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81.
A study was undertaken to determine the most effective method of pacemaker follow-up in terms of the total number of complications detected and yield per follow-up in single and dual chamber pacing systems. The analysis involved 9,786 patient records from 635 patients. The records were reviewed with respect to method of follow-up, number of chambers paced, and complications detected. Complications included: oversensing, undersensing, noncapture, pocket and diaphragmatic stimulation, pacemaker mediated tachycardia, crosstalk, pulse generator malfunction, lead malfunction, infection/erosion, premature end of service, exit block, and other miscellaneous problems. Eight thousand two hundred eighty-eight of the 9,786 follow-ups were performed in the office while 1,498 were transtelephonic. Single chamber pacing systems were implanted in 329 patients and 306 were dual chamber systems. A total of 599 complications were detected. Analysis yielded a per patient complication rate of 5.1 % (single chamber) and 8.4% (dual chamber) for in-office follow-up. This compared to a transtelephonic follow-up per patient complication rate of only 0.3% (single chamber) and 1.0% (dual chamber). In-office pacemaker follow-up is significantly more effective (P < 0.001) than transtelephonic follow-up in detecting both single and dual chamber pacemaker system complications.  相似文献   
82.
Encainide was evaluated in 26 patients undergoing programmed electrical stimulation (PES) for ventricular arrhythmias. These patients had inducible symptomatic ventricular tachyarrhythmias during baseline PES and had previously failed a mean of 3.2 antiarrhythmic agents. Encainide was discontinued in six patients prior to PES because of spontaneous ventricular tachycardia (VT) (five patients) and adverse effect (one patient). Encainide increased, the PR, QRS, QTc intervals, and right ventricular effective refractory period (RVERP) significantly from baseline (P < 0.05) in 16 patients who were extensive metabolizers. Encainide, at a mean dose of 110 ± 28 mg/day increased the ventricular tachycardia cycle length (VTCL) from 278 ± 77.1 msec to 334 ± 68.8 msec (P < 0.05). Encainide alone was effective (< 15 beats induced) or partially effective (converting inducible sustained VT to < 15 beats asymptomatic nonsustained VT or increasing the VTCL < 100 msec with no symptoms) in two and seven patients respectively. In seven patients, encainide was also reevaluated at a higher dose (mean dose 148 ± 22 mg/day), but this dose did not significantly alter the overall response or measured parameters. Seven patients were subsequently evaluated on combination of encainide and another antiarrhythmic agent. The combination was effective in three patients and partially effective in three patients. Serum concentrations were measured during each testing period; a moderate correlation was observed between the PR and RR intervals and total concentrations in patients who were extensive metabolizers. Eleven patients who were effective or partially effective during acute testing were placed on long-term encainide therapy (three patients alone and eight patients on combination therapy). In a mean follow-up of 8.9 months (1–25 months) encainide was discontinued in five patients (two patients due to nonsudden cardiac death, one patient due to recurrent nonfatal VT, and two patients due to side effects of combination therapy.) Conclusion: Encainide alone is minimally effective (7.7%) for preventing inducible ventricular tachycardia, but partially effective in 38.9%. Retesting at a higher dose does not offer any additional benefit. However, encainide in combination with another antiarrhythmic agent may improve the response in patients who remain inducible on encainide alone. Further studies are needed to verify this observation.  相似文献   
83.
Fibronectin in synovial fluid and tissue in rheumatoid arthritis   总被引:10,自引:0,他引:10  
Fibronectin is a glycoprotein found in body fluids, loose connective tissue matrix and in basement membranes. Fibronectin in rheumatoid arthritis synovial fluid was immunologically indistinguishable from the plasma form, as shown by double-diffusion analysis. Fibronectin isolated from rheumatoid synovial fluid by affinity chromatography on gelatin--Sepharose had a polypeptide pattern similar to that of plasma fibronectin in SDS--polyacrylamide gel electrophoresis. In fifty-one patients with rheumatoid arthritis and related diseases fibronectin concentrations is synovial fluid were 445 +/- 103 micrograms/ml (mean +/- SD) and within normal range, 335 +/- 52 micrograms/ml, in plasma. Immunofluorescence staining showed a prominent increase of fibronectin in the proliferating synovial connective tissue in rheumatoid arthritis as compared to normal synovial membrane. The results suggest an increased local production of fibronectin in rheumatoid synovial tissue.  相似文献   
84.
McCash SI, Unger P, Dillon R, Xiao G‐Q. Undifferentiated carcinoma of the renal pelvis with osteoclast‐like giant cells: a report of two cases. APMIS 2010; 118: 407–12. Undifferentiated carcinoma with osteoclast‐like giant cells arising in the urothelium of the bladder or upper urinary tract is an extremely rare entity. The majority of cases found in the renal pelvis and bladder are associated with either an in situ urothelial malignancy or a conventional high‐grade urothelial carcinoma. These malignancies tend to behave poorly with a grim prognosis and course. We report two additional cases of undifferentiated carcinoma with osteoclast‐like giant cells of the renal pelvis in two patients disease free 42 and 18 months after surgical treatment, respectively.  相似文献   
85.
