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991.
992.
AM Assiri KG Carnahan TL Ott 《American journal of reproductive immunology (New York, N.Y. : 1989)》2006,55(6):406-406
Ovine Mx1 (oMx1) is expressed in the uterus during the estrous cycle and is strongly up-regulated during early pregnancy in the uterus and peripheral blood leukocytes. Mx proteins are GTPases which are important elements in innate immunity. Our results showed that steroids are required for oMx1 protein induction by IFN in the uterus. To addresses the role of IFN in regulating oMx1 expression, a 2.1 kb fragment containing 1.7 kb of the promoter/enhancer, exon1 and partial intron A was cloned. Serial deletions were prepared along with a clone that contained the 2 promoter-ISREs (-101 & −145) but not the intronic-ISRE (+224). An ovine uterine cell line was transfected with reporter plasmids driven by the oMx1 promoter deletion constructs. The full-length promoter was induced by IFN in a dose- and time-dependent manner. Treatment with 10,000 AVU/mL IFN increased luciferase activity 5- and 10-fold at 3 and 12 hr, respectively. Promoter deletions showed the 2 proximal ISRE (−101 and −145), but not an intronic ISRE (+244), were required for maximal response. Deletion of a distal region (−920 to −715) resulted in decreased luciferase activity (~4-fold). However, subsequent deletion of the −715 to −437 region restored maximal promoter response (~10-fold). Results suggest that regions −920 to −715 and −715 to −437 have positive and negative regulatory element binding sites, respectively. The importance of the 2 proximal ISRE sites for oMx1 promoter activation is consistent with results for the human MxA promoter. An intronic ISRE is present in the human MxA gene, however, this site may not be required for oMx1 promoter activation by IFN. Identifying positive and negative regulatory regions in oMx1 promoter may help elucidate the unique regulation of Mx1 during early pregnancy. 相似文献
993.
Maranchie JK Afonso A Albert PS Kalyandrug S Phillips JL Zhou S Peterson J Ghadimi BM Hurley K Riss J Vasselli JR Ried T Zbar B Choyke P Walther MM Klausner RD Linehan WM 《Human mutation》2004,23(1):40-46
von Hippel Lindau disease (VHL) is an autosomal dominant familial cancer syndrome linked to alteration of the VHL tumor suppressor gene. Affected patients are predisposed to develop pheochromocytomas and cystic and solid tumors of the kidney, CNS, pancreas, retina, and epididymis. However, organ involvement varies considerably among families and has been shown to correlate with the underlying germline alteration. Clinically, we observed a paradoxically lower prevalence of renal cell carcinoma (RCC) in patients with complete germline deletion of VHL. To determine if a relationship existed between the type of VHL deletion and disease, we retrospectively evaluated 123 patients from 55 families with large germline VHL deletions, including 42 intragenic partial deletions and 13 complete VHL deletions, by history and radiographic imaging. Each individual and family was scored for cystic or solid involvement of CNS, pancreas, and kidney, and for pheochromocytoma. Germline deletions were mapped using a combination of fluorescent in situ hybridization (FISH) and quantitative Southern and Southern blot analysis. An age-adjusted comparison demonstrated a higher prevalence of RCC in patients with partial germline VHL deletions relative to complete deletions (48.9 vs. 22.6%, p=0.007). This striking phenotypic dichotomy was not seen for cystic renal lesions or for CNS (p=0.22), pancreas (p=0.72), or pheochromocytoma (p=0.34). Deletion mapping revealed that development of RCC had an even greater correlation with retention of HSPC300 (C3orf10), located within the 30-kb region of chromosome 3p, immediately telomeric to VHL (52.3 vs. 18.9%, p <0.001), suggesting the presence of a neighboring gene or genes critical to the development and maintenance of RCC. Careful correlation of genotypic data with objective phenotypic measures will provide further insight into the mechanisms of tumor formation. 相似文献
994.
