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Endoscopic nasobiliary drainage (ENBD) is a well established mode of biliary decompression. Although ENBD is certainly an uncomfortable procedure with the potential risk of spontaneous dislocation or removal of the drainage catheter by disoriented patients, it has several advantages over endoscopic biliary drainage (EBD) using an indwelling stent. The current indications for ENBD are: (i) temporary drainage to treat obstructive jaundice and cholangitis caused by malignant or benign biliary stricture; (ii) urgent drainage to treat suppurative cholangitis primarily caused by common bile duct stones; (iii) temporary drainage after stone removal in patients with suspected incomplete clearance and/or with cholangitis; and (iv) biliary leaks that occur primarily after surgery, as well as other indications. Different types of nasobiliary catheters are currently available that have been designed with various diameters, shapes, and materials. However, the current catheters are not considered by most endoscopists to be sufficient. Further improvements are needed to achieve better drainage and better maneuverability.  相似文献   
3.
We tested the hypothesis that premedication with i.m. midazolam decreases core temperature dose-dependently. We studied six male volunteers, in random order, on 3 days: (1) no midazolam administration (control day), (2) midazolam 0.025 mg kg-1 i.m., (3) midazolam 0.075 mg kg-1 i.m. On the first day, subjects were maintained alert during a 30- min control period. On the second and third days, midazolam 0.025 or 0.075 mg kg-1 was administered i.m. Core temperatures were measured at the right tympanic membrane. Four adhesive skin surface probes were fixed on the chest, upper right arm, lateral calf and thigh. Finger tip perfusion was evaluated using forearm minus fingertip and calf minus toe, skin surface temperature gradients. Thirty minutes after midazolam i.m., the level of sedation in the volunteers was assessed. Peripheral venous blood was obtained immediately after the assessment of the level of sedation. Tympanic membrane temperatures after administration of midazolam 0.075 mg kg-1 i.m. were significantly lower than those on the control and midazolam 0.025 mg kg-1 i.m. days at 20 and 30 min. The decreases in tympanic membrane temperatures at 30 min after midazolam i.m. became larger as the volunteers were more deeply sedated. i.m. midazolam produced a concentration-dependent decrease in tympanic membrane temperature at 30 min after midazolam 0.025 and 0.075 mg kg-1 i.m. We conclude that midazolam impaired tonic thermoregulatory vasoconstriction, allowing core-to-peripheral heat redistribution in a dose-dependent manner after i.m. administration.   相似文献   
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To control intraoperative bleeding is an important key to successful endoscopic submucosal dissection. The distribution of submucosal vessels encountered during the procedure differ in places in the stomach and are roughly categorized into three groups: those located in the antrum, those in the lesser curvature, and those on the anteroposterior corpus wall which consists of oblique muscle layers. Therefore, knowledge of a suitable setting of diathermy and adjusted depth of dissection in the submucosal layer for each site is imperative. The combination of utilizing the distal attachment forced or swift coagulation (trimming with coagulation mode) have enable the treatment with an insulation tipped knife safer.  相似文献   
6.
Background: Anesthetics inhibit airway smooth muscle contraction in part by a direct effect on the smooth muscle cell. This study tested the hypothesis that the anesthetics halothane and hexanol, which both relax airway smooth muscle in vitro, inhibit acetylcholine-promoted nucleotide exchange at the [alpha] subunit of the Gq/11 heterotrimeric G protein (G[alpha]q/11; i.e., they inhibit muscarinic receptor-G[alpha]q/11 coupling).

Methods: The effect of halothane (0.38 +/- 0.02 mm) and hexanol (10 mm) on basal and acetylcholine-stimulated G[alpha]q/11 guanosine nucleotide exchange was determined in membranes prepared from porcine tracheal smooth muscle. The nonhydrolyzable, radioactive form of guanosine-5'-triphosphate, [35S]GTP[gamma]S, was used as the reporter for G[alpha]q/11 subunit dissociation from the membrane to soluble fraction, which was immunoprecipitated with rabbit polyclonal anti-G[alpha]q/11 antiserum.

