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101.
A general consensus exists that the presynaptic terminals in the hippocampal CA1 area are resistant to ischemic stress in spite of the loss of their target cells (CA1 pyramidal neurons). We have verified this by immunostaining and Western immunoblotting using the antibodies for presynaptic proteins, synaptosomal-associated protein of 25 kDa (SNAP-25) and synaptophysin in gerbils after bilateral carotid artery ligature. In the immunohistochemical analysis, decreases in SNAP-25 and synaptophysin immunoreactivities in the strata radiatum and oriens, especially around the apical dendrite of CA1 neurons, and disappearance of SNAP-25 immunoreactivity in the alveus were observed on day 2 after ischemia. On days 7 and 14, SNAP-25-positive granular materials were expressed in the CA1 area, and intense synaptophysin immunoreactivity around surviving CA1 neurons was observed. Western immunoblot analysis revealed significant decreases of SNAP-25 and synaptophysin (about 60% of control levels) on day 2, and then increase of their proteins (130–140% of control levels) on day 14. These results indicate that presynaptic degeneration occurs in the hippocampal CA1 area after ischemia, and it precedes the delayed neuronal death of CA1 neurons. The presynaptic terminal damage may be responsible for some pathological changes in ischemic brains.  相似文献   
102.
Performing oral care procedures with children with autism who exhibit noncompliance can be challenging for oral care professionals. Previous research has elucidated a number of effective behavior analytic procedures for increasing compliance, but some procedures are likely to be too time consuming and expensive for community-based oral care providers to adopt. The purpose of this study was to use Behavioral Skills Training to teach dental hygiene students and staff to implement basic function-based behavior analytic strategies to reduce noncompliance and increase their success in performing oral care exams and cleanings in vivo. All participants rapidly acquired the techniques and used them effectively during exams and cleanings following BST, and skills generalized to their completion of an X-ray procedure with several children with autism. The number of steps attempted in all procedures increased relative to baseline for all participants.  相似文献   
103.
We report on an aneuploidy syndrome due to the unbalanced segregation of a familial translocation (4;21)(p16.3;q22.1) causing a partial 4p monosomy and a partial 21q trisomy. The three affected children presented with severe failure to thrive, short stature, microcephaly, profound hypotonia, and mental retardation. The face, very similar in the three children, is characterized by frontal bossing, upslanting of the palpebral fissures, short nose, and deep set ears, giving the overall appearance of the Down syndrome. The molecular study has defined the aneuploid segment on both 4p and 21q. Most of the Down syndrome critical region was found to be trisomic, while only part of the candidate Wolf-Hirschhorn syndrome critical region was deleted, suggesting that this region is not critical for the major malformations characteristic for WHS. © 1996 Wiley-Liss, Inc.  相似文献   
104.
The aim of this report was to evaluate the effectiveness of the endoscopic treatment of colonic polyps to allow secondary prophylaxis in order to prevent the onset of cancer arising from adenomas. From October 2002 to January 2004 we performed 487 colonoscopies on a patient group with the following indications: screening prior to kidney transplant; screening for colorectal cancer (patients positive at faecal occult blood testing); follow-up of patients who had undergone colonic resections for colorectal cancer; patients with other diseases. Colorectal polyps were diagnosed in 15 males and 15 females, with a mean age of 63 years. All the neoplasms were resected during colonoscopy and specimens sent for histological study. The histological examinations yielded the following results: 4 hyperplastic polyps; 9 tubular adenomas (6 with mild, 2 with mild-to-moderate, and 1 with severe dysplasia); 8 tubulo-villous adenomas (3 with mild, 1 with mild-to-moderate, and 4 with moderate dysplasia); 4 villous adenomas (3 with mild and 1 with severe dysplasia); 1 adenocarcinoma; 1 inflammatory polyp; in 3 cases we were unable to retrieve the polyps after polypectomy. Colonoscopic detection of a neoplasm allows us to remove it and send to the pathology laboratory for definitive histological diagnosis. Moreover, snare polypectomy can be a radical treatment for dysplastic polyps without stromal axis and basal membrane infiltration. We therefore conclude that colonoscopy allows not only early diagnosis of colonic neoplasms, but also radical curative treatment in the early stages.  相似文献   
105.
106.
The human colon is still a relatively unknown viscus, especially concerning its motor activity. However, in recent years, techniques have been perfected that allow a better understanding of colonic motility, especially through prolonged recording periods. In this way, it has been demonstrated that the viscus contracts according to a circadian trend, is responsive to physiological stimuli (meals, sleep), and features high amplitude, propulsive contractions that are part of the complex dynamic of the defecatory process. These physiological properties and their alterations in patients with chronic idiopathic constipation are reviewed in this article.  相似文献   
107.
The aim of this study was to analyze the incidence of ureteral stenosis in a life-supporting human decay-accelerating factor (hDAF) transgenic pig-to-cynomolgus monkey kidney transplantation model and determine the role of possible immunological events in its pathogenesis. Thirty consecutive bi-nephrectomized cynomolgus monkeys received a kidney from hDAF transgenic pigs with or without a ureteral stent. Four monkeys were euthanized prematurely after transplantation. In the remaining 26 cases, the mean survival was 24 +/- 19 days. Except in one case, there was a close relationship between ureter and kidney in terms of type and severity of rejection. There were six ureteral stenoses; five were repaired by stent positioning and resurgery extended survival for an additional 16 +/- 10 days. The stenotic ureters showed diffuse acute humoral xenograft rejection (AHXR), while all cases with no or only focal signs of ureteral rejection never revealed ureteral obstruction. Use of a ureteral stent extends the survival of a xenografted primate, thereby helping to clarify the immunological events surrounding the onset of AHXR in kidneys in long-term xenograft recipients.  相似文献   
108.
Phenotypic characterization of DYT13 primary torsion dystonia.   总被引:3,自引:0,他引:3  
We describe the phenotype of DYT13 primary torsion dystonia (PTD) in a family first examined in 1994. A complete neurological evaluation was performed on all available family members: 8 individuals were definitely affected by dystonia. The family was re-evaluated in March 2000: at that time, 3 more individuals had developed symptoms of dystonia. Inheritance of PTD was autosomal dominant, with affected individuals spanning three consecutive generations and male-to-male transmission. Age at onset ranged from 5 to 43 years. Onset occurred either in the craniocervical region or in upper limbs. Progression was mild, and the disease course was benign in most affected individuals; generalization occurred only in 2 cases. We did not find anticipation of age at onset or of disease severity through generations. Most subjects presented with jerky, myoclonic-like dystonic movements of the neck or shoulders. DYT13-PTD is an autosomal dominant disease, with incomplete penetrance (58%). Clinical presentation and age at onset were more variable than in DYT1-PTD, and the neck was involved in most of those affected. Moreover, the individuals with generalised dystonia were not severely disabled and were able to lead independent lives. To date, this is the only family with DYT13-PTD.  相似文献   
109.
The oral-facial-digital syndromes (OFDS) result from the pleiotropic effect of a morphogenetic impairment affecting almost invariably the mouth, face and digits. Other organ systems can be involved, defining specific types of OFDS. To date, 13 types have been distinguished based on characteristic clinical manifestations. An updated list of these types is provided and recent molecular data are discussed.  相似文献   
110.
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