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101.
102.
Tuberculosis (TB) in South American camelids (SAC) is caused by Mycobacterium bovis or Mycobacterium microti. Two serological methods, rapid testing (RT) and the dual-path platform (DPP) assay, were evaluated using naturally infected SAC. The study population included 156 alpacas and 175 llamas in Great Britain, Switzerland, and the United States. TB due to M. bovis (n = 44) or M. microti (n = 8) in 35 alpacas and 17 llamas was diagnosed by gross pathology examination and culture. Control animals were from herds with no TB history. The RT and the DPP assay showed sensitivities of 71% and 74%, respectively, for alpacas, while the sensitivity for llamas was 77% for both assays. The specificity of the DPP assay (98%) was higher than that of RT (94%) for llamas; the specificities of the two assays were identical (98%) for alpacas. When the two antibody tests were combined, the parallel-testing interpretation (applied when either assay produced a positive result) enhanced the sensitivities of antibody detection to 89% for alpacas and 88% for llamas but at the cost of lower specificities (97% and 93%, respectively), whereas the serial-testing interpretation (applied when both assays produced a positive result) maximized the specificity to 100% for both SAC species, although the sensitivities were 57% for alpacas and 65% for llamas. Over 95% of the animals with evidence of TB failed to produce skin test reactions, thus confirming concerns about the validity of this method for testing SAC. The findings suggest that serological assays may offer a more accurate and practical alternative for antemortem detection of camelid TB.  相似文献   
103.
Death does not occur instantaneously and organs do not decompose at the same rate or in the same way. Nulligravid human uteri and prostate glands are the last internal organs to deteriorate during decomposition; however, the reason for this very important observation is still enigmatic. Recent studies have elucidated that the composition and abundance of microbes in the human thanatomicrobiome (microbiome of death) varies by organ and changes as a function of time and temperature. The ileocecal area has the largest absolute postmortem burden that spreads to the liver and spleen and continues to the heart and brain depending on the cause of death. To truly understand the mechanisms of microbial assembly during decomposition, a thorough examination of different strategies utilized by the trillions of microbes that colonize decaying tissues is needed from a multi-organ and multidisciplinary approach. In this review, we highlight interdisciplinary research and provide an overview of human decomposition investigations of thanatomicrobiomic changes in internal organs.  相似文献   
104.
This review is a journey of the landmark erythroblast macrophage protein (Emp) discovered in 1994, and it walks chronologically through the progress that has been made in understanding the biological function of this protein. Historically, Emp was the first identified cell attachment molecule and is expressed in both erythroblasts and macrophages and mediates their attachments to form erythroblastic islands. The absence of Emp erythroblasts shows defects in differentiation and enucleation. Emp‐deficient macrophages display immature morphology characterized by small sizes, round shapes, and the lack of cytoplasmic projections. Although the primary sequence of Emp has already been determined and its role in both erythroid and macrophage development is well established, there are major gaps in the understanding of its function at the molecular level. Recent studies had implicated its importance in actin cytoskeleton remodeling and cell migration, but the molecular mechanisms are still enigmatic. Previous studies have also demonstrated that downregulation of Emp affects the expression of mitogen‐associated protein kinase 1 (MAPK1) and thymoma viral protooncogene (AKT‐1) resulting in abnormal cell motility. In this review, we summarize the proposed function of Emp based on previous studies, present scenarios, and its plausible future in translational research.  相似文献   
105.

Purpose

The main challenge of intramedullary nail (IM-nail) fixation surgery is to achieve the X-ray shot in which the distal holes of the IM-nail appear as circles (desired view); screw insertion is then performed. Although C-arm X-ray devices are routinely used in IM-nail fixation procedures, the surgeons or radiation technologists (rad-techs) usually utilize them in a trial-and-error manner. This increases both radiation exposure and surgery time. This study addresses the problem by presenting a C-arm-based IM-nail pose recognition method.

Methods

The specific purpose of this study was to develop and validate an automated technique for identifying the current pose of the IM-nail relative to the C-arm. An accuracy assessment is performed to test the reliability of the navigation results. The algorithm starts with a sequential biplanar set of X-ray imagery (acquired from a tracked C-arm) of the distal part of an inserted IM-nail. The image-processing module then extracts features of interest, and a mathematical model incorporates them to calculate the six degree-of-freedom position and orientation parameters of the nail.

Results

Translational accuracy was demonstrated to be better than 0.5 mm, rotational accuracy for roll and pitch to be better than \(2^{\circ }\) and for yaw to be better than \(2.5^{\circ }\) depending on the separation angle. Computation time was less than 0.5 s.

Conclusion

An IM-nail distal locking navigation technique is introduced in this study that leads to more accurate and faster screw placement with a lower consumption of radiation dose and a minimum number of added steps to the operation.
  相似文献   
106.

Background

The pulmonary arterial wedge pressure (PAWP) response to exercise may unmask latent heart failure with preserved ejection fraction. There remains a lack of consensus over threshold values for PAWP during exercise. A systematic review of studies examining PAWP by means of right heart catheterization at rest and during exercise in healthy individuals was performed.

Methods and Results

Relevant data derived from healthy volunteers were stratified by age (older than 40 years vs 40 years or younger) and sex. Three exercise intensities were predefined: light, moderate, and strenuous. Weighted means and weighted 95% confidence intervals (CIs) for the aggregate data were calculated. A total of 424 individuals from 32 unique studies were included, of which 19% (n?=?82) were female. PAWP reached weighted mean and 95% CI values of 19 (17–21) and 17 (16–18) mm Hg at light and moderate exercise, respectively. The PAWP response to exercise was similar between men and women >40 years of age. However, exercise intensities were lower in women.

