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81.
Mapping of the gene for cleidocranial dysplasia in the historical Cape Town (Arnold) kindred and evidence for locus homogeneity. 下载免费PDF全文
R S Ramesar J Greenberg R Martin R Goliath S Bardien S Mundlos P Beighton 《Journal of medical genetics》1996,33(6):511-514
Cleidocranial dysplasia (CCD) is an autosomal dominant disorder, features of which include a patient anterior fontanelle, a bulging calvarium, hypoplasia or aplasia of the clavicles, a wide public symphysis, dental anomalies, vertebral malformation, and short stature. The Cape Town kindred which is under our genetic management was originally described more than four decades ago and now consists of more than 1000 people. Following reports of rearrangements on chromosomes 6 and 8 in people with CCD, we have carried out linkage analyses between highly information microsatellite dinucleotide repeat markers in the rearranged regions and the disorder in a branch of this South African CCD kindred, consisting of 38 subjects, 18 of whom are affected. Maximum lod scores (at theta = 0.00) of 7.14 (for marker D6S459), 4.32 (TCTE), 4.99 (D6S452), 5.97 (D6S269), and 3.95 (D6S465) confirm linkage of the disorder to the short arm of chromosome 6. Our data indicate that the CCD gene is located within a minimal region of approximately 10 cM flanked by the marker D6S451 distally and D6S466 proximally. This information is vital towards isolating and characterising the gene for CCD, and is being used to construct a physical map of 6p21.1-6p21.3. More importantly, mapping of the locus in the South African kindred of mixed ancestry, in which the "founder" of the disorder was of Chinese origin, suggests that a single locus is responsible for classic CCD. 相似文献
82.
Lamont RE Loredo-Osti J Roslin NM Mauthe J Coghlan G Nylen E Frappier D Innes AM Lemire EG Lowry RB Greenberg CR Triggs-Raine BL Morgan K Wrogemann K Fujiwara TM Zelinski T 《American journal of medical genetics. Part A》2005,(2):136-143
Bowen-Conradi syndrome (BCS) is a lethal autosomal recessive disorder with an estimated incidence of 1 in 355 live births in the Hutterite population. A few cases have been reported in other populations. Here, we report the results of a genome-wide scan and fine mapping of the BCS locus in Hutterite families. By linkage and haplotype analysis the BCS locus was mapped to a 3.5 cM segment (1.9 Mbp) in chromosome region 12p13.3 bounded by F8VWF and D12S397. When genealogical relationships among the families were taken into account in the linkage analysis, the evidence for linkage was stronger and the number of potentially linked regions was reduced to one. Under the assumption that all the Hutterite patients were identical by descent for a disease-causing mutation, haplotype analysis was used to infer likely historical recombinants and thereby narrow the candidate region to a chromosomal segment shared in common by all the affected children. This study also demonstrates that BCS and cerebro-oculo-facial-skeletal syndrome (COFS) are genetically distinct. 相似文献
83.
Localization of tissue transglutaminase in human carotid and coronary artery atherosclerosis: implications for plaque stability and progression 总被引:3,自引:0,他引:3
Haroon ZA Wannenburg T Gupta M Greenberg CS Wallin R Sane DC 《Laboratory investigation; a journal of technical methods and pathology》2001,81(1):83-93
Although atherosclerosis progresses in an indolent state for decades, the rupture of plaques creates acute ischemic syndromes that may culminate in myocardial infarction and stroke. Mechanical forces and matrix metalloproteinase activity initiate plaque rupture, whereas tissue inhibitors of metalloproteinases have an important (albeit indirect) role in plaque stabilization. In this paper, an enzyme that could directly stabilize the plaque is described. Tissue transglutaminase (TG) catalyzes the formation of epsilon(gamma-glutamyl)lysine isopeptide bonds that are resistant to enzymatic, mechanical, and chemical degradation. We performed immunohistochemistry for TG in atherosclerotic human coronary and carotid arteries. TG was most prominent along the luminal endothelium and in the medium of the vessels with a distribution mirroring that of smooth muscle cells. Variable, often prominent, immunoreactivity for TG was also seen in the intima, especially in regions with significant neovascularization. Additionally, TG was detected in fibrous caps and near the "shoulder regions" of some plaques. A monoclonal antibody to the transglutaminase product epsilon(gamma-glutamyl)lysine isopeptide demonstrated co-localization with TG antigen. Transglutaminase activity was found in 6 of 14 coronary artery atherectomy samples. Cross-linking of TG substrates such as fibrinogen, fibronectin, vitronectin, collagen type I, and protease inhibitors stabilized the plaque. Furthermore, the activation of transforming growth factor-beta-1 by TG might be an additional mechanism for the promotion of plaque stabilization and progression by increasing the synthesis of extracellular matrix components. 相似文献
84.