Sleep fragmentation is a common symptom in sleep disorders and other medical complaints resulting in excessive daytime sleepiness. The present study seeks to explore the effects of sleep fragmentation on learning and memory in a spatial reference memory task and a spatial working memory (WM) task. Fischer/Brown Norway rats lived in custom treadmills designed to induce locomotor activity every 2 min throughout a 24-h period. Separate rats were either on a treadmill schedule that allowed for consolidated sleep or experienced no locomotor activation. Rats were tested in one of two water maze-based tests of learning and memory immediately following 24 h of sleep interruption. Rats tested in a spatial reference memory task (eight massed acquisition trials) with a 24-h follow-up probe trial to assess memory retention showed no differences in acquisition performance but were impaired on the 24 h retention of the platform location. In contrast, the performance of rats tested in a spatial WM task (delayed matching to position task) was not impaired. Therefore, sleep fragmentation prior to testing impairs the ability to retain spatial reference memories but does not impair spatial reference memory acquisition or spatial WM in Fischer-Norway rats.  相似文献   
86.
Formation of CD4–gp160 intracellular complexes represents an important mechanism leading to the induction of receptor interference. Previous studies have demonstrated that cells coexpressing gp160 and CD4 formed complexes of CD4 and gp160 which became blocked within the endoplasmic reticulum (ER), preventing CD4 from reaching the cell surface. In this report we have investigated the domains and residues of CD4 and gp160 involved in intracellular interaction. Accordingly, we have introduced mutations in both CD4 and gp160 at sites previously shown to disrupt CD4–gp120 interactions at the cell surface. Using a T7-vaccinia virus transient expression system, we expressed these gp160 and CD4 mutants in HeLa cells and analyzed their effects on intracellular complex formation and CD4 surface modulation. We observed that a number of gp160 mutants which failed to interact with CD4 at the cell surface also failed to bind and trap CD4 within the ER as expected. However, mutations at a critical residue, W427, did not abrogate intracellular CD4 binding. These gp160 mutants continued to interact with intracellular CD4 and inhibit CD4 transport to the cell surface, although gp120 produced from these mutants did not bind CD4 at the cell surface as expected. A number CD4 mutants also continued to form intracellular complexes with gp160, resulting in the loss of CD4 surface expression. Again, these CD4 mutants did not bind to gp120 at the cell surface, consistent with earlier reports. These results demonstrate that intracellular interactions between gp160 and CD4 in the ER may utilize different contact sites compared to those used during CD4 and gp120 binding at the cell surface. The data provide further evidence that the environment in which CD4 and the HIV-1 envelope glycoprotein interact can have a significant effect on their interaction.  相似文献   
87.
Sleep disturbances are a hallmark feature of post‐traumatic stress disorder (PTSD), and associated with poor clinical outcomes. Few studies have examined sleep quantitative electroencephalography (qEEG), a technique able to detect subtle differences that polysomnography does not capture. We hypothesized that greater high‐frequency qEEG would reflect ‘hyperarousal’ in combat veterans with PTSD (n = 16) compared to veterans without PTSD (n = 13). EEG power in traditional EEG frequency bands was computed for artifact‐free sleep epochs across an entire night. Correlations were performed between qEEG and ratings of PTSD symptoms and combat exposure. The groups did not differ significantly in whole‐night qEEG measures for either rapid eye movement (REM) or non‐REM (NREM) sleep. Non‐significant medium effect sizes suggest less REM beta (opposite to our hypothesis), less REM and NREM sigma and more NREM gamma in combat veterans with PTSD. Positive correlations were found between combat exposure and NREM beta (PTSD group only), and REM and NREM sigma (non‐PTSD group only). Results did not support global hyperarousal in PTSD as indexed by increased beta qEEG activity. The correlation of sigma activity with combat exposure in those without PTSD and the non‐significant trend towards less sigma activity during both REM and NREM sleep in combat veterans with PTSD suggests that differential information processing during sleep may characterize combat‐exposed military veterans with and without PTSD.  相似文献   
88.
In today's dental literature, most frequently, esthetics are addressed with fixed restorations. This article will illustrate the opportunity to provide our patients with very good esthetic outcomes with a hopeless dentition utilizing dental implants, laser-welded titanium components, and characterized acrylic resin prostheses. The definitive prostheses provide excellent facial support, phonetics, esthetics, smile line, and function. The steps in such a treatment will be presented from the clinical to dental laboratory procedures.

CLINICAL SIGNIFICANCE


Incorporating newer technology into our patient treatment plans, which increasingly includes dental implants, may allow more time-efficient, esthetic, predictable, and reliable treatment. Laser-welded titanium frameworks offer many advantages for the patient, clinician, and dental technician, which are illustrated.  相似文献   
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