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For more than two decades, the International Narcotic Control Board (INCB) has tried to stop harm reduction and its HIV prevention programs. This posture is based on a fundamental misunderstanding of their responsibilities and of drug addiction itself – i.e. as a public health and clinical care matter made criminal by decree. A recent focal point for the Board's action has been rejecting the use of supervised injection facilities to reduce morbidity and mortality of drug injectors. They single out individual countries and attempt to bully them into rejecting such programs under the banner of the United Nations (falsely) and in the name of international treaties. Their unrelenting and unjustified badgering of signatories to the international treaties that established the INCB is not only unjustified; it is an affront to one of the core purposes of the Board itself: to ensure adequate medical supplies and safe use of controlled substances. The INCB's ill-conceived obsession with intravenousaddiction as a crime flies in the face of the medical view and policies of the World Health Organization and the universally endorsed principles of the General Assembly of the United Nations.  相似文献   
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Although membrane sites from brain, labelled with [3H]glutamate (Glu) under sodium-free conditions, are thought to represent excitatory receptors, certain anomalous characteristics of the kinetics of apparent binding raised the question of whether transport might contribute to this process, prompting a closer examination of it. Hyperosmolar media and low incubation temperatures (4 degrees C) both led to decreases in the apparent specific binding of [3H]glutamate to membranes from the brain of the rat in the presence of chloride. Furthermore, only 15% of the [3H]glutamate, bound at 37 degrees C, was dissociable when the membranes were then cooled to 4 degrees C. The binding of [3H]glutamate was increased in the presence of certain dipeptides such as L-phenylalanyl-L-glutamate (Phe-Glu); and the binding augmented by the presence of Phe-Glu, was also sensitive to temperature and osmolarity of the incubation buffer. Sonication of membranes in 5 mM glutamate increased the apparent binding of [3H]glutamate and abolished the stimulatory effect of Phe-Glu. These findings are consistent with the hypothesis that chloride-dependent association of [3H]glutamate with membranes from brain reflects, in part, a sequestration process, which may be driven by glutamate exchange.  相似文献   
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Oral rehydration therapy (ORT) was hailed 10 years ago as potentially the most significant medical advance of the century. ORT is a simple and inexpensive means of treating diarrheal dehydration, which killed approximately 5 million children each year in the late 1970s. Today 25% of the world's children have access to ORT, and it is estimated that every year it saves 500,000 lives. Where ORT is not widely available, diarrheal dehydration remains the leading killer of children. It is still responsible for 25% of the 250,000 worldwide child deaths each week. Because there have been problems with acceptance of the ORT formula of salt, sugar, and water, researchers have been experimenting with cereal-based oral rehydration formulas that are much like traditional home remedies for diarrhea. In addition to relieving dehydration, these cereal-based formulas lessen severity and duration of diarrheal illness. Critics, however, claim that they fail to provide a child with sufficient calories, and call for a combination of ORT with early feeding--4-8 hours after completion of rehydration. Even with growing evidence of the benefits of early feeding, the practice of withholding food from children with diarrhea persists in the developing world and in the U.S. Problems in developing countries are greater, but each year 14 of every 1,000 American infants are hospitalized because of acute diarrhea. The major hurdle that ORT faces in the U.S. is that it is a simple form of therapy attempting to displace a higher technology. As long the U.S. health care system serves as a model for developing countries, distrust of ORT by American doctors will hamper efforts to spread ORT in the developing world.  相似文献   
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The development of a vaccine against hepatitis B prepared with purified and inactivated HBs Ag is described. This vaccine has been applied in patients and staff members of haemodialysis centres. Safety and efficiency of the vaccine are very satisfactory. The response of patients to immunisation was significantly lower compared to the response of the staff members. None of the volunteers who had a primary response to immunisation developed signs of clinical or biological hepatitis.  相似文献   
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OBJECTIVE: The objective of this study was to examine the effect of breast density and age on screening mammograms with false-positive findings. MATERIALS AND METHODS: The study sample was taken from the Washington State Mammography Tumor Registry, which links data from participating radiologists with the Puget Sound Cancer Surveillance System and the Washington State Cancer Registry. Participants (n = 73,247) were women 35 years old and older who underwent screening mammography for which an assessment and a four-category density rating were coded. A total of 46,340 mammograms were sampled to avoid interpreter bias. In this study of false-positive mammograms, only women with no diagnosis of breast cancer within 12 months of the index mammogram were included. Logistic regression was used to estimate the odds ratios of a false-positive mammogram being associated with each category of breast density or age, adjusting for the other factor as a covariate. RESULTS: After controlling for breast density, we found that the risk of a false-positive mammogram was not affected by age (p = 27). However, the trend of increasing risk of a false-positive mammogram with increasing breast density was highly significant (p < .001). Women with extremely dense breast tissue were almost two times more likely to have a false-positive mammogram than were women with fatty breast tissue. This effect persisted after controlling for age. CONCLUSION: Breast density, not age, is an important factor when predicting risk of a false-positive mammogram. Breast density should be considered when educating individual women on the risks and benefits of screening mammography.  相似文献   
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PURPOSE: To assess the efficacy and toxicity of bortezomib (Velcade; Milennium Pharmaceuticals Inc, Cambridge, MA; formerly PS-341) in patients with metastatic renal cell carcinoma (RCC). PATIENTS AND METHODS: Thirty-seven patients with metastatic RCC were treated with bortezomib. The first 25 patients enrolled onto the trial were treated with a dose of 1.5 mg/m2. The dose was decreased to 1.3 mg/m2 for the subsequent 12 patients, because more than 50% of the patients treated at the higher dose required dose reductions. Bortezomib was given by intravenous administration on a twice-weekly schedule for 2 weeks followed by 1 week without treatment until progression or unacceptable toxicity occurred. Twenty-three patients (62%) previously had undergone nephrectomy, and 19 patients (51%) had previously been treated with cytokine therapy. RESULTS: Of the 37 assessable patients, the best response was a partial response in four patients (11%; 95% CI, 3% to 25%) and stable disease in 14 patients (38%; 95% CI, 23% to 55%). The four patients with partial response experienced response durations of 8, 8+, 15+, and 20+ months. Grade 2 or 3 sensory neuropathy was present in 10 patients (53%) overall. One patient in the 1.5 mg/m2 group had grade 3 sensory neuropathy; no grade 3 sensory neuropathy was seen in the 1.3 mg/m2 group. CONCLUSION: The results of this trial suggest that bortezomib has an antitumor effect in individual patients with metastatic RCC. The small proportion of patients who achieved a partial response does not support routine use in metastatic RCC. Efforts to identify the molecular profile associated with clinical response or combination therapy with interferon alfa or other novel agents, may be considered.  相似文献   
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