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71.
We sought to determine the relationship between the mechanical axis-derived and the anatomic landmark-derived femoral rotational axes using three dimensional computed tomographic images of 20 lower extremities. The mechanical axis-derived femoral rotational axis was created on the distal articular surface of the femur using coronal mechanical limb axis and the reconstructed images of the femur. Then, we measured the angular difference between mechanical axis-derived and anatomic landmark-derived femoral rotational axes. The mechanical axis-derived femoral rotational axis was externally rotated with a mean of 2.2° (range, 0 to 4.7°; SD, 1.0) compared with the surgical epicondylar axis. Our findings should be considered to obtain a proper femoral rotational axis in total knee arthroplasty.  相似文献   
72.

Background

A second-look endoscopy is routinely performed after endoscopic submucosal dissection (ESD) in many institutions, although the need is questionable. Additional hemostatic procedures might be necessary for the post-ESD ulcer with a high risk of bleeding. We investigated the predictive factors for post-ESD ulcers with a high risk of bleeding.

Methods

Second-look endoscopy was performed on the day following ESD. The post-ESD ulcers were categorized into two risk groups according to the Forrest classification: high-risk ulcer stigma (type I and IIa) and low-risk ulcer stigma. We analyzed the risk factors associated with high-risk ulcer stigma and late delayed bleeding.

Results

During the study period, 616 ESD procedures were performed. Second-look endoscopy revealed that the incidence of high-risk ulcer stigma post-ESD was 15.1 %. Early and late delayed bleeding rates were 3.7 and 1.9 %, respectively. Multivariate analysis revealed that submucosal fibrosis and nausea were significantly related to high-risk ulcer stigma after ESD. Multivariate analysis revealed that surface erosion, location of the lesion, and high-risk ulcer stigma identified by second-look endoscopy were significantly associated with late delayed bleeding.

