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排序方式: 共有859条查询结果,搜索用时 15 毫秒
31.
(接上期472页)达那唑:是一种作用较弱的雄激素,口服剂量为每次200mg,每天2~4次(每天10~15 mg/kg).57例脾切除术后的ITP患者中,反应率为60%~67%(血小板>50×109/L,持续2个月以上).老年女性和脾切后的患者效果最好.氨苯砜:是一种中等强度的肾上腺皮质激素类药物,常以每次75~100 mg、每天1次口服.对一线肾上腺皮质激素治疗无反应的患者,氨苯砜可使脾切除术推迟32个月以上(证据水平Ⅱb).然而,脾切除术后患者对该药的反应率较低. 相似文献
32.
Obesity in children may cause overt clinical disease in childhood. The complex endocrine and metabolic changes of obesity and insulin resistance in adolescents result in hyperinsulinemia, dyslipidemia, hypertension, steatohepatitis, glucose intolerance, type 2 diabetes, acanthosis nigricans and ovarian hyperandrogenemia, commonly known as polycystic ovarian syndrome (PCOS). Type 2 diabetes and PCOS in adolescents are new endocrine diseases in this age group that require unique approaches to diagnosis and treatment. The direct correlation between duration of disease and control of the disease, and subsequent long term complications of these two diseases, predict serious morbidity in young adult life for the affected adolescents. Pediatricians have an important role in the prevention, diagnosis and treatment of obesity, insulin resistance syndrome, type 2 diabetes and PCOS. 相似文献
33.
Esaki Muthu Shankar Ramachandran Vignesh Kailapuri G Murugavel Pachamuthu Balakrishnan Ramalingam Sekar Charmaine AC Lloyd Suniti Solomon Nagalingeswaran Kumarasamy 《AIDS research and therapy》2007,4(1):1-7
Background
CD4+ T lymphocyte (CD4) cell count testing is the standard method for determining eligibility for antiretroviral therapy (ART), but is not widely available in sub-Saharan Africa. Total lymphocyte counts (TLCs) have not proven sufficiently accurate in identifying subjects with low CD4 counts. We developed clinical algorithms using TLCs, hemoglobin (Hb), and body mass index (BMI) to identify patients who require ART. 相似文献34.
The GAP-related domain of tuberin, the product of the TSC2 gene, is a target for missense mutations in tuberous sclerosis 总被引:5,自引:0,他引:5
Maheshwar MM; Cheadle JP; Jones AC; Myring J; Fryer AE; Harris PC; Sampson JR 《Human molecular genetics》1997,6(11):1991-1996
Tuberous sclerosis is an autosomal dominant trait in which the
dysregulation of cellular proliferation and differentiation results in the
development of hamartomatous growths in many organs. The TSC2 gene is one
of two genes determining tuberous sclerosis. Inactivating germline
mutations of TSC2 in patients with tuberous sclerosis and somatic loss of
heterozygosity at the TSC2 locus in the associated hamartomas indicate that
TSC2 functions as a tumour suppressor gene and that loss of function is
critical to expression of the tuberous sclerosis phenotype. The TSC2
product, tuberin, has a region of homology with the GTPase activating
protein rap1GAP and stimulates the GTPase activity of rap1a and rab5a in
vitro. Here we show that the region of homology between tuberin and human
rap1GAP and the murine GAP mSpa1 is more extensive than previously reported
and spans approximately 160 amino acid residues encoded within exons 34-38
of the TSC2 gene. Single strand conformation polymorphism analysis of these
exons in 173 unrelated patients with tuberous sclerosis and direct
sequencing of variant conformers together with study of additional family
members enabled characterisation of disease associated mutations in 14
cases. Missense mutations, which occurred in exons 36, 37 and 38 were
identified in eight cases, four of whom shared the same recurrent change
P1675L. Each of the five different missense mutations identified was shown
to occur de novo in at least one sporadic case of tuberous sclerosis. The
high proportion of missense mutations detected in the region of the TSC2
gene encoding the GAP-related domain supports its key role in the
regulation of cellular growth.
