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991.
According to the World Health Organization, hemangiomas are benign vasoformative neoplasms or developmental conditions of endothelial origin. The body region is the most commonly affected part of the mandible, and only 4 cases of condylar tumors have been reported in the literature to date. The differential diagnosis between high and low flow vascular lesions is crucial for successful treatment, decreasing the occurrence of serious intraoperative hemorrhage. The clinical, radiographic, and pathological features of an intraosseous vascular lesion in the mandibular condyle in a 22-year-old male are presented, and the differential diagnostic aspects between hemangioma, vascular malformation, and high or low flow lesions are discussed.  相似文献   
992.
Abstract:  Introduction:  Peri-implant pathologies consist of an inflammatory process affecting the soft and hard tissues surrounding the implants. Chlorhexidine is considered the gold standard antiseptic, with a large variety of choice in administration. In this study, a protocol for the irrigation of peri-implant pockets with a chlorhexidine gel, using a plastic needle for the delivery of the product into the peri-implant pockets is described. Study participants and methods:  Nine patients with at least one implant presenting peri-implant pathology (inflamed soft tissue associated with bone loss around the implant) were enrolled in this prospective clinical study, and followed-up for 1 year, where clinical parameters such as modified plaque index, modified bleeding index, probing pocket depths, attachment levels were assessed at baseline, 1 month, and 1 year after implementation of the treatment protocol. Results:  Treatment success was achieved in eight of the nine patients (and in 11 of the 13 implants) according to the success criteria adopted by the authors of this study. Discussion:  Infection control lies at the heart of peri-implant treatment. The control of three factors such as optimal diagnosis, removal of the aetiological factor of the disease (proper removal of debris and decontamination of the peri-implant sulcus/pocket) and a good patient's oral hygiene self-care represents the key to success, resulting in good treatment outcomes when managing peri-implant pathologies. The protocol used (irrigation of peri-implant pockets with chlorhexidine gel delivered by a plastic needle) is considered to be of utility.  相似文献   
993.
Rhabdomyosarcoma (RMS) is a malignant soft tissue neoplasm consisting of cells derived from the primitive mesenchyme that exhibit a profound tendency to myogenesis. About 35% of RMS arises in the head and neck, being classified as parameningeal and non-orbital non-parameningeal forms. Parameningeal tumors carry the worst prognosis. The use of contemporary, multi-agent chemotherapy, radiotherapy, and surgery has made treatment of the disseminated disease possible, and has significantly improved overall survival from 25% in 1970 to 70% in 1991. Here, we present the management of two cases of orofacial RMS in adolescents: an 18-year-old, white female that had a 9-month history of a nodule in the left buccal mucosa, and a 19-year-old, white male who had been aware of a nodule in the left, posterior maxillary ridge with progressive growth for 4 months. Before final diagnosis, both cases were previously treated as inflammatory lesions. Their clinicopathological aspects, treatment, and poor survival as a consequence of delays in diagnosis are discussed.  相似文献   
994.
Resistance of Plasmodium falciparum to drugs such as chloroquine and sulfadoxine-pyrimethamine is a major problem in malaria control. Artemisinin (ART) derivatives, particularly in combination with other drugs, are thus increasingly used to treat malaria, reducing the probability that parasites resistant to the components will emerge. Although stable resistance to artemisinin has yet to be reported from laboratory or field studies, its emergence would be disastrous because of the lack of alternative treatments. Here, we report for the first time, to our knowledge, genetically stable and transmissible ART and artesunate (ATN)-resistant malaria parasites. Each of two lines of the rodent malaria parasite Plosmodium chabaudi chabaudi, grown in the presence of increasing concentrations of ART or ATN, showed 15-fold and 6-fold increased resistance to ART and ATN, respectively. Resistance remained stable after cloning, freeze-thawing, after passage in the absence of drug, and transmission through mosquitoes. The nucleotide sequences of the possible genetic modulators of ART resistance (mdr1, cg10, tctp, and atp6) of sensitive and resistant parasites were compared. No mutations in these genes were identified. In addition we investigated whether changes in the copy number of these genes could account for resistance but found that resistant parasites retained the same number of copies as their sensitive progenitors. We believe that this is the first report of a malaria parasite with genetically stable and transmissible resistance to artemisinin or its derivatives.  相似文献   
995.
996.
BACKGROUND: Thiopurine S-methyltransferase (TPMT) is an enzyme involved in the normal metabolic inactivation of thiopurine drugs. Patients with intermediate or no TPMT activity are at risk of toxicity after receiving standard doses of thiopurine drugs and it was shown that inter-individual differences in response to these drugs is largely determined by genetic variation at the TPMT locus. OBJECTIVE: This study was designed to investigate in the Sardinian population the frequency distribution of four of the most common variants accounting for TPMT deficiency and to conduct comparative analyses with other populations in order to obtain insights into the main factors that have shaped diversity at the TPMT locus in Sardinia. METHODS: DNA was extracted in 259 Sardinians and the frequencies of allelic variants of TPMT were determined using polymerase chain reaction-restriction fragment length polymorphism technique. RESULTS: Among the 259 Sardinians genotyped, 6.95% were found to be heterozygous for one of four TPMT variants screened; for each variant the frequency estimate was 1.74%, 0.58%, 0.39% and 0.77% for TPMT*2, TPMT*3A, TPMT*3B and TPMT*3C respectively. CONCLUSIONS: Although Sardinia does not show reduced diversity at the TPMT locus, the spectrum of TPMT allele frequencies affords evidence of remarkable influence of genetic drift and founder effects throughout its population history. In the broad context of the European TPMT diversity, the Sardinians come out as outliers, an observation consistent with previous genetic inferences that Sardinia has features of a genetic isolate.  相似文献   
997.
