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951.
The treatment of multiple traumas in children requires knowledge of common injury patterns, incidence, mortality, and the consequences and differences between these injuries in children and adult patients. However, epidemiological studies concerning pediatric multiple trauma are rare. To address this, data were collected and analyzed from 682 multiple trauma patients treated at a Level I trauma center. The patients were divided into four age-related groups (< 6 years, 6-12 years, 13-18 years, and 18-40 years) and were evaluated for trauma mechanism, injury distribution, and cause of death. Children aged 6 to 17 years mostly were injured as pedestrians and cyclists whereas infants, preschoolers, and adults more commonly were injured as car passengers. Pediatric patients suffered a significantly higher mortality than adults, with a threefold increased risk of death when injured as passengers in car accidents. Injuries to the head and the legs were most common. A lower incidence of thoracic (28% versus. 62%), abdominal (20% versus 36%), pelvic (22% versus 35%), and upper limb (32% versus 43%) trauma was observed in children (< 18 years) than in adults (18-40 years). Nevertheless, trauma to the thorax, abdomen, and head were associated with a high risk of death in all groups. Spinal cord injuries, especially in the cervical region, also carried a high risk of mortality (36.8 in the group of patients younger than 18 years and 18.9 in the group of patients 18-40 years). Children younger than 6 years had the most severe head injuries. The data show that there are important differences in incidence, mortality, and injury patterns between pediatric and adult patients with multiple traumas.  相似文献   
952.
An unusual case of an intraneural ganglion cyst of the hypoglossal nerve is presented. Only one case of this rare clinical entity has been reported previously. A 51-year-old woman presented with a 6-month history of left-sided hypoglossal nerve palsy. Magnetic resonance imaging revealed a cystic lesion related to the hypoglossal canal. There was no enhancement of the lesion after administration of Gd. A high-resolution computerized tomography scan of the skull base demonstrated an enlargement of the hypoglossal canal. To access the lesion, a far-lateral endoscope-assisted microsurgical approach was used. An intraneural ganglion lesion invading the hypoglossal nerve was found and resected. A histopathological examination confirmed that the lesion was an intraneural ganglion cyst. The occurrence of an intraneural ganglion cyst at the hypoglossal nerve is very rare. This case exemplifies an atypical location of a synovial cyst with cranial nerve involvement.  相似文献   
953.
954.
955.
Load-related implant reaction of mini-implants used for orthodontic anchorage   总被引:11,自引:0,他引:11  
Abstract: The purpose of this study was to determine the clinical and biomechanical outcome of two different titanium mini‐implant systems activated with different load regimens. A total of 200 mini‐implants (102 Abso Anchor® and 98 Dual Top®) were placed in the mandible of eight Göttinger minipigs. Two implants each were immediately loaded in opposite direction by various forces (100, 300 or 500 cN) through tension coils. Additionally, three different distances between the neck of the implant and the bone rim (1, 2 and 3 mm) were used. The different load protocols were chosen to evaluate the load‐related implant performance. The load was provided by superelastic tension coils, which are known to develop a virtually constant force. Non‐loaded implants were used as a reference. Following an experimental loading period of 22 and 70 days half of the minipigs were sacrificed, and implant containing bone specimens evaluated for clinical performance and implant stability. Implant loosing was found to be statistically dependent on the tip moment (TM) at the bone rim. Clinical implant loosing were only present when load exceeded 900 cN mm. No movement of implants through the bone was found in the experimental groups, for any applied loads. Over the two experimental periods the non‐loaded implants of one type of implant had a higher stability than those of the loaded implants. Dual Top® implants revealed a slightly higher removal torque compared with Abso Anchor® implants. Based on the results of this study, immediate loading of mini‐implants can be performed without loss of stability when the load‐related biomechanics do not exceed an upper limit of TM at the bone rim.  相似文献   
956.
957.
BACKGROUND: In the Netherlands, 500,000 blood donors are active. Blood of all donors is currently typed serologically for ABO, the Rh phenotype, and K. Only a subset of donors is typed twice for a larger set of red cell (RBC) and/or platelet (PLT) antigens. To increase the direct availability of typed RBCs and PLTs, a high-throughput technique is being developed to genotype the whole donor cohort for all clinically relevant RBC and PLT antigens. STUDY DESIGN AND METHODS: A multiplex polymerase chain reaction was developed to both amplify and fluorescently label 19 gene fragments of RBC and PLT antigens in one reaction. To test the setup of the genotyping method by microarray, a pilot study with human PLT antigen (HPA)-typed donor samples was performed. On each slide, 12 arrays are present containing 20 probes per PLT antigen system (28 for HPA-3). The allele-specific oligohybridization method was used to discriminate between two different alleles. RESULTS: Two blinded panels encompassing 94 donors were genotyped for HPA-1 through -5 and -15; no discrepancies were found compared to their serologic typing (HPA-1, -2, -3, -4, and -5) and genotyping (HPA-15; TaqMan, Applied Biosystems). CONCLUSION: This study shows that the HPA microarray provides a reliable and fast genotyping procedure. With further development an automated throughput for complete typing of large donor cohorts can be obtained.  相似文献   
958.
