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排序方式: 共有451条查询结果,搜索用时 15 毫秒
421.
Lower-space, single-contrast arthrography and dual-space, double-contrast arthrotomography were sequentially applied to 58 fresh temporomandibular joint (TMJ) autopsy specimens, and the findings were compared with observations in corresponding cryosections. Both modalities had high accuracy rates (greater than or equal to 84%) and no statistically significant differences between the two techniques were found. A side-by-side comparison of the two types of arthrograms, however, revealed that video tape recording of lower-space, single-contrast arthrography was superior in demonstrating joint dynamics and that dual-space, double-contrast arthrotomography was superior in demonstrating the soft-tissue anatomic features of the joint. It appears that lower-space, single-contrast arthrography can be recommended for examination of patients with clicking, catching, and intermittent locking, and that dual-space, double-contrast arthrotomography is preferable when information about morphologic alterations is clinically more important than information about joint dynamics. 相似文献
422.
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424.
Brody JM; Miller DK; Zeman RK; Klappenbach RS; Jaffe MH; Clark LR; Benjamin SB; Choyke PL 《Radiology》1986,159(2):347-348
A Haitian man with acquired immunodeficiency syndrome (AIDS), fever, malaise, and diarrhea is described. A computed tomographic (CT) scan showed a retrogastric mass with an associated ulcer. An upper gastrointestinal tract study showed an ulcer with both benign and malignant features. Endoscopy revealed a malignant-appearing ulcer, but cultures and histologic examinations of surgical biopsy specimens indicated gastric tuberculosis. The relationship between tuberculosis and AIDS is discussed. 相似文献
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427.
1 背景
目前宫颈上皮内瘤样病变(CTV)的治疗主要是根据疾病的性质和范围行局部切除或切除。阴道镜检查出现以前,传统上所有病灶在全麻下都用刀行锥切活检或电凝法行点根治术,而现在更趋向于各种可用于门诊病人的更保守的局部切除和切除治疗。 相似文献
428.
Schell U; Wienberg J; Kohler A; Bray-Ward P; Ward DE; Wilson WG; Allen WP; Lebel RR; Sawyer JR; Campbell PL; Aughton DJ; Punnett HH; Lammer EJ; Kao FT; Ward DC; Muenke M 《Human molecular genetics》1996,5(2):223-229
Holoprosencephaly (HPE) is a common developmental defect involving the
brain and face in humans. Cytogenetic deletions in patients with HPE have
localized one of the HPE genes (HPE2) to the chromosomal region 2p21. Here
we report the molecular genetic characterization of nine HPE patients with
cytogenetic deletions or translocations involving 2p21. We have determined
the parental origin of the deleted chromosomes and defined the HPE2
critical region between D2S119 and D2S88/D2S391. As a first step towards
cloning the HPE2 gene which is crucial for normal brain development we have
constructed a YAC contig which spans the smallest region of deletion
overlap. Several of these YACs could be identified which span three
different 2p21 breakpoints in HPE patients. These YACs narrow the HPE2
critical region to less than 1 Mb and are now being further analyzed to
identify the gene causing holoprosencephaly on chromosome 2.
相似文献
429.
Birth from cryopreserved embryos following in-vitro maturation of oocytes and intracytoplasmic sperm injection 总被引:2,自引:9,他引:2
Edirisinghe WR; Junk SM; Matson PL; Yovich JL 《Human reproduction (Oxford, England)》1997,12(5):1056-1058
This case report describes the birth of a baby following the transfer of
cryopreserved embryos generated from intracytoplasmic sperm injection
(ICSI) carried out on the second day after oocyte pick-up of
in-vitro-matured metaphase I and germinal vesicle stage oocytes. The couple
had a history of three failed intrauterine insemination attempts and
reduced fertilization rates in two previous in-vitro fertilization (IVF)
cycles. In the IVF-ICSI treatment cycle, 6/11 mature oocytes became
fertilized following ICSI on the first day. However, the patient failed to
conceive following the transfer of three embryos. Five oocytes were
immature (two at metaphase I stage and three with a germinal vesicle) and
these were cultured overnight. All had extruded a polar body by the
following day and ICSI was therefore performed; four oocytes became
fertilized, and were cryopreserved at the pronulear stage in propanediol.
In the next treatment cycle, transfer of frozen embryos was planned. The
pronuclear zygotes were thawed and cultured for 24 h prior to the transfer
of two embryos in a cycle stimulated with low doses of follicle stimulating
hormone. This resulted in a pregnancy and the delivery of a healthy baby
boy. In-vitro maturation of metaphase I and germinal vesicle oocytes which
are routinely collected in IVF-ICSI cycles, followed by second day ICSI
fertilization, may provide a valuable source of embryos for infertile
couples.
相似文献
430.
Limprasert P; Nouri N; Heyman RA; Nopparatana C; Kamonsilp M; Deininger PL; Keats BJ 《Human molecular genetics》1996,5(2):207-213
Machado-Joseph disease (MJD) is an autosomal dominant neurodegenerative
disorder associated with an unstable and expanded CAG repeat. We analyzed
this locus from various sources including MJD families, Acadian, African
American, Caucasian, Greenland Inuit and Thai populations. The range of the
CAG repeat size was 14-40 in the normal alleles while the MJD alleles
contained 73-78 repeats in our studies. We found 25 different alleles on
normal chromosomes with a heterozygosity of 0.86 in combined populations.
The most common alleles were 23 (22.9%) and 14 (25.5%) repeats. We also
examined 16 chimpanzees and various Old World monkeys: a pigtail macaque, a
mangabey and 12 rhesus macaques. The DNA sequences surrounding the CAG
repeat did not vary among species. The range of the number of the CAG
repeats is 13-14 in macaques, 16 in mangabey and 14-20 in chimpanzees.
Variant CAA or AAG triplets in the CAG repeat tracts were found in all 268
human, 28 monkey and 32 chimpanzee chromosomes. As reported in a previous
study [Kawaguchi et al. (1994) Nature Genet. 8, 221-228] the common variant
positions were the third (CAA), fourth (AAG) and sixth (CAA) positions.
However, we found three human chromosomes containing CAG at the sixth
position and the mangabey had AAG at the ninth position. In addition, we
found CAG at the fourth position and AAG at the sixth position in all
macaque chromosomes. The nucleotide following the CAG repeat tract was
usually G in all species studied. However, we sometimes found C at this
position in human and chimpanzee chromosomes. Interestingly, this variant C
was found in all expanded chromosomes and in 54.5% of chromosomes with
27-40 CAG repeats but it was not found in any chromosomes with less than 20
CAG repeats. We hypothesize that the variant C may be associated with CAG
repeat instability.
相似文献