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71.
Implantation represents the limiting step in governing reproductive outcomes. The process is driven by both embryo and endometrium alike. Minute perturbations in this orchestration lay foundation for pregnancy-associated complications that may manifest throughout the gestational course. Furthermore, placental function dictates many aspects of fetal development inclusive of preeclampsia and intrauterine growth restriction (IUGR). Novel techniques such as Multigate Spectral Doppler Analysis (MSDA) may allow for early detection and diagnosis of potentially deleterious fetal outcomes.  相似文献   
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OBJECTIVES: To evaluate the determinants of tubal rupture in women who suffered from ectopic pregnancy in relation to their demographic profile and medical history. STUDY DESIGN: This retrospective observational clinical study was conducted in five general hospitals in Vilnius, Lithuania. The population was composed of 879 women with surgically proven ectopic pregnancy. Tubal rupture was diagnosed at the time of surgery. Univariate and multivariate logistic regression analyses were performed to identify the risk factors for tubal rupture. RESULTS: The occurrence of tubal rupture was 29.5% (259/879). It was encountered significantly more often in women with age of > or =35 years (odds ratio 1.9 [1.3-2.8]). Patients whose EP was located in the isthmus were at higher risk of having tubal rupture (odds ratio 3.2 [2.2-4.5]) while known risk factors for EP were not associated with an elevated risk. CONCLUSIONS: Our data suggest that age of > or =35 years and implantation in the straightest segment of the tube could be associated with increased rate of tubal rupture. Of particular interest is the overall tubal rupture prevalence (29.5%) observed since these women were managed in an environment where transvaginal ultrasound equipment and quantitative assessment of beta-human chorionic gonadotrophin were not routinely available.  相似文献   
73.
AIM: Placental insufficiency is a pathological condition consisting of a placental functional deficit with multifactorial etiology; it can cause maternal complications such as edema, proteinuria, hypertension, etc. Our study aims to establish if placenta analysis after birth can lead to the identification of basic morphological alterations which can be easily documented and useful for the diagnosis of feto-neonatal pathologies. METHODS: We examined 60 pregnant women (45 primipara, 15 multipara). They were hospitalized in the period from March 1998 to March 2004 in different pregnancy periods because of fetus growth delay. After birth, a careful examination of the placenta has been carried out soon after spontaneous birth (weight, thickness, possible morphological alterations which could be macroscopically observed) and it was followed by an anatomo-pathological examination carried out at the Anatomopathology Unit of Ospedali Riuniti in Foggia. RESULTS: Macroscopic examination, in the group of women at the first pregnancy, showed that there were no morphological alterations in the placenta in all the cases, but the weight was normal (400- 500 g) in 8 cases and it was less than 400 g in the other 37 cases. In the group of multipara, placenta did not shown morphological alterations in all the cases, but the weight was normal in only 3 cases and it was lower in the remaining 12 cases. The placental microscopic examination pointed out: infarct focus in 34 cases (60%), 12 (35%) of which were recent and 22 (65%) were old infarct focuses; immaturity of chorionic villus in 15 (30%) of the examined placentas; increase in the cytotrophoblast mitotic index in 49 cases (90%) and placenta with normal histological appearance in 11 cases (10%). CONCLUSION: Placental examination, both with macroscopic and microscopic techniques, can lead to the identification of basic morphological alterations which can be easily documented and useful for the diagnosis of feto-neonatal pathologies. A good placental functionality influences both fetal life and postnatal life. Thus, a greater attention to the placental examination in obstetric practice is suggested, especially for maternal and fetal pathologies.  相似文献   
74.
