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991.
Yotova V Lefebvre JF Kohany O Jurka J Michalski R Modiano D Utermann G Williams SM Labuda D 《Human genetics》2007,122(5):431-443
Genetic variability of the compound interrupted microsatellite DXS1238, in intron 44 of the dystrophin gene, provides evidence
for a complex structure of the ancestral population that led to the emergence of modern humans. We sequenced DXS1238 in 600
X-chromosomes from all over the world. Forty four percent of African-specific chromosomes belong to the ancestral lineage
that did not participate in the out-of-Africa expansion and subsequent colonization of other continents. Based on the coalescence
analysis these lineages separated from those that contributed to the out-of-Africa expansion 366 ± 136 thousands years ago
(Kya). Independently, the analysis of the variance in the repeat length and of the decay of the ancestral alleles of the two
DXS1238 repeats, GT and GA, dates this separation at more than 200 Kya. This suggests a complex demographic history and genetic
structure of the African melting pot that led to the emergence of modern humans and their out-of-Africa migration. The subsequent
subdivisions of human populations among different continents appear to be preceded by even more structured population history
within Africa itself, which resulted from a restricted gene flow between lineages allowing for genetic differences to accumulate.
If the transition to modern humans occurred during that time, it necessarily follows that genes associated with this transformation
spread between subpopulations via gene flow. Otherwise, in spite of subsequent anatomical variation, Homo sapiens as a species could have emerged in Africa already between 300 and 200 Kya, i.e. before the mitochondrial DNA and well before
the Y-chromosome most recent common ancestors.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
992.
Bolanowski M Bar-Andziak E Kos-Kudła B Krzyzanowska-Swiniarska B Lewiński A Lomna-Bogdanov E Milewicz A Sowiński J Zgliczyński W 《Endokrynologia Polska》2007,58(4):350-3; discussion 354-5
Consensus statement of the Polish Society of Endocrinology, regarding presurgical somatostatin analogs in acromegaly has been presented. It is suggested to administer depot somatostatin analog (Octreotide LAR at the dose 20 mg and then 30 mg or equivalent doses of Lanreotide Autogel 90/120 mg every 4 weeks) in order to normalize or suppress to a maximal extent GH and IGF-1 concentrations. The period of therapy in case of microadenoma would be at least 3 months (targets: biochemical improvement, reduced risk of disease's complications, perioperative risk reduction, inhibition of tumor growth). The period of therapy in case of macroadenoma would be at least 6 months, until maximal possible reduction of GH and IGF-1 concentrations (targets: tumor shrinkage, biochemical improvement, reduced risk of disease's complications, perioperative risk reduction). Using an uniform approach in a group, as numerous as possible, of treated patients would allow objective evaluation of long-term efficacy of the treatment. 相似文献
993.
Matuszewska G Marek B Kajdaniuk D Przywara-Chowaniec B Jarzab J Jarzab B 《Endokrynologia Polska》2007,58(5):384-396
INTRODUCTION: Patients with differentiated thyroid carcinoma have to undergo radical surgical treatment, which includes total thyreoidectomy, radioiodine therapy and a life-time suppressive therapy with L-thyroxine. The aim of this study was a prospective evaluation of left ventricular hypertrophy during L suppressive-thyroxine treatment in patients treated for differentiated thyroid carcinoma. MATERIAL AND METHODS: The examined group comprised 50 patients with differentiated thyroid carcinoma, treated by total thyroidectomy and 131I therapy. Echocardiographic measurements were needed for estimation of left ventricular mass and its index, according to recommendations of American Echocardiography Society. RESULTS: During two-years long suppressive therapy we observed a significant rise in left ventricular mass. In woman group left ventricular mass was increased from 168+/-39 g to 204+/-45 g (p<0.001) and in men from 205+/-60 to 320+/-21 g. Likewise, left ventricular mass index was increased in women group from 96+/-18 g/m(2) to 116+/-25 g/m(2) (p<0.001) and in men group from 107+/-37 g/m(2) to 158+/-28 g/m(2). Simultaneous treatment with bisoprolol caused a regression of left myocardial hypertrophy. Already after 6 months of simultaneous treatment with L-thyroxin and bisoprolol, for left ventricular mass was reduced to normal: in woman 165+/-35 g, and in men to 178+/-38 g. Analogous results were obtained left ventricular mass index. After 6 months it was reduced to 94+/-12 g/m(2) in woman and in men to 132+/-32 g/m(2). CONCLUSIONS: 1. In differentiated thyroid cancer patients, treated postoperatively with L-thyroxine suppressive therapy, left ventricular hypertrophy is observed already during the first year of suppressive therapy and progresses during the next year of treatment. 2 Addition of a beta-adrenergic antagonist to suppressive doses of L-thyroxine causes a regression of left ventricular hypertrophy, thus, beta-adrenergic antagonists should be administered in this group of patients. 相似文献
994.