Conclusions

PAWP increases during exercise, reaching up to 20 mm Hg in adults >40 years of age. Older women achieve PAWP values similar to those of older men, but at lower intensities. Findings support a threshold of at least 25 mm Hg as an absolute cutoff value for “normal” PAWP response to exercise in individuals >40 years old.  相似文献   
107.
From 680 surgical specimens of thyroid disease, 31 cases of thyroid carcinoma found at Howard University Hospital, from January 1950 to December 1975, are reviewed. Eighteen (58 percent) were females and 13 (42 percent) were males. Of the 31 patients, there were 11 patients with follicular carcinoma, 11 with papillary carcinoma, seven with mixed papillary and follicular carcinoma, one with Hurthle cell carcinoma, and one with medullary carcinoma. Thyroid carcinoma accounts for only .001 percent of all admissions during the period of study, and is indeed a rare cause of disease among blacks at this institution. Recommendations for surgery and follow-up data are presented.  相似文献   
108.

Background

Adequate pain control through sedation and anesthesia for emergency procedures is a crucial aspect of pediatric emergency care. Resources for administering such anesthesia are extremely limited in many low-income settings.

Methods

Non-anesthetist providers in Western Kenya were trained in the use of a ketamine-based sedation and anesthesia package for non-anesthetists, Every Second Matters for Mothers and Babies-Ketamine? (ESM-Ketamine). Data on use and safety of this package for emergent and urgent pediatric procedures was collected. Providers were surveyed as to what they would have done for similar procedures if the ESM-Ketamine package were unavailable.

Results

Ninety procedures were completed for 77 pediatric patients utilizing the ESM-Ketamine package. Of these, 29 (32.2 %) cases were orthopedic reductions, 19 (21.1 %) were incision and drainage, and 19 (21.1 %) were debridement and irrigation of burns. Remaining cases included cesarean section, repair of perineal tear, foreign body removal, arthrocentesis, laceration repair, exploratory laparotomy, excision of mass, paracentesis, and circumcision. There were no serious adverse events in any of the cases, 17 % experienced minor adverse events including hypersalivation, hallucinations, or brief, self-resolving, oxygen desaturations. Providers were surveyed for 80 of the 90 cases as to what they would have done in the absence of the ESM-Ketamine package: in 26 cases (32.5 %), they reported they would proceed with the procedure without any anesthesia or analgesia; in 15 (18.75 %), they reported they would significantly delay the procedure while waiting for an anesthetist; in 13 (16.25 %), they reported they would attempt referral to another facility; and in 26 (32.5 %), they reported they would try using an alternate form of analgesia, primarily acetaminophen, ibuprofen, diclofenac, and/or diazepam. All surveyed providers reported they would use the ESM-Ketamine package again in similar cases.

Conclusions

The ESM-Ketamine package, through the use of a simplified protocol and checklist, allows for safe analgesia and anesthesia in children by non-anesthetists in a resource-limited setting for selected emergent and urgent procedures. This package addresses a significant gap in the availability of anesthesia services in low-income settings that would otherwise result in significant delays to procedures or proceeding with painful procedures with inadequate analgesia.
  相似文献   
109.
The clinical spectrum of Buerger’s disease (TAO; thromboangiitis obliterans) seems to be changing. Considering the lack of any formal studies on the epidemiology of this disease in Iran, we evaluated the data of 198 confirmed cases of TAO during the period 1996–2006. Diagnosis was based on Papa’s scoring system. All patients were male and aged at the time of diagnosis 40.5 ± 10.1 years. All patients were smokers for a duration of 22.2 ± 11.6 years. There was a strong seasonal variation for admission with winter admissions being significantly the most common (P < 0.001). Patients, 181 (91.4%), had only lower limb involvement, 4 (2.0%) had solely upper limb disease, and 13 (6.6%) suffered from both. Sympathectomy, amputation, and bypass graft surgery were performed in 97 (49.0%; lumbar: 92, thoracic: 5), 71 (35.9%), and 28 (14.1%) patients, respectively. The present report is the second one to show seasonal variation in TAO.  相似文献   
110.
Low-frequency stimulation (LFS) has antiepileptogenic effects on kindled seizures. In the present study, the role of galanin receptors in the inhibitory effect of LFS on perforant path kindling acquisition was investigated in rats. Animals were kindled by perforant path stimulation in a rapid kindling manner (six stimulations per day). LFS (0.1 ms pulses at 1 Hz, 600 pulses, and 80-150 microA) was applied immediately after termination of each kindling stimulation. M35 (0.5 and 1.0 nM per site), a nonselective galanin receptor antagonist and M871 (1.0 microM per site), a selective galanin receptor type 2 (GalR2) antagonist, were daily microinjected into the dentate gyrus before starting the stimulation protocol. The expression of GalR2 in the dentate gyrus was also investigated using semi-quantitative RT-PCR. Application of LFS significantly retarded the kindling acquisition and delayed the expression of different kindled seizure stages. In addition, LFS significantly reduced the increment of daily afterdischarge duration during kindling development. Intra-dentate gyrus microinjection of both M35 and M871 significantly prevented the inhibitory effects of LFS on kindling parameters. During the focal kindled seizure stages (1-3) M871 had no significant effect. However, during generalized seizure stages (4 and 5), M871 had the same effect as M35. Semi-quantitative RT-PCR also showed that after kindling acquisition, the GalR2 mRNA level decreased in the dentate gyrus but application of LFS prevented this decrease. Obtained results show that activation of galanin receptors by endogenous galanin has a role in mediating the inhibitory effect of LFS on perforant path-kindled seizures. This role is exerted through GalR1 during focal- and through GalR2 during generalized-kindled seizures.  相似文献   
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