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991.
Lee K  Solts B  Burns J 《AIDS care》2002,14(6):851-857
Developments in anti-HIV medication have meant that people with HIV/AIDS are now living longer, with some authors arguing that HIV should now be defined as a manageable rather than terminal illness. However uncertainty about the long-term efficacy of such treatments remains. This research aimed to examine the psychosocial impact of the new treatments and to explore whether, and in what ways, they affect psychological wellbeing. Clients were also asked about their use of services and whether they thought services should be changing in response to new pharmacological treatments. A semi-structured interview schedule was developed to elicit the views of six service users. From multiple readings of the qualitative data generated, prominent themes were identified suggesting that participants had ambivalent feelings about taking antiretroviral combination therapy and that being well with HIV raised a number of difficult issues. Four main themes were revealed: (1) disruptions in daily living: antiretrovirals as intrusions to life, (2) the tablets as a visible marker for HIV infection, (3) tempered optimism and increasing horizons, (4) an uncertain and fragile future: life without benefits and services. The results were discussed in terms of limitations of the current study and suggestions for further research.  相似文献   
992.
A deficiency of adenosine deaminase, an enzyme important in purine nucleoside catabolism, is associated with a severe combined immunodeficiency disease in children. Inhibition of this enzyme in vitro and in vivo results in an impairment in lymphoblast proliferation. We have investigated the pharmacologic inhibition of this enzyme by 2'-deoxycoformycin in 15 patients with hematologic malignancies. Biochemical consequences of the administration of this agent were closely monitored in erythrocytes, nucleated peripheral blood and bone marrow cells, serum, and urine. A marked rise in erythrocyte dATP was accompanied by a depletion of ATP in those patients exhibiting toxicity. Most patients excreted large amounts of deoxyadenosine but not adenosine in the urine. Serum deoxyadenosine rose in patients demonstrating a marked decrease in cell mass. The biochemical disturbances and clinical toxicity, including hepatic, renal, and conjunctival abnormalities, were usually reversible. Central nervous system toxicity, which potentially was the most serious consequence, was associated with high erythrocyte dATP/ATP ratios and high levels of cerebrospinal fluid deoxyadenosine. In patients with lymphoma and leukemia, objective responses were observed but were short- lived. Patients with chronic lymphocytic leukemia receiving weekly low doses of the drug demonstrated minimal toxicity and some efficacy. The chemotherapeutic potential o 2'-deoxycoformycin, as either a single agent or in combination with Ara-A, merits further exploration.  相似文献   
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Due to their small size and complex structure, diagnosing injury of the proximal wrist ligamentous structures can be challenging. The triangular fibrocartilage complex (TFCC) is an example of one such structure, for which lesions may be missed unless high-resolution magnetic resonance imaging (MRI) obtained via a standard matrix with a small field of view or high-resolution imaging matrix (small spatial scale matrix elements/large matrix size) is utilized. While there have been recent advances in increasing MRI spatial resolution, attempts at improved visualization by isolated increase in the spatial resolution will be ineffective if the signal-to-noise ratio (SNR) of the images obtained is low. Additionally, high contrast resolution is important to facilitate a more precise visualization of these structures and their pathology. Thus, a balance of the three important imaging factor qualifications of high spatial resolution, high SNR, and high contrast resolution must be struck for optimized TFCC and wrist imaging. The goal of this article, then, is to elucidate the theory and techniques of effective high-resolution imaging of the proximal ligamentous structures of the wrist, balancing SNR and high contrast resolution constraints, and focusing on imaging of the TFCC as a prototypical example.  相似文献   
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Intracranial hypotension is a disorder of CSF hypovolemia due to iatrogenic or spontaneous spinal CSF leakage. Rarely, positional headaches may progress to coma, with frequent misdiagnosis. The authors review reported cases of verified intracranial hypotension-associated coma, including 3 previously unpublished cases, totaling 29. Most patients presented with headache prior to neurological deterioration, with positional symptoms elicited in almost half. Eight patients had recently undergone a spinal procedure such as lumbar drainage. Diagnostic workup almost always began with a head CT scan. Subdural collections were present in 86%; however, intracranial hypotension was frequently unrecognized as the underlying cause. Twelve patients underwent one or more procedures to evacuate the collections, sometimes with transiently improved mental status. However, no patient experienced lasting neurological improvement after subdural fluid evacuation alone, and some deteriorated further. Intracranial hypotension was diagnosed in most patients via MRI studies, which were often obtained due to failure to improve after subdural hematoma (SDH) evacuation. Once the diagnosis of intracranial hypotension was made, placement of epidural blood patches was curative in 85% of patients. Twenty-seven patients (93%) experienced favorable outcomes after diagnosis and treatment; 1 patient died, and 1 patient had a morbid outcome secondary to duret hemorrhages. The literature review revealed that numerous additional patients with clinical histories consistent with intracranial hypotension but no radiological confirmation developed SDH following a spinal procedure. Several such patients experienced poor outcomes, and there were multiple deaths. To facilitate recognition of this treatable but potentially life-threatening condition, the authors propose criteria that should prompt intracranial hypotension workup in the comatose patient and present a stepwise management algorithm to guide the appropriate diagnosis and treatment of these patients.  相似文献   
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Purpose

The optimal timing for starting renal replacement therapy (RRT) in patients with acute kidney injury (AKI) is unknown. Defining current practice is necessary to design interventional trials. We describe the current Canadian practice regarding the timing of RRT initiation for AKI.

Methods

An observational study of patients undergoing RRT for AKI was undertaken at 11 intensive care units (ICUs) across Canada. Data were captured on demographics, clinical and laboratory findings, indications for RRT, and timing of RRT initiation.

Results

Among 119 consecutive patients, the most common ICU admission diagnosis was sepsis/septic shock, occurring in 54%. At the time of RRT initiation, the median and interquartile range (IQR) serum creatinine level was 322 (221-432) ??mol·L?1. The mean (SD) values for other parameters were as follows: Sequential Organ Failure Assessment (SOFA) score 13.4 (4.1), pH 7.25 (0.15), potassium 4.6 (1.0) mmol·L?1. Also, 64% fulfilled the serum creatinine-based criterion for Acute Kidney Injury Network (AKIN) stage 3. Severity of illness, measured using Acute Physiology and Chronic Health Evaluation (APACHE II) and SOFA scores, did not correlate with AKI severity as defined by the serum creatinine-based AKIN criteria. Median (IQR) time from hospital and ICU admission to the start of RRT was 2.0 (1.0-7.0) days and 1.0 (0-2.0) day, respectively.

Conclusion

Patients admitted to an ICU who were started on RRT generally had advanced AKI, high-grade illness severity, and multiorgan dysfunction. Also, they were started on RRT shortly after hospital presentation. We describe the current state of practice in Canada regarding the initiation of RRT for AKI in critically ill patients, which can inform the designs of future interventional trials.  相似文献   
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SUMMARY:: Orthopaedic trauma fellows have completed several years of specialized training for this moment, their first job. Due partially to the success and popularity of the Orthopaedic Trauma Association, finding the right position has become more difficult. There are a variety of ways to go about finding the desired position to start a career, but the best advice involves a combination of strategies.  相似文献   
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