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81.
The purpose of the study was to compare the performance of full-field digital mammography (FFDM) with soft-copy reading to screen film mammography (SFM) used during the first prevalent 2-year round of population-based screening. A total of 18,239 women aged 50–69 years were screened with FFDM as part of the Norwegian Breast Cancer Screening Programme (NBCSP). Process indicators were compared to data from 324,763 women screened with SFM using the common national database of the NBCSP. The cancer detection rates were 0.77% (140/18,239) for FFDM and 0.65% (2,105/324,763) for SFM (p = 0.058). For ductal carcinoma in situ (DCIS) alone, the results were: FFDM 0.21% (38/18,239) compared to SFM 0.11% (343/324,763) (p < 0.001). Recall rates due to positive mammography were for FFDM 4.09% (746/18,239), while for SFM 4.16% (13,520/324,764) (p = 0.645), due to technically insufficient imaging: FFDM 0.22% (40/18,239) versus SFM 0.61% (1,993/324,763) (p < 0.001). The positive predictive value (PPV) in the FFDM group was 16.6% (140/843), while 13.5% (2,105/15,537) for SFM (p = 0.014). No statistically significant differences were recorded concerning histological morphology, tumour size, or lymph node involvement. In conclusion FFDM had a significantly higher detection rate for DCIS than SFM. For invasive cancers no difference was seen. FFDM also had a significantly higher PPV and a significantly lower technical recall rate.  相似文献   
82.
This study investigates the hypothesis that the integrity of the cartilage hinge at the distal humeral epiphysis determines the stability of fractures of the lateral humeral condyle. Sixteen patients with lateral humeral condyle fractures were studied with radiographs and magnetic resonance imaging (MRI). The clinical course of each patient was compared using these imaging studies to determine whether initial fracture displacement and the integrity of the cartilage hinge correlated with fracture stability. Radiographically, 4 fractures were considered unstable (with initial fracture displacement >3 mm) and 12 were stable (initial displacement < or =3 mm). On MRI, 6 fractures were complete (with disruption of the lateral cartilage hinge) and 10 were incomplete. All unstable fractures had complete fractures on MRI. Ten of the 12 patients with radiographically stable injuries had incomplete fractures on MRI. None of these displaced during treatment. Two patients had radiographically stable fractures and complete fractures on MRI. One of these fractures displaced, confirming the hypothesis that the stability of lateral humeral condyle fractures is related to the integrity of the cartilage hinge.  相似文献   
83.
Periods of reduced joint loading have been shown to induce changes in the biochemical composition. metabolism and mechanics of articular cartilage. In this study, changes in cartilage swelling behavior were studied following a 4-week period of joint immobilization, using a recently developed osmotic loading technique [J. Biomech, 32 (1999) 401-408]. The magnitude and distribution of swelling strains were measured in cartilage-bone samples equilibrated in physiological and hypotonic saline, relative to a hypertonic reference NaCl solution. Physicochemical parameters (glycosaminoglycan fixed charge density and water volume fraction) were determined in site-matched cartilage samples. The experimental data for swelling strains, fixed charge density and water volume fraction were used with a triphasic mechano-chemical theory [J. Biomech. Eng. 113 (1991) 245-258] to determine the effect of joint immobilization on the tensile modulus of the cartilage solid matrix. Four weeks of immobilization resulted in a significant increase in the magnitude of swelling-induced strains, and a significant decrease in fixed charge density in cartilage, as compared with the contralateral controls. Joint immobilization also resulted in decreases in values for the modulus of cartilage, as compared with the contralateral controls. Our results suggest that 4 weeks of joint immobilization had a significant effect on cartilage mechanical function that may be linked to collagen changes in the cartilage extracellular matrix.  相似文献   
84.
We examined the distribution of quantitative heel ultrasound (QUS) parameters in population samples of European men and looked at the influence of lifestyle factors on the occurrence of these parameters. Men aged between 40 and 79 years were recruited from eight European centers and invited to attend for an interviewer-assisted questionnaire, assessment of physical performance, and quantitative ultrasound (QUS) of the calcaneus (Hologic; Sahara). The relationships between QUS parameters and lifestyle variables were assessed using linear regression with adjustments for age, center, and weight. Three thousand two hundred fifty-eight men, mean age 60.0 years, were included in the analysis. A higher PASE score (upper vs. lower tertile) was associated with a higher BUA (β coefficient = 2.44 dB/Mhz), SOS (β = 6.83 m/s), and QUI (β = 3.87). Compared to those who were inactive, those who walked or cycled more than an hour per day had a higher BUA (β = 3.71 dB/Mhz), SOS (β = 6.97 m/s), and QUI (β = 4.50). A longer time to walk 50 ft was linked with a lower BUA (β = ?0.62 dB/Mhz), SOS (β = ?1.06 m/s), and QUI (β = ?0.69). Smoking was associated with a reduction in BUA, SOS, and QUI. There was a U-shaped association with frequency of alcohol consumption. Modification of lifestyle, including increasing physical activity and stopping smoking, may help optimize bone strength and reduce the risk of fracture in middle-aged and elderly European men.  相似文献   
85.
