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21.
We employ diffuse optical tomography (DOT) to track treatment progress in a female subject presenting with locally advanced invasive carcinoma of the breast during neoadjuvant chemotherapy. Three-dimensional images of total hemoglobin concentration and scattering identified the tumor. Our measurements reveal tumor shrinkage during the course of chemotherapy, in reasonable agreement with magnetic resonance images of the same subject. A decrease in total hemoglobin concentration contrast between tumor and normal tissue was also observed over time. The results demonstrate the potential of DOT for measuring physiological parameters of breast lesions during chemotherapy.  相似文献   
22.
Although Levamisole, an antihelmintic drug, has shown to have some modulatory effect on the immune response in clinical trials and experimental models, its mode of action remains obscure. In a group of fifteen patients with rheumatoid arthritis and ankylosing spondylitis receiving Levamisole on an intermittant regime, simultaneous determinations of the lymphocyte subpopulations were made prior to Levamisole administration and 3 months thereafter. No significant changes were observed either in the absolute or in the relative number of T- and B-cell populations, while a statistically significant reduction was found in the "null" cells. These findings suggest that the immune potentiating effect of Levamisole may at least partially be due to a maturation process of the "null" cells.  相似文献   
23.
In a number of pathogens, heat shock proteins (hsp) stimulate humoral and cellular immune responses despite significant sequence identity with host hsp. The 70-kD hsp of Mycobacterium leprae, which shares 47% identity with human hsp70 at the protein level, elicited a T cell response in most Myco. bovis (bacille Calmette-Guérin (BCG)) vaccinees as well as leprosy and tuberculosis patients and their contacts. In order to locate T cell epitopes, DNA fragments encoding portions of the 70-kD hsp were expressed in the vector pGEX-2T and tested for T cell reactivity in an in vitro proliferative assay. Cultures of peripheral blood mononuclear cells (PBMC) from BCG vaccinees indicated that the C-terminal half of the molecule contained multiple T cell epitopes, as the T cells from a majority of Myco. leprae hsp70-reactive individuals responded to C-344. Lower proportions of patients with paucibacillary leprosy (36%) and tuberculosis patients (16%) responded to C-344. The smaller C-142 fragment which includes the terminal 70 residues unique to Myco. leprae and is the target for the human antibody response elicited a cellular response in few patients and no vaccinees. In order to map T cell epitopes, two series of synthetic peptides encompassing the region 278-502 were prepared. Using overlapping 12mer and 20mer peptides, this region of the molecule was found to contain several potential T cell epitopes. The longer peptides gave a clearer indication of reactive sequences including regions of the molecule which were not identified with the 12mer peptides. Fine mapping of reactive peptide pools using the 12mer peptides identified two T cell epitopes. Although both were located in regions of the molecule shared with Myco. tuberculosis, one appeared to be cross-reactive with the equivalent human sequence, and thus has the potential to initiate autoimmune responses.  相似文献   
24.
Previous analysis of porcine respiratory coronavirus (PRCV) mRNA species showed that mRNAs 2 and 3 were smaller than the corresponding transmissible gastroenteritis virus (TGEV) mRNA species (Page et al. (1991) J. Gen. Virol. 72, 579-587). Sequence analysis showed that mRNA 3 was smaller due to the presence of a new putative RNA-leader binding site upstream of the PRCV ORF-3 gene. However, this observation did not explain the deletion observed in PRCV mRNA 2. Polymerase chain reaction (PCR) was used to generate cDNA from the 3' coding region of the putative polymerase gene to the poly (A) tail of PRCV for comparison to the equivalent region from TGEV. The PRCV S protein was found to consist of 1225 amino acids, which had 98% similarity to the TGEV S protein. However, the PRCV S gene contained a 672 nucleotide deletion, corresponding to 224 amino acids (residues 21 to 245 in TGEV S protein), 59 nucleotides downstream of the S gene initiation codon. The PRCV genome from the ORF-3 gene to the poly (A) tail was sequenced for comparison to TGEV in order to identify other potential differences between the two viruses. Four ORFs were identified that showed 98% similarity to the TGEV ORF-4, M, N and ORF-7 genes. No other deletions or any PRCV specific sequences were identified.  相似文献   
25.
26.
The bioavailability, biochemical effects, and safety of a slow-release preparation of sodium fluoride were examined. In 8 normal volunteers, a single administration of slow-release sodium fluoride (25 mg) caused a slow rise and gradual decline in serum fluoride concentration, thus avoiding sharp peaks produced by a rapid-release preparation. In 37 patients with postmenopausal osteoporosis, serum fluoride concentration was kept within the "therapeutic window" (95-100 ng/ml) during long-term intermittent sodium fluoride (slow-release) therapy (25 mg twice/day, given for 3 months in each 5-month cycle over five cycles). Serum fluoride was also kept within the therapeutic window in 64 patients who took sodium fluoride (slow release) continuously over 12 months. Serum osteocalcin concentration increased progressively during fluoride treatment (correlation coefficient of 0.88, p less than .001 for the relationship between serum osteocalcin and duration of therapy). Side effects to slow-release sodium fluoride therapy, assessed in 101 patients at two study sites, were minor and included diarrhea in 2 patients, nausea in 2 patients, abdominal pain and cramping in 2 patients, foot pain in 2 patients, and joint pain in 6 patients. Thus, slow-release sodium fluoride confers desired level of fluoride in serum, while providing safety of usage.  相似文献   
27.
