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631.
To ascertain whether the auditory neocortex also innervates the central nucleus of the inferior colliculus (CNIC) and not only its dorsal (DCIC) and external (ECIC) cortices, the anterograde tracers Phaseolus vulgaris-leucoagglutinin (PHA-L) and biotinylated dextran (BD) were injected into the primary auditory neocortex of albino rats (Te1), and labeled corticocollicular fibers were studied via light and electron microscopy. Axons from discrete regions of Te1 form two rostrocaudally oriented laminar plexuses of terminal fibers in the ipsilateral inferior colliculus (IC) and one in the contralateral IC. The first ipsilateral plexus, located in the medial half of the IC, has a dorsomedial to ventrolateral orientation, parallel to the isofrequency planes of the IC; is continuous through the CNIC and DCIC; and extends into the rostral ECIC. The second plexus is located in the deep layers of the lateral ECIC. These two plexuses meet caudally and ventrally, at the border between the CNIC and the lateral ECIC. The plexus in the contralateral IC is less dense and shorter than the two ipsilateral plexuses and is symmetric to the medial plexus. The thickness of the three plexuses is correlated with the size of the injection site, and their mediolateral and dorsoventral positions change as the injection site in Te1 is displaced rostrocaudally, with more caudal injections resulting in more dorsolateral medial plexuses and more dorsomedial lateral plexuses. Furthermore, the ventromedial border of the IC receives nontopographic, convergent projections from wide regions of rostral portions of Te1. The distribution of these corticocollicular plexuses mimics the topography of previously described intracollicular fibers. Electron microscopy shows that, in all three subdivisions of the ipsilateral IC, corticocollicular fibers form small boutons with features generally associated with excitatory transmission; i.e., they contain round synaptic vesicles and form asymmetric synapses with thin dendritic shafts and spines. These results demonstrate that the auditory corticocollicular projections innervate more extensive regions of the IC than were previously observed. Although peripheral regions receive the densest projection, the entire IC appears to be the target of corticofugal input. © 1996 Wiley-Liss, Inc.  相似文献   
632.
The purpose of this study was to assess the clinical and echocardiographic characteristics of constrictive pericarditis (CP) and restrictive cardiomyopathy (RC) and to compare them with the results obtained with cardiac catheterization. Clinical history, electrocardiogram and X-ray were taken in all patients, and transthoracic and transesophageal echocardiography were performed. Cardiac catheterization with transmyocardial biopsy was performed on only 5 patients. Wall thickness and left ventricular dimensions were normal in all patients with CP. Wall thickness was increased in those with RC. No patients demonstrated alterations in segmental wall movement. The pericardium was thickened and abnormally bright in the 3 patients with CP. In patients with CP the percentage of atrioventricular, semilunar, pulmonary and hepatic flow changes with respiration were more than 10%. In patients with RC this flow variation was less notable. However, the percentage of systolic and diastolic flow velocity increase of hepatic veins during expiration was greater than in CP. We can conclude that M-mode, two dimensional and Doppler echocardiography is extremely useful noninvasive method to differentiate CP and RC with good correlation with cardiac catheterization.  相似文献   
633.
OBJECTIVE: To report a case of Clostridium difficile colitis associated with valaciclovir treatment. CASE SUMMARY: A 73-year-old man with lumbar herpes-zoster started valaciclovir 1 g tid. After three days he began vomiting and developed diarrhea, three to four stools per day. Symptoms worsened over the following days and he was admitted. Valaciclovir was stopped and fluid and electrolyte replacement was started. He continued 6 days later with diarrhea of 7 to 13 stools per day and a stool test for diagnosis of C. difficile infection was performed with a positive result. The patient received oral metronidazole (500 mg/t.i.d. for 10 days) and rapid improvement and eventual resolution of his diarrhea was observed after 3 days of therapy. DISCUSSION: Although no conclusive reports of this reaction exist, we think this is a case of C difficile colitis that appeared three days after valaciclovir was initiated. Colitis improved with metronidazole. Other causes of diarrhea were excluded, such as diabetes mellitus, renal failure, intestinal surgery and intestinal obstruction. Infection was confirmed by a positive test for C. difficile. The application of Naranjo's algorithm asserts the reaction as 'probable'. CONCLUSIONS: Valaciclovir-associated C. difficile colitis, although rare, can have severe consequences for the patient's health. It should be included as a possible adverse effect of valaciclovir treatment by health professionals.  相似文献   
634.