Talbot K; Ponting CP; Theodosiou AM; Rodrigues NR; Surtees R; Mountford R; Davies KE 《Human molecular genetics》1997,6(3):497-500
The Survival Motor Neuron (SMN) gene shows deletions in the majority of
patients with Spinal Muscular Atrophy (SMA), a disease of motor neuron
degeneration. To date only two missense mutations have been reported in SMN
in patients with SMA. The fact that no SMN-homologues have been forthcoming
from data-base searching has resulted in a lack of hypotheses concerning
the structural and functional consequences of these mutations. Recently SMN
has been shown to interact with heterogeneous nuclear ribonucleoproteins
(hnRNPs) suggesting a role in mRNA metabolism. We describe a novel missense
mutation and the subsequent identification of a triplicated
tyrosine-glycine (Y-G) peptide sequence at the C-terminal of SMN which
encompasses each of the three predicted amino acid sequence substitutions.
We have identified apparent orthologues of SMN in Caenorhabditis elegans
and Schizosaccharomyces pombe. These sequences retain the highly conserved
Y-G motif and provide additional support for a role of SMN in mRNA
metabolism.
相似文献
995.
Seminal plasma alpha-glucosidase activity and male infertility 总被引:7,自引:1,他引:7
Mahmoud AM; Geslevich J; Kint J; Depuydt C; Huysse L; Zalata A; Comhaire FH 《Human reproduction (Oxford, England)》1998,13(3):591-595
Measurement of alpha-glucosidase (alpha-GLUC) activity by means of a simple
colorimetric test using a commercial kit (EpiScreen; FertiPro, Lotenhulle,
Belgium) yielded results that were strongly correlated with the values
obtained for the neutral iso-enzyme measured by a fluorimetric reference
method (r=0.85, P=0.003, n=13). The former method was characterized by a
low intra- and inter-coefficient of variation (6.6 and 4.3% respectively).
Vasectomized men with azoospermia (n=27) had a significantly lower
alpha-GLUC activity in semen than vasectomized men with residual
spermatozoa present (n=11, P < 0.01) and men with azoospermia of primary
testicular origin (n=33, P < 0.01). Receiver operating curve (ROC)
analysis showed alpha-GLUC measurement to be reasonably accurate in
differentiation between cases with obstructive versus testicular
azoospermia at criterion value 13.5 U/l (sensitivity=82%, specificity=
70%). In cases with spermatozoa present, alpha-GLUC activity and output per
ejaculate were positively correlated with sperm concentration (r=0.53 and
0.38, n=472), linear velocity (r=0.35 and 0.30, n=224), curvilinear
velocity (r=0.32 and r=0.29, n=224), semen adenosine triphosphate (r=0.35
and 0.26, n=64), the concentration of 5alpha-dihydrotestosterone (r=0.31
and 0.29, n=74), and gamma-glutamyltransferase activity (r=0.62 and 0.32,
n=275) in seminal plasma. The activity of alpha-GLUC was inversely
correlated with ROS generation after 12-myristate, 13-acetate phorbol ester
stimulation (r=-0.27, n=104), and both alpha-GLUC activity and total output
were inversely correlated with the concentration of peroxidase- positive
white blood cells among samples with > or =1x10(6)/ml of these cells
(r=-0.30 and -0.19, n=165). It is concluded that simple photometric
measurement of alpha-GLUC activity in seminal plasma reflects the
functional state of the epididymis and may be helpful for the differential
diagnosis of certain cases with azoospermia.
相似文献
996.
997.
Srikar Anagoni Nagaraja Mudhigeti Mohan Alladi Verma Anju Padmalatha AM Usha Kalawat 《Indian journal of medical microbiology》2022,40(3):427-432
PurposeA large number of new molecular or virology laboratories have been established to increase the testing capacity for SARS-CoV-2. Due to heavy workload, there is delay in testing of samples. In order to avoid the negative effect of delayed testing on RTPCR results guidelines are issued from WHO and CDC to transport samples in cold chain. However, in pandemic situations the recommended guidelines for transport and storage conditions are often compromised. This study was conducted to evaluate the effect of sample storage conditions at different temperatures on the results of RT PCR test.MethodsTotal 275 samples were included in this study, among these 126 samples tested positive and 149 samples tested negative. All samples were aliquoted into two and the aliquotes stored in duplicate at 4 ?°C and room temperature. All aliquots stored at both the temperatures were tested by RTPCR every 24 hours up to 5 days.ResultsDiagnostic accuracy decreased from day1 to day 5 at both the storage temperatures i,e 4 ?°C and room temperature in comparison to the initial day results. Positivity decreased on an average of 9.02% at 4 ?°C and at 9.27% at room temperature per day. Among total 126 positive samples on an average false negative and failure of internal control at 4 ?°C and room temperature was 8.86%, 8.22% and 3.64%, and 4.12%, respectively. All the samples with CT value ?< ?30 remained positive at both temperatures up to 5 days. Few samples with >30 CT value showed variable results i.e. positive, negative or internal control failure from day 1 (2nd day after sample collection) onwards.ConclusionsThere was no significant difference between RT PCR results of samples stored at 4 ?°C and room temperature up to 5 days of collection. However internal control failure was more in samples stored at room temperature. Therefore, samples received without cold chain also may be processed by RTPCR and should not be rejected. 相似文献
998.