PURPOSE: The effect of methylphenidate (MPH) on inhibitory control as assessed by the stop task in children with attention-deficit/hyperactivity disorder (ADHD) could be influenced by task difficulty and may be mediated by attention. SUBJECTS AND METHODS: Fifteen children with ADHD performed the stop and the change task after placebo, 0.5 and 1.0 mg/kg MPH in a within-subject design. RESULTS: Linear-trend analysis showed a similar effect of MPH in both tasks and a stronger effect for inhibitory control than for attention. Furthermore, a correlation was found between blood serum metabolites of norepinephrine and dopamine for attentional measures and inhibitory control measures, respectively. DISCUSSION AND CONCLUSION: In children with ADHD MPH could act primarily on inhibitory control, and is not influenced by task difficulty. Also, attention and inhibitory control could have differential pharmacological profiles.  相似文献   
86.
87.
Littoral cell angioma is a rare splenic tumor which develops from specialised endothelial cells of the splenic red pulp. Numerous papers published since 1991 when the tumor was firstly described till now were focused on the radiologic characteristics of the lesion. This paper presents the clinical, imaging and morpho-immunohistochemical features of a littoral cell angioma diagnosed in a 51 year - old woman, to our knowledge, the first documented case in the Romanian medical literature. The lesion might be suspected on the basis of the clinical and imaging signs, but the diagnosis of certitude is provided by the gross and microscopic examination supplemented with immunohistochemical methods.  相似文献   
88.
When a professional athlete injures an elbow or shoulder, the uninjured joint must receive as much attention as the injured joint. Is there a relationship between injury of one joint and subsequent injury of the other joint? In the prospective study reported here, we created a database (a) to determine whether injury to one joint was more likely to result in a problem with the other joint and (b) to analyze for trends and correlations. A survey was administered to all pitchers on a professional baseball team to collect data about shoulder and elbow problems during their careers. Eighty-four pitchers (737 seasons of experience, 52 index injuries) were evaluated. Of the injured players, 27 were treated surgically. Risk for later injury was 4.6 times larger for players who had an index surgery than for those who had not. Of the players who had ulnar collateral ligament (UCL) reconstruction, 42% later sustained a shoulder injury. No player with rotator cuff surgery sustained a subsequent elbow or shoulder injury. There were significantly more upper extremity injuries with right-handed throwers. An elbow injury was more likely to result in shoulder problems, specifically after UCL reconstruction. Players who required surgery were almost 5 times more likely to have a later injury or surgery than players who did not require surgery.  相似文献   
89.
90.
OBJECTIVE: To determine whether extended transthoracic esophagectomy for adenocarcinoma of the mid/distal esophagus improves long-term survival. BACKGROUND: A randomized trial was performed to compare surgical techniques. Complete 5-year survival data are now available. METHODS: A total of 220 patients with adenocarcinoma of the distal esophagus (type I) or gastric cardia involving the distal esophagus (type II) were randomly assigned to limited transhiatal esophagectomy or to extended transthoracic esophagectomy with en bloc lymphadenectomy. Patients with peroperatively irresectable/incurable cancer were excluded from this analysis (n = 15). A total of 95 patients underwent transhiatal esophagectomy and 110 patients underwent transthoracic esophagectomy. RESULTS: After transhiatal and transthoracic resection, 5-year survival was 34% and 36%, respectively (P = 0.71, per protocol analysis). In a subgroup analysis, based on the location of the primary tumor according to the resection specimen, no overall survival benefit for either surgical approach was seen in 115 patients with a type II tumor (P = 0.81). In 90 patients with a type I tumor, a survival benefit of 14% was seen with the transthoracic approach (51% vs. 37%, P = 0.33). There was evidence that the treatment effect differed depending on the number of positive lymph nodes in the resection specimen (test for interaction P = 0.06). In patients (n = 55) without positive nodes locoregional disease-free survival after transhiatal esophagectomy was comparable to that after transthoracic esophagectomy (86% and 89%, respectively). The same was true for patients (n = 46) with more than 8 positive nodes (0% in both groups). Patients (n = 104) with 1 to 8 positive lymph nodes in the resection specimen showed a 5-year locoregional disease-free survival advantage if operated via the transthoracic route (23% vs. 64%, P = 0.02). CONCLUSION: There is no significant overall survival benefit for either approach. However, compared with limited transhiatal resection extended transthoracic esophagectomy for type I esophageal adenocarcinoma shows an ongoing trend towards better 5-year survival. Moreover, patients with a limited number of positive lymph nodes in the resection specimen seem to benefit from an extended transthoracic esophagectomy.  相似文献   
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