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151.
Mineo TC  Ambrogi V  Mineo D  Fabbri A  Fabbrini E  Massoud R 《Chest》2005,127(6):1960-1966
BACKGROUND: In patients with severe emphysema, bone mineral density (BMD) is reduced and the risk of osteoporosis is increased. STUDY OBJECTIVES: To identify the impact of lung volume reduction surgery on BMD. DESIGN: Prospective cohort study. SETTING: University hospital. PATIENTS AND INTERVENTIONS: Forty emphysematous patients, all receiving oral steroid therapy, underwent bilateral lung volume reduction surgery. Thirty similar patients, who refused the operation, followed a standard respiratory rehabilitation program. MEASUREMENTS: All subjects were evaluated pretreatment and 12 months posttreatment for respiratory function, nutritional status, and bone-related biochemical parameters. BMD was assessed by dual-energy radiograph absorptiometry. RESULTS: After surgery, we observed significant improvements in respiratory function (FEV1, + 18.8% [p < 0.01]; residual volume [RV], -29.6% [p < 0.001]; diffusing capacity of the lung for carbon monoxide [Dlco], + 21.6% [p < 0.01]) nutritional parameters (fat-free mass, + 6.0% [p < 0.01]), levels of bone-related hormones (free-testosterone, + 20.5% [p < 0.01]; parathormone, -11.2% [p < 0.01]), bone turnover markers (osteocalcin, -12.7% [p < 0.05]; bone-alkaline-phosphatase, -14.0% [p < 0.05]; beta-crosslaps, -33.6% [p < 0.001]), BMD (lumbar, + 8.8% [p < 0.01]; femoral, + 5.5% [p < 0.01]), and T-score (lumbar, + 21.0% [p < 0.01]; femoral, + 12.4% [p < 0.01]) with reduction in osteoporosis rate (50 to 25%). Nineteen patients who had undergone surgery were able to discontinue treatment with oral steroids. These subjects showed a more significant improvement in BMD (lumbar, + 9.6%; femoral, + 6.8%; p < 0.001) and T-score (lumbar, + 27.3%; femoral, + 14.3%; p < 0.001). The remaining 21 patients who had undergone surgery experienced significant improvement compared to respiratory rehabilitation subjects despite continued therapy with oral steroids (BMD: lumbar, + 4.5% vs -0.7%, respectively [p < 0.01]; femoral, + 2.7% vs -1.1%, respectively [p < 0.05]; T-score: lumbar, + 14 vs -2.1, respectively [p < 0.01]; femoral, + 7.4 vs -2.7, respectively [p < 0.01]). The increase in lumbar BMD was correlated with the surgical reduction of RV (p = 0.02) and with the increase in Dlco (p = 0.01) and fat-free mass (p = 0.01). CONCLUSIONS: Lung volume reduction surgery significantly improves BMD compared to respiratory rehabilitation therapy, even in patients requiring oral steroids. The increase in BMD correlates with RV, Dlco, and fat-free mass, suggesting that the restoration of respiratory dynamics, gas exchange, and nutritional status induces improvement in bone metabolism and mineral content.  相似文献   
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153.
PURPOSE: The following study was done to evaluate the therapeutic value of radiotherapy as an adjunct to surgery for rectal cancer patients. METHODS: One-hundred twenty-four patients underwent curative resection by one surgeon (RC) from 1982 to 1991. Forty patients received combined preoperative and postoperative (sandwich) radiotherapy, 30 patients received postoperative radiotherapy, and 54 patients were treated by surgery alone. During the study period sandwich radiotherapy was primarily offered as a free treatment option for patients with tumors which were believed to be transmurally invasive, whereas postoperative radiotherapy was an alternative therapeutic option offered to patients with tumor classified as Dukes B and C at histopathologic examination. RESULTS: Operative mortality was 2 percent in the sandwich radiotherapy group vs. 7 percent in the surgery alone group. After a median follow-up of 60 months, the actuarial locoregional recurrence rate at five years was 3 percent for the sandwich radiotherapy group compared with 18 and 30 percent for the postoperative radiotherapy and surgery alone groups, respectively (P =0.019). A multivariate analysis using the Cox model confirmed the favorable independent influence of sandwich radiotherapy on local tumor control, especially in distal tumors. The therapeutic benefit of sandwich radiotherapy translated into increased survival in the low-rectum Dukes B subgroup of patients. The actuarial five-year survival rates were 86 percent, 50 percent, and 28 percent in the sandwich radiotherapy, postoperative radiotherapy and surgery alone groups, respectively (P =0.05). CONCLUSIONS: Preoperative radiotherapy has a significant effect on the prognosis of rectal cancer patients.  相似文献   
154.
This work aimed at determining the ideal ischemia time in an in vitro ischemia-reperfusion model of spinal cord injury. Rat spinal cord slices were prepared and then exposed or not to oxygen deprivation and low glucose (ODLG) for 30, 45, 60, 75 and 90 minutes. Cell viability was assessed by triphenyltetrazolium (TTC), lactate dehydrogenase (LDH) release, and fluorochrome dyes specific for cell dead (ethidium homodimer) using the apotome system. Glutamate release was enzymatically measured by a fluorescent method. Gene expression of apoptotic factors was assessed by real time RT-PCR. Whereas spinal cord slices exposed to ODLG exhibited mild increase in fluorescence for 30 minutes after the insult, the 45, 60, 75 and 90 minutes caused a 2-fold increase. ODLG exposure for 45, 60, 75 or 90 minutes, glutamate and LDH release were significantly elevated. nNOS mRNA expression was overexpressed for 45 minutes and moderately increased for 60 minutes in ODLG groups. Bax/bcl-xl ratio, caspase 9 and caspase 3 mRNA expressions were significantly increased for 45 minutes of ODLG, but not for 30, 60, 75 and 90 minutes. Results showed that cell viability reduction in the spinal cord was dependent on ischemic time, resulting in glutamate and LDH release. ODLG for 45 minutes was adequate for gene expression evaluation of proteins and proteases involved in apoptosis pathways.  相似文献   
155.
