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11.
Although Parkinson’s disease (PD) and essential tremor (ET) are distinct clinical disorders, their coexistence can sometimes cause diagnostic problems. In this study, we conducted detailed investigations of patients with both ET and PD (ET–PD) and compared their clinical and cognitive profiles with those of patients with only ET or only PD. This study examined three groups of patients: the first group had ET–PD concomitantly (n = 9); the second group had only ET (n = 9); the third group had only PD (n = 10). The groups were compared in terms of demographic characteristics, clinical features, and cognitive functions. With the exception of positive family histories, which were more common in ET–PD than in PD patients, we found no differences among the groups with respect to demographic characteristics (p = 0.044). PD-only patients had more akinetic-rigid type Parkinsonism (p = 0.016), and their levodopa response was better than that of ET–PD patients (p = 0.017). Patients with ET–PD obtained significantly lower scores than those with pure ET on several cognitive tests, suggesting a prominent frontal-type cognitive dysfunction. In conclusion ET–PD patients differed from PD patients, showing more frequent familial tremor histories and lower levodopa responsiveness. This patient population also demonstrated more severe cognitive impairments than pure-ET patients. This result suggests that ET–PD patients are a subset of ET patients with more widespread neurodegeneration, which may indicate the presence of a syndrome that includes overlap between ET and PD.  相似文献   
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13.
Directed migration of diverse cell types plays a critical role in biological processes ranging from development and morphogenesis to immune response, wound healing, and regeneration. However, techniques to direct, manipulate, and study cell migration in vitro and in vivo in a specific and facile manner are currently limited. We conceived of a strategy to achieve direct control over cell migration to arbitrary user-defined locations, independent of native chemotaxis receptors. Here, we show that genetic modification of cells with an engineered G protein-coupled receptor allows us to redirect their migration to a bioinert drug-like small molecule, clozapine-N-oxide (CNO). The engineered receptor and small-molecule ligand form an orthogonal pair: The receptor does not respond to native ligands, and the inert drug does not bind to native cells. CNO-responsive migration can be engineered into a variety of cell types, including neutrophils, T lymphocytes, keratinocytes, and endothelial cells. The engineered cells migrate up a gradient of the drug CNO and transmigrate through endothelial monolayers. Finally, we demonstrate that T lymphocytes modified with the engineered receptor can specifically migrate in vivo to CNO-releasing beads implanted in a live mouse. This technology provides a generalizable genetic tool to systematically perturb and control cell migration both in vitro and in vivo. In the future, this type of migration control could be a valuable module for engineering therapeutic cellular devices.The ability of many cell types to migrate long distances within the body and specifically localize to target sites of action is critical for their proper function. For example, immune cells rapidly home to sites of infection, concentrating their powerful cytotoxic and proinflammatory activities for maximum efficacy while limiting damage to healthy tissue. In morphogenesis, cells undergo a complex stereotyped process involving migration as well as proliferation, differentiation, and programmed cell death to produce fully developed multicellular structures. In wound healing and regenerative processes, stem and progenitor cells home to injured tissues from nearby sites—as well as from distant locations including the bone marrow—to provide a stream of new cells to replenish and provide trophic support to old and damaged cells.Cell migration is also an important factor to consider in the use of cells as therapeutic agents. The use of cells for the treatment of a growing array of diseases including cancer, autoimmunity, and chronic wounds is currently being explored (16). The appropriate and efficient localization of therapeutic cells to sites of disease has been identified as an important factor for successful cell-based therapy (717). However, preclinical studies and clinical trials to date have shown that the homing to sites of disease of many cell types commonly used as therapeutics is frequently impaired or limited, especially after ex vivo expansion of cells in culture (7, 12, 18, 19).The ability to redirect the migration of cells to any user-specified location in the body would be a powerful enabling technology for basic research as well as for future applications, but there are currently few easily generalizable strategies to accomplish this goal. We conceived of an approach to direct cellular homing to small molecules