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1.
Infantile glaucoma in Down's syndrome (trisomy 21)   总被引:2,自引:0,他引:2  
We examined five patients with Down's syndrome and bilateral infantile glaucoma. In the first few months of life four patients had large cloudy corneas, breaks in Descemet's membrane, increased intraocular pressure, photophobia, and tearing. In one patient the diagnosis was delayed until 3 1/2 years of age because of concomitant nasolacrimal duct obstruction. Two patients developed cataracts and retinal detachment and have undergone multiple surgical procedures. The clinical course in these two older patients suggests that coexistence of congenital glaucoma, severe myopia, and cataracts in patients with trisomy 21 strongly predisposes for the development of retinal detachment and poor visual outcome.  相似文献   
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Propofol, administered intravenously for induction and as a continuous maintenance anaesthetic with nitrous oxide, was compared, in a group of elderly patients scheduled for ophthalmic surgery, with an anaesthetic technique (etomidate, alfentanil, nitrous oxide and isoflurane) specifically chosen to be haemodynamically stable and evanescent in action. Both techniques resulted in similar effects on blood pressure after induction, intubation and surgical incision, but propofol did not prevent increases in heart rate as effectively at these times. Furthermore, during maintenance anaesthesia, cardiovascular stability and anaesthetic depth were more easily achieved in the group where etomidate, alfentanil and isoflurane were used. Propofol decreased intra-ocular pressure after intubation, while in both groups recovery was rapid with no significant complications. A subgroup of patients receiving alpha-methyldopa had significantly longer post-anaesthetic recovery times.  相似文献   
4.
A new syndrome of congenital cataract, hearing loss, hypercholesterolemia, spasticity of the lower extremities, and perhaps mental retardation, is described. Manifestation in two brothers with no other affected family members suggests an autosomal recessive pattern of inheritance. A discussion of the differential diagnosis of oculo-auditory syndromes is presented.  相似文献   
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Comparison of two ELISAs for the determination of Hsp70 in serum   总被引:2,自引:0,他引:2  
We have compared a previously developed in-house Sandwich-ELISA with a commercial kit for the determination of heat shock protein (Hsp) 70 in serum. Samples from 64 participants were tested and there was a significant correlation between results obtained using the two assays (r = 0.807, p < 0.0001). Additionally, when ranking samples on a categorical scale, the agreement was good (72%). In the commercial test system Hsp70 was detectable in 42 (66%) of the sera, compared with 61 (95%) in the in-house ELISA method. The three samples with undetectable levels of Hsp70 in the in-house ELISA were among the 22 samples with undetectable levels of Hsp70 in the commercial ELISA kit. The apparent serum concentrations detected were different in the two systems. This dissimilarity can be ascribed to differences in the matrix used. We conclude that the in-house ELISA is more economical and performs well when measuring physiologically high, as well as low, concentrations of Hsp70.  相似文献   
7.
Intestinal mucosal damage in the inflammatory bowel diseases (IBD) Crohn's disease (CD) and ulcerative colitis (UC) involves reactive oxygen metabolites (ROMs). ROMs are neutralized by endogenous antioxidant enzymes in a carefully balanced two-step pathway. Superoxide dismutases (SODs) convert superoxide anion to hydrogen peroxide (H(2)O(2)), which is subsequently neutralized to water by catalase (CAT) or glutathione peroxidase (GPO). Remarkably changed expression levels of the three isoforms of SOD in paired non-inflamed and inflamed mucosae from CD and UC patients have been previously reported in comparison to normal control mucosa. Most notable was the strong up-regulation of Mn-SOD in inflamed epithelium. It was hypothesized that in order to provide optimal protection against ROM-mediated damage, these changes should be coordinately counterbalanced by an increased H(2)O(2)-neutralizing capacity. Therefore, the same tissue samples were used to assess the levels, activities, and/or localization of the most prominent mucosal H(2)O(2)-related antioxidants CAT, GPO, glutathione (GSH), myeloperoxidase (MPO), and metallothionein (MT). Quantitative measurements showed that in both CD and UC patients, intestinal inflammation was associated with increased activities of CAT, GPO, and MPO, whereas the mucosal GSH content was unaffected and the concentration of MT was decreased. Despite this overall increase in mucosal H(2)O(2)-metabolizing enzyme capacity, immunohistochemical