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101.
An 11-year-old girl presented with headache of 3 months' duration. There was bilateral disc edema. The cerebrospinal fluid pressure was 50 cm of water with normal cerebrospinal fluid cytology and biochemistry. She developed severe headache (different and disabling), dizziness, vomiting, and backache on sitting up 6 hours after lumbar puncture, and lying supine relieved all of her symptoms. Intravenous fluids, analgesics, and complete bed rest did not relieve her symptoms over the next 72 hours. She was completely relieved of her symptoms on receiving two tablets of Caffergot containing 200 mg of caffeine and 2 mg of ergotamine 72 hours after lumbar puncture. The symptoms recurred 48 hours later, and a repeat dose of Caffergot was required. Magnetic resonance imaging (MRI) done 96 hours after lumbar puncture revealed the entire dura overlying the brain, including the posterior fossa, showing intense enhancement on contrast injection with leak at the lumbar puncture site. Oral caffeine (coffee, three times a day) was advised over 1 week. The patient remained asymptomatic, and a repeat MRI scan after 10 days showed complete clearing of the cerebrospinal fluid leak with no dural enhancement. The syndrome of cerebrospinal fluid hypovolemia following lumbar puncture is reported in a girl with idiopathic intracranial hypertension.  相似文献   
102.
Drug smuggling is prevalent in our society. It is now frequently seen in the emergency room as an acute life-threatening emergency. The following case describes one such patient with an emphasis on the CT findings in these cases. Electronic Publication  相似文献   
103.
Differences in coronary risk factors and coronary heart disease (CHD) prevalence between the Hindus and the Muslims have not been adequately studied. This study aims to determine the prevalence of certain socio-economic and biological coronary risk factors in urban communities and to compare the findings found in the Hindus and the Muslims. The study employed a cross-sectional survey design and stratified random sampling technique consisting of 1,415 males and 797 females. Among males there were 1,092 Hindus (77.2%) and 272 Muslims (19.2%) while in females there were 685 Hindus (85.9%) and 91 Muslims (11.4%). Prevalence of illiteracy and sedentary lifestyle were significantly more in Muslims (p<0.05). Smoking or tobacco use in males was similar but in females it was more in the Hindus. Self-reported diabetes was found in 1.4% Hindu males and in 1.2% Hindu females. No Muslim reported diabetes. Hindu males were significantly taller than Muslims (163.9 +/- 8.3 versus 160.9 +/- 8.9 cm; p < 0.001). In both males and females there was no significant difference in body mass index and obesity. In Hindu males the diastolic BP was significantly greater than in Muslims (81.2 +/- 9.2 versus 79.0 +/- 8.6 mm Hg; p < 0.001); prevalence of hypertension (30.5% versus 25.7%) was also significantly more (p = 0.048). In Hindu females the mean systolic BP was significantly more and there was also difference in hypertension prevalence (35.2% versus 25.3%). CHD prevalence was significantly greater in Hindu males as compared to the Muslims when determined by the presence of either ECG changes alone (4.3% versus 0.7%; p = 0.008) or ECG changes combined with clinical history (7.1% versus 1.8%; p = 0.002). A similar, though not significant, trend was seen in females (ECG changes: 8.9% versus 6.6%, clinical and ECG changes: 10.4% versus 6.6%). The prevalence of CHD is significantly more in Hindu males as compared to the Muslims and is associated with a greater prevalence of diabetes and hypertension.  相似文献   
104.
Nanocrystalline titanium dioxide (nano-TiO(2)) is an important material used in commerce today. When designed appropriately it can generate reactive species (RS) quite efficiently, particularly under ultraviolet (UV) illumination; this feature is exploited in applications ranging from self-cleaning glass to low-cost solar cells. In this study, we characterize the toxicity of this important class of nanomaterials under ambient (e.g., no significant light illumination) conditions in cell culture. Only at relatively high concentrations (100 microg/ml) of nanoscale titania did we observe cytotoxicity and inflammation; these cellular responses exhibited classic dose-response behavior, and the effects increased with time of exposure. The extent to which nanoscale titania affected cellular behavior was not dependent on sample surface area in this study; smaller nanoparticlulate materials had effects comparable to larger nanoparticle materials. What did correlate strongly to cytotoxicity, however, was the phase composition of the nanoscale titania. Anatase TiO(2), for example, was 100 times more toxic than an equivalent sample of rutile TiO(2). The most cytotoxic nanoparticle samples were also the most effective at generating reactive oxygen species; ex vivo RS species generation under UV illumination correlated well with the observed biological response. These data suggest that nano-TiO(2) samples optimized for RS production in photocatalysis are also more likely to generate damaging RS species in cell culture. The result highlights the important role that ex vivo measures of RS production can play in developing screens for cytotoxicity.  相似文献   
105.
The use of Tc-99m sestamibi to localize parathyroid adenomas is well established. Its greatest value is in the detection of adenomas in presurgical candidates to localize one or more adenomas in the parathyroid glands or to identify ectopic parathyroid adenomas. The authors describe a patient who had long-standing hyperparathyroidism with a history of end-stage renal disease, hypertension, and peptic ulcers with gastrointestinal bleeding. The scan showed a large ectopic parathyroid adenoma in the left retrosternocleidomastoid region. At surgery, the adenoma was located between the jugular vein and the carotid artery, within the carotid sheath.  相似文献   
106.
