2 (r = 0.92), and PetCO2 values also demonstrated generally a good correlation with PaCO2 (r = 0.85). The PtcCO2 PaCO2 gradient was -0.6 +/- 2.2 mmHg, while the PetCO2-PaCO2 gradient was -3.9 +/- 2.7 mmHg. In the recovery room, PtcCO2 values still demonstrated a high correlation with PaCO2 (r = 0.91). CONCLUSIONS: The transcutaneous devices provide an effective method for non-invasive monitoring of PCO2 in situations where continuous monitoring of CO2 levels is desired such as peri-operative period of laparoscopic surgery. 相似文献
100.
Tadahiko Masaki Makoto Takayama Hiroyoshi Matsuoka Nobutsugu Abe Hisayo Ueki Masanori Sugiyama Ayako Tonari Junko Kusuda Shinsaku Mizumoto Yutaka Atomi 《Langenbeck's archives of surgery / Deutsche Gesellschaft fur Chirurgie》2008,393(2):173-180
Backgrounds Pelvic autonomic nerve preservation (PANP) with lateral lymph node dissection (LLND) has been introduced in rectal cancer
surgery in Japan; however, its indication has not been standardized yet.
Materials and methods Forty-four patients with advanced lower rectal cancer were randomized to either the standard treatment group (control group)
or the intraoperative radiotherapy (IORT) group. All patients underwent potentially curative resection of the rectum with
total mesorectal excision. The control group underwent bilateral LLND and limited PANP. The IORT group underwent bilateral
LLND, complete PANP, and IORT. Patients allocated to the IORT group received IORT to the bilateral preserved pelvic nerve
plexuses. Patients’ clinicopathologic parameters, postoperative complications, voiding function, and prognosis were compared
between the two groups.
Results Among 44 patients enrolled, three patients were excluded from the analysis, resulting in 19 patients in the IORT group and
22 patients in the control group. Patients’ demographic and pathological parameters and postoperative complications were well
balanced between the two groups. Oncological outcomes including overall and disease-free survival were also similar. Local
recurrence was observed in one patient in each group. Among the 34 patients not complicated with intrapelvic abscess, the
mean duration of urinary catheter indwelling was 8 days in the IORT group and 13 days in the control group (p = 0.055). In the long term, medication for urination was necessitated in four patients in the control group, whereas in none
in the IORT group (p = 0.059).
Discussions Oncological outcomes in the IORT group are equal to those in the control group, and voiding functions in the IORT group are
superior to those in the control group. These results suggest that IORT may be useful to expand the indication of complete
PANP with LLND for advanced lower rectal cancer. 相似文献