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101.
A better understanding of the role of genetic factors in affective disorders is likely to result from investigating more homogeneous populations. To achieve this goal, we have systematically studied patients who are excellent responders to long-term lithium treatment and their relatives. In the families of 71 such probands, we have analyzed the mode of inheritance by comparing the observed morbidity risks with the risks expected under different genetic models. The results demonstrate major-gene effects in the transmission of primary affective disorders; the polygenic model with sex-specific thresholds could be rejected. Discrimination between the autosomal and X-chromosome models was not possible, but the autosomal recessive model predicts more realistic, gender-specific frequencies of affective disorders in the general population. These results suggest that autosomal recessive inheritance deserves serious consideration in molecular genetic investigations.  相似文献   
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103.
5-Azacytidine is being used for reactivation of tumor suppressor genes. However, its administration during DNA repair pontentiates hepatocarcinogenesis. We observed chemopreventive activities by vitamin A and beta-carotene during early hepatocarcinogenesis. Thus, in the present study we evaluated vitamin A and beta-carotene chemopreventive potential during early hepatocarcinogenesis potentiated by 5-azacytidine. Wistar rats received vitamin A (VAA group), beta-carotene (betaCA group) or corn oil (CO and COA groups). After three weeks of treatment, all animals were initiated with 1,2-dimethylhydrazine. Twelve hours later VAA, betaCA and COA groups received a single dose of 5-Azc. Hepatocytes were selected/promoted by 2-acetylaminofluorene and 70% partial hepatectomy. All animals were sacrificed six weeks after initiation. Compared to CO group (without 5-azacytidine), COA group presented higher (p<0.05) nodule multiplicity, larger (p<0.05) gamma-GT positive lesions that occupied a larger (p<0.05) area of liver section. Compared to COA group, VAA group presented decreased (p<0.05) nodule multiplicity while betaCA group tended to present smaller gamma-GT positive lesions and to decrease occupied liver section. These results reinforce vitamin A and beta-carotene chemopreventive potential. Considering that 5-azacytidine potentiates hepatocarcinogenesis, more studies are needed to elucidate the efficacy and safety of this drug for cancer control.  相似文献   
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105.
Objective: To evaluate the prevalence of ADHD in a group of parents of children with ADHD compared with the general population. To compare academic level, unemployment aid rate and marital separations/divorce of this parents sample. Methodology: The experimental group was formed by the parents of 60 children with ADHD. The control group was formed by the parents of 60 healthy children. To assess the retrospective and current ADHD symptomatology among the parents of the sample the Wender Utah Rating Scale (WURS) and the Attention Deficit Hyperactivity Disorder-rating scale (ADHD.rs) were used. Also, the Hollingshead Four-Factor Index of Socioeconomic status (SES-Child) was used. Results: 20.33% of the mothers in the case group met criteria for a retrospective diagnosis of ADHD, while none of the control group mothers met criteria (p < .01). Regarding fathers, there was a retrospective ADHD diagnosis in 25% of the case group compared to 10% in the control group (p < .01). In terms of the current symptoms, 25.42% of the mothers and 21.43% of fathers in the case group met diagnostic criteria for probable ADHD compared to 1.67% in the control group (p < .01 in both genders). Parents in the case group had a lower academic level (p < .01), received more unemployment aid (p = .02) and reported a higher rate of marital separation or divorce (p = .02). Conclusions: Parents of children with ADHD have a higher incidence of retrospective and current ADHD diagnosis and they also present worse socioeconomic factors.  相似文献   
106.
M J Naya  D Pereboom  J Ortego  J O Alda    A Lanas 《Gut》1997,40(2):175-181
BACKGROUND: Reactive oxygen metabolites have been associated with gastrointestinal injury. OBJECTIVE: To investigate whether mucosal reactive oxygen metabolites are involved in acid and pepsin induced oesophagitis, and if so, which specific metabolites. METHODS: The effects of free radical scavengers and the anti-inflammatory drug ketotifen on rabbit oesophagitis induced by acidified pepsin were studied. Isolated oesophageal cells were obtained before and after oesophageal injury and the generation of superoxide anion and hydrogen peroxide was analysed by flow cytometry. The presence of inflammatory cells was determined by indirect immunofluorescence with a mouse antirabbit CD11b antibody. RESULTS: Of the free radical scavengers tested, superoxide dismutase, which reacts with the superoxide anion, significantly reduced oesophagitis, whereas catalase, which reacts with hydrogen peroxide, had only a mild effect and dimethylsulphoxide had no effect. Ketotifen significantly reduced the inflammation and also prevented the induction of oesophagitis. Isolated cells obtained from the oesophageal mucosa after acidified pepsin exposure generated increased amounts of superoxide anions, which were mainly produced by CD11b positive cells. CONCLUSIONS: Reactive oxygen metabolites, especially superoxide anion, produced by inflammatory cells play a significant part in the genesis of oesophagitis induced by acid and pepsin in rabbits and might be a target for future medical therapy.  相似文献   
107.

Background

Anti-viral prophylaxis is used to prevent the transmission of influenza. We studied serological confirmation of 2009 Influenza A (H1N1) infections during oseltamivir prophylaxis and after cessation of prophylaxis.

