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71.
A series of recent studies demonstrated that the triazine herbicide atrazine, although not itself acutely toxic, potentiated the toxicity of certain organophosphate insecticides (OPs) to the midge Chironomus tentans. In the current study, a series of triazine herbicides and triazine herbicide degradation products were tested to determine if other triazines potentiate OP toxicity to midges. Chlorpyrifos and diazinon were the OPs tested. Toxicity tests were conducted using a factorial design and analysis of variance to statistically determine if each triazine had an effect on expected toxicity. Log-probit procedures were also used to evaluate the magnitude of change in median effective concentration (EC50) values during coexposure with each triazine. All of the triazine herbicides tested (atrazine, simazine, cyanazine, and hexazinone) were capable of potentiating the toxicity of the OPs, whereas the degradation products (s-triazine, deethylatrazine, and deisopropylatrazine) had less effect. In most cases, a triazine concentration of 100 μg/L was necessary to significantly increase OP toxicity, and higher concentrations of triazine caused a greater degree of potentiation. Changes in EC50 values ranged from no change to a 2.5-fold increase in toxicity. Generally, EC50 values changed by less than a factor of 2, indicating that the effect may be of limited concern in regard to future risk assessments of OPs.  相似文献   
72.
OBJECTIVE: To estimate the effectiveness of an inpatient, hospital-based cervical cancer screening program at a single institution. METHODS: Between January 1999 and December 2002, 1,117 women admitted to the Johns Hopkins Hospital underwent Papanicolaou (Pap) test screening during their hospital stay. In that time period, 111,933 women were screened at all of the combined Hopkins outpatient clinics. We compared rates of abnormal Pap tests in these cohorts (retrospective cohort study). Our main outcome measure was the prevalence of abnormal Pap tests among the screening population by age group, ethnicity, and insurance status compared between our outpatient and inpatient populations. RESULTS: The prevalence of abnormal Pap tests in the inpatient cohort was twice as high as that in the outpatient setting (15.5% versus 7%). The prevalence of high-grade squamous intraepithelial lesions (HSIL), the immediate precursor lesion to cervical cancer, was nearly 5-fold higher in the inpatient cohort compared with the outpatient cohort (3% versus 0.7%). In multivariable models, younger women had greater risk for all types of abnormal Pap tests, and black women had greater risk for HSIL. Previous abnormal Pap and human immunodeficiency virus-positive status were associated with all abnormal tests and with HSIL results. CONCLUSIONS: A hospital-based, inpatient Pap test program is an efficient strategy for targeting limited screening funds toward women at high risk of invasive cervical cancer. LEVEL OF EVIDENCE: II-2  相似文献   
73.
STAT1: a modulator of chemotherapy-induced apoptosis   总被引:6,自引:0,他引:6  
  相似文献   
74.
The authors retrospectively explored cortical differences between 26 patients with temporal lobe epilepsy and psychosis of epilepsy (POE), 24 patients with temporal lobe epilepsy (TLE) alone, and 20 healthy comparison subjects. Using voxel-based morphometry based on statistical parametric mapping (SPM99), which is an unbiased and fully automated technique to test for morphometric differences, magnetic resonance imaging (MRI) 3D-datasets were acquired and analyzed. There were no significant cortical gray matter differences between the POE and the TLE group. Since cortical pathology is prominent in schizophrenia, POE may be a clinical entity separate from schizophrenia.  相似文献   
75.
We investigated the effect of galvanic skin response (GSR) biofeedback training on seizure frequency in patients with treatment-resistant epilepsy. Eighteen patients with drug-refractory epilepsy were randomly assigned either to an active GSR biofeedback group (n = 10) or to a sham control biofeedback group (n = 8). Biofeedback training significantly reduced seizure frequency in the active biofeedback group (P = 0.017), but not the control group (P > 0.10). This was manifest as a significant between-group difference in seizure reduction (P 0.01). Furthermore, there was a correlation between degree of improvement in biofeedback performance and reduction of seizure frequency (rho = 0.736, P = 0.001), confirming that the effect of biofeedback treatment was related to physiological change. Our findings highlight the potential therapeutic value of GSR biofeedback in reducing seizure frequency in patients with drug-resistant epilepsy.  相似文献   
76.
