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症例は89歳，男性．徐々に増悪する下腹部痛を主訴に来院．CTにて内部に粗大な石灰化を伴う最大径約13cmの限局性腸管拡張を認めた．当初はMeckel憩室炎を疑い，手術を施行した．開腹時所見にて既往の手術（昭和36年に寄生虫による腸閉塞にて小腸部分切除）における吻合部肛門側腸管の嚢腫状拡張が見られた．さらに拡張腸管内には径4cm大の腸石を3個認めた．結石成分分析を行い，腸石は蓚酸カルシウムを主成分とする真性腸石と判明した．真性腸石は本邦ではこれまでに46例の報告を認めるのみで，比較的稀な疾患である．また本症例では，吻合部の肛門側腸管の嚢腫状拡張を認めるという特異な形態を呈していたため，これについても若干の考察を加えて報告する．

100 TW light from the Petawatt Module (PWM) laser illuminated a preimploded spherical deuterated polystyrene(CD) shell target. The DD neutron yield increased from 2.5×105–106. Analysis indicates that hundreds of keV deuterons, generated around the critical density, collide with cold fuel deuterons and play the leading role in the enhancement of the neutron yield. A two-dimensional particle-in-cell (2D PIC) simulation predicted well the deuteron spectrum. A 60 TW laser was used for MeV proton emissions and megagauss magnetic fields generation on the rear surface of a Poly p-xylene(C8H8) plane target. The 2D PIC simulation explained well the results. The PWM laser was upgraded to one PW, making it the world biggest Petawatt laser (PW laser). An optically parametric chirped amplification was introduced in the front end. The pulse was synchronized to the GEKKO XII imploding beams to within 10 ps.

A 54-year-old man underwent distal gastrectomy for early gastric cancer in September 2002. CT performed 6 months after the operation revealed liver metastases, and they were resected. Hepatic arterial infusion therapy of 5-FU was performed; however, multiple liver metastases appeared in October 2003. We added arterial infusion of CDDP to 5-FU, but liver metastases increased. We then applied a combination chemotherapy of S-1 and paclitaxel from February 2004. Subsequently, stable disease continued, and after 67 courses of S-1 plus paclitaxel, we changed the administration to S-1 alone from August 2009. After that, liver metastases did not increase, so we discontinued chemotherapy on August 2010, followed by observation. Progression of liver metastases has not been to date.

A uniformly imploded deuterated polystyrene (CD) shell target is fast-heated by a Petawatt (PW) laser without cone guide. The best illumination timing is found to be in a narrow region around 80+/-20 picoseconds from the onset of the stagnation phase, where thermal neutrons are enhanced four to five times by the PW laser of energy less than 10% of the implosion laser. The timing agrees with the timings of enhancement of the x-ray emission from the core and reduction of the bremsstrahlung radiation from scattered hot electrons. The PW laser, focused to the critical density point, generates the energetic electrons within as narrow an angle as 30 degrees , which then heats the imploded CD shell to enhance thermal neutrons. These results first demonstrate that the PW laser directly heats the imploded core without any conelike laser guide.

An ultraintense laser injected a 10 J of power at $1.053\text{ }\ensuremath{\mu}\mathrm{m}$ in 0.5 ps into a glass capillary of 1 cm long and $60\text{ }\ensuremath{\mu}\mathrm{m}$ in diameter and accelerated plasma electrons to 100 MeV. One- and two-dimensional particle codes describe wakefields with $10\text{ }\text{ }\mathrm{GV}/\mathrm{m}$ gradient excited behind the laser pulse, which are guided by a plasma density channel far beyond the Rayleigh range. The blueshift of the laser spectrum supports that a plasma of ${10}^{16}\text{ }{\mathrm{cm}}^{\ensuremath{-}3}$ is inside the capillary. A bump at the high energy tail suggests the electron trapping in the wakefield.

A 25 J −1.053 μm pulse in 0.45 ps (a0= 2.2) was injected into a gas jet. This excited a large amplitude self‐modulated wakefield. By increasing the pulse length from 0.45 to to 1.2 ps, the wakefield grew close to the wave‐breaking limit, which sustained a 350 ± 150 GV/m acceleration field over a 1 mm dephasing distance along the laser axis in a plasma with density 2 × 1019 cm−3. This resulted in electrons accelerated to 300 MeV. The amplitude saturation of the wakefield is explained by a pump depletion effect to the large amplitude forward Raman instability. The Petawatt Laser is completed, which will be used to accelerate electrons above one GeV.

To demonstrate the feasibility of the fast ignitor scheme, the 100 TW Petawatt Module laser PWM was illuminated on an imploded spherical CD shell, which enhanced neutron yield ~106 for the first time. This is due to the fusion reactions between the energetic deuteron beam and cold dense deuterons. Without PWM, we have observed no neutrons above the detection threshold ~105. Proton rear emission and possible gigagauss scale magnetic fields from 60 TW laser illuminated plastic target are observed in a good agreement with a two-dimensional PIC simulation. The PWM is up graded to the world biggest Petawatt Laser (say PW laser). The out put is 1 Petawatt, which is used also for ultra-intense laser matter interactions above the intensity of 1020 W/cm2.© (2001) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.