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991.
Silvia Masnada Daniele Gibelli Claudia Dolci Valentina De Giorgis Annalisa Cappella Pierangelo Veggiotti Chiarella Sforza The Italian Aicardi Study Group 《American journal of medical genetics. Part A》2020,182(10):2325-2332
Aicardi syndrome (AIC) is a rare congenital neurodevelopmental disorder of unknown etiology, that affects almost exclusively females, originally characterized by corpus callosum agenesis, chorioretinal lacunae, and infantile spasms. The current diagnostic criteria also include qualitative facial features (prominent premaxilla, upturned nasal tip, decreased nasal bridge angle, sparse lateral eyebrows, and microphthalmia) that still need quantification. A three‐dimensional (3D) photogrammetric assessment of 11 Italian females, age 7–32 years, who satisfied AIC criteria, was performed. Linear distances and angles were computed from soft‐tissue facial landmarks coordinates. The z‐score values were calculated using data of 850 healthy reference females matched for age and compared by Mann–Whitney test (p < .01). Patients showed a shorter philtrum and right side orbital height (mean z‐scores: ?1.7, ?0.9), shorter superior, middle, and inferior facial depths (mean z‐scores: ?1.3, ?2.2, ?2.3), and a smaller length of mandibular ramus (mean z‐score: ?2.1); conversely, they showed larger nasal and lower facial widths, and lower facial convexity (mean z‐scores: 1.7, 1.4, 2.4). The inclinations of the orbit versus the true horizontal were increased bilaterally (mean z‐scores: 1.8, 1.1). Some common facial abnormalities were quantified in AIC patients using a noninvasive instrument. They may help clinicians in performing a definite AIC diagnosis in atypical or doubt cases. 相似文献
992.
Marieke C. J. Dekker Adnan M. Sadiq Mubashir A. Jusabani Vivian J. Mdavire Frank Baas David H. Morton Ben C. J. Hamel 《American journal of medical genetics. Part A》2019,179(10):2034-2038
We report an African infant with Ellis‐van Creveld (EVC) syndrome. EVC syndrome is a chondral and ectodermal dysplasia with autosomal recessive transmission. The baby presented with polydactyly, short limbs and atrioventricular septal defect, but was withdrawn from clinical follow up for the first year of life. Initial hematological abnormalities could not be explained and normalized later. EVC syndrome was confirmed by genetic analysis that showed two pathogenic mutations in the EVC2 gene, c.653_654del, p.Val218Glyfs*12 in exon 5, and c.2710C>T, p.Gln904* in exon 16. The variant c.653_654del; p.Val218Glyfs*12 in exon 5 has not been described before. Our review of medical literature suggested this is the first molecularly confirmed case of EVC syndrome in sub‐Saharan Africa. 相似文献
993.
Popov AV Sitnik NA Savvateeva-Popova EV Wolf R Heisenberg M 《Neuroscience and behavioral physiology》2003,33(1):53-65
The question of the roles of the two main parts of the insect brain, the mushroom bodies and the central complex, in controlling motor coordination and triggering a variety of behavioral programs, including sound production, remains controversial. With the aim of improving our understanding of this question, we studied the parameters of songs used by five-day-old males during courtship for fertilized wild-type females (Canton-S, C-S) over 5-min periods at 25°C; males were of two wild-type Drosophila Melanogaster lines (Berlin and C-S). Berlin males lacking mushroom bodies because of treatment with hydroxyurea during development (chemical removal of the mushroom bodies) were used, along with two mutants with defects in the mushroom bodies (mbm
1 and mud
1), two mutants with defects in the central complex (ccb
KS127 and cex
KS181), and mutant cxb
N71 with defects in both the mushroom bodies and the central complex. The experiments reported here showed that courtship songs in males lacking mushroom bodies were virtually identical to those of wild-type males. The main parameters of pulsatile song in mutants mbm
1 and mud
1 (interpulse interval and train duration) were insignificantly different from those of the songs of wild-type flies, though the stability of the pulse oscillator was the same. Flies of these lines were no different from wild-type flies in terms of courtship success (percentage of copulating pairs in 10-min tests). Conversely, the songs of mutants with defects in the central complex differed from those of wild-type males. Firstly, there was degradation of the stability of the pulse oscillator and interpulse intervals were very variable. In addition, pulses were often significantly longer and appeared multicyclic, as in the well-known cacophony mutant, while the mean train duration was significantly shorter. Males of the line cex
KS181 usually courted very intensely, though abnormal sounds were generally emitted. Mutants cex
KS181 and ccb
KS127 were significantly less successful in courtship than wild-type flies. These data show that the central complex appears to play a very important role in controlling song, while the mushroom bodies are not related to this function. 相似文献
994.
