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41.
Salmonella species include facultative intracellular pathogens which reside preferentially within cells of the host's reticulo-endothelial system. Resistance to Salmonella involves a collaboration between cells of the innate and adaptive immune systems, and protective immunity requires cell-mediated and humoral-immune responses. CD40-CD154 interactions are of central importance in the induction of cellular immune responses. In the present study, CD154-deficient (CD154(-/-)) mice were used to assess the role of CD40-CD154 interactions in immunity to Salmonella infection. Compared to C57BL/6 (CD154(+/+)) controls, CD154(-/-) mice were hypersusceptible to infection by an attenuated strain of Salmonella enterica serovar Typhimurium (S. typhimurium), as evidenced by a significantly decreased survival rate. CD154(-/-) mice exhibited a defect in the production of IFN-gamma and NO in the acute phase of the disease, which resulted in a failure to control bacterial replication. We conclude that intercellular communications via the CD40-CD154 pathway play a critical role in the induction type-1 cytokine responses and protection against primary infections with attenuated Salmonella.  相似文献   
42.
Sex differences in brain activation elicited by humor   总被引:8,自引:0,他引:8       下载免费PDF全文
With recent investigation beginning to reveal the cortical and subcortical neuroanatomical correlates of humor appreciation, the present event-related functional MRI (fMRI) study was designed to elucidate sex-specific recruitment of these humor related networks. Twenty healthy subjects (10 females) underwent fMRI scanning while subjectively rating 70 verbal and nonverbal achromatic cartoons as funny or unfunny. Data were analyzed by comparing blood oxygenation-level-dependent signal activation during funny and unfunny stimuli. Males and females share an extensive humor-response strategy as indicated by recruitment of similar brain regions: both activate the temporal-occipital junction and temporal pole, structures implicated in semantic knowledge and juxtaposition, and the inferior frontal gyrus, likely to be involved in language processing. Females, however, activate the left prefrontal cortex more than males, suggesting a greater degree of executive processing and language-based decoding. Females also exhibit greater activation of mesolimbic regions, including the nucleus accumbens, implying greater reward network response and possibly less reward expectation. These results indicate sex-specific differences in neural response to humor with implications for sex-based disparities in the integration of cognition and emotion.  相似文献   
43.
BACKGROUND AND PURPOSE: Percutaneous vertebroplasty has been performed in the United States in an increasing volume since the mid-1990s. The purpose of this study is to analyze the risk of a new symptomatic vertebral compression fractures within 1 year of having an acute/subacute fracture treated with vertebroplasty. METHODS: A retrospective analysis was performed in which 253 female patients were found to have acute/subacute vertebral compression fractures secondary to osteoporosis treated with percutaneous vertebroplasty. Occurrences of new symptomatic vertebral compression fractures were recorded for a year following initial vertebroplasty. RESULTS: Fifty-five patients (21.7%) of the 253 osteoporotic women with one or more initial fractures experienced a new symptomatic vertebral compression fracture within 1 year. CONCLUSION: Roughly one-fifth of osteoporotic women with acute/subacute fracture treated with vertebroplasty will have a subsequent fracture within 1 year.  相似文献   
44.
BACKGROUND AND PURPOSE: Adjacent fracture formation after percutaneous vertebroplasty has been reported in literature. The purpose of this study was to determine whether intervertebral disk extravasation is related to adjacent fracture formation in low-volume cement-filling vertebroplasty. METHODS: A retrospective analysis of 308 patients having vertebroplasty was undertaken. Anteroposterior and lateral procedural fluoroscopy radiographs were analyzed for mild, moderate, or severe disk extravasation. Symptomatic refracture location relative to the presence or absence of extravasation was analyzed on follow-up fluoroscopy radiographs. RESULTS: Of the 308 patients in the study, 81 patients had disk extravasation at a total of 85 vertebral levels; 40 levels had mild extravasation, 38 levels had moderate extravasation, and 7 had severe extravasation. Of the 40 levels with mild extravasation, 6 new adjacent fractures occurred