BACKGROUND: There were no previous studies about the quality of cryoprecipitate prepared from fresh‐frozen plasma (FFP) inactivated with amotosalen and ultraviolet A (UVA) light. The aim of this study was to analyze the quantity and quality of coagulation factors in cryoprecipitate prepared from FFP treated with amotosalen and UVA light. STUDY DESIGN AND METHODS: FFP was obtained from whole blood donations and inactivated with amotosalen and UVA light according to the manufacturer's instructions. Fibrinogen, factor VIII (FVIII), von Willebrand factor antigen (VWF : Ag) and activity (VWF : RCo), the von Willebrand factor cleavage protease activity (ADAMTS‐13), and the multimeric structure of VWF were analyzed. RESULTS: The content of fibrinogen, FVIII, and ADAMTS‐13 was lower in cryoprecipitates prepared from amotosalen‐treated plasma when compared with cryoprecipitates prepared from nontreated plasma (35, 40, and 18% loss, respectively). The quantity and quality of VWF as well as VWF multimer patterns were not affected by the inactivation method. CONCLUSION: Cryoprecipitates prepared from amotosalen‐treated FFP contained significantly reduced levels of fibrinogen, FVIII, and ADAMTS‐13. However, the VWF quantity and quality was well preserved.  相似文献   
635.
A total of 48 isoniazid (INH)- and rifampin (RIF)-resistant Mycobacterium tuberculosis isolates, 19 INH-resistant isolates, and 9 RIF-resistant isolates were randomly selected and tested for detecting mutations at codons 315 and 463 of katG by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP), and/or for detecting mutations at a 69-bp region of the rpoB gene by the INNO-LiPA Rif TB assay. Of the 67 INH-resistant isolates tested, 36 (53.7%) showed the mutation at codon 315 of katG; however, none of them showed the mutation at codon 463. The majority of the RIF-resistant samples analyzed (49 of 57, 86.0%) reacted positive with one of the four R-type probes. The R5-pattern (S531L mutation) was the most frequently observed (31 of 57, 54.4%), followed by R4a-pattern (H526Y mutation) 13 isolates (22.8%), R4b-pattern (H526D mutation) 4 isolates (7.0%), and R2-pattern (D516V mutation) 1 isolate (1.8%). Overall, there was agreement between the line probe kit and phenotypic RIF-susceptibility test for 56 (98.2%) of 57 RIF-resistant isolates tested. These results show that the mutation analysis at codon 315 of katG could be used as a screening assay prior to standard susceptibility testing, whereas mutations in the rpoB gene could be used successfully as genetic markers to rapidly detect RIF-resistant M. tuberculosis clinical isolates from northeast Mexico.  相似文献   
636.
This study compared Hispanic children (ages 7 to 11) with combined type (CT, n=33) and inattentive type (IT, n=21) attention deficit hyperactivity disorder (ADHD) and a control group (n=25) on time-estimation and time-reproduction tasks. The ADHD groups showed larger errors in time reproduction but not in time estimation than the control group, and the groups did not differ from each other on their performance on this task. Individual differences could not be accounted for by oppositional-defiance ratings and low math or reading scores. Although various measures of executive functioning did not make significant unique contributions to time estimation performance, those of interference control and nonverbal working memory did so to the time-reproduction task. Findings suggest that ADHD is associated with a specific impairment in the capacity to reproduce rather than estimate time durations and that this may be related to the children's deficits in inhibition and working memory.  相似文献   
637.
