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1.
OBJECTIVES: Parkinson's disease (PD) frequently affects both the extrapyramidal system and the autonomic nervous system (ANS), the latter also being sometimes disturbed by PD medications. Specifically selegiline is known to disturb cardiovascular ANS functions and may cause or enhance orthostatic hypotension. METHODS: In order to study the effect of the withdrawal of selegiline on the regulation of blood pressure (BP) in advanced PD, an orthostatic test was performed in 14 PD patients with wearing-off before the morning levodopa dose and thereafter repetitively at 1-h intervals for up to 4 h. A Unified Parkinson's Disease Rating Scale motor score evaluation was also carried out hourly. The tests were repeated after a 4-week selegiline washout period. RESULTS: Selegiline withdrawal decreased systolic BP significantly during the on-stage in a supine position as well as during the orthostatic test. The initial drop of BP in the orthostatic test was significantly smaller after selegiline withdrawal. The heart rate remained unaffected.  相似文献   
2.
INTRODUCTION: It is generally assumed that executive dysfunctions in Parkinson's disease (PD) are caused by degeneration of the basal ganglia or frontal cortex or both. However, there have been few studies investigating the relationship between executive dysfunctions and cerebral pathological change. The objective of this study was to evaluate various cognitive functions in non-demented patients with PD, and to compare the fractional anisotropy (FA) values of PD patients with and without executive dysfunction. MATERIALS AND METHODS: Twenty-one consecutive non-demented patients with PD were enrolled in this study. Patients were divided into two groups on the basis of their Wisconsin Card Sorting Test score. RESULTS: There was significant FA reduction in the left parietal white matter in the group in which the number of categories achieved was 2. CONCLUSION: Accumulating evidence suggests that conventional 'frontal' tasks correlate with both frontal lobe and parietal lobe function, and we suggest that pathological changes in the left parietal lobe may cause, in part, disturbances in executive tasks in PD.  相似文献   
3.
OBJECTIVE: Dementia occurs frequently in patients with Parkinson's disease (PD). However, the nature of the dementing process remains controversial. We evaluated various cognitive functions in patients with PD, compared fractional anisotropy (FA) values between PD patients with and without dementia. METHODS: Thirty-seven consecutive patients with Hoehn-Yahr stage III or IV PD participated in this study. Patients were divided into two groups: (i) PD with dementia group (PDD) and (ii) PD without dementia group (PDND). There were 11 PDD and 26 PDND cases. Ten controls were also studied. RESULTS: The PDD group showed significant FA reduction in the bilateral posterior cingulate bundles compared with PDND. FA values in the left posterior cingulate bundle showed significant correlations with many cognitive parameters. INTERPRETATION: Our results showed that the posterior cingulate areas play some important roles in the dementing process in PDD. However, as the pathological processes responsible for dementia in PD patients may be multifaceted, further studies are necessary.  相似文献   
4.
OBJECTIVE: In this study, the validity of a motor task, i.e., the Global Mobility Task (GMT), was assessed in a group of Parkinson's disease (PD) patients. PATIENTS AND METHODS: Fifty-eight PD patients (mean age: 68.7 years) and 18 healthy subjects (mean age: 65.8 years) were enrolled in the study. The GMT measures the ability of an adult to roll over on the floor and stand up in five steps using two parameters: 'Time' and 'Score', i.e., the time needed and the ability to perform each step of the task. As the GMT has never been evaluated before, internal consistency and concurrent and discriminative validity were considered in assessing its characteristics in a group of PD patients at the beginning and at the end of a motor rehabilitation program. To determine whether the GMT could also quantify the extrapyramidal impairment, we compared data collected using this task with data obtained using clinical scales such as the Unified Parkinson's Disease Rating Scale III (UPDRS part III) and Hoehn & Yahr's score. RESULTS: Results showed that the GMT had good consistency and inter-rater reproducibility, was closely related to clinical scales and was able to detect the amelioration of extrapyramidal symptoms at the end of the motor rehabilitation program. CONCLUSION: we propose the GMT as a tool for measuring impaired mobility in PD patients and for evaluating the objective effects of motor rehabilitation programs.  相似文献   
5.
Interleukin-15 promotes T-cell proliferation, induction of cytolytic effector cells including natural killer (NK) and cytotoxic cells and stimulates B-cell to proliferate and secrete immunoglobulins. RANTES is a C-C beta chemokine with strong chemoattractant activity for T lymphocytes and monocytes. OBJECTIVES: The objective of our study was to find out whether IL-15 and RANTES are involved in the possible inflammatory reactions of PD. PATIENTS AND METHODS: We measured by immunoassay serum IL-15 and RANTES levels in 41 patients with PD in comparison with serum levels in 19 healthy subjects age and sex-matched. IL-15 and RANTES levels were correlated with sex, age, disease duration. H-Y stage and the UPDRS III score in all the studied groups and were also correlated with treatment status in PD patients. RESULTS: The PD group presented with significantly increased RANTES levels as compared to the control group (P = 0.0009). No difference was observed as regards IL-15 levels. A strong and significant correlation between RANTES levels and UPDRS III score was observed in PD patients (R(s) = 0.42, P = 0.007). Untreated patients had significantly higher RANTES levels as compared to the controls. CONCLUSIONS: Our findings may suggest a recruitment of activated monocytes, macrophages and T lymphocytes to sites of inflammation in the central nervous system of PD patients.  相似文献   
6.