next to the disk leakage. Of the 38 with moderate extravasation, 6 new adjacent fractures occurred. Of the 7 levels of severe extravasation, only one new adjacent fracture occurred. Hence, a total of 13 adjacent fractures occurred next to disk extravasation; 13 nonadjacent fractures also occurred in the patients with disk extravasation. In the patients without disk extravasation, 28 adjacent and 24 nonadjacent subsequent fractures occurred. The average available cement volumes injected into vertebral bodies causing disk leakage ranged from 4.78 to 5.60 mL. CONCLUSIONS: With low-volume cement-filling percutaneous vertebroplasty, we cannot conclude (level of significance alpha = .05) that for patients who have a new fracture there is significance between the location of the fracture and the occurrence of disk extravasation.  相似文献   
45.
Craniofacial distraction osteogenesis (DO) was found to be a procedure with low preoperative and postoperative morbidity. Direct current electrical stimulation is used clinically to treat different orthopaedic problems. It provided a significant increase in new-bone formation, and a higher mechanical strength of healing.The purpose of this study was to test the effect of electric current on distraction osteogenesis and to establish the best period to apply an electric current during the different distraction phases.Twelve healthy adult goats were subjected to a vertical osteotomy in the symphyseal area. A distraction device was fixed to the bone. Animals were divided into two groups, Group I (three goats) and group II (nine goats). In group I, the device was activated 1mm per day for 10 days; while in group II, the device was activated 1mm per day for 10 days with the application of direct electric current stimulation of 10 microA either during the first 3 days of latency in a continuous mode (ESL group), or during the first 3 days of the activation period in a continuous mode (ESA group); or during the first 3 days of the consolidation period in a continuous mode (ESC group). After the activation period was completed, the distraction device left in place for additional 15 days for bone consolidation in all animals. Animals were then sacrificed, the mandible was harvested, and the distracted areas were removed and processed for mechanical and histological studies. The results of this study suggested that direct current electrical stimulation display synergism on mandibular distraction when this stimulation applied to the distraction zone during activation or consolidation periods.  相似文献   
46.
OBJECTIVES: To determine the effectiveness and safety of misoprostol in severe pre-eclampsia and eclampsia patients with unripe cervix. METHODS: A prospective observational study was carried out in 135 severe pre-eclampsia and eclampsia patients who required termination of pregnancy at the Department of Obstetrics and Gynecology, Khulna Medical College Hospital, Khulna, Bangladesh during January 2002 to October 2003. Fifty micrograms of misoprostol was used every 4 h in cases of unripe cervix (Bishop score < or = 6) in severe pre-eclampsia and eclampsia patients. Maternal and perinatal outcome as well as any complications were recorded. RESULTS: In severe pre-eclampsia and eclampsia patients vaginal delivery occurred in 79.3 and 80.5% of cases, and cesarean section was performed in 20.6 and 19.4% of cases, respectively. The maximum required responsive dose was 50-150 microg. Oxytocin augmentation was required in 29.3 and 35% of cases, respectively. Induction to delivery time was median 8 h, interquartile ranges 4.2-8.2 h in the severe pre-eclampsia group, and median 9 h, interquartile ranges 6.8-12.5 h in the eclampsia group, and average hospital stay was 3.4 +/- 1.8 and 3.7 +/- 1.7 days, respectively. The only maternal complications were hyperstimulation which occurred in 6.8 and 5.1% of cases, respectively. Neonatal death occurred in five (11.3%) and eight cases (12.1%), respectively. CONCLUSION: Intravaginal misoprostol is well tolerated and very effective for the induction of labor in severe pre-eclampsia and eclampsia patients with unripe cervix.  相似文献   
47.
Azim N  Wang CY 《Anaesthesia》2004,59(6):610-612
A 62-year-old male underwent off-pump coronary artery grafting surgery while cerebral function was monitored with bispectral index (BIS). The BIS monitoring was continued into the immediate postoperative period, during which time the patient experienced a cardiopulmonary arrest. The changes in the BIS values helped the resuscitating team in assessing the cerebral response to the cardiopulmonary resuscitation.  相似文献   
48.