Evaluation of the performance of hysterosalpingo contrast sonography in 500 consecutive, unselected, infertile women 总被引:1,自引:1,他引:1
Hamilton JA; Larson AJ; Lower AM; Hasnain S; Grudzinskas JG 《Human reproduction (Oxford, England)》1998,13(6):1519-1526
The performance of hysterosalpingo contrast sonography (Hy Co Sy) as a
first-line, outpatient investigation of tubal patency was examined in 500
consecutive, infertile women, at one centre. Hy Co Sy was completed in 463
(92.6%) cases, using a galactose microbubble contrast agent (Echovist-200)
and transvaginal sonography. Initial plain scanning identified adnexal
pathology in 198 women (39.6%). Examination with Echovist was attempted for
905 tubes and only 67 (7.4%) were not assessable; after the first 100 women
this decreased to 35 tubes (4.8%). A sonographic appearance compatible with
blocked tubes was found on 118 (14.1%) occasions but it was also possible
to identify variations in the appearance/filling/spilling patterns of
individual tubes which increased the number assessed as abnormal to 193
(23.0%). Comparison with laparoscopy and dye chromopertubation findings
from the past three years was possible for 185 (37%) women, representing
282 tubes, which gave Hy Co Sy an overall concordance rate of 85.8%,
sensitivity of 90.4%, specificity of 70.3%, positive predictive value of
91.2% and negative predictive value of 68.2%. Some 51.0% of women described
only mild discomfort and there were no significant postprocedure
complications. Hy Co Sy appears to be an acceptable first- line screen and
may select out women in whom more invasive investigations are likely to
reveal pathology.
相似文献
999.
1000.
Linkage analysis of candidate regions for coeliac disease genes 总被引:5,自引:0,他引:5
Houlston RS; Tomlinson IP; Ford D; Seal S; Marossy AM; Ferguson A; Holmes GK; Hosie KB; Howdle PD; Jewell DP; Godkin A; Kerr GD; Kumar P; Logan RF; Love AH; Johnston S; Marsh MN; Mitton S; O'Donoghue D; Roberts A; Walker-Smith JA; Stratton MF 《Human molecular genetics》1997,6(8):1335-1339
A strong HLA association is seen in coeliac disease [specifically to the
DQ(alpha1*0501,beta1*0201 heterodimer], but this cannot entirely account
for the increased risk seen in relatives of affected cases. One or more
genes at HLA-unlinked loci also predispose to coeliac disease and are
probably stronger determinants of disease susceptibility than HLA. A recent
study has proposed a number of candidate regions on chromosomes 6p23
(distinct from HLA), 6p12, 3q27, 5q33.3, 7q31.3, 11p11, 15q26, 19p13.3,
19q13.1, 19q13.4 and 22cen for the location of a non-HLA linked
susceptibility gene. We have examined these regions in 28 coeliac disease
families by linkage analysis. There was excess sharing of chromosome 6p
markers, but no support for a predisposition locus telomeric to HLA. No
significant evidence in favour of linkage to coeliac disease was obtained
for chromosomes 3q27, 5q33.3, 7q31.3, 11p11, 19p13.3, 19q13.1, 19q13.4 or
22cen. There was, however, excess sharing close to D15S642. The maximum
non-parametric linkage score was 1.99 (P = 0.03). Although the evidence for
linkage of coeliac disease to chromosome 15q26 is not strong, the well
established association between coeliac disease and insulin dependent
diabetes mellitus, together with the mapping of an IDDM susceptibility
locus (IDDM3) to chromosome 15q26, provide indirect support for this as a
candidate locus conferring susceptibility to coeliac disease in some
families.
相似文献