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71.
A comparison of quantitative results expressed in hepatitis C virus (HCV) international units per milliliter, obtained from the VERSANT HCV RNA 3.0 (bDNA-3.0) assay, the QUANTIPLEX HCV RNA 2.0 (bDNA-2.0) assay, and the COBAS AMPLICOR HCV MONITOR version 2.0 (HCM-2.0) test was performed. A total of 168 patient specimens submitted to the Mayo Clinic Molecular Microbiology Laboratory for HCV quantification or HCV genotyping were studied. Of the specimens tested, 97, 88, and 79% yielded quantitative results within the dynamic range of the bDNA-3.0, bDNA-2.0, and HCM-2.0 assays, respectively. Overall, there was substantial agreement between the results generated by all three assays. A total of 15 out of 29 (52%) of the specimens determined to contain viral loads of <31,746 IU/ml by the bDNA-3.0 assay were categorized as containing viral loads within the range of 31,746 to 500,000 IU/ml by the bDNA-2.0 assay. Although substantial agreement was noted between the results generated by the bDNA-2.0 and bDNA-3.0 assays, a bias toward higher viral titer by the bDNA-2.0 assay was noted (P = 0.001). Likewise, although substantial agreement was noted between the results generated by the HCM-2.0 and bDNA-3.0 assays, a bias toward higher viral titer by the bDNA-3.0 assay was noted (P < or = 0.001). The discrepancy between the HCM-2.0 and bDNA-3.0 results was more pronounced when viral loads were >500,000 IU/ml and resulted in statistically significant differences (P < or = 0.001) in determining whether viral loads were above or below 800,000 IU/ml of HCV RNA, the proposed threshold value for tailoring the duration of combination therapy. The expression of quantitative values in HCV international units per milliliter was a strength of both the bDNA-3.0 and HCM-2.0 assays.  相似文献   
72.
A rapid urine culture procedure was evaluated in which positive urines were detected by using light-scatter photometry (Autobac). Specimens were analyzed at 3, 5, and 6 h. Specimens detected as positive at 3 h were then further evaluated by a direct 3-h susceptibility procedure (Autobac) and by a 4-h identification procedure (Micro-ID). Of 949 specimens, 175 had >105 colony-forming units per ml by colony count. Of these latter specimens, 75.4% had been detected by 3 h, and 95.4% were detected by 6 h. Of specimens positive by Autobac at 3 h, 96% (95.7%) had >105 colony-forming units per ml. If pure by Gram stain, those positive specimens were inoculated to direct susceptibility and identification systems. When direct Autobac susceptibilities were compared with the standard Autobac method done from the plate the following day, discrepancy rates were 1.3% very major, 2.1% major, and 7.4% total. The direct identifications were 94% (94.2%) correct when using the Micro-ID manual and a collection of octal patterns unique to this system, in which urine/broth culture inoculum was employed instead of the usual organism colony suspension. Those urine specimens negative after screening at 3 h were evaluated at 5 and 6 h, and an additional 126 specimens were detected as positive. These were then processed by routine plate inoculation, due to the limitations of the work day. By 6 h, 95.4% of specimens with >105 colony-forming units per ml were detected. The 4.6% false-negative results consisted of patients on antibiotics, or slowly growing bacteria suspected of being distal urethral contaminants. Thus, 83.5% of the urine cultures received by 9:00 a.m. (10.6% 3-h positives and 72.9% negative at 6 h) could be evaluated and reported within one 8-h work day.  相似文献   
73.
A reciprocal translocation is described, t(4;21)(q27;p11), which occurs in a balanced carrier mother and her Down's syndrome child, 47,XX,t(4q-;21p+),+21. A review is presented of Down's syndrome associated with reciprocal translations involving chromosome No. 21.  相似文献   
74.
Immunocytochemical staining for papillomavirus antigen was carried out on 1147 consecutive cervical punch biopsy specimens over 12 months. Of 876 cases with cervical intraepithelial neoplasia (CIN) 351, were antigen positive and of 49 cases with histological evidence of human papillomavirus (HPV) infection but no CIN, 14 were positive. There were 204 cases reported to be normal on routine histological examination and 12 cases reported to show features suggestive but not diagnostic of HPV infection. Of the normal group, 24 (12%) were antigen positive and of the equivocal group, two were positive. In 122 of the normal or equivocal groups cytological examination was repeated at the time of colposcopy, and dyskaryosis was reported in 36. In only four cases was disease shown by HPV antigen staining when there was no diagnostic histological or cytological abnormality. HPV antigen staining assists in the recognition of the range of histological changes associated with productive HPV infection but is an insensitive test and has only limited value in supplementing histological and cytological examinations as a diagnostic aid in routine colposcopic pathology.  相似文献   
75.
During a study on the epidemiology of Staphylococcus aureus colonization in newborns, mothers, and hospital staff, S. aureus was isolated from 536 of 1,945 specimens. Ninety-three isolates of S. aureus from the three groups of individuals were included in a study to evaluate the potential of DNA fingerprinting for strain differentiation. The 93 isolates were also phage typed and their plasmid profiles were analyzed. Cleavage of DNA with BamHI resulted in 13 different DNA restriction endonuclease band patterns (DNA REBPs), one of which consisted of eight isolates whose DNA was not cleaved with BamHI. The DNAs from these eight isolates were easily cleaved with HindIII. The different DNA REBPs were stable both during in vitro and in vivo growth and allowed strain differentiation within phage groups or types. We could not show any strong association between DNA REBP classes, phage types or groups, and plasmid profiles. Of the 93 isolates, 27 (29.0%) could not be phage typed and 12 (12.9%) lacked plasmids. We therefore conclude that DNA fingerprinting is a powerful tool, in addition to phage typing and plasmid profile analysis, for strain differentiation of S. aureus.  相似文献   
76.
