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101.
ABSTRACT

Thirty-eight men undergoing electroejaculation (EEJ) procedures for anejaculatory infertility were examined for the presence or absence of infection in urine and semen. In 29 spinal cord injury patients, a high incidence of infected urine and infected semen (41% and 56%, respectively) was seen, in contrast to patients with normal bladder function (0% and 11 %).

Urinary infection was associated with slightly lower sperm quality and lower pregnancy rates (10% vs 30% in the presence of sterile urine). Semen infection had no effect on sperm counts or pregnancy rates. If intermittent self-catheterization (ISC) was used to empty the neurogenic bladder, slightly better sperm quality was seen, the total failure rate was less, and much better pregnancy rates (44%) resulted than for patients using an alternative bladder management (7%).

Antibiotics did not reduce the incidence of urine or semen infection, but did improve sperm counts slightly. Continuous prophylaxis was associated with bacterial resistance to many oral antibiotics and had no advantage over a short course of antibiotics prior to the procedure.

Despite the above associations, the sperm quality in our patient population was never normal compared with that of men who ejaculate normally. We conclude that the low sperm quality seen in electroejaculation specimens from spinal cord injured males is not due entirely to infection or to the type of bladder management. Short courses of antibiotics, instead of continuous antibiotic prophylaxis, may be beneficial. Intermittent catheterization is superior to other methods of neurogenic bladder management in maintaining the fertility of spinal cord injured men.  相似文献   
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103.
The “aberrant salience” model proposes that psychotic symptoms first emerge when chaotic brain dopamine transmission leads to the attribution of significance to stimuli that would normally be considered irrelevant. This is thought to occur during the prodromal phase of psychotic disorders, but this prediction has not been tested previously. In the present study, we tested this model in 18 healthy volunteers and 18 unmedicated individuals at ultra-high risk of psychosis. Subjects performed the Salience Attribution Test, which provides behavioral measures of adaptive and aberrant motivational salience, during functional magnetic resonance imaging to assess neural responses to relevant and irrelevant stimulus features. On a separate occasion, the same subjects were also studied with [18F]fluorodopa positron emission tomography to measure dopamine synthesis capacity. Individuals at ultra-high risk of psychosis were more likely to attribute motivational salience to irrelevant stimulus features (t(26.7) = 2.8, P = .008), and this bias was related to the severity of their delusion-like symptoms (r = .62, P = .008). Ventral striatal responses to irrelevant stimulus features were also correlated with delusion-like symptoms in the ultra-high risk group (r = .59, P = .017). Striatal dopamine synthesis capacity correlated negatively with hippocampal responses to irrelevant stimulus features in ultra-high risk individuals, but this relationship was positive in controls. These data are consistent with the hypothesis that aberrant salience processing underlies psychotic symptoms and involves functional alterations in the striatum, hippocampus, and the subcortical dopamine system.Key words: psychosis, aberrant salience, salience attribution test, functional magnetic resonance imaging, positron emission tomography, dopamine  相似文献   
104.
Background: The psychosis phenotype appears to exist in the population as a continuum, but it is not clear if subclinical psychotic symptoms and psychotic disorders share the same neurobiology. We investigated whether the dopaminergic dysfunction seen in psychotic disorders is also present in healthy, well-functioning people with hallucinations. Methods: We compared dopamine synthesis capacity (using 6-[18F]fluoro-L-DOPA [[18F]-DOPA] positron emission tomography imaging) in 16 healthy individuals with frequent persistent auditory verbal hallucinations (hallucinating group) with that in 16 matched controls. Results: There was no significant difference in dopamine synthesis capacity in the striatum, or its functional subdivisions, between groups and no relationship between subclinical psychotic symptom severity or schizotypal traits and dopamine synthesis capacity in the hallucinating group. Conclusions: Altered dopamine synthesis capacity is unlikely to underlie subclinical hallucinations, suggesting that although there may be a phenomenological psychosis continuum, there are distinctions at the neurobiological level.  相似文献   
105.
Iatrogenic deaths are a concern for patients, physicians, and public health specialists. Most medicolegal investigation jurisdictions in the United States have the legal authority and mandate to investigate deaths associated with diagnostic/therapeutic procedures. Given the decreasing trends of autopsies performed in U.S. hospitals, forensic pathologists are likely to take on an even greater role in investigating these deaths. This is an overview and forensic pathological approach to fatal complications due to diagnostic and therapeutic medical events.  相似文献   
106.

Purpose

To review the evidence on safety of anterior lumbar interbody fusion (ALIF) and extreme lateral transpsoas interbody fusion (ELIF) in the treatment of degenerative spinal disorders with an emphasis on the association between neuromonitoring and complications.

