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21.
A group of destructive changes occurring in jaws in patients with maxillary complete dentures and mandibular removable partial dentures (bilaterally) has been described in the literature as the combination syndrome. However, this condition is not clinically observed in all patients. The aim of this study was to establish the prevalence index on signs of combination syndrome and to verify whether these changes also occurred in patients rehabilitated with a mandibular removable partial denture (unilaterally). Sample was composed of 44 patients, completely edentulous in the maxilla. Thirty-two patients had a Kennedy Class I removable partial denture and 12 a Kennedy Class II. Three major alterations were observed in 20.5% of the studied population. Nevertheless, these changes were present only in 25% of patients with Kennedy Class I removable partial denture. Based on the findings of this study, it can be concluded that patients with Kennedy Class II removable partial denture do not have similar signs that lead to the combination syndrome’s condition.  相似文献   
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Pituitary tumors are the most common primary intracranial neoplasms. Although most pituitary tumors are considered typically benign, others can cause severe and progressive disease. The principal aims of pituitary tumor treatment are the elimination or reduction of the tumor mass, normalization of hormone secretion and preservation of remaining pituitary function. In spite of major advances in the therapy of pituitary tumors, for some of the most difficult tumors, current therapies that include medical, surgical and radiotherapeutic methods are often unsatisfactory and there is a need to develop new treatment strategies. Gene therapy, which uses nucleic acids as drugs, has emerged as an attractive therapeutic option for the treatment of pituitary tumors that do not respond to classical treatment strategies if the patients become intolerant to the therapy. The development of animal models for pituitary tumors and hormone hypersecretion has proven to be critical for the implementation of novel treatment strategies and gene therapy approaches. Preclinical trials using several gene therapy approaches for the treatment of anterior pituitary diseases have been successfully implemented. Several issues need to be addressed before clinical implementation becomes a reality, including the development of more effective and safer viral vectors, uncovering novel therapeutic targets and development of targeted expression of therapeutic transgenes. With the development of efficient gene delivery vectors allowing long-term transgene expression with minimal toxicity, gene therapy will become one of the most promising approaches for treating pituitary adenomas.  相似文献   
24.

Background  

The Internet has been increasingly utilized in biomedical research. From online searching for literature to data sharing, the Internet has emerged as a primary means of research for many physicians and scientists. As a result, Web-based surveys have been employed as an alternative to traditional, paper-based surveys. We describe DADOS-Survey, an open-source Web-survey application developed at our institution that, to the best of our knowledge, is the first to be compliant with the Checklist for Reporting Results of Internet E-Surveys (CHERRIES). DADOS-Survey was designed with usability as a priority, allowing investigators to design and execute their own studies with minimal technical difficulties in doing so.  相似文献   
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The PEL1/PGS1 gene of the yeast Saccharomyces cerevisiae is essential for the viability of rho /rho° mutants and the normal cardiolipin content of cells. The PEL1-GFP fusion gene has been found to complement the pel1/pgs1 mutation and its fluorescent protein was localized to mitochondria similarly to the β-galactosidase activity of a protein encoded by the PEL1-lacZ fusion gene. The expression of the PEL1-lacZ reporter gene was repressed in cells grown in the presence of inositol and choline, reduced in the ino2 and ino4 strains, but constitutive in the opi1 null-mutant strain. The results demonstrate that Pel1p, playing a vital role in cells impaired in the mitochondrial DNA, is localized in the mitochondria and expressed in response to inositol and choline. Received: 15 June / 15 July 1998  相似文献   
27.

Background  

Although regulatory compliance in academic research is enforced by law to ensure high quality and safety to participants, its implementation is frequently hindered by cost and logistical barriers. In order to decrease these barriers, we have developed a Web-based application, Duke Surgery Research Central (DSRC), to monitor and streamline the regulatory research process.  相似文献   
28.
OBJECTIVE: To assess the beliefs of climacteric women regarding their health, menopause, and hormone replacement therapy (HRT). DESIGN: Medical students asked to interview 526 healthy women, ranging from 40 to 64 years of age, between January and February of 2002. Of that number, 26 (4.9%) declined to participate in the interview. Thus, 500 women were interviewed about their beliefs and perceptions regarding their quality of life and health risks, as well as their opinions on menopause and HRT. RESULTS: The mean age of the sample was 53.3 +/- 6.2 years; 83.4% were postmenopausal, and 18.8% were HRT users. Of the women interviewed, 38.6% believed that their health was good. Although 78.8% thought that cancer is the main cause of death, 64% of them considered themselves to be at high risk for cardiovascular disease and osteoporosis. Most (64%) believed that menopause deteriorates the quality of life and that it increases cardiovascular risk (52.4%) and osteoporosis (72.0%). The HRT users perceived that they had better health status (48.9% v 36.2%, P < 0.02) and smaller cardiovascular risk (54.3% v 66.3%, P < 0.04) than did the nonusers; however, they ignored the preventive effect of estrogens in osteoporosis. CONCLUSIONS: Women believe that menopause deteriorates their health. The HRT users perceived themselves to be healthier and to have a smaller risk for cardiovascular disease.  相似文献   
29.
The intercalated islands are intra-amigdaloid clusters of D1 receptor rich GABAergic neurons, which control impulse traffic between the basolateral complex and the central nucleus of the amygdala. As dopaminergic transmission within the amygdala may play a role in anxiety, the effect of the D1 antagonist SCH23390 microinjected mainly close to the rostral intercalated islands in rats was studied, using the White and Black Box test. SCH23390 reduced anxiety by an increase in the latency of the first entry into the black compartment and by an increase in the total time spent in the white compartment of the White and Black Box test, while there was no significant modification of locomotion. It is suggested that blockade of D1 receptors in the rostral intercalated islands may reduce anxiety through a reduction of GABA-mediated dishinibition of the central amygdaloid nucleus.  相似文献   
30.
Keratin 19 and nuclear reactivity to an endogenous lectin, galectin-1, represent a potential marker of epidermal stem cells. We detected expression of keratin 19 and nuclear binding sites for galectin-1 in adult cells migrating from the hair follicle, where cells expressing keratin 19 are located in the bulge region. The results were compared with the expression of both markers in cells adhering from suspension prepared from the interfollicular epidermis without keratin-19-positive cells and with nuclear binding sites for galectin-1. The results were compared with data from basal cell carcinomas. All cells were analyzed concerning size, as it is known that cell diameter influences the clonogenic potential of keratinocytes. The major result of this study is the observation of transient expression of keratin 19 and nuclear galectin-1 binding sites in originally negative interfollicular epidermal cells induced by adhesion. These cells were very small in size, similar to basal cells of the interfollicular epidermis or the bulge region of the hair follicle. The influence of the suspension regimen on beta1-integrin expression, cell diameter and growth was also monitored. A population of cells highly positive for beta1 integrin of the same diameter as keratin-19-positive cells insensitive to induction of terminal differentiation by lack of anchorage was characterized. Cells of the same size were also observed in the keratin-19-positive cells of basal cell carcinomas. In conclusion, the expression of poor levels of differentiation induced by cell adhesion is transient. Also, keratin 19 expression should not be exclusively regarded as a marker of stem cell activity.  相似文献   
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