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61.
We evaluated a rapid urinary antigen detection kit, Binax Now Streptococcus pneumoniae (Binax Inc., USA), which detects S. pneumoniae antigen in urine by immunochromatographic membrane assay, in 379 patients with presumptive pneumonia (total: 454 urine samples). S. pneumoniae antigen was detected in 64 (34%) of 188 patients. In all 64, pneumonia was diagnosed clinically, and there were 11 intense reactivity cases, 27 intermediate cases, and 26 weak cases. We found only two patients with positive sputum cultures for S. pneumoniae among 26 patients with weak reactivity to urinary antigen. The weak urinary antigen reactivity seems to include a false-positive result for S. pneumoniae pneumonia. There were five patients with negative results in whom S. pneumoniae was isolated (false-negative). We took intense and intermediate reactivity to be positive in order to diagnose pneumococcal pneumonia, and the kit showed a sensitivity of 72% and a specificity of 94% in 379 patients. The urinary antigen kit allowed us to diagnose 80% more patients with pneumococcal pneumonia than the use of conventional bacteriological diagnosis alone. There was no significant difference in the initial clinical characteristics, or in the severity of pneumonia among the three groups, according to the color intensity reached using the kit--weak, intermediate, and intense for the reactivity of urinary antigen. The duration of reactivity with S. pneumoniae urinary antigen did not correlate with the clinical characteristics or the severity of pneumonia. We concluded that S. pneumoniae urinary antigen detection kit is a useful adjunct to culturing for determining the etiology of pneumonia.  相似文献   
62.
Hepatic resection under in situ hypothermic hepatic perfusion   总被引:2,自引:0,他引:2  
BACKGROUND/AIMS: Temporary inflow occlusion of the portal triad has been used frequently in hepatectomy to minimize bleeding. On the other hand, Pringle's maneuver produces ischemic-reperfusion injury especially in patients with underlying liver disease. METHODOLOGY: Thirty-seven cases of hepatic resections were performed with intermittent Pringle's maneuver (IP group; n = 17) and in situ hypothermic perfusion (CP group; n = 20). In the CP group, hepatic inflow was continuously occluded, and 4-degree Centigrade Ringer's lactate was administered by drip during resection. Hepatic outflow occlusion was not performed. RESULTS: All patients tolerated the procedures well. Cold perfusion technique significantly decreased both the times required and the blood loss in hepatectomy (p < 0.05). Serum hyaluronic acid levels gradually increased after the induction of hepatectomy and peaked 10 minutes after reperfusion in the both groups. Thereafter, it decreased and showed a significantly lower level in the CP group until 60 minutes after reperfusion (p < 0.05). Hepaplastin levels remained significantly higher in the CP group one week after operation (p < 0.05). CONCLUSIONS: Using the technique of in situ hypothermic perfusion, we can prolong the ischemic time safely with minimal systemic influence even in cases with underlying liver diseases. This may compare favorably with intermittent Pringle's maneuver in terms of reducing hepatic sinusoidal endothelial cell damage during hepatectomy and reperfusion.  相似文献   
63.
Adrenaline increases the rate of cross-bridge cycling in rat cardiac muscle   总被引:1,自引:0,他引:1  
To characterize the myocardial cross-bridge dynamics in catecholamine-induced positive inotropic state, we studied the effects of adrenaline (6 X 10(-6) M) on the transient central segment length (SL) response to step decrease in tension in rat right ventricular papillary muscle in barium contracture. The time course of this response is thought to reflect the kinetics of actin-myosin interaction. The muscle was released stepwise from the steady contracture tension (Tc) to new steady tension levels (Tr) of varying magnitudes at 22 degrees C. When the tension decrease was less than 0.7 Tc, the SL transient responses comprised, in most cases, four phases. The first phase was a rapid and minute shortening during tension reduction; the second was a slow further shortening; the third, a slow lengthening; and the fourth, an extremely slow shortening toward a new steady length under the new tension. Adrenaline showed almost no effect on Tc and the amplitude of SL transients, but markedly reduced the duration of the second (D2) and third (D3) phases of SL transient regardless of the amplitude of tension reduction. The reduction of duration was 14 +/- 3% in D2 and 26 +/- 5% in D3 at Tr/Tc of 0.84 +/- 0.03 on the average (mean +/- S.D.) in nine preparations. The velocity measured from the quasi-steady SL shortening in the second phase increased with the addition of adrenaline, regardless of the amplitude of tension reduction. The increase in the shortening velocity was 16 +/- 6% (mean +/- S.D., n = 9) at Tr/Tc of 0.18 +/- 0.04. These results suggest that adrenaline increases the rate of cross-bridge cycling in cardiac muscle independent of activation level.  相似文献   
64.
The purpose of this study is to verify objectively the rate of slice omission during paging on picture archiving and communication system (PACS) viewers by recording the images shown on the computer displays of these viewers with a high-speed movie camera. This study was approved by the institutional review board. A sequential number from 1 to 250 was superimposed on each slice of a series of clinical Digital Imaging and Communication in Medicine (DICOM) data. The slices were displayed using several DICOM viewers, including in-house developed freeware and clinical PACS viewers. The freeware viewer and one of the clinical PACS viewers included functions to prevent slice dropping. The series was displayed in stack mode and paged in both automatic and manual paging modes. The display was recorded with a high-speed movie camera and played back at a slow speed to check whether slices were dropped. The paging speeds were also measured. With a paging speed faster than half the refresh rate of the display, some viewers dropped up to 52.4 % of the slices, while other well-designed viewers did not, if used with the correct settings. Slice dropping during paging was objectively confirmed using a high-speed movie camera. To prevent slice dropping, the viewer must be specially designed for the purpose and must be used with the correct settings, or the paging speed must be slower than half of the display refresh rate.  相似文献   
65.