BACKGROUND: Interferon (IFN) regimens for HCV treatment are less effective in HCV/HIV-coinfected patients. There are no effective treatments for patients who fail IFN therapies. We examined the safety and efficacy of peginterferon alfa-2a (peg-IFNalpha-2a) plus ribavirin (RBV) in 41HCV/HIV-coinfected patients non-responsive to prior IFN treatment. METHODS: Patients received peg-IFNalpha-2a (180mg/week) plus RBV (800mg/day) for 24 weeks (n=41). At week 24, patients with non-detectable HCV RNA or > or =2-log decrease from baseline, received peg-IFNalpha-2a (180mg/week) plus RBV (800mg/day) for 24 weeks further. Patients not responding to treatment at week 24 were discontinued. RESULTS: Intent to treat (ITT) sustained viral response (SVR) was 21.9%. Patients who received at least 24 weeks of peg-IFNalpha-2a plus RBV treatment (n=35), SVR rates were 25.7%. SVR was associated with significant improvements in liver histology grade (p=0.02), stage (p=0.02), and fibrosis progression rate (FPR) (p=0.03). Patients that failed to achieve SVR had statistically significant decreases in grade (p=0.09) and FPR (p=0.01). CONCLUSION: peg-IFNalpha-2a plus RBV is effective and safe to achieve SVR in HCV/HIV coinfected patients non-responsive to prior IFN treatment. Patients that achieve SVR have significant improvements in liver histology parameters. In patients that do not achieve SVR there are histological benefits beyond virological response that suggest that peg-IFNalpha-2a+RBV therapy may decrease risk of progression to end stage liver disease.  相似文献   
638.
BACKGROUND: Complex malformations of the female genital tract are often incorrectly identified, treated and reported, probably due to not considering the malformation as a cause of the clinical symptoms and neither the embryological origin of the different elements of the genitourinary tract. METHODS: Complex malformations are studied and classified, and new types are presented. The new types of complex malformations presented are: (i) Cases of unilateral vaginal or cervico-vaginal atresia with renal agenesis and uterine duplication, with or without communication between hemiuteri; (ii) the unilateral Rokitansky syndrome; and (iii) the combination in the same patient of unilateral Rokitansky syndrome (Müllerian defect) on one side and blind vagina and ipsilateral renal agenesis syndrome (Wolffian defect) on the other side. RESULTS: A revised version of the clinical and embryological classification of genital malformations is presented and an associated diagram points out the origin of these malformations. CONCLUSIONS: These genital malformative anomalies reaffirm our hypothesis about the embryology of the human vagina as deriving from the Wolffian ducts and the Müllerian tubercle; and they show that gynecologists should be aware of the related symptoms and the embryology of the female genital tract in order to achieve a better comprehension of the malformations for their right correction or therapeutic approach.  相似文献   
639.
PURPOSE: The purpose of this study is to describe a patient with retinal angiomatous proliferation (RAP) treated successfully by photodynamic therapy. METHODS: A 74-year-old white woman was referred to our clinic for evaluation as a result of progressive decrease of vision in the right eye. Visual acuity was 20/100 in the affected right eye. The findings of fluorescein and indocyanine green angiography were consistent with a diagnosis of RAP, and cystoid macular edema was also revealed by optical coherence tomography (OCT). Photodynamic therapy (PDT) was carried out because of visual deterioration and localization of the RAP. RESULTS: The RAP was treated with PDT, and an improvement in visual acuity to 20/60 was noted 4 months after treatment and 20/40 after 6 months. The resolution of the lesion was confirmed by fluorescein angiography, indocyanine green angiography, and OCT. CONCLUSIONS: Photodynamic therapy can be effective for the treatment of RAP when it is associated with visual acuity decrease and is located near the fovea.  相似文献   
640.
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