This study was undertaken to test the hypothesis that basal sympathetic activity and sympathetic reactivity to stress are increased in patients with essential hypertension. One hundred and fifteen randomly selected patients with essential hypertension and an equal number of age- and sex-matched normal controls were included in this study. Various parameters, viz., heart rate, respiratory rate, blood pressure, peripheral skin temperature, electromyographic activity of the frontalis muscle, skin conductance (measured by electrodermography), and blood pressure, were measured in the resting state in both groups. These parameters were then measured during the performance of various stressful activities, such as mental arithmetical calculations, thinking of unpleasant thoughts, staring at a fixed point, catching of a dropped object, and reading aloud for 1 min each, and again over a 1-min quiet period following each stressful activity. Changes in various parameters in the two groups were analyzed and compared. Baseline heart rate, respiratory rate, electromyographic activity and peripheral skin temperature were higher-while skin conductance was lower-in the hypertensive group than in the control group. The increases in systolic blood pressure, diastolic blood pressure, heart rate, respiratory rate, electromyographic activity, and peripheral skin temperature in response to stress were greater in hypertensive patients than in controls, while skin conductance showed a higher elevation in controls than in hypertensive patients. In conclusion, sympathetic nervous system activity is increased in patients with essential hypertension. The reduced skin conductance and high peripheral skin temperature in these patients may be due to a possible dermal neurovascular dysfunction.  相似文献   
107.
Efficacy in stimulating adenylyl cyclase (AC) has traditionally been used to distinguish dopamine D1-like receptor agonists from dopamine D2-like receptor agonists. However, there is a limited association between the effects of D1-like agonists in behavioral assays and their effectiveness at stimulating AC. Other second messenger actions might contribute to the behavioral effects of D1-like agonists, as there is evidence for a link to the hydrolysis of phosphoinositide (PI). The present study compared the locomotor stimulant effects of five D1-like receptor agonists having different efficacies in assays of AC and PI activity. All D1-like agonists produced long-lasting biphasic effects on locomotor activity. SKF 38393, the prototypical partial agonist (based on AC activity), produced limited changes in locomotor activity, whereas the partial agonists SKF 75670 and SKF 77434 produced locomotor stimulant effects that were similar to or greater than those of the full efficacy agonists SKF 82958 and SKF 81297. However, there did not appear to be a relationship between maximal behavioral effects and AC stimulation or PI hydrolysis. The results suggest a complex relationship between the behavioral effects of D1-like agonists and their intrinsic efficacies as measured by AC and /or PI stimulation. Although a limited number of compounds were examined, neither second messenger system alone appears to account fully for these behavioral effects. The current classification of D1-like agonists according to their intrinsic efficacies as defined by AC stimulation needs further scrutiny.  相似文献   
108.
Pant R  Yasko AW  Lewis VO  Raymond K  Lin PP 《Cancer》2005,104(1):149-158
BACKGROUND: Chondrosarcoma is the second most common primary sarcoma of bone. It often develops within flat bones, such as the pelvis, ribs, and scapula. In the current study, the authors reviewed the surgical experience and long-term oncologic outcomes of patients with chondrosarcoma arising in the scapula. METHODS: The medical records of 29 consecutive patients with chondrosarcoma of the scapula were reviewed. The patients were treated between 1954 and 1994. All patients had localized disease at the time of presentation. The tumors were classified histologically as Grade 1 (10 patients), Grade 2 (10 patients), Grade 3 (7 patients), dedifferentiated (1 patient), and mesenchymal (1 patient) (using the criteria of Evans et al.). The mean maximal dimension of the tumors was 11 cm. Twenty-five patients underwent limb-sparing surgical resection and 4 patients underwent forequarter amputations. The median follow-up was 13 years (range, 1-35 years). RESULTS: At last follow-up, 22 patients (76%) were free of disease and 7 patients (24%) had died of their disease. Local recurrence occurred in 4 patients at 7 months, 16 months, 40 months, and 43 months, respectively. The local recurrence-free survival rate was 86% at 5 years, 10 years, and 20 years. Disease-specific survival was 83% at 5 years, 74% at 10 years, and 74% at 20 years. Patients who had low-grade chondrosarcomas had better survival compared with patients who had high-grade chondrosarcomas (P = 0.07). CONCLUSIONS: Patients who had localized chondrosarcoma of the scapula had a favorable long-term outcome, most likely due to the unique anatomic features that improved the likelihood of achieving wide surgical margins with limb-sparing surgery, despite the frequent presentation of locally advanced disease.  相似文献   
109.
Tumors of the inferior vena cava are rare, and most of these are leiomyosarcomas. They are most frequent in the sixth decade of life, with a female predominance. We present a 45-year-old male patient with a tumor involving the entire extent of the inferior vena cava. Computerized tomography revealed a heterogeneously enhancing mass with marked expansion of the inferior vena cava with extraluminal extension. Computerized tomography--guided biopsy of the extraluminal component showed features of a fasciculated spindle cell tumor positive for vimentin, smooth muscle actin, and calponin and negative for S-100 antigen. We discuss the clinical presentation imaging findings and review the literature.  相似文献   
110.
Laparoscopic adrenalectomy for pheochromocytoma and laparoscopic dismembered pyeloplasty are both technically difficult procedures. We describe the case of a 61-year-old female patient who presented with a right adrenal pheochromocytoma and bilateral pelvi-ureteric junction obstruction with renal failure who underwent a successful simultaneous transperitoneal laparoscopic adrenalectomy and pyeloplasty.  相似文献   
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