Reza-Albarran AA Gomez-Perez FJ Lopez JC Herrera M Gamboa-Dominguez A Keirns C Aranda A Rull JA 《Endocrine pathology》1999,10(3):251-257
Pigmented nodular cortical hyperplasia, a rare cause of Cushing’s syndrome, is characterized by resistance to inhibition with
dexamethasone and normal sized adrenal glands with multiple, small pigmented nodules. The disorder may be a component of a
syndrome inherited as an autosomal dominant pattern that includes intra- and extracardiac myxomas, lentiginous lesions, blue
nevi, other functional endocrine tumors, and peripheral nerve tumors (Carney’s complex).
We report a patient in whom bilateral myelolipomas were found, in addition to the usual features of this complex. A 29-yr-old
man was admitted to the hospital for Cushing’s syndrome of probably more than 15 yr duration. Physical examination showed
diffuse facial hyperchromatic macules, 0.2–0.5 cm, predominantly around the lips and on the palmar surfaces of the fingers.
Results with dexamethasone suppression nocturnal testing (1 and 8 mg) were compatible with an adrenal adenoma. The computed
tomography (CT) of the sella turcica was normal. Adrenal CT showed a tumor in the left gland with a double component: one
solid and another suggestive of fat, consistent with an angiomyelolipoma. Following 5 wk treatment with ketoconazole, 800
mg per day po, serum cortisol decreased to 5.9 μg/dL, morning and evening, respectively.
Bilateral adrenalectomy was performed. Pathologic examination revealed pigmented nodular cortical hypersplasia and a dominant
myelolipoma in the left adrenal. A microscopic myelolipoma was identified in the right adrenal.
An echocardiogram showed a mass on the posterior wall of the left ventricle which was a myxoma. Study of the patient's family
disclosed two sisters with facial lentigines. Echocardiograms were performed on all available first degree relatives: all
were normal. Nocturnal inhibition with dexamethasone revealed that one of the patient’s sisters with lentigines also had hypercortisolism.
Myelolipoma has been reported in association to Cushing syndrome in humans and experimentally after pituitary extracts in
animals. The relationship between this finding and the Carney’s complex remain elusive. 相似文献
995.
目的 研究前交通动脉复合体(antcrior communicating artery complex,ACoAC)及其毗邻结构的显微解剖特点,为该区域的手术提供显微解剖数据,方法在10例(20侧)成人头颅标本上,分别在不同的视角下对ACoAC及其发出的穿支动脉进行解剖观察;取出整脑后对ACoAC各部分直径、长度进行测量、拍照,所得数据用SPNSS10.0软件进行统计分析,结果10例(20侧半球)共有20支大脑前动脉。双侧ACA—A1段长度和直径比较未见显著性差异.ACA-A1段后下壁发出许多穿支血管。前交通动脉形态变异很多均发出穿支血管,分别供应下丘脑、视交叉、胼胝体膝部等。Hcubner回返动脉是ACoAC发出的最粗大的穿支血管,其起源、行程变异很大。ACoAC发出很多供应视交又及视神经的穿支血管.他们大多来自ACA—A1段。结论 ①双侧ACA-A1段发育多不对称,可能与前交通动脉瘤的发生有关。ACA—A1段均发出重要的穿支血管.手术时应仔细加以分辨、保护..ACoA形态变异很大,但与ACA-A1段发育不良关东不大,②Heubner回返动脉起源和形态堑异很大。③OC和ON的血液供应有上、下两个起源。 相似文献
996.