by expressing, in motile cells, engineered G protein-coupled receptors (GPCRs) called receptors activated solely by a synthetic ligand (RASSLs) (20, 21).RASSLs are engineered to be unresponsive to endogenous ligands but can be activated by pharmacologically inert orthogonal small molecules (Fig. 1A). Versions of these receptors exist for the three major GPCR signaling pathways (Gαs-, Gαi-, and Gαq-coupled receptors), and the design of a new arrestin-biased variant has recently been reported (21, 22). Because GPCRs control many important physiological functions, including cell migration, we hypothesized that, by expressing these engineered receptors in motile cells, we could develop a general strategy for establishing user control over cell homing (Fig. 1B). Here, we use a family of second-generation RASSLs, known as designer receptors exclusively activated by a designer drug (DREADDs), that are activated only by the small molecule clozapine-N-oxide (CNO), an inert metabolite of the FDA-approved antipsychotic drug clozapine (Fig. S1) (20). CNO is highly bioavailable in rodents and humans, lacks affinity for any known receptors, channels, and transporters, and does not cause any appreciable physiological effects when systemically administered in normal mice (20, 23, 24).Open in a separate windowFig. 1.Engineered Gαi-coupled GPCRs Di3 and Di mediate cytoskeletal changes and chemotaxis of HL-60 neutrophils in response to CNO. (A) RASSLs are engineered GPCRs that interact orthogonally with a bioinert small-molecule drug. Natural ligands do not interact with the engineered receptors, and the bioinert drug that activates the engineered receptors does not interact with native receptors. (B) We tested whether certain second-generation RASSLs known as DREADDs could mediate cell motility. (C) Changes in electrical impedance that result from cell spreading in response to drug or ligand are detected by an electrode array. HL-60 neutrophils transiently transfected to express engineered GPCRs were plated on fibronectin-coated impedance assay plates and stimulated with vehicle control, 100 nM fMLP (positive control chemoattractant) or 100 nM CNO. All cells responded to fMLP whereas only Di3- or Di-expressing cells responded to CNO. Mean ± SEM for n = 3 replicates is shown. (D) Cell migration of HL-60 neutrophils transiently transfected with engineered GPCRs was quantitated in a porous transwell Boyden-chamber assay. All cells migrated in response to fMLP whereas only Di3- or Di-expressing cells migrated in response to CNO. Drug concentrations used: 100 nM CNO, 100 nM fMLP. Mean ± SEM for n = 3 replicates is shown. (E) Polarization and cell migration in neutrophils involves Rac and PI3K activation. Di-expressing HL-60 neutrophils were treated with 100 nM fMLP or 100 nM CNO before immunoblotting for phosphorylated Akt and phosphorylated PAK as readouts for PI3K and Rac activity, respectively. Peak levels of phospho-Akt and phospho-PAK are shown for each condition. Both were increased by CNO stimulation in Di cells but not in control cells (P < 0.01 by Student t test). Stimulation with fMLP increased phospho-Akt and phospho-PAK levels in both Di and control cells (P < 0.01 by Student t test), but Di cells showed higher peak levels of phospho-Akt than did control cells (P < 0.01 by Student t test). Three (for CNO) or four (for fMLP) independent experiments were performed and mean ± SEM are shown.  相似文献   
14.
The neurologic dysfunctions caused by treatment may affect health and quality of life in survivors of childhood leukemia. The objective of this study was to identify the neuropsychological late effects of leukemia treatment to provide an assessment about the degree and incidence of these late effects. Neurological and ophtalmological examination, cranial magnetic resonance imaging (MRI), auditory and neurocognitive tests, and questionnaires of quality of life were performed to 44 acute leukemia survivors at least 5 years after diagnosis. Median time since completion of chemotherapy was 7.5 years (2–18) and median age at the time of the study was 16.4 years (8–31). At least one or more late effects detected by physical examination (PE), neurological tests, or neurocognitive tests encountered in 80% of the patients, and 64% of the patients specified at least one complaint in the quality of life questionnaire. MRI revealed pathological findings in 18% and electroencephalogram (EEG) abnormalities were present in 9% of the patients. Evaluation of total intelligence scores revealed that 30% of patients’ IQ scores were <80 and 70% of the patients’ scores demonstrated neurocognitive dysfunctions. The patients >6 years at the time of diagnosis were found to have more psychological problems and higher rates of smoking and alcohol consumption. The most frequent complaint was headache and the most common problem in school was denoted as difficulty in concentration. Our study demonstrated that most of the survivors of childhood leukemia are at risk of developing neuropsycological late effects.  相似文献   
15.