相似文献
35.
Novero V; Camus M; Tournaye H; Smitz J; Verheyen G; Joris H; Derde MP; Van Steirteghem AC; Devroey P 《Human reproduction (Oxford, England)》1997,12(1):59-63
Serum follicle stimulating hormone (FSH) is routinely measured when
evaluating the infertile male for intracytoplasmic sperm injection (ICSI).
However, among the sperm parameters, only its relationship with sperm
concentration is well documented. Few investigations concern the
relationship between FSH and sperm motility and morphology, and the results
of ICSI. A retrospective study of 316 couples who underwent ICSI was
carried out to determine the relationships between serum FSH concentrations
in the male and (i) standard sperm parameters_(concentration, motility and
morphology) and (ii) fertilization, cleavage, pregnancy and implantation
rates after ICSI. There was an inverse correlation with sperm concentration
and total motility but no relationship was found with progressive motility
and sperm morphology. Neither was any relationship found between serum FSH
and fertilization, cleavage, pregnancy and implantation rates, and the
results of ICSI. These findings suggest the need to review the routine
measurement of serum FSH in the infertile male when ICSI is the planned
treatment procedure.
相似文献
36.
Viability of partially damaged human embryos after cryopreservation 总被引:10,自引:13,他引:10
Van den Abbeel E; Camus M; Van Waesberghe L; Devroey P; Van Steirteghem AC 《Human reproduction (Oxford, England)》1997,12(9):2006-2010
In our centre, embryos are judged to have survived cryopreservation if at
least half of the initial number of blastomeres remain intact. Therefore
both fully intact and partially damaged embryos are transferred. The aim of
this study was to investigate the viability of partially damaged human
embryos after cryopreservation. We retrospectively analysed the
implantation and in-vivo development of embryos which were either fully
intact or had lost some blastomeres after cryopreservation. Oocytes were
collected following stimulation with the gonadotrophin-releasing hormone
(GnRH)-agonist Buserelin and human menopausal gonadotrophin. Supernumerary
multicellular embryos with not more than 20% of their volume filled with
anucleate fragments were frozen on day 2 or day 3 of the cycle using a slow
cooling procedure with dimethylsulphoxide as the cryoprotectant. Following
slow thawing, 431 fully intact embryos were transferred in 314 embryo
transfer procedures and 488 partially damaged embryos were transferred in
327 such procedures. The percentage of gestational sacs with fetal
heartbeat obtained after transfer of fully intact embryos was almost three
times higher than that after transfer of partially damaged embryos (11.4
versus 3.5%). Forty-five children (birth rate 10% per embryo transfer) were
born after transfer of fully intact embryos and 14 after transfer of
embryos from which some blastomeres had been lost following
cryopreservation. In conclusion, although children have been delivered
after transfer of partially damaged embryos, the aim of a cryopreservation
programme must be to obtain fully intact embryos after thawing.
相似文献
37.
Berry V; Ionides AC; Moore AT; Plant C; Bhattacharya SS; Shiels A 《Human molecular genetics》1996,5(3):415-419
Inherited cataract is a clinically and genetically heterogeneous disease.
Here we report the identification of a new locus for an autosomal dominant
anterior polar cataract on the short arm of chromosome 17. To map this new
locus we performed genetic linkage analysis with microsatellite markers in
a four-generation pedigree. After exclusion of seven candidate loci for
cataract, we obtained significant positive LOD scores for markers D17S849
(Z = 4.01 / theta = 0.05) and D17S796 (Z = 4.17 / theta = 0.05). Multipoint
analysis gave a maximum LOD score of 5.2 (theta max = 0.06) between these
two markers. From haplotype analysis, the cataract locus lies in the 13 cM
interval between markers D17S849 and D17S796. This study provides the first
genetic mapping of an autosomal dominant anterior polar cataract.
相似文献
38.
