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2.
We report on the effect of age and chronic caloric restriction (CR) on insulin binding and glucose transporter content in both diaphragm and heart muscle membrane of young (11 months), mid-age (17 months), and old (29 month) ad libitum fed and CR Brown-Norway rats. The control animals received rat chow ad lib and CR animals were allowed 60% of ad libitum food. The CR regimen was initiated at four months of age and the animals were maintained on their respective diets until necropsy. There was no effect of age on insulin binding for either ad libitum or CR animals at each age evaluated. Caloric restriction significantly lowered insulin levels at each age studied when compared to the ad libitum-fed rats. However, CR animals were noted to have increased insulin binding (p < 0.001) compared to ad libitum-fed animals at each age for diaphragm muscle. For the heart, there appeared to be a decreased binding, particularly at higher insulin concentrations, in CR-fed animals. There was no net change in Glut-1 or Glut-4 levels for heart muscle membrane, or Glut-4 levels for diaphragm muscle membrane between ad libitum or CR animals. This data indicates that caloric restriction may have tissue-specific effects for insulin receptor binding, and that the improved insulin sensitivity in CR states is not a result of altered glucose transporter protein content.  相似文献   
3.
A 30-year-old man presented with a subacute course of myelopathic signs and symptoms. Magnetic resonance imaging demonstrated an epidural mass lesion of the spinal canal at the cervicothoracic junction causing compression of the spinal cord. Laminectomy with resection of this lesion revealed a large varix with acute and chronic thrombus. Postoperatively, an improvement in neurological function occurred. Spinal epidural varicosities have been reported as an etiological factor in lumbar and sacral radiculopathies. This is the first reported case of spinal cord compression in association with spinal epidural varices. The diagnosis, pathophysiology, and management of this disorder are presented.  相似文献   
4.
Report of the results of 4 surgically treated epiphyseal injuries with progressing deformities in the lower extremities (3 injuries type V, 1 epiphyseal fracture type IV according to Salter and Harris). Our Surgical procedure consisted in a resection of the posttraumatic transphyseal bony bridge with a following interposition of a silastic block to prevent again transphyseal blocking. The indications for such a surgical procedure is explained possibilities leading to failures are discussed. The results of our experimental studies being the basis for such operations are reported.  相似文献   
5.
Outcome analysis in 654 surgically treated lumbar disc herniations.   总被引:10,自引:0,他引:10  
This article reports the outcomes of 654 consecutive patients treated during a 4.5-year period. Patients had a microdiscectomy, a laminectomy plus microdiscectomy, or a decompressive laminectomy with a microdiscectomy. The causes of ruptured discs were lifting (31.4%), falls (10.2%), and sports (10.0%). Almost all patients had complained of leg pain (99%), and 79% had radicular pain in a dermatomal distribution. Thirty-three percent of the patients had been involved in industrial accidents, and 6% had legal claims pending during the surgical period. Almost 11% of the patients had complications, and there was one death caused by abdominal arterial bleeding. Patients were also rated according to the Prolo Functional-Economic Outcome Rating Scale to improve the ability to compare series in the future. Almost 80% of the patients had good outcomes as defined by scores on this scale of 8 (16.2%), 9 (33.2%), and 10 (26.9%). Several conclusions can be drawn from the results of this series: 1) most patients had good outcomes; 2) patients with nonindustrial injuries had better outcomes than did patients with industrial injuries; 3) professionals with legal concerns and laborers with industrial insurance had good outcomes; and 4) the Functional-Economic Outcome Rating Scale appears to be a useful tool for comparing different procedures more objectively and for comparing the outcomes across series.  相似文献   
6.
The position of motoneurons which reinnervate the superior oblique muscle (SOM), normally exclusively innervated by contralateral trochlear motoneurons, was studied in Xenopus using retrograde tracing techniques. The trochlear nerve was cut at its decussation in 49 larvae of different ages and, after subsequent regeneration, the total number of trochlear motoneurons was found to be reduced to about 50% of the controls. In contrast, the number of ipsilateral trochlear motoneurons was increased. Cutting the trochlear nerve at later stages may result in absence of this nerve. In some animals the SOM was innervated either by superior rectus or, more frequently, by inferior oblique motoneurons alone; the latter is known to act predominantly as an antagonist of the SOM.  相似文献   
7.