Objective –  The objective of the present study was to find risk factors for low bone mineral density (BMD) in patients with Parkinson's disease (PD).
Material and methods –  Twenty-six PD patients and 26 age-and sex-matched healthy controls were assessed twice within a 1-year period. PD symptoms, body weight, body fat mass, BMD, physical activity, smoking and serum concentrations of several laboratory analyses were investigated.
Results –  BMD in different locations was lower in PD patients compared with their controls and decreased during the investigated year. BMD was lower in PD patients with low body weight. BMD Z -score of trochanter in the PD group was directly correlated to the degree of physical activity and indirectly to the length of recumbent rest. Total body BMD Z -score in the PD group was directly correlated to the degree of rigidity. Serum 25-hydroxy-vitamin D was slightly lower in PD patients.
Conclusion –  Low body weight and low physical activity were risk factors for low BMD in PD, while rigidity seemed to be protective.  相似文献   
7.
Objectives –  The aim of the study was to visualize cortical function in Parkinson's patients with various degrees of cognitive impairment.
Materials and methods –  Thirty-seven patients with Parkinson's disease and three with Parkinson plus syndromes underwent cognitive assessment and rCBF using 99mTC-HMPAO-SPECT.
Results –  Almost no regional reductions in cerebral blood flow were seen in patients without cognitive impairment ( n  = 16). Limited, mainly posterior, blood flow reductions were seen in patients with mild cognitive impairment ( n  = 14), whereas the reductions were extensive and bilaterally symmetric, involving both anterior and posterior brain regions in patients with dementia ( n  = 10).
Conclusions –  The findings suggest a widespread cortical, mainly posterior type of dysfunction and a relationship between the degree of cognitive impairment and the magnitude of the dysfunction.  相似文献   
8.
9.
Expansion of the polyQ repeat in ataxin-2 results in degeneration of Purkinje neurons and other neuronal groups including the substantia nigra in patients with spinocerebellar ataxia type 2 (SCA2). In animal and cell models, overexpression of mutant ataxin-2 induces cell dysfunction and death, but little is known about steady-state levels of normal and mutant ataxin-2 and cellular mechanisms regulating their abundance. Based on preliminary findings that ataxin-2 interacted with parkin, an E3 ubiquitin ligase mutated in an autosomal recessive form of Parkinsonism, we sought to determine whether parkin played a role in regulating the steady-state levels of ataxin-2. Parkin interacted with the N-terminal half of normal and mutant ataxin-2, and ubiquitinated the full-length form of both wild-type and mutant ataxin-2. Parkin also regulated the steady-state levels of endogenous ataxin-2 in PC12 cells with regulatable parkin expression. Parkin reduced abnormalities in Golgi morphology induced by mutant ataxin-2 and decreased ataxin-2 induced cytotoxicity. In brains of SCA2 patients, parkin labeled cytoplasmic ataxin-2 aggregates in Purkinje neurons. These studies suggest a role for parkin in regulating the intracellular levels of both wild-type and mutant ataxin-2, and in rescuing cells from ataxin-2-induced cytotoxicity. The role of parkin variants in modifying the SCA2 phenotype and its use as a therapeutic target should be further investigated.  相似文献   
10.
The impairment of the mesostriatal dopaminergic system has been considered responsible for motor and affective disturbances associated with aging and a risk factor for Parkinson's disease. However, the basic mechanisms underlying this phenomenon are still unknown. Here we used biochemical, molecular and morphological techniques directed at detecting flaws in the dopamine synthesis route and signs of dopaminergic degeneration in the rat mesostriatal system during normal aging. We found two different age-related processes. One is characterized by a dopa decarboxylase decrease, and involves both the nigrostriatal and mesolimbic compartments, and is responsible for a moderate dopamine loss in the dorsal striatum, where other parameters of dopamine synthesis are not affected. The other is characterized by axonal degeneration with aggregation of phosphorylated forms of tyrosine hydroxylase (TH) and amyloid precursor protein in degenerate terminals, and alpha-synuclein in their original somata. This process is restricted to mesolimbic regions and is responsible for the decline of TH activity and l-dopa levels and the greater decrease in dopamine levels in this compartment. These findings suggest that both the nigrostriatal and the mesolimbic systems are vulnerable to aging, but in contrast to what occurs in Parkinson's disease, the mesolimbic system is more vulnerable to aging than the nigrostriatal one.  相似文献   
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