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101.
Dissection of the carotid artery can occur intracranially or extracranially, although dissections tend to affect extracranial segments of the arteries much more commonly than intracranial segments. Carotid artery dissection (CAD) is most common in middle-aged women. Although not completely known, the main risk factors related to carotid artery dissection are genetic and environmental factors, traumatic events, cervical manipulation, migraine, recent infections, hyperhomocysteinemia, and hereditary connective tissue disorders. Although some cases of bilateral internal CAD have been reported, spontaneous bilateral dissections are rare. Prolonged hoarseness is usually due to using the voice either too much, too loudly, or improperly over an extended period of time. Disorders leading to dysphagia may affect the oral, pharyngeal, or esophageal phases of swallowing. In this study we report on a patient with bilateral CAD who presented to our clinic with dysphagia and hoarseness.  相似文献   
102.
Primary hemangiopericytoma of the rib is extremely rare and only a few cases have been reported. A 62-yr-old man presented with an aching chest pain and dyspnea. Thoracic computed tomography revealed a homogenous mass expanding the right seventh rib. A diagnosis of hemangiopericytoma was established by percutaneous needle biopsy. Preoperative embolization of the feeding vessels of the tumor was performed in order to prevent perioperative bleeding. There was no significant bleeding during the surgery, where complete resection of the tumor with 7th to 9th ribs with a surgical margin of 5 cm was performed. Postoperative course was uneventful and there has been no recurrence for thirteen months. To our knowledge, there has been no report to apply a preoperative embolization of a primary hemangiopericytoma of the rib.  相似文献   
103.
Retroperitoneal cystic lymphangioma is a rare congenital malformation. The majority of lymphangiomas are present at birth and nearly all present before the age of two years. We report a case of giant cystic retroperitoneal lymphangioma in a patient who first presented with symptoms at the age of 7, underwent surgery, and who then suffered a recurrent mass 11 years later.  相似文献   
104.
105.
Hemodynamic forces play an important role in sculpting the embryonic heart and its valves. Alteration of blood flow patterns through the hearts of embryonic animal models lead to malformations that resemble some clinical congenital heart defects, but the precise mechanisms are poorly understood. Quantitative understanding of the local fluid forces acting in the heart has been elusive because of the extremely small and rapidly changing anatomy. In this study, we combine multiple imaging modalities with computational simulation to rigorously quantify the hemodynamic environment within the developing outflow tract (OFT) and its eventual aortic and pulmonary valves. In vivo Doppler ultrasound generated velocity profiles were applied to Micro-Computed Tomography generated 3D OFT lumen geometries from Hamburger-Hamilton (HH) stage 16-30 chick embryos. Computational fluid dynamics simulation initial conditions were iterated until local flow profiles converged with in vivo Doppler flow measurements. Results suggested that flow in the early tubular OFT (HH16 and HH23) was best approximated by Poiseuille flow, while later embryonic OFT septation (HH27, HH30) was mimicked by plug flow conditions. Peak wall shear stress (WSS) values increased from 18.16 dynes/cm(2) at HH16 to 671.24?dynes/cm(2) at HH30. Spatiotemporally averaged WSS values also showed a monotonic increase from 3.03 dynes/cm(2) at HH16 to 136.50?dynes/cm(2) at HH30. Simulated velocity streamlines in the early heart suggest a lack of mixing, which differed from classical ink injections. Changes in local flow patterns preceded and correlated with key morphogenetic events such as OFT septation and valve formation. This novel method to quantify local dynamic hemodynamics parameters affords insight into sculpting role of blood flow in the embryonic heart and provides a quantitative baseline dataset for future research.  相似文献   
106.
Qiu Q  Li R  Jiang P  Xue L  Lu Y  Song Y  Han J  Lu Z  Zhi S  Mo JQ  Guan MX 《Human mutation》2012,33(8):1285-1293
We report here the clinical, genetic, molecular, and biochemical evaluations in two Han Chinese families with maternally inherited hypertension. Fourteen of 20 adult matrilineal relatives of these families exhibited a wide range of severity in hypertension, while none of offspring of affected fathers had hypertension. The age-at-onset of hypertension in matrilineal relatives varied from 37 years to 83 years, with an average of 55 and 66 years, respectively. Mutational analysis of their mitochondrial genomes identified the m.4353T>C mutation in the tRNA, in conjunction with the known m.593C>T mutation in the tRNA(Phe) and m.5553C>T mutation in the tRNA(Trp). Northern analysis revealed that m.4353T>C, m.593C>T and m.5553C>T mutations caused ~66%, 65%, and 12% reductions in the steady-state level of tRNA(Gln), tRNA(Phe) and tRNA(Trp), respectively. An in vivo protein labeling analysis showed ~35% reduction in the rate of mitochondrial translation in cells carrying these tRNA mutations. Impaired mitochondrial translation is apparently a primary contributor to the reduced rates of overall respiratory capacity, malate/glutamate-promoted respiration, succinate/glycerol-3-phosphate-promoted respiration, or N,N,N',N'-tetramethyl-p-phenylenediamine/ascorbate-promoted respiration and the increasing level of reactive oxygen species in the cells carrying these mtDNA mutations. These data demonstrate that mitochondrial dysfunction caused by mitochondrial tRNA mutations is associated with essential hypertension in these families.  相似文献   
107.
Many clinically relevant congenital malformations arise during mid to late embryonic stages. This period is challenging to image quantitatively in live embryos, necessitating the use of multiple specimens with increased experimental variability. Here we establish X‐ray and blood‐pool computed tomography (CT) contrast agent toxicity and teratogenesis thresholds for 3D Micro‐CT imaging of live avian embryos. Day 4 chick embryos micro‐injected with Visipaque? (VP) developed for an additional 6 days without defect. X‐ray radiation up to 798 mGy was nontoxic. Peak average contrast of 1,060 HU occurred within 1 hr of imaging at 50 μm resolution. VP‐enhanced contrast persisted past 24 hr with delayed accumulation in the allantois. Regional volumes of VP‐injected embryos were statistically identical to those of fixed embryos perfused with osmium tetroxide. We further quantified longitudinal volumetric morphogenesis of the allantois over 30 hr. These results demonstrate the safety and efficacy of contrast enhanced quantitative micro‐CT imaging for live embryos. Developmental Dynamics 240:1949–1957, 2011. © 2011 Wiley‐Liss, Inc.  相似文献   
108.

