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71.
Conjugated catecholamines in human plasma: where are they coming from?   总被引:2,自引:0,他引:2  
The origins of conjugated catecholamines remain poorly known. The aim of the present study was to see whether a major contribution comes from the sympathetic nervous system. We have assumed some kind of parallelism between the activity of the sympathetic nervous system, the amount of catecholamines released and taken up, and the amount of conjugated catecholamines circulating in plasma. Accordingly, an increase in sympathetic activity should be followed by an increase in the plasma level of conjugated catecholamines. The plasma levels of sulfoconjugated and glucuroconjugated catecholamines were measured in 10 patients with mental disease resistant to drug treatment, before and after electroconvulsive therapy. As expected, blood pressure, norepinephrine concentration, and epinephrine concentration in plasma were transiently increased. Neither sulfoconjugated nor glucuroconjugated catecholamines were significantly changed. Conjugated catecholamines were measured in 10 volunteers before and at the nadir of insulin-induced hypoglycemia. As expected, plasma levels of norepinephrine and epinephrine were drastically increased. Plasma levels of sulfoconjugates were decreased and glucuroconjugates increased; these were narrow but statistically significant variations. Data reported in the present article do not support a major role for the activity of the sympathetic system in fixing the level of conjugated catecholamines in human plasma. This is a negative, but nonetheless important, observation. In human subjects, currently available information suggests an important role for the intestinal wall and renal function in determining the level of circulating sulfoconjugates.  相似文献   
72.
AIMS: To confirm the validity of the method of diagnosing fetal ventriculomegaly at autopsy by measuring cerebral mantle thickness at the frontal lobe and to further evaluate whether taking three measurements at three separate sites is even more reliable. METHODS: The thickness of the cerebral mantle was measured at three sites: the frontal lobe, posterior-frontal lobe and occipital lobe, in 10 human fetuses which were clinically diagnosed by ultrasound to have ventriculomegaly, and in 120 control fetuses. Most fetuses were obtained during the second trimester. The mantle thicknesses were charted against foot length and crown-rump length in each case. RESULTS: Fetal cerebral mantle thickness was reduced in the three sites examined in eight of ten fetuses with a pre-autopsy diagnosis of ventriculomegaly. The mantle thickness was in the normal range in a growth-restricted fetus of 19 weeks gestational age with trisomy 21, mild ventriculomegaly, hydrops and cerebral oedema, when correlated with crown-rump and foot lengths. In a 32-week growth-retarded fetus with a prenatal ultrasound diagnosis of ventriculomegaly, cerebral mantle thickness was also within the normal range relative to crown-rump and foot lengths. CONCLUSION: Measurement at autopsy of cerebral mantle thickness is a reproducible and reliable method of confirming the diagnosis of ventriculomegaly in second trimester fetuses. Fetal cerebral mantle thickness measurement taken at the three sites must be correlated with crown-rump and foot length. In most cases where ventriculomegaly was established, the mantle thickness was reduced in fetuses in all three sites examined. The relative thickness of the cerebral mantle in different areas was often abnormal in the presence of ventriculomegaly. Our study of small numbers of cases also suggested that the method of measurement may not be reliable in some cases where there is only mild ventriculomegaly, cerebral oedema or growth retardation.  相似文献   
73.
BACKGROUND: To determine the efficacy and tolerability of repetitive transcranial magnetic stimulation (rTMS) as a treatment for obsessive compulsive disorder (OCD) in a double-blind placebo-controlled study. METHOD: Subjects with treatment-resistant OCD were randomized to rTMS (n = 10) or sham rTMS (n = 8) for 10 sessions of daily stimulation over the left dorsolateral prefrontal cortex (DLPFC), with subjects and raters being blind to the treatment. Subjects were offered an open extension of up to 20 sessions of rTMS. RESULTS: The two groups did not differ on change in Yale-Brown Obsessive Compulsive Scale (YBOCS) or Maudsley Obsessive-Compulsive Inventory scores over 10 sessions, with or without correction for depression ratings. Over 20 sessions, there was a significant reduction in total YBOCS scores, but not after controlling for depression. rTMS over 20 sessions was well tolerated. CONCLUSION: Two weeks of rTMS over the left DLPFC is ineffective for treatment-resistant OCD.  相似文献   
74.
ABSTRACT: BACKGROUND: Hyperhomocysteinemia as a consequence of the MTHFR 677 C > T variant is associated with cardiovascular disease and stroke. Another factor than can potentially contribute to these disorders is a depleted nitric oxide level, which can be due to the presence of eNOS +894 G > T and eNOS 786 T > C variants that make an individual more susceptible to endothelial dysfunction. A number of genotyping methods have been developed to investigate these variants. However, simultaneous detection methods using polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) analysis are still lacking. In this study, a novel multiplex PCR-RFLP method for the simultaneous detection of MTHFR 677 C > T and eNOS +894 G > T and eNOS 786 T > C variants was developed. A total of 114 healthy Malay subjects were recruited. The MTHFR 677 C > T and eNOS +894 G > T and eNOS 786 T > C variants were genotyped using the novel multiplex PCR-RFLP and confirmed by DNA sequencing as well as snpBLAST. Allele frequencies of MTHFR 677 C > T and eNOS +894 G > T and eNOS 786 T > C were calculated using the Hardy Weinberg equation. METHODS: The 114 healthy volunteers were recruited for this study, and their DNA was extracted. Primer pair was designed using Primer 3 Software version 0.4.0 and validated against the BLAST database. The primer specificity, functionality and annealing temperature were tested using uniplex PCR methods that were later combined into a single multiplex PCR. Restriction Fragment Length Polymorphism (RFLP) was performed in three separate tubes followed by agarose gel electrophoresis. PCR product residual was purified and sent for DNA sequencing. RESULTS: The allele frequencies for MTHFR 677 C > T were 0.89 (C allele) and 0.11 (T allele); for eNOS +894 G > T, the allele frequencies were 0.58 (G allele) and 0.43 (T allele); and for eNOS 786 T > C, the allele frequencies were 0.87 (T allele) and 0.13 (C allele). CONCLUSIONS: Our PCR-RFLP method is a simple, cost-effective and time-saving method. It can be used to successfully genotype subjects for the MTHFR 677 C > T and eNOS +894 G > T and eNOS 786 T > C variants simultaneously with 100 % concordance from DNA sequencing data. This method can be routinely used for rapid investigation of the MTHFR 677 C > T and eNOS +894 G > T and eNOS 786 T > C variants.  相似文献   
75.