Methods

Between 22 Jun and 16 Jul 09, we performed a cohort study in 3 outbreaks in the Singapore military where post-exposure oseltamivir ring chemoprophylaxis (75 mg daily for 10 days) was administered. The entire cohort was screened by RT-PCR (with HA gene primers) using nasopharyngeal swabs three times a week. Three blood samples were taken for haemagglutination inhibition testing - at the start of outbreak, 2 weeks after completion of 10 day oseltamivir prophylaxis, and 3 weeks after the pandemic's peak in Singapore. Questionnaires were also administered to collect clinical symptoms.

Results

237 personnel were included for analysis. The overall infection rate of 2009 Influenza A (H1N1) during the three outbreaks was 11.4% (27/237). This included 11 index cases and 16 personnel (7.1%) who developed four-fold or higher rise in antibody titres during oseltamivir prophylaxis. Of these 16 personnel, 8 (3.5%) were symptomatic while the remaining 8 personnel (3.5%) were asymptomatic and tested negative on PCR. Post-cessation of prophylaxis, an additional 23 (12.1%) seroconverted. There was no significant difference in mean fold-rise in GMT between those who seroconverted during and post-prophylaxis (11.3 vs 11.7, p = 0.888). No allergic, neuropsychiatric or other severe side-effects were noted.

Conclusions

Post-exposure oseltamivir prophylaxis reduced the rate of infection during outbreaks, and did not substantially increase subsequent infection rates upon cessation. Asymptomatic infections occur during prophylaxis, which may confer protection against future infection. Post-exposure prophylaxis is effective as a measure in mitigating pandemic influenza outbreaks.  相似文献   
108.
Moreno C, Merchán‐Naranjo J, Álvarez M, Baeza I, Alda JA, Martínez‐Cantarero C, Parellada M, Sánchez B, de la Serna E, Giráldez M, Arango C. Metabolic effects of second‐generation antipsychotics in bipolar youth: comparison with other psychotic and nonpsychotic diagnoses.
Bipolar Disord 2010: 12: 172–184. © 2010 The Authors.
Journal compilation © 2010 John Wiley & Sons A/S. Objectives: Despite known metabolic effects of second‐generation antipsychotics (SGAs) on children and adolescents, comparative effects in youth with different diagnoses remain underreported. We compared differences in metabolic changes three months after starting treatment with SGAs in youth with bipolar disorder and with other psychotic and nonpsychotic disorders. Methods: Weight and metabolic differences among diagnostic groups before and three months after starting treatment with SGAs were compared in a naturalistic cohort of children and adolescents (14.9 ± 3.0 years) diagnosed with bipolar disorder (n = 31), other psychotic disorders (n = 29), and other nonpsychotic disorders (n = 30), with no (35.6%) or very little (6.6 ± 9.0 days) previous exposure to antipsychotics. Composite measurements of significant weight gain [weight increase ≥ 5% at three months or increase ≥ 0.5 in body mass index (BMI) z‐score] and ‘risk for adverse health outcome’ (≥ 95th BMI percentile, or ≥ 85th BMI percentile plus presence of one other obesity‐related complication) were included. SGAs (risperidone, olanzapine, and quetiapine) were prescribed in comparable proportion among groups. Results: Baseline weight and metabolic indices were not significantly different among diagnoses. Three months after starting treatment with SGAs, more than 70% patients had significant weight gain, BMI z‐score increased in all diagnostic groups (p < 0.001 for all comparisons), total cholesterol increased in the bipolar (p = 0.02) and psychotic (p = 0.01) disorder groups, low‐density lipoprotein cholesterol increased in the bipolar group (p = 0.02), and free T4 decreased in the psychotic disorder group (p = 0.05). More patients with bipolar disorder presented overweight plus ≥ 1 obesity‐related complication at follow‐up. Conclusions: There are early weight gain and metabolic changes across diagnoses in youth treated with SGAs.  相似文献   
109.
110.
Kisspeptin is a potent stimulator of GnRH secretion that has been implicated in the feedback actions of ovarian steroids. In ewes, the majority of hypothalamic kisspeptin neurons are found in the arcuate nucleus (ARC), with a smaller population located in the preoptic area. Most arcuate kisspeptin neurons express estrogen receptor-alpha, as do a set of arcuate neurons that contain both dynorphin and neurokinin B (NKB), suggesting that all three neuropeptides are colocalized in the same cells. In this study we tested this hypothesis using dual immunocytochemistry and also determined if kisspeptin neurons contain MSH or agouti-related peptide. To assess colocalization of kisspeptin and dynorphin, we used paraformaldehyde-fixed tissue from estrogen-treated ovariectomized ewes in the breeding season (n = 5). Almost all ARC, but no preoptic area, kisspeptin neurons contained dynorphin. Similarly, almost all ARC dynorphin neurons contained kisspeptin. In experiment 2 we examined colocalization of kisspeptin and NKB in picric-acid fixed tissue collected from ovary intact ewes (n = 9). Over three quarters of ARC kisspeptin neurons also expressed NKB, and a similar percentage of NKB neurons contained kisspeptin. In contrast, no kisspeptin neurons stained for MSH or agouti-related peptide. These data demonstrate that, in the ewe, a high percentage of ARC kisspeptin neurons also produce dynorphin and NKB, and we propose that a single subpopulation of ARC neurons contains all three neuropeptides. Because virtually all of these neurons express estrogen and progesterone re-ceptors, they are likely to relay the feedback effects of these steroids to GnRH neurons to regulate reproductive function.  相似文献   
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