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71.
72.
To elucidate the fundamental differences and similarities of the neuropathological features and etiopathogenesis of the amyotrophic lateral sclerosis (ALS) and parkinsonism-dementia complex (PDC) of Guam, we conducted a topographic, quantitative and histological investigation of tau-containing neurons, neurofibrillary tangles (NFTs), Bunina bodies and ubiquitinated inclusion bodies in 27 non-ALS non-PDC Guamanian subjects, as well as 10 Guam ALS patients, 28 PDC patients, and 5 patients with combined ALS and PDC (ALS-PDC). The topographic distribution of NFTs was basically the same in each disease and also in the non-ALS non-PDC group. There were relatively few, if any, NFTs in non-ALS non-PDC subjects and ALS patients, but there were many, especially in the frontal and temporal cortex, in Guam PDC and ALS-PDC patients. The histological and ultrastructural features of Bunina bodies in Guam ALS and ALS-PDC patients were similar to those reported in classic ALS. The ratio of occurrence of the inclusion in Guam ALS and ALS-PDC patients was similar to that reported so far in classic ALS. Ubiquitinated skein-like inclusion bodies were observed in the spinal anterior horn cells in Guam ALS and ALS-PDC patients. These findings indicate that classic ALS does exist on Guam, that NFTs in Guam ALS patients are merely a background feature widely dispersed in the population, that the mechanism of neuronal degeneration of Guam ALS is basically different from that of PDC, and that Guam ALS occurs initially as classic ALS.Supported in part by a Grant-in-Aid for Scientific Research (c) 05680653 from the Ministry of Education, Science and Culture and a research grant for CNS degenerative diseases from the Ministry of Health and Welfare, JapanMedical student of Leiden University, Holland, in 1981. He stayed on Guam and accomplished his thesis on part of this study under the guidance of Drs. K.-M. Chen and K. Oyanagi.  相似文献   
73.
A group of 43 patients from seven families affected by Creutzfeldt-Jakob disease (CJD) with the codon 178Asn mutation of the PRNP amyloid precursor gene is compared to a group of 211 patients with the sporadic form of the disease. As a group, the patients with the codon 178Asn mutation had an earlier age at onset of illness (almost always presenting as an insidious loss of memory), a longer duration of illness, and an absence of periodic electroencephalographic activity. Transmission of disease to primates was accomplished using brain tissue homogenates from 6 of 10 patients, resulting in significantly shorter incubation periods than those due to sporadic CJD inocula. These findings are interpreted and discussed in terms of possible differences in the temporospatial evolution of damage to the brain, and of accelerated induction of polymerized amyloid protein by its mutationally altered template precursor.  相似文献   
74.
Isonicotinic hydrazide, a drug that decreases the level of GABA, when injected subcutaneously in control and scrapie-infected hamsters induced tonic-clonic seizures in scrapie hamsters significantly earlier (P<0.0001) than in control animals. This suggests depression of the GABAergic system in scrapie-infected hamsters. To determine whether this lesion is pre or postsynaptic we measured the level of GABA, glutamate, cGMP and cAMP and the GABA-benzodiazepine receptor complex.  相似文献   
75.
Olivopontocerebellar atrophy in a large Iakut kinship in eastern Siberia   总被引:1,自引:0,他引:1  
One-hundred cases of olivopontocerebellar atrophy, type 1, were found and studied in the Iakut population of Eastern Siberia. The disease followed a slowly progressive course of cerebellar insufficiency caused by degeneration in the cerebellar cortex, nuclei pontis, and inferior oliva. The disorder shows an autosomal dominant pattern of inheritance with a lower penetrance in females. The disease spread from a small region in the Aldan valley 200 to 300 years ago.  相似文献   
76.
In the past, investigators have been able to produce hepatic amebiasis in laboratory animals only by direct introduction of parasites into the liver or its vasculature, or by other artificial manipulations. A natural model of human visceral amebiasis has been lacking. We document an extensive outbreak of amebic dystentery which took place in a colony of spider monkeys; severe hepatic abscesses occurred in many animals. The spider monkey is highly susceptible to infection with Entamoeba histolytica and could provide a valuable model for the study of the pathogenesis of invasive amebiasis.  相似文献   
77.
Kuru reached epidemic proportions by the mid-twentieth century among the Fore people of New Guinea and disappeared after the abolition of cannibalistic rituals. To determine susceptibility to kuru and its role in the spread and elimination of the epidemic, we analyzed the PRNP gene coding sequences in 5 kuru patients; no germline mutations were found. Analysis of the PRNP 129 methionine (M)/valine (V) polymorphism in 80 patients and 95 unaffected controls demonstrated that the kuru epidemic preferentially affected individuals with the M/M genotype. A higher representation of M/M carriers was observed among the affected young Fore males entering the age of risk, whereas a lower frequency of M/M homozygotes was found among the survivors. M/V and V/V genotypes predisposed to a lower risk of disease development and longer incubation times. These findings are relevant to the current outbreak of variant Creutzfeldt-Jakob disease (vCJD) in the United Kingdom, because all vCJD patients tested thus far have been M/M carriers.  相似文献   
78.
We report a simplified method for culturing fetal central nervous system cells predominantly inducing neurons that grow, differentiate, and live in vitro for as long as 10 weeks. These central nervous system cells form a confluent cell culture in which about 80% of the cells are fully differentiated neurons producing interconnecting axons and dendrite processes and live upon a sparse underlying population of fibrillary and protoplasmic astrocytes, oligodendrocytes, and fibroblasts. Morphological and cytochemical characteristics of these cell types, based on immunofluorescent cell specific markers and silver staining of neurons, are presented.  相似文献   
79.
80.
Pathogenesis of experimental Hantaan virus infection in laboratory rats   总被引:3,自引:0,他引:3  
Summary Weanling Fischer rats inoculated intramuscularly with Hantaan virus (strain 76–118) developed subclinical infections characterized by transient viremia and shedding of virus in saliva, persistence of virus in lung, pancreas, spleen and liver, and development of fluorescent and neutralizing antibodies in serum with immune complex deposition in lung. Viremia and virus shedding in saliva occurred 10 to 13 days after inoculation. Horizontal intracage transmission of infection occurred between 35 and 63 days post-inoculation, long after disappearance of virus in oropharyngeal secretions and blood. Multiple attempts to demonstrate infectious virus in feces and urine during this period were unsuccessful. The inability to detect virus in urine samples of experimentally infected rats may have resulted from intermittent or low-titered viruria. This contrasts sharply with the prolonged high-titered viruria reported in striped field mice(Apodemus agrarius) infected with Hantaan virus, suggesting differences in the mode(s) of virus transmission in nature.With 2 Figures  相似文献   
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