BackgroundBacillus Calmette–Guérin (BCG) vaccine provides partial protection against Buruli ulcer caused by Mycobacterium ulcerans in epidemiological studies. This study aimed to quantify M. ulcerans-specific immune responses induced by BCG immunisation.MethodsIntracellular cytokine analysis of in-vitro experiments done 10 weeks after BCG immunisation in 130 Australian infants randomised to one of three BCG vaccine strains given either at birth (BCG-Denmark, BCG-Japan, or BCG-Russia) or at two months of age (BCG-Denmark).ResultsProportions of polyfunctional CD4+ T-cells were higher in M. ulcerans-stimulated compared to unstimulated control samples. These proportions were not influenced by the vaccine strain or timing of the immunisation. The M. ulcerans-specific immune responses showed similar patterns to those observed in M. tuberculosis-stimulated samples, although they were of lower magnitude.ConclusionsOur data show that BCG immunisation induces M. ulcerans-specific immune responses in infants, likely explaining the cross-protective effect observed in epidemiological studies. (ACTRN12608000227392)  相似文献   
28.
Using the cDNA for rat liver mitochondrial carnitine palmitoyltransferase I (CPT I; EC 2.3.1.21) as a probe, we isolated its counterpart as three overlapping clones from a human liver cDNA library. Both the nucleotide sequence of the human cDNA and the predicted primary structure of the protein (773 aa) proved to be very similar to those of the rat enzyme (82% and 88% identity, respectively). The CPT I mRNA size was also found to be the same (approximately 4.7 kb) in both species. Screening of a human genomic library with the newly obtained cDNA yielded a positive clone of approximately 6.5 kb which, upon partial analysis, was found to contain at least two complete exons linked by a 2.3-kb intron. Oligonucleotide primers specific to upstream and downstream regions of one of the exon/intron junctions were tested in PCRs with DNA from a panel of somatic cell hybrids, each containing a single human chromosome. The results allowed unambiguous assignment of the human liver CPT I gene to the q (long) arm of chromosome 11. Additional experiments established that liver and fibroblasts express the same isoform of mitochondrial CPT I, legitimizing the use of fibroblast assays in the differential diagnosis of the "muscle" and "hepatic" forms of CPT deficiency. The data provide insights into the structure of a human CPT I isoform and its corresponding gene and establish unequivocally that CPT I and CPT II are distinct gene products. Availability of the human CPT I cDNA should open the way to an understanding of the genetic basis of inherited CPT I deficiency syndromes, how the liver CPT I gene is regulated, and which tissues other than liver express this particular variant of the enzyme.  相似文献   
29.
Schwannomas of the eighth cranial nerve are rare in children. We report a 4 10/12 - year-old girl with no evidence of neurofibromatosis who presented with facial droop. Radiographic studies revealed a large cerebellopontine angle tumor. At surgery, the tumor was attached to the eighth cranial nerve and histologically was a schwannoma. This is the youngest reported case of unilateral eighth cranial nerve schwannoma in a patient without the stigmata of neurofibromatosis.  相似文献   
30.
Joint meetings between the members of the US Family Planning Services Program and the STD Program of Region X (comprising Alaska, Idaho, Oregon, and Washington) from fall 1986 through spring 1987 led to the screening and treatment of patients with chlamydia. Samples from patients were sent to state health department laboratories in Idaho, Washington, and Oregon. A direct fluorescent antibody (DFA) slide technique was used to process the cervical smears. Clinic visit record (CVR) information and laboratory results were collected by a central data management company, and sent to CDC and Region X researchers. 6 clinics in 3 of the states collected 2 cervical samples from each of 3000 patients, 1 for smear (DFA slide) and 1 for tissue culture over a 4-month period. During the 1988-1990 period, 136 clinics in the region supplied patient information and test results on over 300,000 samples. Overall, positive rates for chlamydia in the region went from a high of 10.9% in the 1st quarter of 1988 to 6.8% in the last quarter of 1990, with an overall declining trend. This amounted to an almost 37% decrease within the region. When analyzed by state, the positivity rates and decreases were relatively similar: Alaska, 12.2% to 10.0% positivity (18% decrease); Idaho, 10.5% to 8.0% (24% decrease); Oregon, 8.9% to 6.9% (22% decrease); and Washington, 9.3% to 6.6% (29% decrease). In patients 17 years of age and younger, positive rates for chlamydia fell 19%, from 12.2% in 1988 to 9.9% in 1990. In women 18-19 years old and women 20-24 years old, the rates fell 24% and 31%, respectively. Larger decreases in chlamydia rates were found among women in the 25-29 year age group (31% reduction) and in those 30 years old and older (44% reduction). Infection rates decreased in all race/ethnic groups, except Asians. Approximately 2/3 of the women with positive chlamydia tests had no apparent symptoms of disease. Conversely, the presence of certain clinical indicators seemed to correlate with the probability of a positive test result.  相似文献   
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