INTRODUCTION: The aim of study was to establish the effectiveness of radioiodine therapy using 131I in the group of patients with multinodular large non-toxic goiter. MATERIAL AND METHODS: Therapy was undertaken in female patients disqualified from surgery due to high risk and these patients who didn't agree to surgery. Studies were performed in 7 women (age range: 62-82 yrs) with large goiters (2nd degree according to WHO classification and goiter volume assessed by USG over 100 cm(3)). Serum TSH, fT4, fT3, antithyroid antibodies (TPOAb, TgAb, TRAb) levels, urinary iodine concentration (UIE) were estimated in all patients parallel with radioiodine uptake test (after 5 and 24 hours), 131I thyroid scintigraphy and fine needle biopsy to exclude neoplasmatic transformation. These studies and therapy with 22 mCi 131I were repeated every 3 months. RESULTS: Before therapy median thyroid volume was approximately 145 cm(3) and during therapy gradually decreased to 76 cm(3) after 6 months and to 65 cm(3) after 12 months. Increase of TRAb can be a inhibiting factor of thyroid volume reduction. Other antithyroid antibodies showed marked tendency to rise but without significant correlation with radioiodine uptake and goiter reduction. After 12 months we found 2 patients with clinical and laboratory hypothyroidism. CONCLUSIONS: In some cases of multinodular large non-toxic goiter, the radioiodine therapy can be the best alternative way for L-thyroxine treatment or surgery therapy. The fractionated radioiodine therapy of multinodular large non-toxic goiter is safe and effective method but continuation of nodules observation is necessary. 相似文献
995.
The distribution of several arabinogalactan protein and pectic epitopes were studied during organogenesis in androgenic callus
of wheat. In cell wall of mature and degenerating parenchyma cells, the arabinogalactan epitopes JIM4, JIM14, JIM16 or LM2
were expressed differently according to the cells location. LM2 was observed also in meristematic cells of regenerated shoot
buds and leaves. Anti-pectin JIM7 labelled the wall of meristematic cells but fluorescence was strongest in outer walls of
surface cells of callus and shoot buds coated by extracellular matrix surface network (ECMSN). During leaves growth the ECMSN
disappeared, and JIM7 fluorescence decreased. JIM5 epitope was abundant in the cell walls lining the intercellular spaces
of callus parenchyma and in tricellular junctions within regenerated buds and leaves. 相似文献
996.
Six derivatives of 2-aminoindane-2-phosphonic acid and 1-aminobenzylphosphonic acid were synthesized. The compounds were tested both as inhibitors of buckwheat phenylalanine ammonia-lyase (in vitro) and as inhibitors of anthocyanin biosynthesis (in vivo). (+/-)-2-Amino-4-bromoindane-2-phosphonic acid was found to be the strongest inhibitor from investigated compounds. The results obtained are a basis for design of phenylalanine ammonia-lyase inhibitors useful in the enzyme structure studies in photo labelling experiments. 相似文献
997.
Tocochroanols belong to a group of compounds comprising tocopherols and tocotrienols, known as vitamin E. Apart from the well known antioxidant properties of these compounds, there is increasing evidence accumulating for their additional function in men, manifesting in lowering of blood cholesterol level, anticancer and neuroprotective action, especially in the case of tocotrienols. The present article describes the structure of tocochromanols, their occurrence and biosynthesis in plants. The mechanism of antioxidant action of these compounds and recently recognized additional functions in plants and animals are presented. 相似文献
998.