The psychiatric comorbidity of epilepsy   总被引:8,自引:0,他引:8  
Several studies have assessed the prevalence of psychiatric disorders in epilepsy. They are characterized by considerable heterogeneity, because of differences in the population setting and type of study. A non-systematic review of the literature allows us to draw some useful, although not definite, conclusions. Six per cent of people with epilepsy in the general population appear to suffer from a psychiatric disorder, while this rises to 10-20% in populations with temporal lobe and/or refractory epilepsy. Mood disorders are the most common culprit (24-74%), particularly depression (30%), followed by anxiety disorders (10-25%), psychoses (2-7%) and personality disorders (1-2%). This comorbidity appears to be related to endogenous and exogenous (including iatrogenic) factors and to the severity and chronicity of epilepsy. Conditions such as schizophrenia-like psychosis of epilepsy and interictal dysphoric disorder are represented only in epilepsy. Adequate recognition and treatment of psychiatric conditions in epilepsy is essential for patient management because of their considerable burden in morbidity and quality of life.  相似文献   
77.
Objective: To investigate dopamine transporter binding in Gilles de la Tourette syndrome (GTS) with SPECT and [123I]FP‐CIT. Method: Ten neuroleptic naïve/free patients with GTS, and 10 age‐ and gender‐matched normal volunteers were studied. Subjects were clinically evaluated. GTS severity and affective symptoms were measured and the presence of GTS‐related behaviours were recorded. Results: The GTS group showed significantly higher binding in both caudate and putamen nuclei than the controls. No associations were found between striatal binding ratios and measures of affect or GTS‐related behaviours. Conclusion: Patients with GTS show higher striatal binding of FP‐CIT to the striatum in comparison with age‐ and gender‐matched control subjects, indicating that dopamine transporter abnormalities are involved in the pathophysiology of GTS. These abnormalities appear to be distributed across both caudate and putamen.  相似文献   
78.
OBJECTIVES: The objectives of this study were to ascertain long-term survival and patterns of care among women diagnosed with ovarian tumors of low malignant potential (LMP) in a population-based data set. METHODS: Using the NCI's Surveillance, Epidemiology, and End Results (SEER) database, we identified 2818 women diagnosed with ovarian tumors of low malignant potential between 1988 and 1997. RESULTS: By FIGO stage, 10-year relative survival was as follows: stage I, 99%; stage II, 98%; stage III, 96%; and stage IV 77%. One-quarter of women with stage I disease underwent partial or unilateral oophorectomy only, while women with more advanced disease commonly underwent omentectomy, unilateral or bilateral oophorectomy, and hysterectomy. Adjuvant chemotherapy was given to about 30% of women with stage III and IV disease. Radiation therapy was rarely used. We observed no significant changes in primary surgery or adjuvant treatment over time. CONCLUSIONS: The diagnosis of an ovarian tumor of LMP conveys a relatively benign prognosis. Conservative surgery should be considered in younger women with early-stage disease. There are insufficient data to support a role for adjuvant chemotherapy for women with advanced disease.  相似文献   
79.
80.
Trimble CL  Trimble EL 《Oncology (Williston Park, N.Y.)》2003,17(11):1563-7; discussion 1567-70, 1575
Clinical and laboratory reports suggest that ovarian tumors of low malignant potential (LMP) represent a "grab bag" of tumors, with different etiologies, molecular biologies, and prognoses. As a result, data on incidence and prognosis may be quite unreliable. Diagnosis is best made on permanent section. Half of women under age 40 undergo conservative, fertility-sparing surgery when diagnosed with an ovarian tumor of LMP, but no adjuvant therapy has been shown to prolong survival in this population. In addition to the various controversies surrounding LMP tumors, this review will address prognostic markers, risk of malignant transformation, treatment of progressive disease, surveillance after conservative surgery, and future directions for research.  相似文献   
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