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31.
Sera from leprosy patients and controls were assayed for immunoglobulin M (IgM) and IgG antibodies to the Mycobacterium leprae-specific phenolic glycolipid I antigen (PG) by enzyme-linked immunosorbent assay, for IgG antibodies to M. leprae protein antigens by Western immunoblot, and for antibodies to a 65-kilodalton (kDa) protein antigen of M. leprae by a competition antibody binding assay. Elevated levels of anti-PG IgM were seen in lepromatous and borderline lepromatous patients, and elevated levels of anti-PG IgG were seen in borderline lepromatous patients. There was a significant correlation between the bacillary index (BI) and anti-PG IgM whether all leprosy patients or only multibacillary patients were analyzed. A significant correlation was seen between anti-PG IgG and BI when all leprosy patients were used for analysis, but not when only multibacillary patients were used. IgG antibodies to protein antigens of M. leprae, as detected by Western immunoblot, were more prevalent in lepromatous and borderline lepromatous patients than in borderline tuberculoid patients, while one of eight controls showed one weak band. There were significant correlations between the number of M. leprae protein antigens detected by the sera of patients and both BI and the level of anti-PG IgM. The 65-kDa competition antibody binding assay detected active multibacillary leprosy. Patients positive for antibody to the 65-kDa antigen had a significantly higher BI and levels of anti-PG IgM and anti-PG IgG than did patients that were negative. In addition, the level of antibody to the 65-kDa antigen correlated with both the BI and anti-PG IgM. We conclude that testing for antibodies to protein antigens of M. leprae may provide a useful adjunct to testing for antibodies to PG.  相似文献   
32.
Sequential serum samples from leprosy patients at various stages of antibacterial treatment were tested by an ELISA for antibodies to phenolic glycolipid I (PGL-I), a synthetic PGL-I analog (ND-BSA), and lipoarabinomannan (LAM) from Mycobacterium tuberculosis to determine if these antibodies could be useful in monitoring response to therapy. Among patients with positive initial anti-PGL-I IgM, a significant decrease in this antibody was seen over time (p less than 0.01), whether assayed by PGL-I or ND-BSA. The two antigens showed good agreement in the detection of decrease in anti-PGL-I IgM. The greatest decrease was seen in patients with a high initial anti-PGL-I IgM and a high bacterial index (BI). Patients with a declining BI were seen to have generally declining antibody levels to PGL-I and to LAM; in those patients with a fluctuating BI, antibody levels were less predictable. We conclude that antibodies to PGL-I and LAM can be useful in following response to therapy in leprosy patients and that either the native PGL-I or ND-BSA can serve as antigen for the ELISA.  相似文献   
33.
Image-directed percutaneous biopsies with a biopsy gun   总被引:3,自引:0,他引:3  
Core tissue for histologic study is believed by many pathologists to be more diagnostic than material from needle aspiration. Recently, a biopsy "gun" has been introduced, which simplifies core biopsies. With this device, 182 biopsies of multiple anatomic sites were performed with ultrasonic, computed tomographic, and fluoroscopic guidance and 18-gauge needles. High-quality histopathologic specimens were obtained in 177 of the biopsies, and diagnostic target tissue was obtained in 167. Only three significant complications occurred: one bleeding complication that required transfusion and two cases of pneumothorax that necessitated placement of chest tubes. The biopsy gun eliminated the disjointed movements of conventional "skinny" needle biopsies, and none of the samples demonstrated significant "crush" artifact or obscuring blood, problems that are commonly associated with manual biopsy techniques. Patient discomfort was decreased with this system compared with that of manual biopsies, and the total procedure time was reduced. Because of these distinct advantages, the authors now use the biopsy gun exclusively for all percutaneous biopsies and recommend that other institutions consider the use of this biopsy method.  相似文献   
34.

Background

Simulation-based training (SBT) for pediatric trauma resuscitation can improve team performance. The purpose of this study was to describe the nationwide trend in SBT use and barriers to SBT implementation.

Methods

Trauma centers that participated in ACS TQIP Pediatric in 2016 (N?=?125) were surveyed about SBT use. Center characteristics and reported implementation barriers were compared between centers using and not using SBT.

Results

Survey response rate was 75% (94/125) with 78% (73/94) reporting SBT use. The frequency of pediatric SBT use increased from 2014 to 2016 (median 5.5 vs 6.5 annual sessions, p?<?0.01). Funding barriers were negatively associated with number of annual SBT sessions (r?≤??0.34, p?<?0.05). Centers not using SBT reported lack of technical expertise (p?=?0.01) and lack of data supporting SBT (p?=?0.03) as significant barriers.

Conclusions

Simulation use increased from 2014 to 2016, but significant barriers to implementation exist. Strategies to share resources and decrease costs may improve usage.

Level of evidence

Level 3, epidemiological.  相似文献   
35.
Telomeres are terminal, repeated deoxyribonucleic acid (DNA) sequences that stabilize and protect the ends of the chromosomes. Mounting evidence indicates that by initiating chromosomal instability, short dysfunctional telomeres may be involved in prostate carcinogenesis. Although the exact cause of the telomere shortening observed in prostate cancer remains a mystery, telomere loss is known to occur during cell division and oxidative DNA damage, 2 byproducts of chronic inflammation, which is a common histologic finding in the prostate. In addition to prostate cancer causation, telomeres may also play a role in disease progression, and there are indications that tumor telomere content may prove useful as a prognostic marker. Once established, prostate cancer cells almost invariably activate the telomeric DNA polymerase enzyme telomerase, the detection of which may prove useful for diagnostic purposes. Interestingly, telomerase activity is suppressed in prostate cancer cells after androgen withdrawal, raising the possibility that androgen ablative therapies may re-instigate telomere loss, and consequent genetic instability, in surviving cancer cells, thus contributing to the emergence of an androgen-independent, lethal phenotype. A more thorough understanding of telomere biology as it relates to prostate cancer should provide new opportunities for disease prevention, diagnosis, prognostication, and treatment.  相似文献   
36.

Background  

The presence of PCB in caulking (sealant) material found in masonry buildings has been well-documented in several countries. A recent investigation of 24 buildings in the greater Boston area found that 8 buildings had high PCB levels in caulking materials used around window frames and in joints between masonry blocks. Workers removing caulking material have been shown to have elevated serum PCB levels.  相似文献   
37.

Objective  

Many work in injury prone awkward positions that require adequate flexibility and strength in trunk stabilizer muscle groups. Performance on a functional movement screen (FMS) that assessed those factors was conducted and an intervention was designed.  相似文献   
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BACKGROUND: Urban bicycle couriers may have a high incidence of injuries. Most messengers work as contractors and hence their injuries are not well documented. METHODS: To quantify injury rates and severity among urban bicycle couriers a convenience sample of 113 couriers in the city of Boston completed a two-page self-administered survey. RESULTS: Most working couriers have suffered at least one injury resulting either in days lost from work (70%) and in visits to a health-care professional or hospital (55%). The annual incidence rate for injuries resulting in days away from work was 47/100-bike couriers. Bone fractures accounted for the most days lost from work, followed by dislocations, sprains, and strains. Collisions and avoiding collisions with motor vehicles, including being "doored," and collisions with pedestrians accounted for the majority (66%) of events leading to injury. Twenty-four percent of messengers reported wearing a helmet on a regular basis, and 32% have health insurance. CONCLUSIONS: Urban bicycle messengers are a poorly documented, largely unstudied workforce who suffer a very high rate of occupational injury.  相似文献   
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