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41.
42.
Human intravenous immunoglobulin (IVIG) preparation containing a variety of antibodies is widely used against severe infectious diseases. Although IVIG is supposed to promote phagocytosis of opsonized bacteria and neutralize several bacterial toxins, it is unclear what antibodies are responsible for the effect in clinical use. In this study, we found that IVIG showed neutralizing activity against toxic shock syndrome toxin-1 (TSST-1), produced by methicillin-resistant Staphylococcus aureus (MRSA). Whereas intravenous inoculation with culture medium of MRSA 1945 strain into ICR mice causes immediate death, all of the mice survived in case of previous administration of IVIG. Such effect might be attributed to neutralization of TSST-1. Murine splenocytes incubated with TSST-1 (1.0 ng/mL) for 48 hours produced IFN-gamma. By addition of IVIG at 100 micrograms/mL into culture medium, production of IFN-gamma was completely inhibited. From IVIG, anti-TSST-1 antibody was purified by affinity chromatography as one of the effective antibodies. MRSA 1945 mixed with dextran-based microcarrier beads and injected subcutaneously into mice resulted in the formation of abscess and excretion of TSST-1 in serum for 14 days. IVIG and anti-TSST-1 antibody neutralized TSST-1 in blood 24 hours after infection, although bacterial count was kept constant. Experimental rabbit TSS model was established by synergism with lipopolysaccharide (LPS) of Escherichia coli. Anti-TSST-1 antibody protected NZW rabbits from lethal challenge with TSST-1 (1 microgram/kg, i.v.) 4 hours before LPS in a dose-dependent manner (10 micrograms/kg, i.v.), whereas all of the NZW rabbits died in the control group. Thus, IVIG may be a useful tool in the prevention and perhaps therapy of staphylococcal infections and TSS.  相似文献   
43.
We examined the response of ventriculo-arterial coupling to epinephrine in 19 patients with normal left ventricular function and with left ventricular dysfunction of various degrees using a conductance catheter. They were divided into three groups: group I, seven patients without left ventricular wall motion abnormality; group II, six patients with ejection fraction of 45-60%; group III, six patients with ejection fraction of 28-40%. Changes in the slope of the end-systolic pressure-volume relationship (end-systolic elastance), the effective arterial elastance, the ratio of effective arterial elastance to end-systolic elastance and the ventricular work efficiency during administration of two different doses of epinephrine (0.05 and 0.1 micrograms/kg/min) were compared among the three groups. At baseline there were no significant differences among the three groups in the ratio of effective arterial elastance to end-systolic elastance, or ventricular work efficiency. At the lower dose of epinephrine, the mean ratio of effective arterial elastance to end-systolic elastance decreased and the mean ventricular work efficiency increased in any groups. At the higher dose of epinephrine the mean ratio of effective arterial elastance to end-systolic elastance further decreased and the mean ventricular work efficiency further increased in groups I and II. However, the mean ratio of effective arterial elastance to end-systolic elastance did not decrease but the mean ventricular work efficiency even decreased in group III. Thus, in patients with advanced left ventricular dysfunction, even a high dose of epinephrine does not modulate the ventriculo-arterial coupling to increase ventricular work efficiency.  相似文献   
44.

Background

Influenza A(H1N1)pdm09 virus infections often manifest severe respiratory symptoms, particularly in patients with a past history of allergic disease. Most of these findings were reported during the 2009 pandemic. The purpose of this study was to detail the clinical characteristics of influenza virus-induced lower respiratory infection (LRI) during the A(H1N1)pdm09-predominant 2015–2016 season.

Methods

We retrospectively reviewed the clinical characteristics of influenza-induced LRI cases in children admitted to a tertiary children's hospital. Molecular diagnostic evaluation was performed on samples obtained from the most severe cases.

Results

We identified 66 patients with influenza-associated hospitalization and included 21 patients with influenza virus-induced LRI for analyses. Twelve patients (57%) were admitted to the pediatric intensive care unit, seven (33%) required mechanical ventilation, and three (14%) required extracorporeal membrane oxygenation. Plastic bronchitis (PB) was identified in six patients (29%), among whom a past medical history of asthma or food allergy were noted in all six patients. A past history of allergic disease was more common among patients with, than among those without, PB (p = 0.009). A(H1N1)pdm09 was detected from all the PB cases, and phylogenetic analyses of the hemagglutinin and neuraminidase genes demonstrated that this virus belonged to subclades 6B.1 and 6B.2. In the six PB cases, we found one patient with H275Y mutation in neuraminidase.