Pure polymer films cannot meet the diverse range of controlled release and material properties demanded for the fabrication of medical implants or other devices. Additives are added to modulate and optimize thin films for the desired qualities. To characterize the property trends that depend on additive concentration, an assay was designed which involved casting a single polyester poly(lactic-co-glycolic acid) (PLGA) film that blends a linear gradient of any PLGA-soluble additive desired. Four gradient PLGA films were produced by blending polyethylene glycol or the more hydrophobic polypropylene glycol. The films were made using a custom glass gradient maker in conjunction with a 180 cm film applicator. These films were characterized in terms of thickness, percent additive, total polymer (PLGA+additive), and controlled drug release using drug-like fluorescent molecules such as coumarin 6 (COU) or fluorescein diacetate (FDAc). Material properties of elongation and modulus were also accessed. Linear gradients of additives were readily generated, with phase separation being the limiting factor. Additive concentration had a Pearson's correlation factor (R) of >0.93 with respect to the per cent total release after 30 days for all gradients characterized. Release of COU had a near zero-order release over the same time period, suggesting that coumarin analogs may be suitable for use in PLGA/polyethylene glycol or PLGA/polypropylene glycol matrices, with each having unique material properties while allowing tuneable drug release. The gradient casting method described has considerable potential in offering higher throughput for optimizing film or coating material properties for medical implants or other devices.  相似文献   
76.
77.
Microsatellite stable (MSS), CpG island methylator phenotype (CIMP)‐negative colorectal tumors, the most prevalent molecular subtype of colorectal cancer, are associated with extensive copy number alteration (CNA) events and aneuploidy. We report on the identification of characteristic recurrent CNA (with frequency >25%) events and associated gene expression profiles for a total of 40 paired tumor and adjacent normal colon tissues using genome‐wide microarrays. We observed recurrent CNAs, namely gains at 1q, 7p, 7q, 8p12‐11, 8q, 12p13, 13q, 20p, 20q, Xp, and Xq and losses at 1p36, 1p31, 1p21, 4p15‐12, 4q12‐35, 5q21‐22, 6q26, 8p, 14q, 15q11‐12, 17p, 18p, 18q, 21q21‐22, and 22q. Within these genomic regions we identified 356 genes with significant differential expression (P < 0.0001 and ±1.5‐fold change) in the tumor compared to adjacent normal tissue. Gene ontology and pathway analyses indicated that many of these genes were involved in functional mechanisms that regulate cell cycle, cell death, and metabolism. An amplicon present in >70% of the tumor samples at 20q11‐20q13 contained several cancer‐related genes (AHCY, POFUT1, RPN2, TH1L, and PRPF6) that were upregulated and demonstrated a significant linear correlation (P < 0.05) for gene dosage and gene expression. Copy number loss at 8p, a CNA associated with adenocarcinoma and poor prognosis, was observed in >50% of the tumor samples and demonstrated a significant linear correlation for gene dosage and gene expression for two potential tumor suppressor genes, MTUS1 (8p22) and PPP2CB (8p12). The results from our integration analysis illustrate the complex relationship between genomic alterations and gene expression in colon cancer. © 2013 Wiley Periodicals, Inc.  相似文献   
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80.
Williams-Beuren syndrome (WBS) is caused by a approximately 1.5 million base pair deletion at 7q11.23. A common inversion of the region, WBSinv-1, exists as a polymorphism but was also found in individuals with WBS-like features but no deletion, suggesting it could cause clinical symptoms. We performed a full clinical, developmental and genetic assessment of two previously reported individuals with clinical symptoms and WBSinv-1 but no 7q11.23 deletion. We also examined expression of genes at 7q11.23 in individuals in the general population who have WBSinv-1. We show that individuals with clinical symptoms and WBSinv-1 do not show significant clinical or psychological overlap with individuals with WBS. In addition, a 1.3 Mb duplication of part of the velocardiofacial syndrome region on chromosome 22q11.2 was found in one participant with WBSinv-1 and clinical symptoms. We also demonstrate that individuals with WBSinv-1 show normal expression of genes from the WBS region. These results suggest that WBSinv-1 does not cause clinical symptoms and we advise caution when diagnosing individuals with atypical presentation of rare syndromes. Whole genome analysis may reveal previously unidentified copy number variants that could contribute to syndromic features.  相似文献   
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