Conclusions

The effective use of selective second-look endoscopy will help limit unnecessary procedures. Submucosal fibrosis and nausea were risk factors associated with high-risk ulcer stigma after ESD.  相似文献   
73.
74.
Shortage of donor cornea is a significant problem in Asia, and xenocorneal transplantation is being actively studied to alleviate this problem. However, the attitudes of subjects who await corneal transplants toward xenocorneal transplantation are not known at all. Thus, this study aimed to investigate the attitudes of subjects on the waiting lists for corneal transplants, toward corneal xenotransplantation. A telephone questionnaire survey comprising six items was conducted in 132 subjects among the wait‐listed individuals (n = 590) who were awaiting corneal transplantation or had undergone corneal transplantation at Seoul National University Hospital from July, 2003 to August, 2012. Among six inquiries, four questions were used to analyze attitudes toward corneal xenotransplantation. Each question pertained to (1) the acceptance of xenocorneal transplantation, (2) willingness to participate in clinical trials, (3) worries in xenocorneal transplantation, and (4) the concern of self‐identity or social life after xenocorneal transplantation. To analyze demographic factors influencing the question, the subjects were arbitrarily divided into two groups: the young (age < 60 yr, n = 58) and the elderly (age ≥ 60 yr, n = 74) or the less‐educated (n = 53) and the well‐educated with high school diploma, college graduation, or higher education (n = 79). Collected demographic data were analyzed as influencing factors on each question using a chi‐square and logistic regression tests. In this study, 42.4% of the subjects (n = 56) expressed favorable views on xenocorneal transplantation using porcine corneas to cure visual loss from corneal blindness. Among those subjects expressing favorable views (n = 56), the willingness to participate in clinical trials, knowing they and their spouses must undergo long‐term surveillance, was 62.5% (n = 35). There were 76.5% of subjects (n = 101) expressing worries regarding xenocorneal transplantation, while 28.8% of subjects (n = 38) expressed their concerns about self‐identity or social life after xenotransplantation. Younger subjects expressed more worry about xenotransplantation than elderly subjects. The well‐educated expressed less concern over self‐identity and social life than the less‐educated. This survey among subjects who are wait‐listed for corneal transplant or who have received a corneal transplant demonstrates that there is an interest in xenocorneal transplantation as an alternate procedure, although there are worries about the procedure that should be further explored in educational campaigns and future studies of the general population.  相似文献   
75.
Mice expressing the minor lymphocyte stimulation antigens, Mls-1a, -2a, or -3a, singly on the B10.BR background have been generated. Mls phenotypes correlate with the integration of mouse mammary tumor viruses (MTV) in the mouse genome. The open reading frames within the 3' long terminal repeats of the integrated MTVs 1, 3, 6, and 13 encode V beta 3-specific superantigens. Sequence data for these viral superantigens is presented, indicating that it is the COOH-terminal portion of the viral superantigen that interacts with the T cell receptor V beta element.  相似文献   
76.
Brain tissue responses to ischemia   总被引:30,自引:0,他引:30       下载免费PDF全文
  相似文献   
77.
Shin JS  Lee SW  Kim NH  Park JS  Kim KJ  Choi SH  Hong YS 《Resuscitation》2007,75(1):184-188
Two patients presented with potentially fatal pulmonary oedema after accidental exposure to nitric and hydrofluoric acid fumes during electroplating. Despite aggressive respiratory support, one succumbed to respiratory failure 3.5h after inhalation. The other patient also rapidly progressed to respiratory failure. Extracorporeal life support (ECLS) was started 5h after exposure at the ED. During ECLS, hypoxia improved, but pulmonary oedema shown by chest radiography became aggravated. N-Acetyl cysteine and calcium gluconate were given i.v. on the first day of admission and nebulised for 48 h after exposure. Pulmonary secretions were significantly reduced 24 h after the nebulising therapy began. Ultimately, the patient was discharged without serious pulmonary or neurological complications after 28 days of hospitalisation. In this case, early ECLS, nebulised antioxidant and antidote were available to treat potentially fatal pulmonary oedema after exposure to nitric and hydrofluoric acid fumes.  相似文献   
78.
BACKGROUND: Pneumoperitoneum after cardiopulmonary resuscitation may be due to mediastinal air tracking into the peritoneal cavity via the diaphragmatic hiatus or to gastric perforation. CASE REPORT: A 79-year-old woman received Advanced Cardiac Life Support measures in the intensive care unit. Chest compressions and endotracheal intubation were performed; a stable cardiac rhythm and perfusion were restored. A chest radiograph after resuscitation revealed pneumoperitoneum without pneumomediastinum. The patient underwent laparotomy; a 6-cm perforation of the posterior gastric wall along the lesser curve was detected and repaired. CONCLUSION: Gastric perforation after cardiopulmonary resuscitation should be suspected when chest radiographs obtained after resuscitation show pneumo-peritoneum without pneumomediastinum. Prompt laparotomy allows detection of gastric perforations and decreases the morbidity associated with rupture of a hollow organ. The incidence of gastric perforation after cardiopulmonary resuscitation may be decreased with early endotracheal intubation, avoidance of esophageal intubation, and expeditious placement of an orogastric tube.  相似文献   
79.
80.

Background

Gas exchange disturbance may develop during urologic robotic laparoscopic surgery with the patient in a steep Trendelenburg position. This study investigated whether prolonged inspiratory time could mitigate gas exchange disturbances including hypercapnia.

Methods

In this randomized cross-over trial, 32 patients scheduled for robot-assisted urologic surgery were randomized to receive an inspiratory to expiratory time ratio (I:E) of 1:1 for the first hour of pneumoperitoneum followed by 1:2 for last period of surgery (group A, n?=?17) or I:E of 1:2 followed by 1:1 (group B, n?=?15). Arterial blood gas analysis, airway pressure and hemodynamic variables were assessed at four time points (T1: 10?min after induction of general anesthesia, T2: 1?h after the initiation of pneumoperitoneum, T3: 1?h after T2 and T4: at skin closure). The carry over effect of initial I:E was also evaluated over the next hour through arterial blood gas analysis.

Results

There was a significant decrease in partial pressure of oxygen in arterial blood (PaO2) for both groups at T2 and T3 compared to T1 but in group B the PaO2 at T4 was not decreased from the baseline. Partial pressure of carbon dioxide in arterial blood (PaCO2) increased with I:E of 1:2 but did not significantly increase with I:E of 1:1; however, there were no differences in PaO2 and PaCO2 between the groups.

Conclusion

Decreased oxygenation by pneumoperitoneum was improved and PaCO2 did not increase after 1 h of I:E of 1:1; however, the effect of equal ratio ventilation longer than 1 h remains to be determined. There was no carryover effect of the two different I:E ratios.
  相似文献   
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