Is uterine artery embolization for cervical ectopic pregnancy always safe?   总被引:2,自引:0,他引:2  
The study objective was to assess the feasibility and the efficacy of bilateral uterine artery embolization (BUAE) for the treatment of cervical pregnancy. The design was a series of 3 cases of viable cervical pregnancy diagnosed by transvaginal ultrasonography and treated by means of BUAE and subsequent uterine curettage. Three women with viable cervical pregnancy underwent BUAE and subsequent uterine curettage in the department of obstetrics and gynecology, High Risk Pregnancy Center, University "Federico II" of Naples. Measurements included surgical outcomes and preservation of fertility. The treatment was effective in all cases. Two patients resumed normal menstruation about 1 month after the procedure, whereas 1 patient underwent a hysterectomy 2 weeks after embolization because of acute ischemic degeneration of a concomitant myoma. The conservative management of cervical pregnancy with angiographic BUAE is a feasible and effective option, even if subsequent hysterectomy may be required. Counseling is necessary.  相似文献   
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Assessing maximum voluntary bite force is important to characterize the functional state of the masticatory system. Due to several factors affecting the estimation of the maximum bite force, a unique solution combining desirable features such as reliability, accuracy, precision, usability, and comfort is not available. The aim of the present study was to develop a low-cost bite force measurement device allowing for subject-specific customization, comfortable bite force expression, and reliable force estimation over time. The device was realized using an inexpensive load cell, two 3D printed ergonomic forks hosting reusable subject-specific silicone molds, a read-out system based on a low-cost microcontroller, and a wireless link to a personal computer. A simple model was used to estimate bite force taking into account individual morphology and device placement in the mouth. Measurement reliability, accuracy, and precision were assessed on a calibration dataset. A validation procedure on healthy participants was performed to assess the repeatability of the measurements over multiple repetitions and sessions. A 2% precision and 2% accuracy were achieved on measurements of forces in the physiological range of adult bite forces. Multiple recordings on healthy participants demonstrated good repeatability (coefficient of variation 11%) with no significant effect of repetition and session. The novel device provides an affordable and reliable solution for assessing maximum bite force that can be easily used to perform clinical evaluations in single sessions or in longitudinal studies.  相似文献   
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The miniaturized metalloenzyme Fe(iii)-mimochrome VI*a (Fe(iii)-MC6*a) acts as an excellent biocatalyst in the H2O2-mediated oxidative dehalogenation of the well-known pesticide and biocide 2,4,6-trichlorophenol (TCP). The artificial enzyme can oxidize TCP with a catalytic efficiency (kcat/KTCPm = 150 000 mM−1 s−1) up to 1500-fold higher than the most active natural metalloenzyme horseradish peroxidase (HRP). UV-visible and EPR spectroscopies were used to provide indications of the catalytic mechanism. One equivalent of H2O2 fully converts Fe(iii)-MC6*a into the oxoferryl-porphyrin radical cation intermediate [(Fe(iv) Created by potrace 1.16, written by Peter Selinger 2001-2019 O)por˙+], similarly to peroxidase compound I (Cpd I). Addition of TCP to Cpd I rapidly leads to the formation of the corresponding quinone, while Cpd I decays back to the ferric resting state in the absence of substrate. EPR data suggest a catalytic mechanism involving two consecutive one-electron reactions. All results highlight the value of the miniaturization strategy for the development of chemically stable, highly efficient artificial metalloenzymes as powerful catalysts for the oxidative degradation of toxic pollutants.

The artificial metalloenzyme FeMC6*a is able to perform the H2O2-mediated dechlorination of 2,4,6-trichlorophenol with unrivalled catalytic efficiency, highlighting its potential application for the removal of toxic pollutants.  相似文献   
80.
Tin-bronze alloys with a tin content of at least 10 wt% have excellent mechanical properties, wear resistance, and corrosion resistance. Among these alloys, Cu-10Sn was investigated in this study for production with the laser powder bed fusion process with a 500W Yb:YAG laser. In particular, a design of experiment (DoE) was developed in order to identify the optimal process parameters to obtain full density, low surface roughness, and high dimensional accuracy. Samples were characterized with Archimedes’ method and optical microscopy to determine their final density. It was shown that the first method is fast but not as reliable as the second one. A first mechanical characterization was performed through microhardness tests. Finally, a set of process parameters was identified to produce fully dense samples with low surface roughness and high accuracy. The results showed that the volumetric energy density could represent an approach that is too simplified, therefore limiting the direct correlation with the physical aspects of the process.  相似文献   
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