Background

Osteonecrosis of the jaw (ONJ) related to toxic effects of illicit drugs such as cocaine is not very common and might be overshadowed today by the incidence of bisphosphonate-related osteonecrosis of the jaw. However, we present a case which suggests a close relationship between abuse of the illicit drug methamphetamine (MA) and ONJ.

Case report

A 44-year-old male with extended osteonecrosis of the maxilla admitted chronic abuse and synthesis of MA for at least the previous two decades. Furthermore, he confessed self-extracting teeth since he became addicted to MA. However at presentation, he had been successfully cured of his addiction to MA. A step-by-step surgical treatment was planned using computer-aided design/computer-aided manufacturing techniques. After resection of necrotic bone, a vascularized osteomyocutaneous fibular flap was applied secondarily.

Discussion

Two possible mechanisms, alone or in combination, could possibly lead to MA-related ONJ. Self-extraction of teeth as a psychopathologic behavior of self-destruction among MA abusers results in wounds that allow unhindered invasion of microorganisms causing osteomyelitis and ONJ, while on the other hand, the heating of white phosphor releases toxic phosphorous vapor, which could be inhaled and consequently cause ONJ of the maxilla. However, since the worldwide prevalence of MA abuse is remarkably high, a relationship between MA abuse and ONJ will offer a new aspect in the etiology of ONJ and might present a further therapeutic challenge.  相似文献   
16.

Background

Today, virtually planned surgery and computer-aided designed/computer-aided manufactured (CAD/CAM) tools to reconstruct bony structures are being increasingly applied to maxillofacial surgery. However, the criteria for or against the usage of the CAD/CAM technique are disputable, since no evidence-based studies are available. Theoretically, the CAD/CAM technique should be applied to complex cases. In this case report, we present our experiences and discuss the criteria for application.

Case report

Three cases are reported in which subjects received an osseous reconstruction using CAD/CAM techniques. In the first case, resection of the mandibular body and ramus was carried out, and reconstruction with a vascularised iliac bone transplant was performed. During surgery, a repositioning of the ipsilateral condyle was necessary. The second case comprised a wide mandibular reconstruction together with a repositioning of the condyles and the soft tissue chin using a two-segment osteomyocutaneous fibula flap. In the third case, a two-flap technique consisting of a double-barrelled osseous fibula flap and a radial forearm flap was applied to cover a wide palatine defect.

Conclusion

Our experience suggests that the CAD/CAM technique provides an accurate and useful treatment not only in complex cases, but also in simpler ones, to achieve an anatomically correct shape of the bone transplant and to reposition adjacent structures.  相似文献   
17.
This study aimed to explore the experiences of the people who underwent orthopedic surgery under spinal anesthesia and to report their feelings and thoughts. The study was carried out using a qualitative approach. Twenty‐one patients were interviewed who underwent orthopedic surgery on the first or second postoperative day. Content analysis was performed after the collection of raw data. NVIVO 12 Pro software was used for data analysis. The frequency count (f) and participant codes (P) were used for the presentation of the findings. The themes and frequency counts obtained by analyzing the interviews with the patients were as follows: “Time passed like watching a movie” (f = 213), “Like an adventure” (f = 587), and “See, feel, look” (f = 405). Five of 21 participants (23.8%) stated that they would not recommend spinal anesthesia. The findings generally indicated the anxiety caused by the unknown, fear in the preanesthetic period, operation experienced like an adventure, and a process generally completed with satisfaction.  相似文献   
18.
Prolidase deficiency   总被引:1,自引:0,他引:1  
A 32‐year‐old mentally retarded woman was admitted to hospital with recurrent ulcers on her legs, which appeared for the first time at 8 years of age. Apart from recurrent lower respiratory tract infections and chronic otitis media, her personal history was unremarkable. Her parents were second‐degree relatives. The family history showed no similar disease or mental retardation. Physical examination revealed that the patient had an unusual facial appearance, with a high‐arched palate; she had multiple tooth caries ( Fig. 1 ).
Figure Figure 1  Open in figure viewer PowerPoint Facial appearance of the patient  相似文献   
19.
Primary renal lymphoma and xanthogranulomatous pyelonephritis in childhood   总被引:3,自引:0,他引:3  
Primary renal non-Hodgkin's lymphoma is very rare in childhood. A six-year-old boy presented with bilateral non-obstructive multinodular nephromegaly and renal failure. Percutaneous needle biopsy showed large-cell lymphoma. The patient was started on chemotherapy. A right nephrectomy was done when systemic hypertension developed in the presence of a non-functional right kidney. Histopathologic examination revealed focal lymphomatous infiltration and xanthogranulomatous pyelonephritis which is an atypical form of chronic renal infection. The case is discussed in relation to previons reports.  相似文献   
20.
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