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41.
CONTEXT: Several reports from small clinical trials have suggested that estrogen replacement therapy may be useful for the treatment of Alzheimer disease (AD) in women. OBJECTIVE: To determine whether estrogen replacement therapy affects global, cognitive, or functional decline in women with mild to moderate AD. DESIGN: The Alzheimer's Disease Cooperative Study, a randomized, double-blind, placebo-controlled clinical trial conducted between October 1995 and January 1999. SETTING: Thirty-two study sites in the United States. PARTICIPANTS: A total of 120 women with mild to moderate AD and a Mini-Mental State Examination score between 12 and 28 who had had a hysterectomy. INTERVENTIONS: Participants were randomized to estrogen, 0.625 mg/d (n = 42), or 1.25 mg/d (n = 39), or to identically appearing placebo (n = 39). One subject withdrew after randomization but before receiving medication; 97 subjects completed the trial. MAIN OUTCOME MEASURES: The primary outcome measure was change on the Clinical Global Impression of Change (CGIC) 7-point scale, analyzed by intent to treat; secondary outcome measures included other global measures as well as measures of mood, specific cognitive domains (memory, attention, and language), motor function, and activities of daily living; compared by the combined estrogen groups vs the placebo group at 2, 6, 12, and 15 months of follow-up. RESULTS: The CGIC score for estrogen vs placebo was 5.1 vs 5.0 (P = .43); 80% of participants taking estrogen vs 74% of participants taking placebo worsened (P = .48). Secondary outcome measures also showed no significant differences, with the exception of the Clinical Dementia Rating Scale, which suggested worsening among patients taking estrogen (mean posttreatment change in score for estrogen, 0.5 vs 0.2 for placebo; P = .01). CONCLUSIONS: Estrogen replacement therapy for 1 year did not slow disease progression nor did it improve global, cognitive, or functional outcomes in women with mild to moderate AD. The study does not support the role of estrogen for the treatment of this disease. The potential role of estrogen in the prevention of AD, however, requires further research.  相似文献   
42.
Diagnostic accuracy of dementia with Lewy bodies   总被引:4,自引:0,他引:4  
BACKGROUND: Diagnostic criteria for dementia with Lewy bodies (DLB) are still evolving. No data exist on prospective differentiation of DLB and Alzheimer disease (AD). OBJECTIVE: To examine the clinician's diagnostic accuracy for DLB and analyze factors contributing to false-positive DLB diagnoses. METHODS: A prospective series of 10 patients with clinically diagnosed DLB who came to autopsy was compared with 32 autopsy-confirmed cases of DLB (27 Lewy body variant, 5 diffuse Lewy body disease) and 20 autopsy-confirmed cases of AD (matched on age, sex, education, and initial Mini-Mental State Examination score) with regard to distinguishing and/or confounding clinical features. RESULTS: The clinical diagnostic accuracy for DLB was 50%, with 5 of the 10 patients clinically presumed to have DLB confirmed at autopsy. Of the 5 misdiagnosed cases, 4 had AD and 1 had progressive supranuclear palsy. The misdiagnosed DLB cases who had pure AD had fewer hallucinations (25%) than those with Lewy body variant (63%) or diffuse Lewy body disease (100%) (P = .048); however, an equal amount of spontaneous (in the absence of neuroleptics) extrapyramidal signs was found. There were no differences among groups with regard to daily fluctuations in cognition or falls. Compared with the AD control group, the misdiagnosed DLB cases with pure AD showed significantly more spontaneous extrapyramidal signs (P< or =.02). CONCLUSIONS: The clinician's diagnostic accuracy for DLB was poor. Early spontaneous extrapyramidal signs in AD were associated with false-positive clinical diagnoses of DLB. The distinction between DLB and AD may be improved by greater emphasis on hallucinations.  相似文献   
43.
44.
OBJECTIVE: To determine the timing of cholinergic loss and reduction of synapses in AD. BACKGROUND: Decrements in neocortical synapses and cholinergic function occur in AD and correlate with cognitive decline. However, how early in the disease process these changes appear remains unclear. METHODS: An autopsy series of 89 demented patients with pathologically confirmed AD (National Institute on Aging and Consortium to Establish a Registry for Alzheimer's Disease criteria) and 18 normal control subjects (NC). The AD cases were stratified according to their last Mini-Mental State Examination (MMSE) score prior to death as mild (MMSE = 20; n = 14), moderate (MMSE = 10 to 19; n = 20), severe (MMSE = 1 to 9; n = 29), and very severe (MMSE = 0; n = 26). Midfrontal (MF) synapse density was assessed by dot-immunobinding assay for synaptophysin (Syn), and MF choline acetyltransferase (ChAT) activity was determined using standard protocols. RESULTS: Compared with those in NC, neither Syn nor ChAT was appreciably reduced in patients with mild AD at death. Decline of ChAT was significant only in AD patients who died in the late stages of the disease and was maximal in those who had more severely deteriorated. In contrast, decline of Syn was significant and almost maximal in patients in intermediate or moderate stages. Consequently, the last MMSE score prior to death correlated more strongly with ChAT than Syn when the AD cohort included more impaired patients (r = 0.46 versus 0.40). The reverse occurred when only less impaired patients (MMSE = 10) were included in the analyses (r = 0.28 versus 0.64). There was only a modest correlation between Syn and ChAT activity. CONCLUSIONS: The results imply an asynchronous pattern of decline of synapses and cholinergic activity, with Syn loss preceding ChAT decrements. However, neither MF synapse reduction nor cholinergic dysfunction appears to be an early event in AD.  相似文献   
45.
