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BACKGROUND: Great saphenous vein is one of the most used grafts in cardiovascular surgery. There is little amount of data in the medical literature describing dimensions of this vein. This series describes dimensions of the great saphenous vein in a coronary population and their variations. PATIENTS AND METHODS: Retrospective series of patients admitted to the cardiovascular surgery department of Hotel-Dieu de France Hospital - Beirut, between January 2003 and June 2006 for elective coronary artery bypass grafting and having a preoperative Doppler ultrasound of the saphenous veins according to a standardized protocol. Great saphenous vein dimensions were analyzed with regard to patients' characteristics using multivariable analysis of variance. RESULTS: Four hundred and two subjects were included with a mean age 64.4+/-9.3 years and a mean body mass index 27.9+/-4.5 kg/m(2). Women presented 22.6% of the series. Great saphenous vein dimensions' variations according to gender were significant (Multivariate Pillay trace=0.001) below the knee. Dimensions' variations were also significant as function of body mass index (P=0.001) and body surface (P=0.001). Age and cardiovascular risk factors did not influence GSV diameters. CONCLUSION: This series allowed constructing reference tables of the great saphenous vein segmental diameters in patients admitted for coronary artery surgery. Female sex is associated with lower segmental diameters below the knee and body mass index and body surface are linearly associated with segmental diameters at all levels.  相似文献   
583.
Roche Molecular Systems recently released two PCR-based assays, AMPLICOR and LINEAR ARRAY (LA), for the detection and genotyping, respectively, of human papillomaviruses (HPVs). The manual specimen processing method recommended for use with both assays, AmpliLute, can be time-consuming and labor-intensive and is open to potential specimen cross-contamination. We evaluated the Roche MagNA Pure LC (MP) as an alternative for specimen processing prior to use with either assay. DNA was extracted from cervical brushings, collected in PreservCyt media, by AmpliLute and MP using DNA-I and Total Nucleic Acid (TNA) kits, from 150 patients with histologically confirmed cervical abnormalities. DNA was amplified and detected by AMPLICOR and the LA HPV test. Concordances of 96.5% (139 of 144) (kappa=0.93) and 95.1% (135 of 142) (kappa=0.90) were generated by AMPLICOR when we compared DNA extracts from AmpliLute to MP DNA-I and TNA, respectively. The HPV genotype profiles were identical in 78.7 and 74.7% of samples between AmpliLute and DNA-I or TNA, respectively. To improve LA concordance, all 150 specimens were extracted by MP DNA-I protocol after the centrifugation of 1-ml PreservCyt samples. This modified approach improved HPV genotype concordance levels between AmpliLute and MP DNA-I to 88.0% (P=0.043) without affecting AMPLICOR sensitivity. Laboratories that have an automated MP extraction system would find this procedure more feasible and easier to handle than the recommended manual extraction method and could substitute such extractions for AMPLICOR and LA HPV tests once internally validated.  相似文献   
584.
The association between diet and prostate cancer (PC) risk, although suggestive, still remains largely elusive particularly in the Asian population. This study sought to further evaluate the possible effects of different dietary factors on risk of PC in Iran. Using data from a prospective hospital-based multicenter case-control study, dietary intakes of red meat, fat, garlic, and tomato/tomato products, as well as thorough demographic and medical characteristics, were determined in 194 cases with the newly diagnosed, clinicopathologically confirmed PC and 317 controls, without any malignant disease, admitted to the same network of hospitals. Odds ratios (ORs) and corresponding 95% confidence intervals (CIs) were obtained after adjustment for major potential confounders, including age, body mass index, smoking, alcohol, education, occupation, family history of PC, and total dietary calories. Comparing the highest with the lowest tertile, a significant trend of increasing risk with more frequent consumption was found for dietary fat (OR: 1.79, 95% CI: 1.71-4.51), whereas inverse association was observed for tomato/tomato products (OR: 0.33, 95% CI: 0.16-0.65). A nonsignificant increase in PC risk was revealed for dietary red meat (OR: 1.69, 95% CI: 0.93-3.06). For garlic consumption, a borderline reduction in risk was observed (OR: 0.58, 95% CI: 0.32-1.01; P = 0.05). In conclusion, our study supports the hypothesis that total fat may increase PC risk and tomatoes/tomato products and garlic may protect patients against PC.  相似文献   
585.
One of the challenges on immunodiagnostic of Chagas disease in endemic areas has been the search for more practical and safe antigenic preparation that provides tests with higher sensitivity and specificity, with low cross-reactivity. A new approach using fixed Trypanosoma cruzi epimastigotes to detect IgG reactivity was investigated previously. In order to continue this investigation, this study aimed at optimizing the flow cytometry-based method to the diagnosis of Chagas disease patients after specific chemotherapy. To achieve our goal, serum samples from 93 subjects - 52 adults chronically infected by T. cruzi, and 41 uninfected controls were tested by flow cytometry. Secondly, serum samples from patients Treated Cured and Treated Uncured from Chagas disease were also tested to evaluate the potential of the method on assessing cure. After establishing the ideal serum dilution and cut off, 121 serum samples from patients with other endemic infections were tested to check cross-reactivity. The results showed that parasite staining with Evan's blue dye eliminated debris, allowing trustworthy analysis of anti-fixed epimastigote IgG reactivity. The applicability of the method to diagnose Chagas disease was confirmed by the high sensitivity (98.1%) and specificity (100%) found. This method also contributed for post-therapeutic assessment of cure, identifying 94.1% of Treated Uncured and 83.3% of Treated Cured patients. Cross-reactivity was observed in a very low number (6.7%). On the whole, these data highly recommend the use of anti-fixed T. cruzi epimastigote IgG reactivity by flow cytometry to the diagnosis and cure monitoring of Chagas disease in endemic areas.  相似文献   
586.

