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151.
152.
Ileocecal Tuberculosis   总被引:1,自引:0,他引:1  
Three cases of ileocecal tuberculosis are presented with a review of pathogenesis, diagnosis and therapy.
Emphasis is placed upon preoperative suspicion and the indications for resectional surgery in combination with antituberculous drugs in the management of the patients.  相似文献   
153.
The levels of four acid hydrolases, beta-N-acetyl glucosaminidase, beta- glucuronidase, beta-galactosidase, and acid phosphatase, and the extent of their release (release II) by thrombin was determined in platelets from nine normal subjects, nine patients with storage pool disease, and in normal platelets which had been exposed to aspirin. The levels of all four hydrolases were normal in patients with SPD. However, release of three of these hydrolases (acid phosphatase was an exception) by low concentrations of thrombin (0.015 and 0.04 U/ml) was decreased in the patients as a group, although considerable variation in the extent of release of each enzyme was noted. In contrast, aspirin failed to inhibit release II in normal platelets (except for a slight impairment in the release of beta-N-acetyl glucosaminidase), although release I (serotonin, ATP and ADP) was inhibited. All release defects could be overcome by using higher concentrations of thrombin (0.2 U/ml). The normal levels of acid hydrolases in the platelets of patients with SPD (who are deficient in the platelet dense granules) suggest that these enzymes are not normally stored in the dense granules, but rather in alpha-granules. The findings also support the conclusions of previous studies that the release reaction is impaired in SPD. This release defect appears to be different from that seen in normal platelets after exposure to aspirin.  相似文献   
154.
1. The recognition of the role of insulin resistance in disease states and the recent development of new drugs that modify insulin-dependent metabolism has led to increased use of the euglycaemic hyperinsulinaemic clamp to measure in vivo insulin sensitivity, but several key aspects of the technique are poorly documented in the literature. 2. We have evaluated the reproducibility and intersubject variation of measurements of insulin sensitivity in groups of insulin-sensitive and insulin-resistant subjects and assessed the effects of hand warming on haemodynamic and metabolic responses. 3. Subjects participated in one of two protocols: (i) 18 healthy male volunteers and 18 patients with hypertension and glucose intolerance were clamped on two occasions, 1 week apart with measurements of insulin sensitivity (M) derived after 120 and 180 min of hyperinsulinaemia; and (ii) six healthy volunteers were clamped on one occasion with simultaneous sampling of antecubital and ‘arterialized’ (dorsal hand) venous blood for comparison of plasma glucose concentrations and oxygen saturation and a further six volunteers were clamped on two occasions with and without the use of hand warming. 4. Measurements of M derived after 120 min (M120) and 180 min (M180) of hyperinsulinaemia were reproducible: the coefficients of repeatability (mg/kg per min) of M120 and M180 were 1.0 and 0.9 for volunteers and 1.0 and 1.0 for the patient group, respectively. The intersubject variation in insulin stimulus was high: coefficients of variation for M180 were 22% for volunteers compared with 38% for the patient group. In volunteers compared with the patient group, hand warming significantly increased venous oxygen saturations (95 ± 2 vs 79 ± 18%, respectively) and glucose concentrations (5.2 ± 0.2 vs 4.5 ± 0.4 mmol/L, respectively) and measurements of M were significantly higher using arterialized compared with antecubital venous blood. However, local hand warming was associated with systemic vasodilatation: blood pressure decreased (e.g. 6mmHg diastolic; P < 0.05) with a compensatory increase in heart rate (8 b.p.m.). 5. In conclusion, clamps of 120 and 180 min duration yielded measurements of M that were reproducible. The technique is much more robust when used in the context of a crossover design because of the significant (20–40%) intersubject variation in M, even among apparently homogeneous male volunteers. Hand warming effectively arterializes venous blood and gives significantly higher M values, but induces systemic vasodilatation, which may confound measurements of M.  相似文献   
155.
156.
Calcium-binding proteins such as calretinin are abundantly expressed in distinctive patterns in the CNS, but their physiological function remains poorly understood. Calretinin is expressed in cerebellar granule cells, which provide the major excitatory input to Purkinje cells through parallel fibers. Calretinin-deficient mice exhibit dramatic alterations in motor coordination and Purkinje cell firing recorded in vivo through unknown mechanisms. In the present study, we used patch-clamp recording techniques in acute slice preparation to investigate the effect of a null mutation of the calretinin gene on the intrinsic electroresponsiveness of cerebellar granule cells at a mature developmental stage. Calretinin-deficient granule cells exhibit faster action potentials and generate repetitive spike discharge showing an enhanced frequency increase with injected currents. These alterations disappear when 0.15 mm of the exogenous fast-calcium buffer BAPTA is infused in the cytosol to restore the calcium-buffering capacity. A proposed mathematical model demonstrates that the observed alterations of granule cell excitability can be explained by a decreased cytosolic calcium-buffering capacity resulting from the absence of calretinin. This result suggests that calcium-binding proteins modulate intrinsic neuronal excitability and may therefore play a role in information processing in the CNS.  相似文献   
157.