Psychotic symptoms are common in Alzheimer's disease (AD) and clinicoanatomical and neuropsychological evidence indicate an association between these symptoms and frontal lobe dysfunction. Neuro-behaviors associated with frontal dysfunction were assessed in Alzheimer's disease (AD) patients with (n = 20) and without psychotic symptoms (n = 21) matched for mean age, education, gender, and dementia severity. The Frontal Lobe Personality Scale (FLOPs) was completed by patient caregivers to measure behaviors typically associated with frontal dysfunction. Findings indicated that AD patients with psychotic symptoms exhibited significantly greater neurobehavioral dysfunction (FLOPs M = 130.69, SD = 24.70) than AD patients without psychotic symptoms (FLOPs M = 111.10, SD = 25.83). Subscale analyses indicated that psychotic AD patients were more dis-inhibited (M = 28.28, SD = 7.54) than patients without psychotic symptoms (M = 20.92, SD = 4.9). Findings are consistent with and contribute to previous neuropsychological and clinicoanatomical research suggesting increased frontal dysfunction in AD with psychotic symptoms and lend additional empirical support to subtyping AD based on the presence of psychotic symptoms. Furthermore, findings provide preliminary evidence indicating which specific type of neurobehavioral abnormalities are related to the presence of distressing psychotic symptoms.  相似文献   
46.
Reviews of stored electrograms from ICDs revealed a 5-30% incidence of short-long-short intervals preceding the onset of recurrent ventricular tachyarrhythmias. Rate stabilization by dedicated antibradycardia pacing algorithms has, therefore, been suggested to prevent onset of pause dependent tachyarrhythmias. However, the clinical efficacy of this approach has not been studied systematically. In a prospective multicenter crossover study, patients were randomized to activation or deactivation of an implemented ventricular rate stabilization algorithm (VRS) after first implant of a dual chamber ICD. After 3 months, all patients were crossed over to the alternate programming. The rate of appropriate spontaneous VA episodes was compared between VRS On and VRS Off. Stored electrograms were reviewed for evaluation of the mode of onset of tachyarrhythmias. Overall efficacy analysis was based on 309 patients enrolled in the study. Forty percent (124/309) of the patients experienced 4,973 VA episodes. Based on an intention-to-treat analysis, VRS Off and On arrhythmia incidence was 10.2 and 6.6 normalized to 3 months, respectively (risk reduction 35%; P = 0.18) On an on-treatment basis, a reduction from 9.0 episodes to 8.1 episodes (10% risk reduction, P = 0.24) was seen. In an extended Cox model adjusting for confounding variables, the relative risk for recurrent episodes was 0.92 during VRS On compared to Off (95% CI: 0.58-1.48; P = 0.74). During VRS Off, pause dependent onset was documented in only 36 (8%) of 427 visually analyzed episodes. There was no significant reduction in the incidence of recurrent ventricular tachyarrhythmias with VRS On compared to the Off programming in this prospective study.  相似文献   
47.
3H-Apomorphine interactions with dopamine receptors in calf brain   总被引:2,自引:0,他引:2  
3H-apomorphine binds to membranes from areas of the corpus striatum and limbic system of calf brain saturable and with a drug specificity indicating that it labels dopamine receptors. In terms of drug specificity, log-logit displacement curve slopes and number of binding sites, 3H-apomorphine interacts with receptors in a manner more like 3H-dopamine than 3H-haloperidol. These properties of 3H-apomorphine binding are those of an apparently "pure" agonist in contrast to the partial agonist effects of apomorphine upon the dopamine-sensitive adenylate cyclase.  相似文献   
48.
Growth factors have been identified as the primary cause of osteoinduction in bone healing. Transforming growth factor beta (TGF- beta) has been shown to promote bone formation and is present in bone in high quantities. The aims of the present study were to isolate TGF- beta from human bone, demonstrate its biologic activity, and analyze the effects of conventional sterilization techniques on activity. Bone, obtained from femoral heads of five patients (mean age, 70 years) was ground, demineralized, and freeze-dried, and samples from each patient were divided into three groups: no treatment, sterilization with 1.60 to 1.94 Mrad of 60Co irradiation, and sterilization with ethylene oxide (ETO). Carrier-free recombinant TGF-beta control was also treated and was totally inactivated by ETO but not by irradiation (p < 0.01). TGF- beta activity in demineralized bone was not significantly diminished (p > 0.1) by either sterilization procedure, and substantial amounts of active TGF-beta were recovered in all bone samples: 1.04 +/− 0.77 ng per mg of protein in irradiated samples, 0.67 +/− 0.26 ng per mg in ETO- treated samples, and 1.04 +/− 0.33 in untreated samples, respectively (mean +/− SD). Although a recent report demonstrated that the osteoinductive activity of bone morphogenetic protein in bone powder is diminished considerably by ETO and by 2.5 Mrad of irradiation sterilization of bone powder, these data demonstrate that TGF-beta activity, with its osteoinductive properties, was not destroyed in more coarsely ground, demineralized bone by ETO or by lower doses of irradiation. These findings support the use of human bone allografts in clinical instances involving impaired bone formation.  相似文献   
49.
We have found that the addition of 10 mM inorganic phosphate to DHA in CPD-adenine maintains ATP levels at normal or higher than normal values for six weeks of storage. 2,3-DPG values are slightly lowered by the extra phosphate, but are still maintained at approximately half normal for four weeks by the DHA. The addition of a higher phosphate concentration, 20 mM, to DHA produced lower levels of ATP and 2,3-DPG than those observed with 10 mM phosphate, although both levels were better than in the CPD-adenine control. pH values in this experiment were lowest in the three preservatives containing DHA, probably indicating increased lactate production due to metabolism of this triose sugar, in addition to dextrose present in CPD.  相似文献   
50.
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