BACKGROUND: Patients with cancer are characterized by a profound impairment of glucose utilization, with lipids being the preferred metabolic fuel. In contrast, the energy needs of malignant tumors are almost entirely met by glucose. We therefore studied the effects of a high-fat diet, particularly on body composition. PATIENTS AND METHODS: Twenty-three moderately malnourished patients with gastrointestinal carcinomas were randomized to receive either a conventional diet supplying 35 nonprotein kcal and 1.1 g of protein/kg per day (group A, n = 11) or a fat-enriched artificial liquid diet (20 nonprotein kcal/kg per day) plus normal meals (group B, n = 12) for a period of eight weeks, i.e., from the first to the third chemotherapy cycle. The fat content of the artificial diet was 66% of the nonprotein calories. The day before the nutritional interventions, and again after four and eight weeks, body compartments were determined using bioelectrical impedance analysis, lymphocyte subpopulations were quantified using flow cytometry, and some aspects of the quality of life were rated using four linear analog self-assessment (LASA) scales. The statistical calculations were done as an exploratory data analysis. RESULTS: The consumption of non-protein calories did not differ significantly between the two patient groups. An average weight gain in group B contrasted with an average weight loss in group A after four (P < 0.01) and eight weeks (P < 0.05). Fat-free mass showed an intergroup difference in favor of group B after eight weeks (P < 0.05). Body cell mass was maintained throughout the study in group B, but declined significantly up to weeks 4 and 8 in group A (intergroup difference: P < 0.05 and 0.01, respectively). A decrease in the total lymphocyte count by 559 cells/mul occurred with the fat-enriched diet (P < 0.05). Several aspects of the quality of life were rated to be better in group B than in group A, although not all differences reached statistical significance. CONCLUSION: In patients with cancer, a high-fat diet may possibly support the maintenance of both body weight and body cell mass. However, monitoring the lymphocyte count is advisable.  相似文献   
959.
BACKGROUND: The objective of this study was to investigate the effect of a specific endothelin(A) receptor antagonist (ET(A)-RA) on mRNA expression of genes encoding vasoactive mediators and proinflammatory cytokines and on the microhemodynamics (assessed by measurement of laser Doppler flow and tissue blood gases) following complete vascular exclusion of the porcine liver. STUDY DESIGN: Sixteen adult German landrace pigs were subjected to 120 min of warm hepatic ischemia by total vascular exclusion. To avoid portal congestion, a passive porto-femoro/jugular bypass was implanted. The animals were divided into 2 groups: the control group received saline solution and the therapy group was given the selective ET(A)-RA BSF 208075. Hepatic microcirculation was evaluated by p(O(2)) and p(CO(2)) measurement with the Paratrend sensor and by laser Doppler flow measurement. Liver tissue samples were collected 1 h after reperfusion and quantitative mRNA expression for prepro-ET-1, pro-IL-1beta, pro-IL-6, pro-TNF-alpha, eNOS was analyzed using the TaqMan system. Additionally, immunohistochemical analysis using a semiquantitative score for ET-1 was performed. Postischemic liver damage was monitored by measurement of liver enzymes and assessed by histological analysis using a semiquantitative scoring classification. RESULTS: Partial oxygen pressure in the hepatic tissue and laser Doppler flow were significantly improved in the therapy group. One hour after reperfusion, quantitative RT-PCR revealed significantly lower expression of prepro-ET-1, eNOS, pro-TNF-alpha, and pro-IL-6 in the therapy group compared to controls. Immunohistochemical analysis demonstrated significantly reduced ET-1 immunostaining after therapy. Furthermore, blockade of ET(A) receptors prevents tissue damage. CONCLUSIONS: Treatment with the selective ET(A)-RA BSF 208075 has protective effects on microcirculation after 120 min liver ischemia and reperfusion. The authors were able to show that ET(A)-RA not only affects the expression of vasoactive genes, but also decreases gene expression of proinflammatory cytokines such as TNF-alpha and IL-6.  相似文献   
960.
The effect of enzyme inhibitors on histamine catabolism in man   总被引:2,自引:1,他引:1       下载免费PDF全文
The catabolism of histamine was studied in three female psychiatric patients by analysis of the [14C]-labelled metabolic products occurring in the urine after a subcutaneous injection of [14C]histamine. Each patient was studied before and during treatment with aminoguanidine or iproniazid.

Without treatment the patients had a normal histamine catabolism. Aminoguanidine and iproniazid inhibited the oxidation of histamine to imidazoleacetic acid; iproniazid produed a 50% inhibition of the oxidation of methylhistamine to methylimidazoleacetic acid. After iproniazid a large proportion of the injected [C14]histamine was excreted as methyl [14C]histamine.

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