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91.
92.
艾滋病合并隐球菌感染17例尸检材料的临床病理学研究 总被引:4,自引:0,他引:4
在151例艾滋病尸检材料中发现17例合并隐球菌感染,均经病理学确诊,患者男15名,女2名,平均43.6岁。12例发生脑膜炎、肺炎和淋巴结炎各7例,尚见脾(6例)、肾(5例)等器官受累。9例为播散性感染。病变为慢性肉牙肿性,其中见有隐球菌。本文描述隐球菌性脑膜炎、肺炎等临床病理学表现,并讨论其病变特征与病理诊断问题。 相似文献
93.
94.
A 19-kb CpG Island Associated with Single-minded Gene 2 in Down Syndrome Chromosomal Region 总被引:1,自引:0,他引:1
Osoegawa Kazutoyo; Okano Saishi; Kato Yasutake; Nishimura Yukinobu; Soeda Eiichi 《DNA research》1996,3(3):175-179
To help in isolating the genes involved in Down syndrome, wesought CpG islands in 4 Mb cosmid/PAC contigs spanning mostof the 21q.22.2 band using seven rare cutting enzymes. A strikingfeature was observed upstream of hSIM2 where at least 41 rare-cuttingsites were clustered within a 20-kb region. To investigate thestructure of the cluster, a cosmid containing hSIM2 was submittedto shotgun sequencing. Sequence analysis revealed that the clusterwas a long CpG island extending 19, 128 nucleotides which includesin the first and second exons of hSIM2. Taken together withour observation in which the CpG islands were concentrated within1.2 Mb around hSIM2, we propose that this region functions asan R-band, and the cluster provides a unique element for markingof DNA for the spatial and temporal expression of the hSIM2locus. 相似文献
95.
Chromosomal changes through pericentric inversions play an important role in the origin of species. Certain pericentric inversions are too minute to be detected cytogenetically, thus hindering the complete reconstruction of hominoid phylogeny. The advent of the fluorescence in situ hybridization (FISH) technique has facilitated the identification of many chromosomal segments, even at the single gene level. Therefore the cosmid probe for Prader-Willi (PWS)/Angelman syndrome to the loci on human chromosome 15 [ql 1-12] is being used as a marker to highlight the complementary sequence in higher primates. We hybridized metaphase chromosomes of chimpanzee (PTR), gorilla (GGO), and orangutan (PPY) with this probe (Oncor) to characterize the chromosomal segments because the nature of these pericentric inversions remains relatively unknown. Our observations suggest that a pericentric inversion has occurred in chimpanzee chromosome (PTR 16) which corresponds to human chromosome 15 at PTR 16 band pl 112, while in gorilla (GGO 15) and orangutan (PPY 16) the bands q11-12 complemented to human chromosome 15 band q11-12. This approach has proven to be a better avenue to characterize the pericentric inversions which have apparently occurred during human evolution. Genetic divergence in the speciation process which occurs through chromosomal rearrangement needs to be reevaluated and further explored using newer techniques.Correspondence to: R.S. Verma 相似文献
96.
Sandra L. Davis 《Sexual plant reproduction》1997,10(5):293-299
It has been hypothesized that females of some dioecious species maintain stamens that produce sterile pollen as a means of
attracting pollinators to promote greater seed set. However, this hypothesis has rarely been tested. This paper examines the
role of pollinators in the maintenance of sterile stamens in the cryptically dioecious species, Thalictrum pubescens. Wind was found to contribute to pollination; branches of female T. pubescens enclosed in cheesecloth to exclude insects but not wind were still able to set seed. Therefore, females may not need the stamens
for pollination. In 1994, insects were found to discriminate against emasculated female flowers, but this discrimination did
not lead to a significant difference in either the amount of pollen received or seed set. In 1995, emasculation was combined
with the addition of pollen to determine if emasculated females were pollen limited. No significant effect of pollen addition
or emasculation was found. Emasculated branches in the pollen-addition treatment appeared to have slightly lower seed set
than non-emasculated branches that received pollen, indicating that the slight reduction in seed set was caused by emasculation
rather than pollen limitation. Since stamens do not appear to be maintained as pollinator attractants, other explanations,
such as genetic constraints, must be investigated.
Received: 4 February 1997 / Revision accepted: 20 May 1997 相似文献
97.
Pollination Ecology of Pedicularis in the Teton Mountain Region 总被引:1,自引:0,他引:1
LAZARUS WALTER MACIOR 《Plant Species Biology》1995,10(2):77-82
98.
Naoto Sugiura 《Ecological Research》1995,10(2):171-177
Anthecological observations of an orchidBletilla striata were carried out in Kobe, Japan. The purplish pink flowers were visited by 26 species of insects belonging to Hymenoptera,
Diptera and Lepidoptera, although the flower did not offer food rewards of any kind. Candidates for pollination were seven
species of aculeate Hymenoptera with a body size that well fitted the space in between the column and labellum. The most effective
candidate was the male of the longhorn beeTetralonia nipponensis, judging from its abundance and legitimate intrafloral behavior. The female ofT. nipponensis and the other six species also contributed to promote out-crossing, but to a lesser extent than the maleT. nipponensis, since they occasionally exhibited illegitimate intrafloral behaviors for pollination and also, their flower visitation rate
was lower. 相似文献
99.
E. Papadopulos-Eleopulos V. F. Turner J. M. Papadimitriou H. Bialy 《World journal of microbiology & biotechnology》1995,11(2):135-143
The data widely purporting to show the existence and heterosexual transmission in Africa of a new syndrome caused by a retrovirus which induces immune deficiency are critically evaluated. It is concluded that both acquired immune deficiency (AID) and the symptoms and diseases which constitute the clinical syndrome (S) are of long standing in Africa, affect both sexes equally and are caused directly and indirectly by factors other than human immunodeficiency virus (HIV). Seropositivity to HIV in Africans usually represents no more than cross-reactivity caused by an abundance of antibodies induced by the numerous infectious and parasitic diseases which are endemic in Africa. The apparently high prevalence of AIDS and HIV seropositives is therefore not surprising and is not proof of heterosexual transmission of either HIV or AIDS.E. Papadopulos-Eleopulos is with the Department of Medical Physics, The Royal Perth Hospital, Perth 6000, Western Australia, Australia; V.F. Turner is with the Department of Emergency Medicine, The Royal Perth Hospital, Perth 6000, Western Australia, Australia, J.M. Papadimitriou is with the Department of Pathology, University of Western Australia, Perth, Western Australia. H. Bialy is with Bio/Technology, 65 Becker St, New York, NY 10012, USA. 相似文献
100.