Conclusion

Allergic disease was a risk factor for developing PB due to influenza A(H1N1)pdm09 infection during the 2015–16 season.  相似文献   
45.
Molecular hydrogen (H2) is clinically administered; however, in some hospitals, H2 is given to patients without consideration of its safe use. In the present study, we prepared convenient and safe devices for the drinking of super-saturated H2 water, for intravenous drip infusion of H2-rich saline, and for the inhalation of H2 gas. In order to provide useful information for researchers using these devices, the changes in H2 concentration were studied. Our experimental results should contribute to the advance of non-clinical and clinical research in H2 medicine.  相似文献   
46.
An extremely rare case of splenic rupture at the site of metastasis of hepatocellular carcinoma is reported. A 62-yr-old woman with hepatocellular carcinoma and its suspected metastasis to the spleen died of intraperitoneal hemorrhage. Autopsy disclosed a laceration of the spleen as the definitive cause of the hemorrhage. There were multiple nodules of metastatic hepatocellular carcinoma in the spleen, some of which were exposed at the lacerated portion of the splenic capsule. This may be the first report of a case of spontaneous rupture of the spleen secondary to metastatic hepatocellular carcinoma. Splenic rupture can he one of the causes of hemoperitoneum in patients with hepatocellular carcinoma.  相似文献   
47.
The validity of coronary angioscope was discussed in several clinical settings in this article. First of all, although smooth coronary surface was observed by coronary angiography after the intervention of chronic total occlusion, protrusion or thrombus observed by angioscope occupied the arterial lumen and closed the vessel lumen. After implantation of the stent, lumen was widely opened. Serial angioscopic observation revealed that the neointima became thick and non-transparent until 6 months and then became thin and transparent by 3 years after stent implantation. These findings suggested the validity of angioscope in coronary intervention. Second, coronary angioscope revealed the morphologic and pathologic characteristics of culprit lesions in patients with acute coronary syndrome. The thrombus was observed on the yellow plaque in the culprit lesion. The thrombus formed directly over the plaque was mainly white and red thrombus might be formed after the blood flow was disturbed by the white thrombus formed by the platelet aggregation. These findings imply the importance of anti-platelet therapy after acute coronary syndromes. Finally, the angioscope can detect the minimal changes of the plaque formation, progression and rupture, that is, the entire process of the atherosclerosis. The early detection of yellow plaque might be able to intervent mechanically or pharmacologically to prevent its rupture.  相似文献   
48.
PURPOSE: This investigation aimed to examine the physical activity patterns of cardiac rehabilitation program (CRP) participants. METHODS: The investigation enrolled 53 male and 24 female CRP participants between 46 and 88 years of age. By means of a uniaxial accelerometer (Life-Corder), the amount of physical activity (in kilocalories) and the time spent in physical activity at light (<3 metabolic equivalents [METs]), moderate (3 to 6 METs), and vigorous (>6 METs) intensity were evaluated. In addition to these variables, the MET levels for the CRP and non-CRP periods were calculated. RESULTS: The weekly amount of physical activity energy expenditure averaged 1597 +/- 846 kcal/week, and the time spent in light, moderate, and vigorous physical activity averaged, respectively, 375.5 +/- 124.5 minutes, 125.2 +/- 109.4 minutes, and 5.7 +/- 12.8 minutes per week. These levels were significantly lower on non-CRP days than on CRP days: 177 +/- 113 versus 299 +/- 161 kcal/day and, respectively, 49.3 +/- 19.3 versus 59.7 +/- 19.8 minutes, 10.5 +/- 14.6 versus 26.4 +/- 20.4 minutes, and 0.4 +/- 1.7 versus 1.4 +/- 3.0 minutes per day. CONCLUSIONS: These results indicate that the amount of physical activity was generally adequate on CRP days, but failed to reach target levels on non-CRP days. Thus CRP participants, when it is medically appropriate, should be encouraged to incorporate lifestyle physical activity, additional exercise, or both on non-CRP days to supplement their caloric expenditure from CRP exercise sessions.  相似文献   
49.
50.
Anomalous coronary arteries are usually identified incidentally by angiography or autopsy, but some "malignant" coronary anomalies are associated with a high incidence of syncope, arrhythmia, myocardial infarction, and sudden death. So far, the pathogenesis of the coronary events in such cases has only been revealed by autopsy. In the present case report, a patient with anomalous origin of the right coronary artery from the left sinus of Valsalva developed acute myocardial infarction, and visualization of the anomaly and assessment of the culprit plaque in the artery were done by multidetector row computed tomography and intravascular ultrasound.  相似文献   
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