The facial growth of Class III malocclusion worsens with age, in this case, the early orthopedic treatment, providing facial balance, modifying the maxillofacial growth and development. A 7.6-year old boy presented with Class III malocclusion associated with anterior crossbite; the mandible was shifted to the right and the maxilla had a transversal deficiency. Rapid maxillary expansion followed by facemask therapy was performed, to correct the anteroposterior relationship and improve the facial profile. The patient was followed for a 15-year period, after completion of the treatment, and stability was observed. Growing patients should be monitored following their treatment, so as to prevent malocclusion relapse.  相似文献   
156.
The aim of this study was to identify and characterize pituitary cells of Steindachneridion parahybae females in captivity, highlighting the possible relationship with reproductive disorders at this level, since this species shows oocyte final maturation, ovulation and spawning dysfunction in captivity. The localization and distribution of growth hormone (GH), prolactin (PRL), somatolactin (SL), β‐luteinizing hormone (β‐LH), and β‐follicle stimulating hormone (β‐FSH) immunoreactive (‐ir) cells in the adenohypophysis was studied by immunohistochemical and Western blot methods. In addition, cellular morphometric analyses and semi‐quantification of ir‐cells optical density (OD) during the annual reproductive cycle and after artificial induced spawning (AIS) were performed. Results showed that the distribution and general localization of pituitary cell types were similar to that of other teleost species. However, the morphometrical study of adenohypophysial cells showed differences along the reproductive cycle and following AIS. In general, females at the vitellogenic stage presented greater OD values for GH, PRL and SL than at other maturation stages (previtellogenic and regression stages), probably indicating an increased cellular activity during this stage. Conversely, β‐LH OD did not vary during the annual reproductive cycle. After AIS, β‐LH, SL and GH ir‐cells showed an increase in OD values suggesting a possible involvement on oocyte final maturation, ovulation and spawning or a feedback control on the brain‐pituitary‐gonads axis. Reproductive dysfunction in S. parahybae females in captivity may be due to alteration of the synthesis pathways of β‐LH. In addition, GH family of hormones could modulate associated mechanisms that influence the reproductive status in this species. Anat Rec, 298:1644–1658, 2015. © 2015 Wiley Periodicals, Inc.  相似文献   
157.
BackgroundPaediatricians rarely devote any time to screening and treatment for parental tobacco use. The present project is part of a Global Alliance against Chronic Respiratory Diseases (GARD)-Italy Demonstration Project, aimed to increase the skills of primary care physicians and paediatricians as “promoter of smoking cessation”. The aims of this study were: (I) to identify latent classes of barriers and incentives for smoking cessation counseling among paediatricians using latent class analysis (LCA); (II) to investigate risk factors for inclusion into the identified classes.MethodsIn 2018, 1,500 Italian paediatricians were invited to complete an online survey on passive smoke exposure in children. LCA was used to discover underlying response patterns, and to identify respondent groups with similar attitudes toward passive smoke exposure in children. Multinomial logistic regression helped investigate which explanatory variables influenced inclusion into a class. A P value <0.05 was considered significant.ResultsThe overall response rate was 71% (n=1,071/1,500). Three classes were identified: Class 1 “passive” (n=226, 21.10%); Class 2 “unmotivated” (n=124, 11.58%); and Class 3 “proactive” (n=721, 67.32%). Assuming Class 3 as reference, ever having been a smoker was borderline associated (P=0.052) with increased probability of inclusion into Class 1 (OR =1.43, 95% CI, 1.00–2.06). Having 6–15 or ≥15 years of work experience versus having less than five years was associated with decreased probability of being in the “passive” class (OR =0.46, 95% CI, 0.22–0.96 and OR =0.49, 95% CI, 0.27–0.87, respectively), as was discussing parents’ addiction to alcohol/drugs (OR =0.50, 95% CI, 0.33–0.76).ConclusionsWe identified three profiles among Italian paediatricians related to barriers and incentives for smoking cessation promotion. Tailored educational interventions for paediatricians are required to promote smoking cessation programs.  相似文献   
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159.
The trematode Schistosoma mansoni, an important parasite of humans, is the principle agent of the disease schistosomiasis. In the human host, one of the most important stress factors of this parasite is the oxidative stress generated by both the metabolism of the worm and the immune system of the host. The proteasomal system is responsible for protein homeostasis during oxidative stress. The 26S proteasome is a multicatalytic protease formed by two compartments, a 20S core and regulatory particle 19S, and controls the degradation of intracellular proteins, hence regulating many cellular processes. In the present report, we describe the biochemical characterization and role of the 20S proteasome in the response of adult S. mansoni worms exposed to hydrogen peroxide. Characterization of the response to the oxidative stress included the evaluation of viability, egg production, mortality, tegument integrity, and both expression and activity of proteasome. We observed decreases in viability, egg production as well as 100 % mortality at the higher concentrations of hydrogen peroxide tested. The main changes observed in the tegument of adult worms were peeling as well as the appearance of bubbles and a decrease of spines on the tubercles. Furthermore, there were increases in 26S activity to the same extent as 20S proteasome activity, although there was increase of 20S proteasome content, suggesting that degradation of protein oxidized in adult worms is due to the 20S proteasome. It was demonstrated that adult S. mansoni worms are sensitive to oxidative stress, and that a variety of processes in this parasite are altered under this condition. The work contributes to a better understanding of the mechanisms employed by S. mansoni to survive under oxidative stress.  相似文献   
160.
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