Purpose

Almost 50 % of the patients experience moderate-to-severe pain during endometrial biopsy. The study aimed to examine the effectiveness of intrauterine lidocaine for relieving pain during endometrial biopsy.

Methods

A randomised trial was conducted in 120 patients undergoing endometrial biopsy. Sixty-seven women were assigned to the paracervical block group and 53 were assigned to the intrauterine lidocaine group. The main outcome measure was pain intensity, measured using the visual analogue scale, during and after the procedure.

Results

The groups were similar with regard to age, body mass index, gravidity, total number of previous vaginal deliveries, menopausal status, and uterine depth. The pain scores immediately after the procedure were similar in the groups (p = 0.079). However, the pain scores 30 min after the procedure were significantly lower in the intrauterine group than in the paracervical group (p = 0.0001).

Conclusions

Compared to paracervical block, intrauterine lidocaine may be the preferred anaesthesia for endometrial biopsy, and it does not cause any serious complications.  相似文献   
109.
Because slime-forming microorganisms are the major causative agents of graft infections, we aimed to investigate bacterial adherence in slime-forming and nonslime-forming Staphylococcus aureus and to determine the role of neuraminidase (NANase) on adherence to gelatin-impregnated polyester fiber graft fabric. An in vitro model was developed to quantitatively measure bacterial adherence to the surface of the graft. The grafts were divided into two groups – those colonized with slime-forming S. aureus and those colonized with nonslime-forming S. aureus. The grafts were put into sterile tubes and human plasma was instilled and incubated at 37°C to perform fibrin deposition on the grafts. After 48 h of incubation, grafts were drained and inoculated with slime-forming or nonslime-forming S. aureus in triptic soy broth in the presence or absence of NANase. Following 36 h of incubation at 36°C, grafts were vortexed and cultured to perform a colony count. Bacterial counts were expressed as total colony-forming units per square centimeter of graft. Slime-forming S. aureus had greater affinity with the graft compared with nonslime-forming S. aureus (P < 0.05). The adherence of slime-forming S. aureus was impaired by NANase treatment (P < 0.001) but NANase treatment of nonslime-forming S. aureus did not change the adherence to the graft (P > 0.05). These results show that slime plays an important role in the pathogenesis of vascular graft infection. Adherence of slime-forming S. aureus can be decreased by NANase treatment. This may have implications for the development of neuraminidase-embedded vascular grafts to diminish biomaterial-related infections.  相似文献   
110.
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