Psychological and neuropsychological aspects of COPD 总被引:2,自引:0,他引:2
A review of the literature dealing with the effects of chronic obstructive pulmonary disease (COPD) on psychological and neuropsychological functioning indicates that significant emotional and adaptive deficits characterize this patient population. Psychiatric consultation can provide valuable assistance to the primary care physician by reducing emotional distress and correcting dysfunctional attitudes and beliefs. Neuropsychological assessment can elucidate an individual's neurobehavioral resources and deficits. 相似文献
85.
Stroke in rodents is associated with increased neurogenesis and the migration of newborn neurons to sites of brain ischemia, where they may participate in repair and recovery. To determine if neurogenesis following stroke yields functional new neurons, we labeled neuronal precursors in the mouse subventricular zone (SVZ) with a lentivirus-green fluorescent protein vector, produced stroke by occluding the middle cerebral artery, and detected newborn neurons 8 weeks later by fluorescence microscopy. Patch-clamp studies on fluorescent neurons in the cortical region surrounding infarction showed tetrodotoxin-sensitive Na+ action potentials and spontaneous excitatory post-synaptic currents, suggesting that ischemia led to functional neurogenesis with synaptic integration. These findings support the hypothesis that enhancing endogenous neurogenesis after stroke might have therapeutic benefit. 相似文献
86.
Gonadotrophin-releasing hormone agonist dose-dependency of pituitary desensitization during controlled ovarian hyperstimulation in IVF 总被引:2,自引:2,他引:2
Janssens RM; Vermeiden JP; Lambalk CB; Schats R; Schoemaker J 《Human reproduction (Oxford, England)》1998,13(9):2386-2391
The aim of this study was to find the minimal effective daily s.c. dose of
the gonadotrophin-releasing hormone (GnRH) agonist, triptorelin acetate,
that suppresses the GnRH-induced release of luteinizing hormone (LH) at
time of human chorionic gonadotrophin (HCG) injection and thereby prevents
spontaneous LH surges during in-vitro fertilization (IVF) stimulation
cycles. Therefore, a double-blind, prospective and randomized titration
study was performed. A total of 48 IVF patients were divided into four
groups of 12 patients. Each group received a different dose of triptorelin
acetate, namely 5, 15, 50 or 100 microg s.c. daily. Standard ovarian
stimulation was carried out using urinary follicle stimulating hormone
(FSH) preparations. A 500 microg GnRH test was performed 90 min before the
HCG injection in order to measure the degree of pituitary desensitization.
Spontaneous LH surges were not detected in any of the groups, although
three patients in the 5 microg group had ovulated at the time of ovum
retrieval. The pituitary LH response to the GnRH test at time of HCG,
expressed as area under the curve (AUC), appeared to be dose-dependent.
Thus, a daily s.c. dose of 100 microg triptorelin acetate appears to be too
high, since adequate desensitization of the pituitary (i.e. no spontaneous
LH surge) can be achieved with doses as low as 15 and 50 microg.
相似文献
87.
B lymphocytes secreting IgG linked to latent transforming growth factor- beta prevent primary cytolytic T lymphocyte responses 总被引:3,自引:0,他引:3
B lymphocytes secreting IgG linked to latent transforming growth factor
(TGF)-beta (IgG-TGF-beta) prevent cytolytic T lymphocyte (CTL) responses to
unrelated antigens in mixed lymphocyte cultures (MLC) so long as resting
resident macrophages and functional Fc receptors are present. This was
shown using IgG-secreting plaque-forming cells (PFC) to sheep erythrocytes
(SRBC) obtained from popliteal lymph nodes of mice injected repeatedly in
foot pads with SRBC. Remarkably, as few as approximately 300 PFC prevented
CTL responses of 5 x 10(5) normal syngeneic spleen cells in MLC.