Results: Acetylcholine caused a significant time- and concentration-dependent increase in the magnitude of G[alpha]q/11 nucleotide exchange compared with basal values (i.e., without acetylcholine), reaching a maximal difference at 100 [mu]m (35.9 +/- 2.9 vs. 9.8 +/- 1.2 fmol/mg protein, respectively). Whereas neither anesthetic had an effect on basal G[alpha]q/11 nucleotide exchange, both halothane and hexanol significantly inhibited the increase in G[alpha]q/11 nucleotide exchange produced by 30 [mu]m acetylcholine (by 59% and 68%, respectively).  相似文献   

7.
The gastric vasculature responsible for intraoperative bleeding in endosocpic submucosal dissection (ESD) is the ramified vascular network occupying the middle of the submucosal layer and large vessels penetrating the muscle layer. Appropriate management for these vessels must be addressed. The trimming of the ramified vascular network can be safely performed with coagulation mode following shallow mucosal cutting. A large penetrating vessel usually requires precoagulation prior to dissection. These procedures are effectively performed with the water jet short needle knife (Flush knife).  相似文献   
8.
A patient with cerebral deep sinus thrombosis, which was not diagnosed on the first examination, is reported. A 46-year-old woman presented with headache and vomiting. Neurological examination and a brain computed tomography (CT) scan showed no obvious abnormal findings. The patient suffered disturbed consciousness on the day after the examination, and was admitted to our emergency centre. A CT scan and magnetic resonance imaging revealed an ischaemic lesion in the left basal ganglia, suggesting deep sinus occlusion. Anticoagulant therapy was administered. One day after admission, a CT scan showed a haematoma and severe brain swelling in the same region. Cerebral angiography demonstrated a straight sinus occlusion. Intracranial pressure was not controlled with hypothermia, and the patient died 25 days after admission. Review of the initial CT scan revealed subtle, early findings of deep venous thrombosis that were missed on first examination.  相似文献   
9.
Progressive multifocal leukoencephalopathy (PML) is a fetal demyelinating disease in the central nervous system. PML was once a rare disease, but it is now relatively common among AIDS (acquired immunodeficiency syndrome) patients. The immunological state of patients mainly contributes to the pathogenesis of PML. Genetic changes of the etiological agent, however, may also be involved in the development and progression of the disease. The major genetic changes possibly associated with PML include the regulatory region rearrangement and the VP1 loop mutation. Both changes have been identified as genetic changes usually occurring in JCV (JCvirus) DNAs from the brain and cerebrospinal fluid of PML patients. Although it remained to be clarified how these changes are involved in the pathogenesis of PML, accumulating evidence suggests that the VP1 loop mutation is associated with the progression of PML. Here we overview studies (mainly those performed by ourselves) on these genetic changes.  相似文献   
10.
We evaluated the effects of rowing on the morphology and function of the leg extensor muscle in old people. The area and the power of the leg extensor muscle were measured in 15 oarsmen – age [mean (SD)] 65 (3) years; height 171 (4) cm, body mass 68 (6) kg – and in 15 sedentary men – age 66 (4) years, height 170 (4) cm, body mass 67 (7) kg – who were matched on the basis of their body size. The leg extensor muscle area of the oarsmen was larger than that of the sedentary men [77.8 (5.4) vs 68.4 (5.1) cm2, P<0.05]. Also the bilateral leg extension power of the oarsmen was larger than that of the sedentary men [1,624 (217) vs 1,296 (232) W, P<0.05]. Thus, the leg extension power per the leg extensor muscle area was not significantly different between two groups [20.9 (2.0) vs 19.9 (2.1) W·cm–2) and leg extension power was correlated to the leg extensor muscle area (59–89 cm2, r=0.74, P<0.001). Also the 2,000-m rowing ergometer time of the oarsmen [495 (14) s; range 479–520 s] was related to leg extensor muscle area (68–89 cm2, r=0.63, P<0.01). The results suggest that rowing prevents age-related muscle wasting and weakness. Electronic Publication  相似文献   
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