Sleep is regulated in a homeostatic manner. Sleep deprivation increases sleep need, which is compensated mainly by increased EEG δ power during non-rapid eye movement sleep (NREMS) and, to a lesser extent, by increased sleep amount. Although genetic factors determine the constitutive level of sleep need and sleep amount in mice and humans, the molecular entity behind sleep need remains unknown. Recently, we found that a gain-of-function Sleepy (Slp) mutation in the salt-inducible kinase 3 (Sik3) gene, which produces the mutant SIK3(SLP) protein, leads to an increase in NREMS EEG δ power and sleep amount. Since Sik3Slp mice express SIK3(SLP) in various types of cells in the brain as well as multiple peripheral tissues from the embryonic stage, the cell type and developmental stage responsible for the sleep phenotype in Sik3Slp mice remain to be elucidated. Here, we generated two mouse lines, synapsin1CreERT2 and Sik3ex13flox mice, which enable inducible Cre-mediated, conditional expression of SIK3(SLP) in neurons on tamoxifen administration. Administration of tamoxifen to synapsin1CreERT2 mice during late infancy resulted in higher recombination efficiency than administration during adolescence. SIK3(SLP) expression after late infancy increased NREMS and NREMS δ power in male synapsin1CreERT2; Sik3ex13flox/+ mice. The expression of SIK3(SLP) after adolescence led to a higher NREMS δ power without a significant change in NREMS amounts. Thus, neuron-specific expression of SIK3(SLP) after late infancy is sufficient to increase sleep.SIGNIFICANCE STATEMENT The propensity to accumulate sleep need during wakefulness and to dissipate it during sleep underlies the homeostatic regulation of sleep. However, little is known about the developmental stage and cell types involved in determining the homeostatic regulation of sleep. Here, we show that Sik3Slp allele induction in mature neurons in late infancy is sufficient to increase non-rapid eye movement sleep amount and non-rapid eye movement sleep δ power. SIK3 signaling in neurons constitutes an intracellular mechanism to increase sleep.  相似文献   
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67.
In seven patients with insulin-dependent diabetes mellitus (IDDM) and 86 patients with non-insulin-dependent diabetes mellitus (NIDDM), serum anti-DNA antibody was measured by a semiquantitative radioimmunoassay (RIA) method. Prevalence of positive anti-DNA antibody (more than 20 U/mL) was five of seven in IDDM patients, 15 of 36 in NIDDM patients with insulin therapy, and seven of 50 in NIDDM patients without insulin therapy. None of normal subjects or patients with impaired glucose tolerance (IGT) showed positive anti-DNA antibody. The titer of anti-DNA antibody was higher in IDDM patients than in age-matched normal subjects (mean +/- SD; 22.1 +/- 15.3 v 6.5 +/- 2.2 U/mL, P less than .05). In patients with NIDDM, the antibody titer regardless of insulin treatment, was higher than in age-matched subjects with IGT (18.5 +/- 13.1 U/mL in NIDDM patients receiving insulin, 14.8 +/- 8.1 U/mL in NIDDM patients not receiving insulin, and 8.8 +/- 3.9 U/mL in IGT patients [P less than .001] for either of NIDDM groups v IGT). The titer of anti-DNA antibody was positively correlated with the duration of diabetes (r = .413, P less than .001) and with the postprandial blood glucose level (r = .311, P less than .01) in NIDDM patients when all of them were combined and analyzed as a group.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
68.
Endothelin is a potent vasoconstrictor/pressor peptide, which we recently characterized from the conditioned culture medium of porcine aortic endothelial cells. We report here the cloning and partial sequencing of the rat endothelin gene. The nucleotide sequence predicted a 21-residue peptide similar to, but distinct from, porcine endothelin; 15 residues of rat endothelin were identical and 3 residues were substitutions by chemically similar amino acid residues to those in the porcine peptide. Synthetic rat endothelin was then prepared according to its deduced amino acid sequence. This synthetic peptide had (i) potent vasoconstrictor activity in the rat aortic strip and in perfused rat heart and (ii) a characteristically long-lasting in vivo pressor activity by intraaortic bolus injection in the conscious rat.  相似文献   
69.
70.
Background Tissue features to predict the presence or absence of lymph node metastasis (pN) in cases of esophageal squamous cell carcinoma found to contact or penetrate the muscularis mucosae (m3) on endoscopic mucosal resection (EMR) have yet to be clarified in detail. This study was conducted to determine the utility of droplet infiltration (DI) as a candidate. Methods In 27 m3 esophageal squamous cell carcinoma cases who underwent esophagectomy, DI parameters (longitudinal diameter, DIs; number of constituent cells, DIn; distance from the primary focus, DId) for droplet infiltration were examined to allow comparison with vessel permeation (VP) as a predictive factor for lymph node metastasis. Results DIs ≤ 20 μm, DIn ≤ 4, and DId ≥ 200 μm all demonstrated relations with pN (P = 0.001, 0.006, and 0.03, respectively). As predictive factors for lymph node metastasis, DIs ≤ 20 μm and DIn ≤ 4 had sensitivity and likelihood ratios (LR) equal to or higher than VP. Conclusions Tissue features of DI (DIs ≤ 20 μm and DIn ≤ 4) can be applied as predictive factors for lymph node metastasis in m3 esophageal cancers after EMR. This is the English version of a research paper reported in Gastroenterol Endosc 2004;46:2086–94.  相似文献   
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