Blood culture records from 1994 to 1995 from five U.S. medical centers all using the Difco ESP continuous monitoring blood culture system were reviewed retrospectively. Among a total of 7,362 isolates of bacteria and yeasts, only 0.1% of possibly significant isolates would have been missed had blood cultures been routinely incubated for 4 days instead of the 5 days recommended by the manufacturer. Conversely, numerous contaminants, detected only on day 5, would have been eliminated by a 4-day incubation period.  相似文献   
77.
The relationship of toxoplasma antigen(s) to the origin and long-term persistence of the mononuclear cell inflammatory infiltrate that is present in the brains of mice chronically infected with Toxoplasma gondii was studied by using the peroxidase-antiperoxidase immunohistochemical staining technique. C3H/Km mice were infected with the avirulent C37 strain of T. gondii and sequentially sacrificed over the ensuing 107 days. Comparable sections of each brain were prepared for routine light microscopy. Antisera to toxoplasma made in rabbits were used for immunohistological staining, and adjacent slides were also stained with conventional histological stains. The peroxidase-antiperoxidase stain demonstrated toxoplasma tissue cysts, tachyzoites, and intra- and extracellular antigen-antibody reaction products. Early infection was characterized by small tight clusters of free tachyzoites gaining access to brain substance in the absence of an inflammatory response. Once there was disruption of neural parenchyma, a mononuclear cellular infiltrate rapidly ensued. After the first days of infection, mononuclear cells were always present in all infected brains and were anatomically associated with some component of toxoplasma antigen(s). The histological picture of late infection suggested that recurrent episodes of hematogenous dissemination of tachyzoites occurred in infected mice and that such episodes were at least partially responsible for persistence of an antigenic stimulus.  相似文献   
78.
Using multiple PCR primer sets, we tried to optimize the detection of human papillomavirus (HPV) in DNA samples isolated from 361 frozen biopsy specimens from patients with invasive cervical carcinomas. The HPVs detected were placed into three distinct groups, including group I/Inex at Telelab (Skien, Norway) and group Ineg and group II at the Norwegian Radium Hospital (Oslo, Norway). The consensus primer sets were Oli-1b-oli-2i, My09-My11, Gp5-Gp6, and Gp(5+)-Gp6+ from the HPV L1 gene and CpI-CpIIG from the E1 gene. Using these consensus primers together with the type-specific primers from E6-E7, we found that 355 patients (98%) were HPV positive. Type-specific primers for HPV types 11, 16, 18, 31, 33, and 35 detected more HPV-infected patients than the most sensitive consensus primer set, while the three consensus primer sets My, Gp/Gp+, and Cp together detected more HPV-positive patients than the type-specific primers. Testing of sensitivity of the PCR with SiHa cells serially diluted in lymphocytes (HPV-negative cells) indicated a detection limit of 6,300 HPV type 16 DNA copies with consensus primers (My, Gp+, and Cp) and 126 original HPV type 16 DNA copies with type-specific primers. Comparison of the amplification results for consensus L1 primers and type-specific E6-E7 primers indicated the presence of L1 deletions in 23 of 56 samples. The conclusion is that in PCR detection systems, multiple consensus primers and type-specific primers should be used in order to detect all patients harboring HPV.  相似文献   
79.
This is an extension of previous research that has reported on psychosocial risk factors in women participants in the Recurrent Coronary Prevention Project (RCPP). The RCPP women (N = 83) were under 65 years of age, non-diabetic, non-smoking and had experienced a myocardial infarction (MI) at least 6 months prior to the study. Baseline data was available on 80 RCPP subjects. Seventy three non-smoking, coronary disease-free women participants in the Stanford-Sunnyvale Health Improvement Project (SSHIP) served as a control-comparison group. Women with coronary heart disease had higher serum cholesterol than controls. There were no case-control differences in marital status, occupation, or number of children. RCPP women had Videotaped Structured Interview (VSI) Type A scores comparable to those of the SSHIP women, but had significantly higher VSI-hostility scores (p < .01). In addition. the post-MI women were rated more anxious and depressed, and had more avoidance symptoms than controls ( p < .01). Additional analyses involved the 65 RCPP women located at 8.5-year follow-up. In these women, univariate predictors of coronary recurrence (N = 13) were body mass index (kg/m)2. Peel Index, low time urgency (VSI) and high anxiety ( p < .05). Employment status, marital status, and education were not associated with subsequent cardiac events. These exploratory analyses suggest that the relations between heart disease and hostility, anxiety, and depression in women deserve further investigation.  相似文献   
80.
The presence of a damaged tube has been suggested in recent studies to have a negative effect on in-vitro fertilization (IVF) outcome. Performing bilateral salpingectomy prior to IVF to maximize pregnancy rates may also result in unnecessary surgery. This case is also an example of the occurrence of interstitial pregnancy after salpingectomy. This unusual type of ectopic pregnancy must be kept in mind when evaluating a patient suspected of a possible early abnormal gestation after assisted reproductive technolologies.   相似文献   
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