A new combined methodology consisting of direct observation and two types of interviews (internal and external interviews) was evaluated for use in exposure risk assessment in schistosomiasis. Specific objectives were to determine its usefulness in achieving equitable coverage of gendered exposure risk and its efficiency in identifying water contact behavior in a rural area in Brazil with different settlement patterns, land use and domestic water supplies. Of the 2476 water contacts recorded, 1223 (49.4%) were identified by direct observation, 946 (38.2%) by internal interviews and 307 (12.4%) by external interviews. Significantly longer mean durations of contacts were recorded for females and greater mean percentage of body surface exposed for males (P<0.01), reflecting differences in gendered water contact activities. Direct observation identified slightly more male contacts, external interviews significantly more male contacts (P<0.006), and internal interviews moderately more female contacts. The three methods recorded mean numbers of contacts and mean TBM (total body minutes) per person, declining with age. Significant differences were found between the three methods in regard to frequency and/or intensity of washing clothes, fetching water, washing utensils, washing multiple parts of the body, and bathing. The three methods also recorded differentially frequencies and exposure intensities in the three study communities, among different age groups, by gender and for individual study members. These activity-, locality-, age/gender- and person-specific patterns reflect the relative efficiency and complementarity of the three methods in settlements with different land use, access to streams and water supplies.  相似文献   
998.
BACKGROUND: Idiopathic adolescent scoliosis (AIS) causes not only spinal deformities but rib cage abnormalities that lead to abnormal volumes and pulmonary capacity on pulmonary function testing (PFT). The objective of this study was to analyze the impact of a physical rehabilitation program on respiratory function in surgical patients with AIS. METHODS: From October 2003 to October 2004, a total of 34 patients (age range, 10 to 18 years) presenting with AIS and a thoracic curvature between 45 degrees and 88 degrees were studied prospectively at a tertiary academic hospital. The patients underwent clinical and radiographic evaluations of the vertebral deformity, chest radiographs, PFT, evaluation of peak expiratory flow, and 6-min walk tests (6MWTs) before and after joining a physical rehabilitation program for 4 months. RESULTS: An improvement in FVC, inspiratory capacity, FEV(1), expiratory reserve volume, and performance assessed by 6MWT were observed after rehabilitation. CONCLUSIONS: Global conditioning improved after the rehabilitation program. This was expressed by both PFT and 6MWT results.  相似文献   
999.
OBJECTIVE: Antiphospholipid antibodies are associated with increased risk of thrombosis, particularly as in antiphospholipid syndrome. This study aims to determine the acute effects of anticardiolipin antibodies on nitric oxide production and vascular function. METHODS: Ex vivo aortic rings from male Sprague Dawley rats were incubated with IgG monoclonal anticardiolipin antibody (IS4) or a non-specific IgG control. In organ baths, response to phenylephrine and acetlycholine was determined alone and with nitro-L-arginine methyl ester (L-NAME), 1,400 W, D-arginine, L-arginine, sodium nitroprusside and cardiolipin. In vivo antibodies were injected into anaesthetised, spontaneously breathing male Sprague Dawley rats. Haemodynamic variables and serum nitric oxide were measured. Immunohistochemistry for iNOS and eNOS was performed in kidney vessels. RESULTS: Phenylepherine contraction was decreased in the IS4 group compared to controls (p < 0.001). L-NAME, 1,400 W and cardiolipin, abolished this effect. L-Arginine caused significant relaxation in the IS4 group (p = 0.005). Mean arterial pressure in rats injected with IS4 was reduced compared to IgG and saline controls (p < 0.001). NO in plasma increased significantly after IS4 administration (p < 0.001). Immunohistochemistry showed increased iNOS expression in kidney arteries in the IS4 group, with no change in eNOS. CONCLUSION: Anticardiolipin antibodies induce NO production acutely via increased expression of iNOS in both ex vivo and in vivo models.  相似文献   
1000.
We performed a retrospective study of 164 human immunodeficiency virus (HIV)-infected patients with disseminated histoplasmosis to identify the risk factors for death. Death occurred in 32% of the cases. Univariate analysis identified the following risk factors: diarrhea (odds ratio [OR] = 3.9, P = 0.001), neurologic manifestations (OR = 5.8, ; P = 0.001), hemoglobin level < 8.0g/dL (OR = 2.7, P = 0.004), urea level 2 times the normal upper limit (OR = 5.0, P < 0.001), creatinine level > 1.5 mg/dL (OR = 2.9, P = 0.005), aspartate aminotransferase (AST) level > 2.5 times the normal upper limit (OR = 3.1, P = 0.01), respiratory insufficiency (OR = 9.7, P < 0.001), sepsis (OR = 20.2, P < 0.001), and acute renal failure (OR = 2.5, P = 0.011). A hemoglobin level < 8.0 g/dL (OR = 3.8, P = 0.008), an AST level >or= 2.5 times the normal limit (OR = 1.0, P = 0.007), acute renal failure (OR = 2.96, P = 0.015), and respiratory insufficiency (OR = 12.2, P = 0.01) were independent risk factors for death.  相似文献   
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