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81.
An anatomical study of 50 fresh adult human cadavers was performed in order to verify prevalence of Galen's anastomosis (GA) and to evaluate whether factors such as gender, ethnicity, side of the neck, and individual stature may interfere with GA prevalence. The results were analysed using the Chi-square test, Student t-test, and F-Snedecor test. GA was observed in 87 of 100 dissections. There was no statistically significant difference regarding GA prevalence between groups separated by ethnicity (p = 0.853), gender (p = 0.198), side of the neck (p = 0.766), or individual height (p = 0.199). Therefore, the GA was a frequent anatomical finding, and this result was not influenced by any studied factor. Comparing our data with previous studies, we also concluded that the GA seems to play an important role in the innervation of the larynx, even though its function remains unclear. Also, it is reasonable to consider GA a constant anatomical constituent.  相似文献   
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Introduction The study analyzes and interprets possible effects of the COVID-19 pandemic on the preterm birth rate. Research questions included: were there fewer preterm births in Berlin in 2020, the first year of the pandemic, compared to the three years before the pandemic? Were there differences in preterm birth rates grouped according to weeks of gestation? Method The perinatal data of all singleton pregnancies were evaluated with regard to birth rates in Berlin, and the numbers of preterm neonates born in the three pre-pandemic years from 2017 to 2019 were compared to the rate for 2020, the first year of the pandemic. Results The overall number of singleton pregnancies born in maternity hospitals and labor wards in Berlin decreased in the first year of the pandemic. The percentage of preterm neonates born before 37 + 0 weeks of gestation (GW) was significantly lower in 2020 compared to the three previous years, with significantly more preterm neonates born before 28 + 0 GW and significantly fewer preterm neonates born between 28 + 0 to 35 + 0 GW. In 2020, significantly fewer neonates born before 37 + 0 weeks of gestation were delivered by primary caesarean section. The incidence of induced births was approximately the same. Conclusions In the first year of the pandemic, a range of social, iatrogenic, and biological factors may have had an impact on preterm birth rates. A Germany-wide evaluation of perinatal data across different German federal states for the period 2020 to 2022 would offer the opportunity to identify the causes of this lower rate of preterm births and determine whether conclusions can be drawn from this which would affect future strategies to reduce preterm birth rates.  相似文献   
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ObjectivesAssess associations between medical students’ reflective ability demonstrated in written narratives, and communication skills demonstrated later in simulated-patient breaking bad news interactions.MethodsWe analyzed 66 medical students’ reflective ability, using ‘REFLECT’ rubric and four newly developed parameters: Noticing Explanations provided to patients, Noticing Emotions, Remoteness/Connectedness in their writing, and mentioning Self-Emotions. ‘BAS’ and ‘SPIKES’ questionnaires measured students’ communication skills. Spearman and Chi-square tests examined correlations among all variables. Multiple regressions examined associations between reflective ability and demographic variables with communication skills.ResultsSignificant positive correlations between students’ reflective ability, measured by REFLECT and three of the new parameters, and global communication skill scores. Reflective ability of Noticing Explanations in writing was associated with ability to tailoring information to patients’ needs and address emotions.ConclusionsHigh reflective ability may improve communication skills. Specifically, ability to notice explanations to patients may enhance later capability to tailor information to patients and address emotions empathically.Practice implicationsEncourage educational interventions enhancing reflective ability; specifically observation and detailed writing about how explanations are given to patients and patients’ reactions to them. This process may help students develop competency to share and tailor difficult information sensitively—a critical skill when communicating bad news.  相似文献   
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Olfactory neurons in the nasal mucosa have the capacity to regenerate continuously along the lifespan by neurogenesis processes starting with progenitor cells close to the basal lamina. The cellular turnover into olfactory neuroepithelium may be modified by environmental stimuli insofar as nasal mucosa is directly in contact with airborne chemicals. However, few studies have been focused on selective changes, especially those concerning mature olfactory neurons and basal cells during specific inhalation exposure. Among chemicals, solvents are known to induce changes in smell abilities and concomitant histological and cellular modifications related to the type of molecule, concentration and time of exposure.This study was designed to characterize smell sensitivity (using behavioral tests) and immunohistochemical effects on olfactory neuroepithelium induced by pyridine exposure in mice. Olfactory marker protein (OMP) and proliferating cell nuclear antigen (PCNA) were used to characterize respectively mature olfactory neurons and basal cells. Results showed that inhalation exposure to pyridine had no impact on smell sensitivity whatever the concentration used and the time of exposure. These findings were in agreement with immunohistochemical measurements showing the same cellular kinetic whatever the condition of exposition to pyridine. Indeed, OMP-positive cells increased and PCNA-positive cells decreased as early as the beginning of exposure and cell amounts remained stable at this level until the end of exposure. These findings suggest that pyridine could have the property to rapidly activate a cellular turnover from basal cell progenitors. Rather than toxic effects, the present findings suggest that the metabolites of pyridine might have cell cycle activation properties.  相似文献   
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Aim