The intention of this investigation was to ascertain the effect of maternal exposure to cigarette smoke on the early postnatal morphogenesis of pulmonary interstitum in offspring. Female rats were chronically exposed to whole cigraette smoke. Offspring of these and control animals were sacrificed at postnatal day 15, and their tissues were prepared for quantitative and qualitative analyses. Results indicate a diminished quantitative representaion of parenchymal tissue (P <0.01) and a slower pace of secondary septal growth (P <0.07) in the experimental lung. Furthermore, a greater cellular volume density (P <0.0002) was ascertained for the experimental septal inerstitium. There was proportionately less of elastin substances (P < 0.009), collagen together with basal laminae (P < 0.0008), and nonfibrillar, amorphous matrix (P < 0.02) in the experimental extracellular stroma. Fribrillar collagen and nonfibrillar matrix were represented quantitatively 6.3 times more in the experimental extracellular interstitum than elastin, whereas that ratio for the control tissue was only 4.2. Most experimental interstitial cells (80%) contained numerous lipid globules, which, in contrast, were only occasionally present in control cells (7.3%). Experimental cells, consequently, possessed a larger cross-sectional diameter and a smaller nucleus-to-cytoplasm volume ratio than control cells. These divergent developmental patterns are possibly suggestive of a delayed differentiation of interstitial cells and a modified production to degradation balance of stromal proteins in offspring of animals chronically exposed to whole cigarette smoke.  相似文献   
8.
Needle puncture and other accidents that occur during surgery and other procedures may lead to viral infections of medical personnel, notably by hepatitis C (HCV) and human immunodeficiency virus (HIV), now that hepatitis B can be prevented by vaccination. A new surgical glove called G-VIR, which contains a disinfecting agent for enveloped viruses, has been developed. Herpes simplex type 1 (HSV) was used as a standard enveloped virus in both in vitro and in vivo tests of the virucidal capacity of the glove. Bovine viral diarrhea virus (BVDV) and feline immunodeficiency virus (FIV) were used as models for HCV and HIV, respectively. For in vitro study, a contaminated needle was passed through a glove and residual virus was titrated; for in vivo studies, animals were stuck with a contaminated needle through a glove. Despite variation in virus enumeration inherent in the puncture technique, statistical evaluation showed that infection was reproducibly and substantially reduced by passage through the virucidal layer. For BVDV, the amount of virus passing through the virucidal glove was reduced in 82% of pairwise comparisons with control gloves that lacked the virucidal agent; when plaque counts were adjusted to a common dilution, the median count for the virucidal glove was on the average reduced >10-fold. In experiments in which the proportion of wells infected with FIV was measured, the ratio of TCID(50) values (control glove to G-VIR) was >15, and probably much higher. For HSV, the amount of virus passing through the virucidal glove was reduced in 81% of comparisons with control gloves; the median of adjusted plaque counts was reduced on the average approximately eightfold or ninefold. In vivo tests with FIV and HSV in cats and mice, respectively, found smaller percentage reductions in infection than the in vitro tests but confirmed the virucidal effect of the gloves.  相似文献   
9.
A detection system forLegionella DNA in urine samples based on the polymerase chain reaction (PCR) was developed and tested on infected guinea pigs and patients suffering from pneumonia. Results were compared with standard methods for diagnosis of Legionnaires' disease. A primer system was selected which amplifies a 108 bp DNA fragment of the 5S rRNA gene. The sensitivity of the PCR system was one femtogram of extractedLegionella DNA. Three methods were tested for pretreatment of urine samples. Of these, the Geneclean II kit (Bio 101, USA) gave the best results for artificially contaminated urine samples as well as those from infected guinea pigs or patients. Thirty-seven urine samples from 15 guinea pigs intraperitoneally infected with eitherLegionella pneumophila serogroup 1, 3 and 6 orLegionella micdadei, 26 urine samples of 21 patients suffering from pneumonia, and 30 control samples of patients with urinary tract infection (UTI) were tested.Legionella DNA was detected in 29 of the guinea pig urine samples; whereas, urinary antigen detection using EIA was positive in only 20 of the samples. PCR was also positive in the samples of 11 patients with pneumonia, 9 of which were confirmed by other microbiological methods, such as culture, direct fluorescent antibody test, urinary antigen detection and antibody testing. However, of the 30 control samples from patients with UTI, three samples yielded positive results. The results demonstrate thatLegionella DNA is excreted in the urine of infected individuals and that the PCR shows a higher degree of sensitivity than EIA to the detection of solubleLegionella antigen in urine. Although the positive results obtained from control samples are a potential limitation of the test, these preliminary data suggest that PCR can be a sensitive method for the diagnosis of legionellosis from urine samples.  相似文献   
10.
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