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981.
The pulsed tunable dye laser (PTDL) is generally considered to have a very low incidence of adverse effects, allowing it to become the treatment of choice for the majority of port wine stains (PWS). The low incidence of adverse effects has led to difficulties in determining the true incidence and type of adverse effect seen with this laser. We therefore undertook a retrospective study of 701 patients with PWS, who received 3877 full treatments to determine the incidence and type of adverse effects seen following treatment with the PTDL. Blistering and crusting were seen in 5·9% and 0·7% of patients, respectively, but were transient events which usually healed without permanent sequelae. Hyperpigmentation was the most frequently observed adverse effect seen in 9·1% of patients but generally showed gradual resolution over 6–12 months. Hypopigmentation was infrequent, seen in 1.4% of patients. The most significant adverse effects were atrophic and hypertrophic scarring seen in 4·3% and 0·7% of patients, respectively. Our observations show that there is a small but definite risk of atrophic scarring with a predisposition for younger patients. Hypertrophic scarring can occur albeit rarely and there may be a predisposition towards the neck. In most cases test areas were not predictive of scarring. This underlines the need for a full discussion of scarring risk in patients with PWS undergoing treatment with the PTDL.  相似文献   
982.
983.
Ultraviolet radiation B (UVB) on the skin induces erythema, inflammation and modifications of the immune system. These changes have been reported after excessive short-term or long-term exposure to broad spectrum UVB. In this study, we examined the effects of local repetitive UVB irradiation of 311 nm wavelength on the skin of seven young volunteers. Skin biopsies were taken before and after UVB irradiation, and we immunohistochemically analyzed the expression of CD1a and HLA-DR antigens of Langerhans cells (LC), the possible infiltration of dermis/epidermis by CD11b macrophages, the modifications or the induction of intercellular adhesion molecule-1 (ICAM-1), E-selectin and vascular cell adhesion molecule-1 (VCAM-1) involved in the binding of leukocytes to the endothelial surface and the development of perivascular infiltrates of LFA-1+ mononuclear cells. We also determined the expression of substance P receptors (SPR) using biotinylated substance P (SPB). Exposure of UVB 311 nm induced a drastic reduction of CD1a+ cells and a moderate increase of HLA-DR+ dendritic cells in the epidermis without infiltration by CD11b macrophages. An increase of the binding of SPB to upper layer epidermal cells was noted in five of seven biopsies. In the dermis, vessel-associated ICAM-1 expression increased and an induction of E-selectin occurred on nearly 20 to 40% of endothelial cells, but VCAM-1 expression remained undetectable. The percentage of LFA-1+ cells did not change significantly after irradiation. These observations may be compatible with a selective role of UVB 311 nm on the skin immune response.  相似文献   
984.
The objective of this article is to describe various radiographic projections which can be used during endodontic therapy. Changes to the angulation of the X-ray beam in relation to the teeth and film can help diagnosis and treatment by producing images which provide additional information not always visible on radiographs taken with standard angulations. For example, changes in angulation can be useful to determine the number and curvature of roots and canals, to identify superimposed roots and to distinguish between anatomical landmarks and apical pathology. Although use of such techniques increases the diagnostic yield of films, it must be appreciated that such views lead to images that are less distinct because of inherent image distortion. Nevertheless, use of the various techniques during endodontics can provide substantial benefit for clinicians in their daily practice.  相似文献   
985.
Mutations P225L and P225R were identified in codon 225 of the gene for ornithine transcarbamylase (OTC) in two patients with the neonatal form of OTC deficiency. The mutations occur at a CpG dinucleotide and eliminate a unique MspI restriction site in exon 7 of the OTC gene. They do not alter existing splice sites or create new sites, as judged from the nucleotide sequence. Both mutations are associated with undetectable levels of OTC antigen in liver homogenates, and with either complete lack of OTC activity (P225R mutation) or very small residual activity (0.15% of normal in the P225L mutation). The residual activity observed with P225L exhibits normal pH dependence, little or no increases in the Km values for ornithine and carbamoyl phosphate and normal stability at either 37°C or, in the presence of 0.66 mol/L urea, at 0°C. The latter conditions were used to examine whether the P225L mutation favours dissociation of the active OTC trimer. Given the normal stability and lack of tendency to dissociation of the mutant enzyme, it appears likely that the dramatic reduction in the level of OTC protein is due to inefficient conversion of the mutant OTC precursor polypeptide (pOTC) into the correctly localized, appropriately folded, mature enzyme trimer, suggesting degradation of pOTC in transit to the mitochondria.  相似文献   
986.
Congenital intermaxillary fusion is a rare anomaly. Combination of the anomaly with any type of facial cleft is extremely rare. Death in a majority of these patients as a result of feeding and aspiration problems in early life may have caused the reports to be limited. In this article a 5-year-old patient, probably the first in the literature having Tessier type VI-VII facial cleft combination associated with bimaxillary fusion and anophthalmia on the right side, is presented. The patient has survived on fluid meal through a very small opening for 5 years. The features of the case are presented, and the time and method of the management of such a rare anomaly are discussed with a review of the literature.  相似文献   
987.