Methods

We performed a systematic literature search in the Cochrane (CENTRAL), MEDLINE, EMBASE and the FDA Medical Devices databases. We abstracted information on study design, sample size, population, procedure, number and location of involved levels, follow-up time and complications, as well as information on conflict of interest and source of funding. In addition, for ELIF we collected information on the use of neuromonitoring during the procedure.

Results

34 publications were included in the review: 24 ELIF (all case series), 9 ALIF (8 randomized controlled trials and 1 case series) and one retrospective cohort that directly compared ELIF with ALIF. 18 out of 24 ELIF studies reported using neuromonitoring. The overall complication rate for ELIF was lower compared to ALIF without FDA reports (16.61 vs. 26.47 %, respectively). However, the rate of neurologic complications in ELIF was almost twice as high compared to ALIF without FDA reports (8.92 and 4.96 %, respectively). The rate of overall complications in ELIF studies that were reported using neuromonitoring was lower compared to the studies that did not report using neuromonitoring (16.34 vs. 21.74 %, respectively).

Conclusion

Although the overall complications rate for ELIF was lower compared to ALIF, ELIF is associated with a greater risk of neurological complications compared to ALIF even when used with neuromonitoring.
  相似文献   
107.
108.
OBJECTIVE: To provide a uniform platform from which to study acute liver failure, the U.S. Acute Liver Failure Study Group has sought to standardize the management of patients with acute liver failure within participating centers. METHODS: In areas where consensus could not be reached because of divergent practices and a paucity of studies in acute liver failure patients, additional information was gleaned from the intensive care literature and literature on the management of intracranial hypertension in non-acute liver failure patients. Experts in diverse fields were included in the development of a standard study-wide management protocol. MEASUREMENTS AND MAIN RESULTS: Intracranial pressure monitoring is recommended in patients with advanced hepatic encephalopathy who are awaiting orthotopic liver transplantation. At an intracranial pressure of > or =25 mm Hg, osmotic therapy should be instituted with intravenous mannitol boluses. Patients with acute liver failure should be maintained in a mildly hyperosmotic state to minimize cerebral edema. Accordingly, serum sodium should be maintained at least within high normal limits, but hypertonic saline administered to 145-155 mmol/L may be considered in patients with intracranial hypertension refractory to mannitol. Data are insufficient to recommend further therapy in patients who fail osmotherapy, although the induction of moderate hypothermia appears to be promising as a bridge to orthotopic liver transplantation. Empirical broad-spectrum antibiotics should be administered to any patient with acute liver failure who develops signs of the systemic inflammatory response syndrome, or unexplained progression to higher grades of encephalopathy. Other recommendations encompassing specific hematologic, renal, pulmonary, and endocrine complications of acute liver failure patients are provided, including their management during and after orthotopic liver transplantation. CONCLUSIONS: The present consensus details the intensive care management of patients with acute liver failure. Such guidelines may be useful not only for the management of individual patients with acute liver failure, but also to improve the uniformity of practices across academic centers for the purpose of collaborative studies.  相似文献   
109.
BACKGROUND: Research to address clinical symptoms and the way they change over time in an individual is of paramount importance to healthcare researchers who are interested in improving the quality of life for ill patients. However, typical statistical methods that rely on means can obscure individual trajectories of change. Visual graphical analysis (VGA) is a technique that can provide researchers with an alternative method of quantitative statistical analysis that is more sensitive to individual change and variation. OBJECTIVES: To (a) describe the use of VGA as a method to evaluate longitudinal data, (b) discuss challenges to using this method, and (c) offer recommendations for future research in which the method could be implemented. APPROACH: This methodological article uses data collected from a primary study to present the method of VGA. Daily self-reported sore mouth severity scores from patients receiving outpatient chemotherapy were used in this VGA. The steps of VGA include (a) determining inclusion criteria, (b) managing missing data, (c) creating visual graphs, (d) identifying specific patterns, and (e) performing validation and verification. DISCUSSION: Because symptoms occur differently for each patient, this method allows researchers to see symptom trajectories on an individual basis. Creation and analysis of longitudinal graphs could be used also to inspect other symptoms or clinical problems such as headaches, fatigue, constipation, nausea and vomiting, and psychological difficulties. The value of VGA is that it allows a researcher to study the patterns of an individual's experience, as opposed to averaging all individuals' responses over time. Although graphical analysis is exploratory in nature, it may lead to enhanced longitudinal recognition of symptoms that might not be identified otherwise by quantitative data analysis using summary statistics.  相似文献   
110.
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