Kikuchi T Naruse TK Onizuka M Li S Kimura T Oka A Morishima Y Kulski JK Ichimiya S Sato N Inoko H 《Immunogenetics》2007,59(2):99-108
Despite matching donors and recipients for the human leukocyte antigens (HLAs) expressed by the major histocompatibility genomic
region of the short arm of chromosome 6, several recipients still develop acute graft-versus-host disease (aGVHD) after bone
marrow transplantation (BMT). This is possibly due to non-HLA gene polymorphisms, such as minor histocompatibility antigens
(mHas) and genes coding for cytokines. However, a detailed genetic background for aGVHD has not yet been established. To find
novel susceptibility and/or protective loci for aGVHD, a whole genome-wide association study of donors and recipients needs
to be performed. As the first step to such a study, we retrospectively analyzed polymorphisms of 155 microsatellite markers
spread across the long arm of chromosome 22 in 70 pairs of HLA-matched unrelated BMT donors and recipients. We performed individual
typing and then compared the markers’ allele frequencies (1) between all the aGVHD (grades III and IV GVHD) and GVHD-free
(grade 0 GVHD) groups in donors and recipients and (2) between the aGVHD and aGVHD-free groups in donor/recipient pairs that
were matched and mismatched for the microsatellite marker’s allele. Screening of the microsatellite markers revealed five
loci with a significant difference between the aGVHD and GVHD-free groups and revealed eight loci on chromosome 22, where
the microsatellite allele mismatched markers were associated with aGVHD. This screening analysis suggests that several aGVHD-associated
susceptible and protective loci exist on chromosome 22, which may encompass novel gene regions that need to be elucidated
for their role in aGVHD. 相似文献
999.
Benedikt Linder Susanne Weber Kai Dittmann Jerzy Adamski Heidi Hahn Anja Uhmann 《The Journal of biological chemistry》2015,290(32):19614-19628
The Patched1 (Ptch)-mediated inhibition of Smoothened (Smo) is still an open question. However, a direct Ptch/Smo interaction has been excluded, Smo modulators were identified, but the endogenous signal transmitting molecule remains undiscovered. Here, we demonstrate that calcitriol, the hormonally active form of vitamin D3, is an excellent candidate for transmission of Ptch/Smo interaction. Our study reveals that Ptch expression is sufficient to release calcitriol from the cell and that calcitriol inhibits Smo action and ciliary translocation by acting on a site distinct from the 7-transmembrane domain or the cysteine-rich domain. Moreover calcitriol strongly synergizes with itraconazole (ITZ) in Smo inhibition, which did not result from elevated calcitriol bioavailability due to ITZ-mediated 24-hydroxylase inhibition but rather from a direct interaction of the compounds at the level of Smo. Together, we suggest that calcitriol represents a possible endogenous transmitter of Ptch/Smo interaction. Moreover calcitriol or calcitriol derivatives combined with ITZ might be a treatment option of Hedgehog-associated cancers. 相似文献
1000.
Jolanta Dłużewska Kamil Zieliński Beatrycze Nowicka Renata Szymańska Jerzy Kruk 《Plant, cell & environment》2015,38(12):2698-2706
In the present study, we have identified new prenyllipid metabolites formed during high light stress in Arabidopsis thaliana, whose origin and function remained unknown so far. It was found that plastoquinone‐C accumulates mainly in the reduced form under high light conditions, as well as during short‐term excess light illumination both in the wild‐type and tocopherol biosynthetic vte1 mutant, suggesting that plastoquinone‐C, a singlet oxygen‐derived prenyllipid, is reduced in chloroplasts by photosystem II or enzymatically, outside thylakoids. Plastoquinone‐B, a fatty acid ester of plastoquinone‐C, was identified for the first time in Arabidopsis in high light grown wild‐type plants and during short‐time, excess light illumination of the wild‐type plants and the vte1 mutant. The gene expression analysis showed that vte2 gene is most pronouncedly up‐regulated among the prenyllipid biosynthetic genes under high light and induction of its expression is mainly caused by an increased level of singlet oxygen, as was demonstrated in experiments with D2O‐treated plants under excess light conditions. 相似文献