J. Duffin J. van Alphen 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》1995,103(2):251-255
Ipsilateral and contralateral pairs of augmenting expiratory neurons were recorded simultaneously from the Bötzinger complex using glass-coated tungsten microelectrodes in pentobarbitone-anaesthetized cats. The neurons were identified both by firing pattern and by antidromic activation from the contralateral site of the dorsal respiratory group. Cross-correlation histograms of the extracellularly recorded action potentials were calculated in order to detect short time-scale synchronizations of firing indicative of synaptic connections between the neurons. The cross-correlation histograms for 40 ipsilateral pairs of neurons less than 1 mm apart showed eight (20%) narrow troughs (mean half-amplitude width ±SD, 1.1±0.37 ms) at short latencies (mean latency±SD, 1.0±0.35 ms) suggestive of monosynaptic inhibition. These included two cross-correlation histograms which showed troughs on both sides of time zero, indicating a mutual inhibition. For another four pairs of neurons (10%), a central broad peak suggestive of common activation due to either excitation or release from inhibition was evident. Contralateral pairs of expiratory neurons of the Bötzinger complex were examined in a similar manner. The cross-correlation histograms for 43 pairs of neurons showed five (12%) narrow troughs (mean half-amplitude width±SD, 1.2±0.67 ms) at short latencies (mean latency±SD, 2.7±1.47 ms) suggestive of monosynaptic inhibition. These included one cross-correlation histogram which showed troughs (one not statistically significant) on both sides of time zero, indicating a mutual inhibition. For another two pairs of neurons (4.6%) a central, broad peak suggestive of common activation due to either excitation or release from inhibition was evident. We conclude that inhibitory interconnections exist between augmenting expiratory neurons of the Bötzinger complex ipsilaterally and contralaterally. These connections may synchronize the expiratory burst of activity within this population and assist in the patterning of the burst. 相似文献
997.
H. W. L. Ziegler-Heitbrock D. Stachel T. Schlunk L. Gürtler W. Schramm M. Fröschl J. R. Bogner G. Riethmüller 《Journal of clinical immunology》1988,8(6):473-478
In a selected group of human immunodeficiency virus (HIV)-infected patients we confirm the expansion of a CD8+ T-lymphocyte subset, i.e., the CD8+/Leu7+ cells, which account for 30% of the lymphocytes, compared to 3% in the control donors. In addition, a CD8+ T-lymphocyte subset that coexpresses class II (DR) antigens, i.e., CD8+/DR+ cells, is also increased from 1.5% in controls to 27% in the HIV-infected patients. Using three-color immunofluorescence and flow cytometry we can demonstrate that the CD8+/Leu7+ and the CD8+/class II+ cells are not distinct but overlapping subsets. In the HIV-infected patients 42% of the CD8+/Leu7+ cells were strongly positive for class II and these CD8+/Leu7+/class II+ cells accounted for 13% of all lymphocytes. These findings indicate that the expanded CD8+/Leu7+ cells are activated and hence might be actively involved in immune defense in acquired immune deficiency syndrome (AIDS). 相似文献
998.
999.
Ethan A. Carver Kathleen F. Oram Thomas Gridley 《Anatomical record (Hoboken, N.J. : 2007)》2002,268(2):90-92
Saethre‐Chotzen syndrome is a common autosomal dominant form of craniosynostosis, the premature fusion of the sutures of the calvarial bones of the skull. Most Saethre‐Chotzen syndrome cases are caused by haploinsufficiency for the TWIST gene. Mice heterozygous for a null mutation of the Twist gene replicate certain features of Saethre‐Chotzen syndrome, but have not been reported to exhibit craniosynostosis. We demonstrate that Twist heterozygous mice exhibit fusions of the coronal suture and other cranial suture abnormalities, indicating that Twist heterozygous mice constitute a better animal model for Saethre‐Chotzen syndrome than was previously appreciated. Anat Rec 268:90–92, 2002. © 2002 Wiley‐Liss, Inc. 相似文献
1000.
Chen CD Chen HF Lu HF Chen SU Ho HN Yang YS 《Human reproduction (Oxford, England)》2000,15(5):1037-1042
The aim of this study was to examine the role of serum and follicular fluid pro-inflammatory cytokines and vascular endothelial growth factor (VEGF) in the prediction of ovarian hyperstimulation syndrome (OHSS). A total of 156 consecutive women undergoing in-vitro fertilization were recruited. The study group comprised 12 women who subsequently developed moderate (n = 7) or severe (n = 5) OHSS. The two control groups were comprised of a randomized selection of 12 high-risk and 12 low-risk women in whom OHSS did not develop. Serum was collected on days of human chorionic gonadotrophin, oocyte retrieval, and embryo transfer. Serum and follicular fluid concentrations of interleukin (IL)-6, IL-8, tumour necrosis factor-alpha (TNF-alpha), and VEGF were measured. Follicular fluid IL-6 concentrations at the time of oocyte retrieval and serum IL-8 concentrations at the time of embryo transfer were significantly higher in the OHSS compared to the two control groups (P = 0.026 and P = 0.017 respectively). Serum concentrations of TNF-alpha and VEGF showed no statistically significant difference between the OHSS group and the controls at any studied time point. This study suggests that follicular fluid IL-6 concentrations at the time of oocyte retrieval and serum IL-8 concentrations on the day of embryo transfer may serve as early predictors for this syndrome. 相似文献