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61.
Hurricanes Katrina and Rita forced many individuals along the coast of Texas and Louisiana to seek shelter inland. Among the evacuees were residents with special needs and residents of nursing homes and group homes caring for mentally retarded and physically disabled persons. Many nurses volunteered to provide health care for those in need. This article discusses challenges and opportunities that were encountered by nurses volunteering in special-needs shelters. Issues related to human and physical resources, patient care, and confidentiality are discussed including lessons learned. As nurses who cared for evacuees in the shelter, it is hoped some of the lessons learned can be utilized in future disasters.  相似文献   
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Invasion of Human Oral Epithelial Cells by Prevotella intermedia   总被引:1,自引:0,他引:1       下载免费PDF全文
Invasion of oral epithelial cells by pathogenic oral bacteria may represent an important virulence factor in the progression of periodontal disease. Here we report that a clinical isolate of Prevotella intermedia, strain 17, was found to invade a human oral epithelial cell line (KB), whereas P. intermedia 27, another clinical isolate, and P. intermedia 25611, the type strain, were not found to invade the cell line. Invasion was quantified by the recovery of viable bacteria following a standard antibiotic protection assay and observed by electron microscopy. Cytochalasin D, cycloheximide, monodansylcadaverine, and low temperature (4°C) inhibited the internalization of P. intermedia 17. Antibodies raised against P. intermedia type C fimbriae and against whole cells inhibited invasion, but the anti-type-C-fimbria antibody inhibited invasion to a greater extent than the anti-whole-cell antibody. This work provides evidence that at least one strain of P. intermedia can invade an oral epithelial cell line and that the type C fimbriae and a cytoskeletal rearrangement are required for this invasion.  相似文献   
64.
Citalopram binds with high affinity to a specific binding site located on the serotonin (5-HT) transporter in 5-HT neurons. The binding affinity of [3H]citalopram was found to increase with increasing concentration of citalopram. This may be a homotropic positive allosteric effect, thus indicating the presence of an allosteric binding site for citalopram. The molecular weight of the proteins containing the high-affinity binding sites for citalopram and paroxetine, as well as the allosteric binding site for citalopram were determined by the irradiation method. The molecular weights of the three binding site proteins were found to be the same, suggesting that all three binding sites are located on the same protein molecule in the 5-HT transporter. The results support a hypothesis that the binding area for [3H]citalopram is located deeper in the transport channel than the [3H]paroxetine binding area. Thus the two high-affinity binding sites probably cover different, but overlapping, parts of the protein molecule. The allosteric binding site may be located elsewhere on the protein where it induces conformational changes of the 5-HT transporter with the result that high-affinity bound ligands get trapped in the transport channel, thereby explaining the increase in affinity.  相似文献   
65.
Mutations in the C1-inhibitor (C1-INH) gene, leading to low functional levels of C1-inhibitor protein, cause hereditary angioedema (HAE). The disease is characterized by episodic edema in a number of organs. Typically, swellings occur in extremities and face, often accompanied by crampy abdominal pain. Laryngeal edema may lead to suffocation. Type II HAE patients have low functional C1-INH values stemming from only one normal allele. Antigenic C1-INH values, however, are normal or increased owing to the presence of a dysfunctional protein from the mutated allele. The mutations are usually found in exon 8 coding for the amino acids near the reactive centre (P1). Previously, no mutations in the C1-INH gene had been published from the Scandinavian countries. In this work, exon 8 of the C1-inhibitor gene was sequenced in members of two different kindreds, from western and northern Norway, who were suffering from HAE type II. A common point mutation was found within the bait region encoding the reactive centre. The codon CGC was converted to TGC at position 17 970, corresponding to an Arg → Cys replacement which reportedly is the second most frequent type II HAE mutation. This information was utilized to develop a mutation-specific polymerase chain reaction (PCR) for the identification of affected family members. The antisense 17-mer primer (5'-AAGACCAGCAGGGTGCA-3') was successfully applied and AmpliTaq Gold was used in the PCR.  相似文献   
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Abstract. Objectives:To describe the outcomes of a mass carbon monoxide (CO) intoxication, and to calculate the CO half-life in a pediatric school-aged population.