Purpose

Setting treatment goals in the intensive care unit (ICU) often involves resuscitation decisions. Our objective was to study the rate of establishing do-not-resuscitate (DNR) directives, determinants, and outcomes of those directives for mechanically ventilated patients.

Methods

In a multicentre observational study, we included consecutive adults with no DNR directives within 24 hr of ICU admission who were mechanically ventilated for at least 48 hr. We identified the rate with which DNR directives were established, and factors associated with these directives.

Results

Among 765 patients, DNR directives were established for 231 (30.2%) patients; 143 (62.1%) of these were established within the first week. Factors independently associated with a DNR directive were: patient age [> 75 yr (hazard ratio [HR] 2.3, 95% confidence interval 1.5–3.4], 65 to 74yr(HR 1.8, 1.2–2.7), 50 to 64 yr (HR 1.4, 1.0–2.2) relative to < 50 yr); medical rather than surgical diagnosis (HR 1.8, 1.3–2.5); multiple organ dysfunction score (HR 1.7 for each five-point increment, 1.4–2.0); physician prediction of ICU survival [< 10% (HR 15.0, 6.7–33.6)], 10 to 40% [(HR 5.0, 2.3–11.2), 41 to 60% (HR 4.0, 1.8–9.0) relative to > 90%]; and physician perception of patient preference to limit life support (no advanced life support [(HR 5.8, 3.6–9.4) or partial advanced life support (HR 3.2, 2.2–4.6) compared to full measures].

Conclusion

One third of mechanically ventilated patients had DNR directives established early during their ICU stay after the first 24 hr of admission. The strongest predictors of DNR directives were physician prediction of low probability of survival, physician perception of patient preference to limit life support, organ dysfunction, medical diagnosis and age.  相似文献   
49.
Bowel perforation is a well-recognized complication of peritoneal dialysis catheter insertion and is associated with increased morbidity and cost of medical care. In this article we describe our 2-year experience (August 2001-October 2003) with a modified peritoneoscopic technique of peritoneal dialysis catheter insertion to minimize the incidence of bowel perforation. Seventy patients underwent 82 consecutive peritoneal dialysis catheter insertions using the innovative technique. The modified technique is very similar to the traditional peritoneoscopic procedure except for the following differences. To gain access to the peritoneal cavity, a Veress insufflation needle (Ethicon Endo-Surgery Inc., Cincinnati, OH) is utilized instead of the trocar. In contrast to the sharp tip of the trocar, the Veress needle has a blunt, self-retracting end. In addition, the Veress needle is only 14 gauge as opposed to the 2.2 mm diameter of the trocar. Upon introduction of the Veress needle into the abdominal cavity, two "pops" are discerned similar to the trocar. After introduction, 400-500 cc of air are infused and the needle is removed. The infusion of air creates a space between the peritoneal surface of the anterior abdominal wall and the bowel loops. At this point, the cannula with trocar is inserted into the space created. The rest of the steps of the procedure are the same as the traditional peritoneoscopic technique. Utilizing the innovative technique, all 82 catheter insertions were performed successfully without a single bowel perforation. No other complications except for catheter migration (n = 2) were noted. The extra cost of the needle (35 USD) should be viewed in the context of the costs associated with management of a bowel perforation. Large-scale studies are needed to confirm the superiority of this innovative technique over the traditional peritoneoscopic insertion found in our case series. In the interim, however, the increased morbidity and cost associated with bowel perforation calls for logical measures to be taken to avoid this dreaded complication.  相似文献   
50.
We report a case of dense and visually significant corneal haze after laser-assisted subepithelial keratectomy (LASEK). Visually significant corneal haze after LASEK can be successfully treated with manual debridement and intraoperative mitomycin-C.  相似文献   
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