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951.
One thousand three hundred and sixteen consecutively catheterized infants and children were evaluated prospectively for femoral artery thrombosis following percutaneous cardiac catheterization. One hundred units/kg heparin bolus was given to 649 patients after arterial puncture (group A). A supplementary 50 units/kg of heparin bolus was given to 381 patients 75 minutes later, followed by a continuous heparin infusion if pulses were decreased (group B). Two hundred forty-one patients were managed similarly except the first supplementary bolus was given 45 minutes after initial heparinization, if necessary, and the second bolus and continuous infusion were begun 45 minutes later, if necessary (group C). Arterial thrombosis was diagnosed if pulses were not equal to those of the unused extremity 6 hours following catheterization. The overall incidence of arterial thrombosis was 0.8%. No statistically significant (p less than .05) differences occurred related to the heparinization method used. However, absence of thrombosis in the last 241 consecutive patients (group C) and in the last 480 patients of groups B and C weighing more than 10 kg approaches significance (p less than .1). Incidence of thrombosis was less than in previous studies (p less than .0005 to .05). This study indicates that a very low incidence of arterial thrombosis can be achieved with systemic heparinization.  相似文献   
952.
Tissue gain and efficiency and carcass characteristics of seventy-eight Angus steers were compared on three feed intake regimens and serially slaughtered at 6 months to 6 years. The regimens were: (A) continuous ad ad libitum feeding, (B) restricted to gain about 0.45 kg daily and (C) restricted as in B until 6 months before slaughter then fed ad libitum. Steers, regardless of feeding regimen, made their greatest gains up to 12 months of age and became less efficient after that time. Steers fed ad libitum had the highest percentage of fat but the lowest percentage of lean and bone when compared with steers fed for restricted gain. Carcasses of the steers fed ad libitum contained more lean and fat at each slaughter age. Average daily gain, feed efficiency and percentage of lean and bone decreased with age; and feed intake, slaughter grade, dressing percent, taste panel desirability and percent of fat tended to increase with age. All steers reached their maximum growth in height at withers, depth of chest and length of body at about 3 years. Steers that were restricted up to 6 months before slaughter showed compensatory growth during their ad libitum feeding period and during the first 12 months of the study; protein and fat were produced most efficiently by this growth. It would appear that it is possible to modify fat deposition by changing feed intake level.  相似文献   
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OBJECTIVE: Tuberculosis (TB) can no longer be considered a rare disease in the United States due, in part, to the AIDS epidemic. Because the signs and symptoms of intestinal TB are nonspecific, a high index of suspicion must be maintained to ensure a timely diagnosis. The aim of this article is to review the history, epidemiology, pathophysiology, and treatment of TB. METHODS: This review is based on an examination of the world literature. RESULTS: In only 20% of TB patients is there associated active pulmonary TB. Areas most commonly affected are the jejunoileum and ileocecum, which comprise >75% of gastrointestinal TB sites. Diagnosis requires colonoscopy with multiple biopsies at the ulcer margins and tissue sent for routine histology, smear, and culture. If intestinal TB is suspected, empiric treatment is warranted despite negative histology, smear, and culture results. Treatment is medical, and all patients should receive a full course of antituberculous chemotherapy. Exploratory laparotomy is necessary if the diagnosis is in doubt, in cases in which there is concern about a neoplasm, or for complications that include perforation, obstruction, hemorrhage, or fistulization. CONCLUSIONS: This review draws attention to the resurgence of tuberculosis in the United States. An increased awareness of intestinal tuberculosis, coupled with knowledge of the pathophysiology, diagnostic methods, and treatment should increase the number of cases diagnosed, thus improving the outcome for patients with this disease.  相似文献   
956.
This study compares the frequency of signs and symptoms from the cervical spine in 24 patients diagnosed with Meniere's disease and 24 control subjects from a population sample. From a previous controlled comparative study concerning signs and symptoms of craniomandibular disorders, 24 patients diagnosed with Meniere's disease (10 males and 14 females) and their 24 matched control subjects participated in this investigation on the state of the cervical spine. Symptoms of cervical spine disorders, such as head and neck/shoulder pain, were all significantly more frequent in the patient group than in the control group. Most of the patients (75%) reported a strong association between head neck movements in the atlanto-occipital and atlanto-axial joints and triggered attacks of vertigo. Also, 29% of the patients could influence their tinnitus by mandibular movements. Signs of cervical spine disorders, such as limitations in side-bending and rotation movements, were significantly more frequent in the patient group than in the control group. Tenderness to palpation of the transverse processes of the atlas and the axis, the upper and middle trapezius, and the levator scapulae muscle were also significantly more frequent in the patient group. The study shows a much higher prevalence of signs and symptoms of cervical spine disorders in patients diagnosed with Meniere's disease compared with control subjects from the general population.  相似文献   
957.
MTX-induced hepatic injury and liver enzyme elevations have been demonstrated after treatment of leukemia, gestational disease and during treatment of psoriasis and rheumatoid arthritis. A 40-year-old man with a long standing history of rheumatoid arthritis was treated with MTX over a 6 month period and developed an overwhelming hepatic necrosis. He was successfully transplanted.  相似文献   
958.
959.
7-Ethyl-10-[4-(1-piperidino)-1-piperidino]-carbonyloxycamptothecin (CPT-11, 100286-90-6) is one of the most promising novel anticancer agents, especially for lung cancer. 7-Ethyl-10-hydroxycamptothecin (SN-38), an active metabolic of CPT-11, has much stronger cytotoxicity than CPT-11. The present study was designed to evaluate the distribution and behavior of CPT-11 and SN-38 in lung lymph circulation following intravenous infusion. Awake sheep with chronically instrumented lung lymph fistulas were prepared. The concentrations of CPT-11 and SN-38 in plasma and lung lymph fluid were measured after intravenous infusion of 100 mg/body of CPT-11 for 90 min. SN-38 constantly showed higher lymph to plasma concentration ratios than those of CPT-11, and the % area under the curve (AUC) ratio of SN-38/CPT-11 in lymph fluid was significantly higher than that in plasma. These data indicated that SN-38 distributed in lung tissue moved more easily into lung lymph fluid than CPT-11, and might be more rapidly metabolized in lung tissue than plasma. CPT-11 may have favorable therapeutic effects on intrathoracic malignancies such as lung cancer and lymph metastasis.  相似文献   
960.
Under the auspices of its Dioxin Characterization Program, members of The Vinyl Institute (VI), have analyzed for potential polychlorinated dibenzodioxin/furan (PCDD/F) concentrations in polyvinylchloride (PVC) resins, treated wastewater effluent and ethylene dichloride (EDC) product at EDC, vinyl chloride monomer (VCM) and PVC manufacturing facilities in the U.S. and Canada. No 2,3,7,8-tetrachlorodibenzodioxin (TCDD) was detected in any sample analyzed under the program to date. Trace concentrations (low pg/g) of PCDD/F were detected in only a few samples of PVC resins and EDC product. Treated wastewater contained low ppq concentrations of PCDD/F. All concentrations are expressed as Toxic Equivalents (TEQ). Extrapolation of these data shows that the contribution of EDC/VCM/PVC manufacturing via these media constitutes substantially less than 1 percent of the estimated annual U.S. dioxin releases to the environment.  相似文献   
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