Background

Olfactory discrimination depends on the large numbers of odorant receptor genes and differential ligand-receptor signaling among neurons expressing different receptors. In this study, we describe an in vitro system that enables the expression of exogenous odorant receptors in cultured olfactory sensory neurons. Olfactory sensory neurons in the culture express characteristic signaling molecules and, therefore, provide a system to study receptor function within its intrinsic cellular environment.

Results

We demonstrate that cultured olfactory sensory neurons express endogenous odorant receptors. Lentiviral vector-mediated gene transfer enables successful ectopic expression of odorant receptors. We show that the ectopically expressed mouse I7 is functional in the cultured olfactory sensory neurons. When two different odorant receptors are ectopically expressed simultaneously, both receptor proteins co-localized in the same olfactory sensory neurons up to 10 days in vitro.

Conclusion

This culture technique provided an efficient method to culture olfactory sensory neurons whose morphology, molecular characteristics and maturation progression resembled those observed in vivo. Using this system, regulation of odorant receptor expression and its ligand specificity can be studied in its intrinsic cellular environment.  相似文献   
587.
Mandibular advancement (MA) by means of functional orthopedic techniques is currently used in young patients to stimulate mandibular growth. The aim of this study was to evaluate the morphological changes in the mandibles of 2-, 7-, and 16-month-old female mice after MA. Every 3 days during 1 month, the lower incisors were trimmed by 1mm to induce protrusion when the animal was feeding. The left mandibles of the 30 experimental and 28 control individuals were subsequently dissected and digital images were obtained to analyze nine linear/angular measurements. The condylar microstructure was also analyzed by scanning electron microscopy (SEM). The linear/angular measurements showed a growth response in different mandibular regions in 2- and 16-month-old individuals. SEM showed that, in the 7-month-old mice, the condylar cartilage had regenerated in the treated individuals but not in the controls. The results suggest that MA produces mandibular growth in 2- and 16-month-old female mice. Although there was no mandibular growth in 7-month-old mice, regeneration of the condylar cartilage was detected, thus demonstrating that different responses to the MA stimulus occur in female mice of different ages.  相似文献   
588.
Background: Baroreceptor sensitivity (BRS) refers to the magnitude of change in the heart rate in response to change in blood pressure (e.g. upon standing). The impact of regular antenatal exercise on maternal BRS is unclear.

Aims: To determine whether supervised weekly exercise influences BRS, and to determine if posture and calculation method are important in antenatal BRS measurement.

Study design and subjects: Eighty-one healthy pregnant women were randomly assigned to an exercise or control group. The exercise group attended weekly classes from the 20th week of pregnancy onwards.

Outcome measures: Cardiovascular assessments (beat-to-beat blood pressure, heart rate) were performed at 12–16, 26–28, 34–36 weeks and 12 weeks following birth. BRS was calculated using two methods (“sequence” and “beat-to-beat”).

Results: Fifty-one women (63%) completed the study. Mean BRS reduced progressively in all women (p?p?p?p?Conclusions: Weekly exercise exaggerated the reductions in BRS and HRV during pregnancy and is likely linked to diminished parasympathetic activity.  相似文献   
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