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991.
Bovine papillomavirus type 4 (BPV-4) morphologically transforms primary bovine cells in vitro only in the presence of an activated ras gene. The transformed cells are capable of anchorage-independent growth, but are not immortal and are incapable of inducing tumors in nude mice, suggesting that other events are needed to convert the cells to the fully transformed phenotype. We show here that treatment of the cells with a single dose of the flavonoid quercetin leads to full oncogenic transformation of cells transfected with BPV-4 and ras. Quercetin is one of the most potent mutagens found in bracken fern, the environmental cofactor in BPV-4-associated carcinogenesis of the upper alimentary canal of cattle. Our results point to quercetin as the probable in vivo cocarcinogen synergizing with BPV-4 in malignant progression. 相似文献
992.
993.
Axotomy-induced expression of calcium-activated chloride current in subpopulations of mouse dorsal root ganglion neurons 总被引:2,自引:0,他引:2
André S Boukhaddaoui H Campo B Al-Jumaily M Mayeux V Greuet D Valmier J Scamps F 《Journal of neurophysiology》2003,90(6):3764-3773
Whole cell patch-clamp recordings of calcium-activated chloride current [ICl(Ca)] were made from adult sensory neurons of naive and axotomized mouse L4-L6 lumbar dorsal root ganglia after 1 day of culture in vitro. A basal ICl(Ca) was specifically expressed in a subset of naive medium-diameter neurons (30-40 microm). Prior nerve injury, induced by sciatic nerve transection 5 days before experiments, increased both ICl(Ca) amplitude and its expression in medium-diameter neurons. Moreover, nerve injury also induced ICl(Ca) expression in a new subpopulation of neurons, the large-diameter neurons (40-50 microm). Small-diameter neurons (inferior to 30 microm) never expressed ICl(Ca). Regulated ICl(Ca) expression was strongly correlated with injury-induced regenerative growth of sensory neurons in vitro and nerve regeneration in vivo. Cell culture on a substrate not permissive for growth, D,L-polyornithine, prevented both elongation growth and ICl(Ca) expression in axotomized neurons. Regenerative growth and the induction of ICl(Ca) expression take place 2 days after injury, peak after 5 days of conditioning in vivo, slowly declining thereafter to control values. The selective expression of ICl(Ca) within medium- and large-diameter neurons conditioned for rapid, efficient growth suggests that these channels play a specific role in postinjury behavior of sensory neuron subpopulations such as neuropathic pain and/or axonal regeneration. 相似文献
994.
Kristen Wigby Monia Hammer Mari Tokita Priyanka Patel Marilyn C. Jones Austin Larson Frances Velez Bartolomei Natalie Dykzeul Anne Slavotinek Tiffany Yip Sara Bandres-Ciga Brittany N. Simpson Kristen Suhrie Suma Shankar Regan Veith Jennifer Bragg Cynthia Powell Stephen F. Kingsmore David Dimmock Jill Maron Jonathan Davis Miguel Del Campo 《American journal of medical genetics. Part A》2023,191(4):930-940
Increasing use of unbiased genomic sequencing in critically ill infants can expand understanding of rare diseases such as Kabuki syndrome (KS). Infants diagnosed with KS through genome-wide sequencing performed during the initial hospitalization underwent retrospective review of medical records. Human phenotype ontology terms used in genomic analysis were aggregated and analyzed. Clinicians were surveyed regarding changes in management and other care changes. Fifteen infants met inclusion criteria. KS was not suspected prior to genomic sequencing. Variants were classified as Pathogenic (n = 10) or Likely Pathogenic (n = 5) by American College of Medical Genetics and Genomics Guidelines. Fourteen variants were de novo (KMT2D, n = 12, KDM6A, n = 2). One infant inherited a likely pathogenic variant in KMT2D from an affected father. Frequent findings involved cardiovascular (14/15) and renal (7/15) systems, with palatal defects also identified (6/15). Three infants had non-immune hydrops. No minor anomalies were universally documented; ear anomalies, micrognathia, redundant nuchal skin, and hypoplastic nails were common. Changes in management were reported in 14 infants. Early use of unbiased genome-wide sequencing enabled a molecular diagnosis prior to clinical recognition including infants with atypical or rarely reported features of KS while also expanding the phenotypic spectrum of this rare disorder. 相似文献
995.
Autosomal recessive retinitis pigmentosa and cone-rod dystrophy caused by splice site mutations in the Stargardt's disease gene ABCR 总被引:12,自引:2,他引:12
Cremers FP; van de Pol DJ; van Driel M; den Hollander AI; van Haren FJ; Knoers NV; Tijmes N; Bergen AA; Rohrschneider K; Blankenagel A; Pinckers AJ; Deutman AF; Hoyng CB 《Human molecular genetics》1998,7(3):355-362
Ophthalmological and molecular genetic studies were performed in a
consanguineous family with individuals showing either retinitis pigmentosa
(RP) or cone-rod dystrophy (CRD). Assuming pseudodominant (recessive)
inheritance of allelic defects, linkage analysis positioned the causal gene
at 1p21-p13 (lod score 4.22), a genomic segment known to harbor the ABCR
gene involved in Stargardt's disease (STGD) and age- related macular
degeneration (AMD). We completed the exon-intron structure of the ABCR gene
and detected a severe homozygous 5[prime] splice site mutation,
IVS30+1G->T, in the four RP patients. The five CRD patients in this
family are compound heterozygotes for the IVS30+1G- >T mutation and a
5[prime] splice site mutation in intron 40 (IVS40+5G- >A). Both splice
site mutations were found heterozygously in two unrelated STGD patients,
but not in 100 control individuals. In these patients the second mutation
was either a missense mutation or unknown. Since thus far no STGD patients
have been reported to carry two ABCR null alleles and taking into account
that the RP phenotype is more severe than the STGD phenotype, we
hypothesize that the intron 30 splice site mutation represents a true null
allele. Since the intron 30 mutation is found heterozygously in the CRD
patients, the IVS40+5G->A mutation probably renders the exon 40 5[prime]
splice site partially functional. These results show that mutations in the
ABCR gene not only result in STGD and AMD, but can also cause autosomal
recessive RP and CRD. Since the heterozygote frequency for ABCR mutations
is estimated at 0.02, mutations in ABCR might be an important cause of
autosomal recessive and sporadic forms of RP and CRD.
