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11.

Introduction

Adrenal insufficiency (AI) has a great impact on the prognosis of patients with traumatic brain injury. There is a lack of consensus regarding the diagnostic criteria of AI. In these patients with acute stress we compared fasting cortisol, low and high dose cosyntropin stimulation tests to assess adrenal function in patients with moderate to severe traumatic brain injury.

Material and methods

This multicenter, cross-sectional study recruited 50 consecutive patients (aged between 15 and 70 years old) with moderate to severe traumatic brain injury who survived more than 5 days after the event. The patients’ adrenal function was assessed using the fasting cortisol, 1 and 250-µg ACTH stimulation tests.

Results

More cases of AI were detected by the 1-µg ACTH stimulation test compared to those detected by the basal serum cortisol level and 250-µg ACTH stimulation test. The κ test showed no agreement between these tests. The incidence of AI in the first 10 days after traumatic brain injury varied from 34% to 82% according to the various definitions of AI. The incidence of hypotension and need for vasopressors was higher in the patients diagnosed by the 250-µg ACTH stimulation test (p < 0.0001).

Conclusions

The incidence of secondary AI in moderate to severe traumatic brain injury seems to be high. A combination of stimulation test (either 250 or 1 µg) and basal cortisol level may improve diagnostic ability compared to either test alone. Hence performing both tests for the assessment of adrenal function in patients with traumatic brain injury is recommended.  相似文献   
12.

Background

Based on previous studies, Iran is located in a low risk area in terms of multiple sclerosis (MS). The objective of this study was to determine and compare the incidence, prevalence and demographic characteristics of MS in two ethnic groups of Persian and Arab over the period spanning 2009 in the Khuzestan province, in the Southwest of Iran.

Methods

A cross-sectional case register study was conducted between January and August 2009. All cases in the region whom were referred to the MS society in the city of Ahwaz were participants in the study. The population data from the Iranian Bureau of Statistics were used to calculate the population at risk based on the 1996 and 2006 census data.

Results

A total of 696 patients were identified according to the McDonald criteria during the last 12 years of which 569 patients were Persian. In 2009 the total prevalence and incidence rates of MS were 16.28 and 2.20 per 100,000 individuals. Based on these values, the female to male ratios were 3.11. The Persians manifested more sensory signs and symptoms (40.2%) but motor deficits (19.1%) and cerebellar findings (18.2%) were seen as being more manifest in Arab individuals. The main difference was observed in the progressive types of MS in which 24.7% of the Arab patients showed progressive type symptoms as compared to 15.9% of the cases in the Persian population.

Conclusion

According to this study the authors conclude that the prevalence and incidence of MS were higher in Persians; however progressive forms of MS with motor and cerebellar signs are more frequent in the Arab ethnic group.  相似文献   
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Dendritic cells (DCs) are a subset of antigen-presenting cells (APCs) that are involved in the initiation and control of the immune response to antigens present at the interface with the environment. A limited number of groups have studied DCs in human and animal conjunctiva but no data is available concerning the different DC subsets present in the conjunctival tissue. The aims of this study are to characterize the phenotypes and numbers of DCs present in the murine model of allergic conjunctivitis using the technique of immunohistochemistry so as to aid the understanding of the mechanisms involved in allergic eye disease. A double immunofluorescence method was used to analyze the phenotypic distribution and density of DC subsets in the mouse conjunctival tissues of the allergic model using a panel of antibodies: CD11c, as a general marker of DCs, coupled with another DC subset marker such as Langerin for Langerhans cells (LCs), CD11b for myeloid DCs (mDCs) and mPDCA-1 for plasmacytoid DCs (pDCs). In the na?ve conjunctiva, mDCs were consistently detected in the subepithelial layer and substantia propria. In the epithelium and the subepithelial layer, very few LCs and virtually no pDCs were observed. Following allergen challenge, there was a marked influx of mDCs and pDCs, but no LCs, into the subepithelial layer and throughout the substantia propria. These results indicate that conjunctival DC subsets may play an important role in the immune-regulatory processes involved in the inflammatory component of allergic conjunctivitis.  相似文献   
15.