Background
Genetic polymorphisms of the TCF7L2 gene are strongly associated with large increments in type 2 diabetes risk in different populations worldwide. In this study, we aimed to confirm the effect of the TCF7L2 polymorphism rs7903146 on diabetes risk in a Brazilian population and to assess the use of this genetic marker in improving diabetes risk prediction in the general population. 相似文献39.
Helicobacter pylori infection stimulates plasminogen activator inhibitor 1 production by gastric epithelial cells 下载免费PDF全文
Keates AC Tummala S Peek RM Csizmadia E Kunzli B Becker K Correa P Romero-Gallo J Piazuelo MB Sheth S Kelly CP Robson SC Keates S 《Infection and immunity》2008,76(9):3992-3999
Chronic infection with the gastric pathogen Helicobacter pylori significantly increases the risk of developing atrophic gastritis, peptic ulcer disease, and gastric adenocarcinoma. H. pylori strains that possess the cag pathogenicity island, which translocates CagA into the host cells, augment these risks. The aim of this study was to determine the molecular mechanisms through which H. pylori upregulates the expression of plasminogen activator inhibitor 1 (PAI-1), a member of the urokinase activator system that is involved in tumor metastasis and angiogenesis. Levels of PAI-1 mRNA and protein were examined in tissues from H. pylori-infected patients and in vitro using AGS gastric epithelial cells. In vitro, cells were infected with toxigenic cag-positive or nontoxigenic cag-negative strains of H. pylori or isogenic mutants. The amount of PAI-1 secretion was measured by enzyme-linked immunosorbent assay, and mRNA levels were determined using real-time PCR. The regulation of PAI-1 was examined using the extracellular signal-regulated kinase 1/2 (ERK1/2) inhibitor and small interfering RNA. Analysis of human biopsy samples revealed an increase in both PAI-1 mRNA and protein levels in patients with H. pylori gastritis compared to those of uninfected controls. Infection of AGS cells with H. pylori significantly increased PAI-1 mRNA expression and the secretion of PAI-1 protein. Moreover, PAI-1 mRNA and protein production was more pronounced when AGS cells were infected by H. pylori strains carrying a functional cag secretion system than when cells were infected by strains lacking this system. PAI-1 secretion was also reduced when cells were infected with either cagE-negative or cagA-negative mutants. The ectopic overexpression of CagA significantly increased the levels of PAI-1 mRNA and protein, whereas blockade of the ERK1/2 pathway inhibited H. pylori-mediated PAI-1 upregulation. These findings suggest that the upregulation of PAI-1 in H. pylori-infected gastric epithelial cells may contribute to the carcinogenic process. 相似文献
40.
AC Winter K Berger JE Buring & T Kurth 《Cephalalgia : an international journal of headache》2009,29(2):269-278
We evaluated the association of body mass index (BMI) with migraine and migraine specifics in a cross-sectional study of 63 467 women aged ≥ 45 years, of whom 12 613 (19.9%) reported any history of migraine and 9195 had active migraine. Compared with women without migraine and a BMI < 23 kg/m2 , women with a BMI ≥ 35 kg/m2 had adjusted odds ratios (ORs) (95% confidence intervals) of 1.03 (0.95, 1.12) for any history of migraine. Findings were similar for active migraineurs. Women with a BMI of ≥ 35 kg/m2 had increased risk for low and high migraine frequency, with the highest estimate for women who reported daily migraine. Compared with women with the lowest associated risk (migraine frequency < 6 times/year; BMI between 27.0 and 29.9 kg/m2 ), women with a BMI ≥ 35 kg/m2 had an OR of daily migraine of 3.11 (1.12, 8.67). Among the women with active migraine, a BMI ≥ 35 kg/m2 was associated with increased risk of phonophobia and photophobia and decreased risk of a unilateral pain characteristic and migraine aura. Our data confirm previous findings that the association between BMI with migraine is limited to migraine frequency and specific migraine features. 相似文献