Efficient fragmentation is the most important prerequisite for successful treatment of gallstones by extracorporeally induced shock waves. No data are available on the amount of energy necessary for stone disintegration and on the threshold energy below which no further fragmentation occurs. We therefore performed an in vitro investigation on human cholesterol gallstones to elucidate physical laws governing shock-wave lithotripsy. First, the focal pressure of the lithotripter was measured to calculate the energy traversing a stone. Second, 96 gallstones from 16 gall bladders were analysed with respect to physicochemical composition, radiological features and ultrasound before fragmentation was performed. Energy for stone disintegration was constant within each stone family but varied between 4.6 J mL?1 and 36.8 J mL?1 in different families. This energy correlated linearly with stone volume. None of the radiological and physicochemical factors revealed a clear-cut correlation of the different energies necessary for similar stone disintegration. The threshold energy differed between 0.26 mJ and 1.04 mJ per pulse. In conclusion, stone volume was the best parameter predicting stone fragmentation. However, in cholesterol stones with a similar composition the required energy per volume varies considerably together with the threshold energy. Radiological and ultrasound parameters appear to be of minor importance in explaining these differences.  相似文献   
988.
B Moum  A Ekbom  M H Vatn  E Aadland  J Sauar  I Lygren  T Schulz  N Stray    O Fausa 《Gut》1997,40(3):328-332
BACKGROUND: The incidence figures for ulcerative colitis (UC) and Crohn's disease (CD) have been difficult to interpret, and geographical variations may be due to differences in classification criteria and study design. Few studies have based the incidence on prospective systematic follow up to confirm the initial diagnosis. METHODS: Between 1990 and 1993, in a prospective incidence study of inflammatory bowel disease (IBD) in south eastern Norway, 527 cases of UC, 228 cases of CD, 36 cases of indeterminate colitis (IND), and 55 cases of possible IBD were identified, yielding an annual incidence of 13.6, 5.9, 0.9, and 1.4 per 10(5) respectively. The diagnosis and all clinical data were reviewed by two gastroenterologists independently of each other. One to two years after diagnosis, all patients were offered a clinical follow up in which the initial diagnosis was assessed. RESULTS: Between the time of diagnosis and the follow up, 16 patients had died, four of complications related to IBD. Of the remaining 830 patients, 98% (814/830) were available for follow up, 93% (772/830) attended a clinical examination which included a colonoscopy in 77% (637/830), and the remainder had had a telephone interview, or reassessment based on hospital records, or both. Twenty seven patients were reclassified as not having IBD (3%), and 65 patients were characterised as possible IBD (8%). Of the patients initially classified as UC, 88% had their diagnosis confirmed, compared with 91% with an initial diagnosis of CD. In patients with indeterminate colitis, 33% were classified as definite UC and 17% as CD. This reclassification of patients yielded a corrected annual incidence of 12.8 for UC and 6.0 for CD. CONCLUSION: At follow up one to two years after the diagnosis of IBD, the initial incidence was only marginally altered. This is probably due to uniform inclusion criteria and careful diagnostic methods. The study also illustrates the importance of the re-evaluation of the initial diagnosis as close to 10%, both among patients with UC and CD, were reclassified at follow up.  相似文献   
989.
990.
An indirect immunofluorescence assay for the detection of human antibodies to the agent of human granulocytic ehrlichiosis (HGE) was developed and standardized. Antigen was prepared from a human promyelocytic leukemia cell line (HL-60) infected with a tick-derived isolate of the HGE agent (USG3). Suitable antigen presentation and preservation of cellular morphology were obtained when infected cells were applied and cultured on the slide, excess medium was removed, and cells were fixed with acetone. Use of a buffer containing bovine serum albumin and goat serum reduced background fluorescence, and use of an immunoglobulin G (gamma-specific) conjugate reduced nonspecific binding. The assay readily detected specific antibody from HGE patients and did not detect antibody from healthy individuals. No significant reactivity was noted in sera from patients with high titers of antibodies to other rickettsial species. We were able to identify antibodies reactive to USG3 antigen in samples from areas where HGE is endemic that had tested negative to other rickettsial agents. Animal sera reactive against Ehrlichia equi or Ehrlichia phagocytophila bound to the HGE antigen, indicating that the assay may be useful for veterinary use. Comparability between two different laboratories was assessed by using coded human sera exchanged between laboratories. Results from the two laboratories were similar, indicating that the assay can be easily integrated into use for routine testing for HGE. The assay was then compared to an assay using horse neutrophils infected with ehrlichiae. The two assays gave comparable results, indicating that the cell culture-derived antigen can be used for testing samples that have been previously tested with E. equi as an antigen. The new assay offers several advantages over other immunofluorescence methods that use animal-derived antigen and is suitable for use in testing for human antibodies to the HGE agent.  相似文献   
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