Supranatants of short-term cultures of PFC also prevented CTL responses,
and suppression was prevented by eliminating or dissociating IgG and
TGF-beta present in supranatants or by antibody against active TGF-beta.
Furthermore, the latency- associated peptide of latent TGF-beta was
detected in approximately 10% of foci of IgG captured from single PFC,
indicating that at least some B lymphocytes secrete IgG-TGF-beta as a
complex. Resting resident macrophages (which do not produce latent
TGF-beta) and functional Fc receptors were required for suppression,
consistent with idea that IgG- TGF-beta is taken up through Fc receptors
for IgG and that active TGF- beta, cleaved from latent TGF-beta of the
complex, is delivered directly to potentially responding CTL. If CTL
responses in man are similarly regulated by B lymphocytes, then an ongoing
B cell response in patients with chronic viral infections or bearing
immunogenic cancers may prevent effective therapeutic vaccination.
相似文献
88.
Enhancement of antigen incorporation and infectivity of cell cultures by human rotavirus. 总被引:2,自引:0,他引:2 下载免费PDF全文
B D Schoub A R Kalica H B Greenberg D M Bertran M M Sereno R G Wyatt R M Chanock A Z Kapikian 《Journal of clinical microbiology》1979,9(4):488-492
Infection of cell cultures with human rotavirus preparations was attempted and the effects of trypsin and low-speed centrifugation on antigen incorporation, as demonstrated by immunofluorescence and radioimmunoassay, were determined. In addition, the effect of viral aggregation on antigen incorporation was investigated by filtering viral preparations. Four strains of human rotavirus were employed, and the results were compared to those obtained with two tissue culture-adapted animal rotaviruses. Centrifugation and trypsin appeared to have little or no effect on infectivity of the tissue culture-adapted (simian rotavirus) or -adaptable (Nebraska calf diarrhea virus) strains, whereas centrifugation and viral aggregation appeared to be essential for the human viruses. In addition, trypsin enhanced antigen incorporation of the human strains to some extent. Infectivity for cell cultures and in vitro human rotavirus protein formation was demonstrated by [35S]methionine incorporation, and the specificity of this human viral protein was established by radio-immunoprecipitation. 相似文献
89.
The lung in cystic fibrosis. A quantitative study including prevalence of pathologic findings among different age groups. 总被引:12,自引:0,他引:12
The autopsies of 82 patients with cystic fibrosis were reviewed with respect to pathologic changes in the lungs and their respective prevalence among different age groups. Although bronchitis, mucopurulent plugging, and bronchopneumonia were almost universally present among children of all ages, epithelial metaplasia and bronchiectasis were rarer among infants and progressively more prevalent in older age groups. Emphysema was absent in patients under two years of age and affected 11 per cent of the patients two to six years of age and 40 per cent of the patients older than six years, but was never of a severe degree by the point count method. Pulmonary hemorrhage, although uncommon, was usually associated with prominent arterial vessels in walls of bronchiectatic airways. Quantitative assessment of bronchial glands revealed Reid indices significantly higher in patients with cystic fibrosis when compared to noncystic fibrosis patients, but there was no increase in these indices with the age of the patients. Glandular hypertrophy, predominance of mucous acini within glands, and goblet cell hyperplasia of the bronchial mucosa all suggest an explanation for the copious mucous secretion of patients with cystic fibrosis. However, it was not possible to ascertain whether these findings reflect a general exocrine defect of such patients or whether they were merely a response to chronic airway infection, even though the latter is a more plausible assumption. 相似文献
90.
Weekly intramuscular injections of slow-release, depot methyl prednisolone to 15 adult Dutch rabbits did not bring about an increase in the volume of their carotid bodies. However, they caused swelling of chief cells with discrete areas of pallor in the cytoplasm. Factors responsible for these changes appear to be increased storage of catecholamines and an increased number of swollen mitochondria. 相似文献