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991.
992.
Three-dimensional water phantoms are routinely used when acquiring the data necessary to commission medical linear accelerators. A new water phantom controller has been developed at our institution that is unique in several aspects. The water phantom controller is based on an IBM XT compatible computer. This has been interfaced to an Artronix three-dimensional water phantom and a commercially available linac setup controller. Some of the unique features of the new controller are (i) its ability to perform three-dimensional coordinate transformations on the fly (this removes the need to level and align the water tank with the beam axes and greatly reduces setup time). (ii) Its ability to communicate with a device which can control the linac operating parameters (this allows the water phantom controller to adjust, for example, the jaw size of the accelerator as it acquires data). (iii) Its ability to output the acquired data in a number of modes, including screen display, hardcopy plot, or disk file that may be transferred to a central treatment planning computer). (iv) Its ability to digitally process the acquired data. This water phantom controller may be used to gather machine data in a highly automated manner, greatly reducing the time required to gather the desired data.  相似文献   
993.
994.
A radomized study was done in 2 groups of male patients operated upon 3-17 years ago either by partial gastrectomy (Billroth II type) or hermiotomy. The inquiries covered eating, drinking and smoking habits, occupation, body weight, subjective complaints, and use of drugs. Body weight and professional activity after operation were not different in both groups. Gastrectomized patients avoided milk or foods with milk, sweets and legumes more often. Feeling of fullness, vomiting and diarrhea occurred more frequently in gastrectomized subjects, as well as statements about good or even ravenous appetite and thirst. Gastrectomized men, besides, had a higher consumption of alcoholic drinks, preferably of beer.  相似文献   
995.
Introduction of percutaneous drainage (pcd) of subphrenic space in early subphrenic abscesses or fluid collections (e.g. bile) seems to be an alternative to common surgical treatment, if the indication is restricted to single contaminated abscesses. Septicemia, continued contamination, hematomas and multiple abscesses are contraindications. Method: A modified angiocatheter is placed directly or by a Seldinger technique. Adjunct antibiotic treatment is important. The advantages of subphrenic pcd are: simple low risk procedure in local anesthesia, rapid improvement of associated respiratory symptoms, no further contamination of the abdomen. 4 of 6 patients were treated successfully by this procedure.  相似文献   
996.
997.
998.
CASE REPORT. After uneventful induction of general anesthesia, severe hypotension and cardiac arrest developed in a 39-year-old, non-atopic man following infusion of 20% mannitol 80 min after the beginning of anesthesia. It caused a systolic blood pressure of 40 mmHg during a period of 10 min and tachycardia followed by ventricular fibrillation. Immediate resuscitation measures, i.e., external cardiac compression, rapid infusion of 3,000 ml crystalloid and 1,000 ml colloid, central-venous application of suprarenin (2.4 mg total), lidocaine (100 mg), sodium bicarbonate (100 mmol), and two defibrillations, could alleviate the life-threatening reaction. The patient recovered a few hours later without any further sequelae. ALLERGOLOGIC INVESTIGATIONS. Allergologic studies with all drugs involved revealed a positive and specific reaction in an intradermal skin test to 1:100 diluted mannitol, as did in-vitro leucocyte histamine release to 20% and 2% mannitol. For all the other drugs, skin tests and leucocyte histamine release were negative or unspecific. Available RAST determinations to thiopental and suxamethonium were also negative. The total IgE level was normal. CONCLUSIONS. Reflecting the hypotension induced by histamine, the hematocrit rose from 0.4 to 0.5 even though the patient received a large amount of fluid before and during resuscitation. This can be explained by marked sequestration of plasma in the interstitial compartment, leading to hypovolemia. The clinical course and test results suggest that mannitol was the agent responsible for the anaphylactoid reaction.  相似文献   
999.
Seizures in the newborn are a distinctive sign of underlying disease. Different convulsive patterns are described. The most common neurologic syndrome consists of subtle seizures. The most important cause is ischemic encephalopathy. Hypocalcemia is the main metabolic disease. Hypoglycemia seems not to be of special relevance for pathogenesis of newborn seizures. Other episodic symptoms of non-epileptic origin should be considered in the differential diagnosis. It is critical to diagnose the cause and to treat it, since the prognosis depends on the underlying disturbance. Phenobarbital is the anticonvulsive drug of first choice. Duration of treatment is determinated of an preexisting brain damage. Newborns with normal neurological evaluation don't need any longer anticonvulsive treatment after cessation of seizures. The EEG is an important prognostic tool.  相似文献   
1000.
We present a case of successful orbital expansion with a tissue expander in 1 patient. This method will be valuable in preventing the facial deformities of anophthalmia and microphthalmia. The method was successful from a technical standpoint because of scleral investment of the expander and because of relative fixation of the expander by passage of the filling tube through the lateral orbital wall. The early experience of this patient confirms our expectations of successful orbital expansion based on the natural history of patients with orbital tumors or congenital glaucoma and on the experimental work of other investigators.  相似文献   
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