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In experiment I a group of ameboid cells was isolated from a culture of cardiac muscle sixty-three days old, and cultivated in plasma. After several passages, they formed a dense tissue from which ameboid cells radiated. The culture was divided into two parts. The part cultivated in plasma alone kept its morphological characters and continued to produce ameboid cells. The part cultivated upon silk in plasma became modified; the cells lost their ameboid characters, and were transformed into large elongated cells which were united in chains, or interlaced to form a network. In experiment II the round cells taken from a culture of connective tissue seventy-four days old multiplied rapidly. They transformed themselves into elongated cells and produced, after a few passages, a mass of dense connective tissue. From the tissue a large number of elongated cells were constantly growing. In both experiments the tissues originated from the ameboid or round cells extirpated from cultures that were sixty-three and seventy-four days old respectively. These cultures were still growing actively thirty and forty days later; that is, more than one hundred days after the extirpation of the original fragments from the organism. These experiments show that from old cultures it is possible to isolate and propagate cells that belong to a definite type. A tissue, formed by a pure strain of cells, can be obtained in this way, and this new method may be of value in cytological investigations.  相似文献   
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We conducted a historical cohort study of 981 first-degree relatives of 162 patients with Parkinson's disease (PD) and of 838 first-degree relatives of 147 controls representative of the population of Olmsted County, Minnesota. In addition, we studied 2,684 first-degree relatives of 411 patients with PD referred to the Mayo Clinic. Relatives were interviewed and screened for tremor either directly or through a proxy, and those who screened positive were examined or copies of their medical records were obtained to confirm the diagnosis of essential tremor (ET). We also obtained ET information from a medical records-linkage system (family study method). In the population-based sample, the risk of ET was significantly increased for relatives of patients with onset of PD相似文献   
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Treatment of pediatric epilepsy: European expert opinion, 2007.   总被引:2,自引:0,他引:2  
BACKGROUND: Childhood epilepsies are a heterogeneous group of conditions that differ in diagnostic criteria and management and have dramatically different outcomes. Despite increasing data on treatment of epilepsy, research findings on childhood epilepsy are more limited and many clinical questions remain unanswered, so that clinicians must often rely on clinical judgment. In such clinical situations, expert opinion can be especially helpful. METHODS: A survey on pediatric epilepsy and seizures (33 questions and approximately 650 treatment options) was sent to 57 European physicians specializing in pediatric epilepsy, 42 (74%) of whom completed it. In some questions, the experts were asked to recommend overall treatment approaches for specific syndromes (the order in which they would use certain strategies). Most of the questions asked the experts to rate options using a modified version of the RAND 9-point scale for medical appropriateness. Consensus was defined as a non-random distribution of scores by chi-square test, with ratings used to assign a categorical rank (first line/usually appropriate, second line/equivocal, and third line/usually not appropriate) to each option. RESULTS: Valproate was treatment of choice for symptomatic myoclonic and generalized tonic-clonic seizures. For initial monotherapy for complex partial seizures, carbamazepine and oxcarbazepine were treatments of choice, with valproate also first line. As initial therapy for infantile spasms caused by tuberous sclerosis, viagabatrin was treatment of choice. As initial therapy for infantile spasms that are symptomatic in etiology, vigabatrin was also treatment of choice, with adrenocorticotropic hormone (ACTH) and prednisone other first-line options. As initial therapy for Lennox-Gastaut syndrome, valproate was treatment of choice. For acute treatment of a prolonged febrile seizure or cluster of seizures, rectal diazepam was treatment of choice. Valproate was treatment of choice as preventive therapy for febrile seizures. For benign childhood epilepsy with centro-temporal spikes, valproate was treatment of choice. For childhood and juvenile absence epilepsy, valproate was treatment of choice, with lamotrigine another first-line option (ethosuximide was another first-line option for childhood absence epilepsy). For juvenile myoclonic epilepsy in adolescent males, valproate was treatment of choice, with lamotrigine another first-line option; for juvenile myoclonic epilepsy in adolescent females, lamotrigine was treatment of choice, with valproate another firstline option. As initial therapy for neonatal status epilepticus, intravenous (IV) phenobarbital was treatment of choice. As initial therapy for all types of pediatric status epilepticus, IV diazepam was treatment of choice. For generalized tonic-clonic status epilepticus, rectal diazepam and IV lorazepam were also treatments of choice; for complex partial status epilepticus, IV lorazepam was another first-line option. CONCLUSION: The expert panel reached consensus on many treatment options. Within the limits of expert opinion and with the understanding that new research data may take precedence, the experts' recommendations provide helpful guidance in situations where the medical literature is scant or lacking. The information in this report should be evaluated in conjunction with evidence-based findings.  相似文献   
999.
1. Human thyroid tissue may be kept alive and in good condition in the Lindbergh apparatus for at least 3 weeks, in usable condition from 1 to 2 months, provided that the vascular tree remain patent and functioning. 2. Experiments with altered amounts of iodin, adrenalin, hormones, and other substances show constant results only in connection with eschatin and pitressin which, in concentrations of 1:1000 in the perfusate almost invariably cause hyperplasia of the explanted tissue. 3. The original state of the tissue and the character of the symptom complex in the patient from which it was taken appeared to play no part in the subsequent behavior of the tissue explants. 4. In one experiment a most remarkable metaplasia was observed in the explanted thyroid tissue during the 6 to 8 weeks that it remained in two apparatuses. The cause of this is not evident.  相似文献   
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