This study presents a technique to correct kinking or coiling of the internal carotid artery using patch angioplasty following endarterectomy, resection, and anastomoses of the vessel. Since 1984, 579 carotid endarterectomies have been performed with 19 patients (3.3%) having arteriosclerotic carotid bulb and internal carotid artery disease associated with a carotid kink or coil. These have been treated successfully using the technique of resection and patch angioplasty. The indications for surgery included seven patients with transient ischemic attacks (36.8%); seven patients who had suffered a cerebrovascular accident (36.8%); amaurosis fugax in two patients (10.5%); and one patient each with Hollenhorst plaque (5.3%), central retinal artery occlusion (5.3%), and an asymptomatic critical stenosis (5.3%). All patients had successful repair of the vessel using saphenous vein or Dacron patch angioplasty. There were no perioperative strokes or deaths. Follow-up ranged from four months to 58 months (mean 25 months). All vessels are patent with no evidence of stenosis. One patient had an ipsilateral cerebrovascular accident but had no evidence of recurrent carotid disease. Surgical correction of the carotid kink or coil can present a difficult surgical problem, and resection, fixation, or transposition can be complicated. The technique of endarterectomy, resection of the redundant vessel with anastomosis of the back wail, and patch angioplasty has been used effectively and safely in this series of patients.Presented at the Fifteenth Annual Meeting of the Peripheral Vascular Surgery Society, June 2, 1990, Los Angeles, California.The views and opinions expressed in this paper are those of the authors and do not reflect those of the Department of the Army, Department of Defense, or of the Uniformed Services University of the Health Sciences.  相似文献   
158.
Elongated Styloid Process (Eagle''s Syndrome) Causing Hemicrania   总被引:1,自引:0,他引:1  
E. Wayne Massey  M.D.  CDR  USNR  MC  Janice Massey  M.D. 《Headache》1979,19(6):339-344
SYNOPSIS
Hemifacial pain and hemicrania can be caused by an elongated styloid process (Eagle's syndrome). This entity is reviewed historically with six case histories and x–rays presented. The etiology of the symptom complex is unclear, but possible mechanisms such as cranial nerve pressure and carotid sympathetic nerve involvement are discussed. Specific treatment is surgical removal of the tip of the styloid process.  相似文献   
159.
BACKGROUND: Fresh-frozen plasma (FFP) has generally been regarded as an acellular component. Recently, viable lymphocytes have been detected in this component and the question of irradiation of FFP for certain patients has been raised. Whether the numbers of white cells (WBCs) in FFP are sufficient to require WBC-reduction of acellular components for patients receiving WBC-reduced cellular components has not been determined. WBC numbers in FFP were examined, and the performance of a new commercial WBC-reduction filter for FFP was assessed. STUDY DESIGN AND METHODS: WBC numbers in plasma processed for use as FFP and in thawed FFP were counted before and after WBC-reduction filtration by the use of flow cytometry Fast and slow filtration was used to simulate laboratory and bedside filtration, respectively. Three different methods for plasma harvesting (soft-spin, hard-spin, and second-spin methods) were assessed. The filter capacity was also examined. RESULTS: The numbers of WBCs in plasma covered a three-log10 range (soft-spin method, 0.04-3.6 × 10(6); hard-spin method, 0.47-45.4 × 10(6); second- spin method, 0.4–37.2 × 10(6)). For the hard-spin and second-spin methods which produced the greatest plasma yields, 92 percent and 85.7 percent of bags, respectively, had counts>1 × 10(6) and 43 percent (hard-spin method) and 45.7 percent (second-spin method) had counts>5 × 10(6). There was no significant difference between the counts obtained in plasma and thawed FFP. The filter reduced WBC numbers to <1 × 10(5) in all but 3 of 49 bags. In the remaining three, there were <2 × 10(5) WBCs. Five bags of plasma could be processed effectively through each filter. CONCLUSION: FFP may contain WBC numbers above the threshold at which the use of WBC-reduction filters for cellular components in some patients is necessary. Confirmation of these findings and similar investigations on plasma prepared by other methods may help in defining a role for the use of WBC-reduction filters for FFP  相似文献   
160.
Summary We report the case of a 52-year-old white male who developed low back pain and 35-pound weight loss and whose barium enema revealed a constricting lesion of the cecum. After resection, polyarteritis was found to be the cause of the lesion. There was no other histological evidence for arteritis in this patient.The opinions expressed herein are those of the authors and not necessarily those of the Department of Defense, U.S. Air Force, or the Uniformed Services University of the Health Sciences.Figures are published with permission from the Armed Forces Institute of Pathology.  相似文献   
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