analysis revealed a differentially disturbed antioxidant balance in IBD epithelium and lamina propria. In the lamina propria, the risk of direct H(2)O(2)-mediated damage seemed to be restrained by the increasing numbers of CAT- and MPO-positive monocytes/macrophages and neutrophils that infiltrated the inflamed areas. On the other hand, MPO overexpression might increase the lamina propria levels of hypochlorous acid, a stable ROM with multiple pro-inflammatory effects. In the epithelium, the number of cells that expressed CAT remained unchanged during inflammation and GPO was found in only a very low and constant number of epithelial cells. In addition, the inflamed epithelium displayed decreased expression of the hydroxyl radical (OH(*)) scavenger MT. In view of the high epithelial SOD levels in inflamed IBD epithelium, it is speculated that the efficient removal of excess H(2)O(2) is hampered in these cells, thereby increasing not only the risk of detrimental effects of H(2)O(2) directly, but also those of its extremely reactive derivatives such as OH(*). Taken together, the results suggest an imbalanced and inefficient endogenous antioxidant response in the intestinal mucosa of IBD patients, which may contribute to both the pathogenesis and the perpetuation of the inflammatory processes.  相似文献   
8.
The authors report their experience based on a homogeneous series of 70 fractures of the orbital floor. Different anatomo-clinical forms were defined in particular fractures of the orbital floor, accompanying an "internal pivoting" of the cheek bone, which by their incarceration mechanism resemble the trap-door fractures. The blow-out fracture associated with the lower orbital margin also raises therapeutic problems. After a clinical and CT study, the authors recommend treatment via the lower orbital approach using silastic implants. The different sequelae are described clinically and are appraised medically and legally.  相似文献   
9.
The institution of cardiopulmonary bypass during cardiac surgery has profound effects on the plasma concentration of drugs and thus their therapeutic effectiveness. These changes occur through acute hemodilution, altered plasma protein binding, hypotension, as well as the use of hypothermia and heparin administration. Isolation of the lungs from the circulation and the possible sequestration of drugs in the bypass circuit also affect drug plasma concentrations on bypass. The individual characteristics of the drug in question are also important in determining the final plasma concentration: Lipid soluble drugs with a high volume of distribution may be more readily taken up by bypass equipment, but the initial fall in concentration at the start of cardiopulmonary bypass may be more readily counteracted by back diffusion into plasma, if large tissue stores have accumulated. The extent of the drug's plasma protein binding is of importance as the effective free fraction in plasma for highly bound drugs will be sensitive to changes in plasma protein binding brought on by factors such as hemodilution, heparin administration as well as alpha, acid-glycoprotein binding. Clearly the fate of drugs administered before or on bypass is complex and can only be accurately determined by specific studies evaluating drug plasma concentrations. This review updates the available data on anesthetics and drugs used during cardiac surgery in order that anesthetists may predict better the likely effect of drugs administered before or during cardiopulmonary bypass.  相似文献   
10.
BACKGROUND: It is generally accepted that Alzheimer's disease (AD) is mainly characterized by memory disorders. Although recent studies also point to an important role of attention deficits early in the disease, this notion has not yet emerged in clinical practice. Our aim was to assess whether attention, quantified by reaction times, can discriminate between patients with mild AD and controls and therefore contribute to clinical diagnosis. METHODS: In a cross-sectional study, 33 patients with mild AD were matched with cognitively healthy elderly controls for age, gender, educational level and depressive mood. Selective attention (SA), alternating attention (AA) and error-rates were measured by a modified reaction time test. RESULTS: Significant differences between both groups were found for all measures. Logistic regression showed that SA (corrected for individual processing speed) and error-rates could correctly classify subjects with an overall hit ratio of 81%. When attention measures were not corrected for individual processing speed, the overall hit ratio improved to 97%. CONCLUSION: SA and AA deteriorate in patients with mild AD and these measures can be used to discriminate between patients and matched controls, independently of depressive mood.  相似文献   
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