Purpose

Postdural puncture headache (PDPH) is the most common and still unresolved postoperative complication of spinal anesthesia. Although there are several positive results of intrathecal saline injection for the treatment of PDPH and prophylaxis after accidental dural puncture, the effect of deliberate intrathecal saline injection before spinal anesthesia has not been examined. The objective of our study was to evaluate the effect of prophylactic administration of intrathecal normal saline in decreasing PDPH.

Methods

One hundred healthy women (ASA physical status I) of age between 18 and 35 years scheduled for elective term cesarean delivery under spinal anesthesia were included. Patients were randomly divided into two equal groups. Group C received 2.5 ml (12.5 mg) hyperbaric bupivacaine 0.5 % as a control, and group S received intrathecal normal saline 5 ml before intrathecal injection of 2.5 ml (12.5 mg) hyperbaric bupivacaine 0.5 %. The incidence and severity of PDPH were assessed after 48 h and again 3–7 days after operation.

Results

Basal characteristics were statistically similar in both groups (P > 0.05). The incidences of moderate and severe PDPH during first postoperative 48 h were not different between the groups (P = 0.24). However, the frequency of PDPH after 3–7 days was statistically higher in group C in compared with group S (16 vs. 2 %, P = 0.03). Totally the frequency of PDPH was higher in group C (24 vs. 2 %, P = 0.002).

Conclusion

Administration of normal saline (5 ml) before intrathecal administration of hyperbaric bupivacaine as a preventive approach is an effective and simple way to minimize PDPH in patients undergoing cesarean section.  相似文献   
16.
H-Y antigens are a group of minor histocompatibility antigens encoded on the Y-chromosome with homologous H-X antigens on the X-chromosome. The disparate regions of the H-Y antigens are highly immunogenic and play an important role in understanding human alloimmunity. In this review, we investigate the history of H-Y antigen discovery along with their critical contributions in transplantation and pregnancy. In hematopoietic cell transplantation, male recipients with female donors who become seropositive for B-cell responses as H-Y antibodies following transplantation have increased rates of chronic graft-versus-host disease and decreased rates of relapse. Conversely, female patients who receive male kidney allografts are more likely than other gender combinations to develop H-Y antibodies and reject their allografts. Finally, in the setting of pregnancy, mothers who initially gave birth to boys are more likely to have subsequent pregnancy complications, including miscarriages, in association with H-Y antibody development. H-Y antigens continue to serve as a model for alloimmunity in new clinical scenarios. Our development of more sensitive antibody detection and next-generation DNA sequencing promises to further advance our understanding and better predict the clinical consequences of alloimmunity.  相似文献   
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The objective was to use the United States Renal Data System (USRDS) to quantify the relationship between immunosuppressant therapy (IST) adherence and risk of graft failure among adult renal transplant recipients (RTRs). A secondary objective was to examine the relationship among select patient characteristics and IST adherence. The study sample included adult RTRs who: received primary transplant between January 1, 1999 and December 31, 2005; experienced graft survival for at least 12 months post‐transplant and had at least 12 months of data in the USRDS; utilized Medicare coverage for IST; and were prescribed cyclosporine or tacrolimus. IST adherence was measured by medication possession ratio (MPR). Pearson chi‐square tests were used to examine associations between patient characteristics and MPR quartiles. Cox proportional hazards regression was used to assess relationships among time to graft failure, MPR, and patient characteristics. Thirty‐one thousand nine hundred and thirteen RTRs met inclusion criteria. Older age, female gender, white race, deceased donors, and tacrolimus were associated with greater adherence (p < 0.001). Cox proportional hazard modeling indicated greater adherence, white race, and having a living donor were significantly associated with longer graft survival (p < 0.05). Future prospective studies should further examine the clinical significance of IST nonadherence as it relates to graft failure.  相似文献   
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