The aim of our study was to describe right atrial (RA) and right ventricular (RV) function, assessed by Doppler tissue imaging and 2D speckle tracking echocardiography (2DSTE), in women with signs of early impaired left ventricular diastolic function (DD).

Methods and Results

In a cross‐sectional trial, standard parameters of diastolic and right heart function were investigated in 438 women of the Berlin Female Risk Evaluation (BEFRI) study. In a subset of women, average peak systolic RA strain (RAS), as well as the average peak systolic RV strain of the free wall (RVS free wall) and of all RV segments (average RV strain; RVS Avg), was analyzed using 2DSTE. Compared to women with normal diastolic function (DD0), RAS, RVS free wall and RVS Avg were significantly reduced in DD (43.1% ± 11.9%, ?26.7% ± 5.6%, and ?23.3% ± 3.5% in DD0; vs 35.1% ± 10.4%, ?23.9% ± 5.5%, and ?20.6% ± 3.8% in DD; P < .01). Peak RV myocardial velocity (RV‐IVV) and acceleration during isovolumetric contraction (RV‐IVA) were markedly higher in DD (15.0 ± 3.9 cm/s and 3.1 ± 1.0 m/s² in DD vs 11.9 ± 3.2 cm/s and 2.8 ± 0.8 m/s² in DD0; P < .05). RAS and RV‐IVV were significantly associated with DD after adjustment to age, BMI, and left atrial strain in multivariate regression analysis.

Conclusion

Systolic right heart function is significantly altered in DD. DTI as well as 2DSTE constitute sensitive echocardiographic tools that enable the diagnosis of impaired right heart mechanics in early‐staged DD.  相似文献   
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Peripheral blood stem cells (PBSCs) used for allogeneic transplantation are collected by apheresis after pre‐treatment of donors with G‐CSF. Using modern apheresis devices stem cells can be collected more efficiently. It was studied whether collection on the 4th instead of the 5th day after initiation of G‐CSF treatment might be feasible. Stem cell yields that could have been collected on day 4 were calculated in two cohorts treated with 10 µg/kg G‐CSF once daily (n = 106, cohort I) or 5 µg/kg twice daily schedule (n = 85, cohort II). Harvests were predicted using the median collection efficiency (CE) of the apheresis machine and regarded successful when > 5.0 x106 CD34+/kg recipient body weight. Successful harvests at day 4 could have been obtained in only 22.6% and 41.2% of donors in cohort I and II respectively, while the expected successful collections on day 5 were 55.7% and 76.5%. Individual donor factors that correlated with a successful harvest on day 4 were weight, BMI, age, ratio donor/recipient weight and total G‐CSF dose in cohort I, whereas ratio donor/recipient weight was the only significant predictor in cohort II. Donor weight, BMI and total G‐CSF dose correlated positively with CD34+ values in the blood on day 4 in all donors. However, donor characteristics were not able to be used as strong predictors in daily practice. In conclusion, PBSC collection on day 4 will not result in a successful harvest in most stem cell donors, however using a twice daily G‐CSF scheme increases the yield.  相似文献   
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