相似文献
996.
Transvaginal hydrolaparoscopy as an outpatient procedure for infertility investigation 总被引:10,自引:7,他引:10
A new technique called transvaginal hydrolaparoscopy is described for the
exploration of the tubo-ovarian structures in infertile patients without
obvious pelvic pathology. It aims to be an acceptable alternative to
diagnostic laparoscopy, a standard but not innocuous procedure which
infrequently reveals pathology in the asymptomatic patient. Transvaginal
hydrolaparoscopy copy is performed under local anaesthesia using a small
diameter optic with the patient in the dorsal position. Cavity distension
is achieved with normal saline. Transvaginal hydrolaparoscopy does not
provide the familiar and panoramic view of the pelvis given by laparoscopy,
but it does have several advantages. These include accurate and atraumatic
inspection of adnexal structures without manipulation, with the opportunity
to perform dye hydrotubation and salpingoscopy. The risks of a general
anaesthetic are avoided, and there is less risk of trauma to major vessels.
The high patient acceptability makes transvaginal hydrolaparoscopy suitable
as an early stage procedure in the investigation of infertility and as a
repeat or second look procedure. Minor operative procedures such as biopsy
and adhesiolysis can also be performed. In patients with obvious pelvic
pathology, diagnostic laparoscopy will obviously remain the procedure of
choice. Transvaginal hydrolaparoscopy deserves full evaluation of its
accuracy, risks and benefits before it can be accepted as a new first line
technique in gynaecological practice.
相似文献
997.
998.
Tarek El-Toukhy Rudi Campo Sesh Kamal Sunkara Yacoub Khalaf Arri Coomarasamy 《Reproductive health》2009,6(1):20
Background
The success rate of IVF treatment is low. A recent systematic review and meta-analysis found that the outcome of IVF treatment could be improved in patients who have experienced recurrent implantation failure if an outpatient hysteroscopy (OH) is performed before starting the new treatment cycle. However, the trials were of variable quality, leading to a call for a large and high-quality randomised trial. This protocol describes a multi-centre randomised controlled trial to test the hypothesis that performing an OH prior to starting an IVF cycle improves the live birth rate of the subsequent IVF cycle in women who have experienced two to four failed IVF cycles. 相似文献999.
Shelly Campo PhD Natoshia M. Askelson MPH PhD Erica L. Spies MS Mary Losch PhD 《Women & health》2013,53(3):279-296
Despite high rates of unintended pregnancy among women aged 18 to 30 years, little research has been conducted to understand the factors associated with their contraceptive use. Eighteen focus groups were conducted with young adult women (N = 106) who were mostly white, non-Hispanic. Results suggested that contraceptive use was negatively affected by low contraceptive knowledge; use of alcohol; a lack of planning for sex; a misperception of the likelihood of pregnancy; forgetting to use contraceptives; and concerns about side effects, cost, and confidentiality. Women liked the peace of mind that using contraceptives gave them and the benefits of regular periods from some hormonal methods. Implications for reducing unintended pregnancies through interventions are offered. 相似文献
1000.
Mohr U Dasenbrock C Tillmann T Kohler M Kamino K Hagemann G Morawietz G Campo E Cazorla M Fernandez P Hernandez L Cardesa A Tomatis L 《Carcinogenesis》1999,20(2):325-332
A lifetime experiment using 4279 CBA/J mice was carried out to investigate whether the pre-conceptual exposure of sperm cells to X-ray radiation or urethane would result in an increased cancer risk in the untreated progeny, and/or increased susceptibility to cancer following exposure to a promoting agent. The study consisted of four main groups, namely a control group (saline), a urethane group (1 mg/g body wt) and two X-ray radiation groups (1 Gy, 2 Gy). At 1, 3 and 9 weeks after treatment, the males of these four parental groups were mated with untreated virgin females. The offspring of each parental group was divided into two subgroups: one received s.c. urethane (0.1 mg/g body wt once) as a promoter, the other saline, at the age of 6 weeks. All animals were evaluated for the occurrence of tumours. K-ras oncogene and p53 tumour suppressor gene mutations were investigated in frozen lung tumour samples. The female offspring of male parents exposed to X-rays 1 week before their mating showed a trend towards a higher tumour incidence of the haematopoietic system than the F1 controls. In addition, a higher percentage of bronchioloalveolar adenocarcinomas in male offspring born to irradiated paternals mated 1 week after X-ray treatment points to a plausible increased sensitivity of post-meiotic germ cell stages towards transgenerational carcinogenic effects. On the other hand, no increased tumour incidence and malignancy were observed in the offspring born to irradiated paternals mated 3 and 9 weeks after X-ray treatment. Paternal urethane treatment 1, 3 and 9 weeks prior to conception did not result in significantly altered incidence or malignancy of tumours of the lung, liver and haematopoietic tissue in the offspring. K-ras mutations increased during tumour progression from bronchioloalveolar hyperplasia to adenoma. Codon 61 K-ras mutations were more frequent in lung tumours of urethane-promoted progeny from irradiated parents than from control parents. P53 mutations were absent from these lung alterations. 相似文献