Methods:A retrospective chart review was performed based on Regional Poison Center database information, hospital laboratory data, and medical records of the pediatric patients who sought care at one of 3 St. Louis area hospitals, after exposure to high levels of CO. Exposures occurred on January 5, 1996, after evidence of a CO leak was discovered at an area elementary school. Charts were reviewed for major demographics, symptoms reported, carboxyhemoglobin (COHb) levels and times, and level of effect.
Results:Information about 177 (35%) of the 504 children in attendance at school that day was available. Mean age was 8.7 ± 1.8 years (range 4–12 years). Symptoms were present in 155 (88%) of the 177 children for whom data were available. Initial COHb levels were obtained for 147 (83.1%) of the 177 children. First mean COHb level was 7.0% (95% CI = 6.6–7.5%). Second COHb level was obtained for 26 children with a mean of 2.7% (95% CI = 2.2–3.2%). Calculated half-life of COHb, on 100% 02 at 1 atm, was 44.0 minutes (95% CI = 39.6–48.2 minutes).
Conclusion:Some children had symptoms at COHb levels that traditionally have been considered nontoxic. The elimination of COHb was found to be more rapid in this population of children than reported in other studies.  相似文献   
68.
Estrogen receptor (ER) and progesterone receptor (PR) contents were determined by biochemical (dextran charcoal-coated (DCC) assay) and immunohistochemical (ICA) methods in biopsies from 145 primary endometrial adenocarcinomas and those with eligible receptor measurements were analyzed with respect to correlations to cancer-specific survival in a multivariate analysis including histopathological characteristics. Median patient follow-up time was 67 months with 18 cancer deaths. The PR-DCC and ER-DCC values were dichotomized according to levels previously found by us to correspond to the best agreement between receptor status as determined by the DCC and ICA methods (130 fmol/mg cytosol protein for ER, 114 fmol/mg for PR). Using these thresholds, we found by multivariate analysis that “high” PR-DCC levels (>114 fmol/mg) correlated significantly (P= 0.004) with survival, independent of stage risk group (Ia + b vs Ic-IV). Patient age and histologic grade were prognostic factors in a univariate setting, but these parameters were eliminated in the multivariate model. While the PR-ICA scores also correlated significantly and independently with survival, the predictive effect of PR-ICA positivity alone could not be statistically evaluated due to the number of cases with eligible ICA values. However, we suggest that owing to a close correlation between DCC and ICA results, PR-ICA status may provide significant prognostic information when DCC measurements are not available.  相似文献   
69.
CYP2D6 genotyping was carried out by XbaI restriction fragment length polymorphism analysis and polymerase chain reaction in 168 healthy Danish volunteers, 77 extensive metabolizers (EM) and 91 poor metabolizers (PM) of sparteine. All EM were genotyped correctly as heterozygous or homozygous for the functional (wild type) gene, D6-wt. However, the D6-wt gene was apparently also present in 11 (12%) of the PM who accordingly were incorrectly genotyped as EM. The specificity of genotyping PM thus was 100% but the sensitivity was only 88%. The most common allele was the D6-wt with an apparent frequency of 0.741 (0.026) in the Danish population and the second most common allele was the D6-B with an apparent frequency of 0.194 (0.024). The median (range) of the sparteine metabolic ratio (MR) in 47 homozygous D6-wt EM was 0.28 (0.11–4.10) and the corresponding value in heterozygous EM was 0.36 (0.11–9.10). The median difference was 0.09 (95% confidence interval: 0.02–0.16). CYP2D6 phenotyping is a promising tool in tailoring the individual dose of tricyclic antidepressants, some neuroleplics and some antiarrhythmics. However if the genotype test could be improved with regard to both sensitivity in PM and the ability to predict CYP2D6 activity in EM then it would be of even greater clinical value in therapeutic drug monitoring.  相似文献   
70.
There is little agreement about the methodology of clinical trials of antipsychotic drugs in patients with negative symptoms. A literature review revealed wide variation in experimental design, rating scales and study duration. This reflects differing views as to the definition and response to treatment of negative symptoms. Some degree of standardization would improve comparability of studies and aid the development of new compounds. Patients included in such studies should have displayed negative symptoms for at least 6 months. Depressive symptoms, positive schizophrenic symptoms and extrapyramidal signs may all influence or be confused with negative symptoms and may respond to treatment; they should be at a low level at baseline and should be measured during the study period. Studies should last at least 8 weeks. Several scales are available for measuring negative symptoms and are reviewed; a global impression score should be used additionally.  相似文献   
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