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51.
We aimed to assess the knowledge of Turkish physicians about sleep disorders and the attitude of the physicians towards sleep medicine. We prepared a 24-item-questionnaire, 7 of the questions were about the attitudes of the physicians and 17 of them were about the knowledge of the physicians. We applied the questionnaire in all university and educational hospitals in Ankara, which is the capital city and the second largest city of Turkey. Two-hundred-fifteen medical doctors from 5 different specialties accepted to answer the questionnaire, and 168 (78%) of them completed the questionnaire. 47% of the physicians rated themselves as they had little knowledge about sleep disorders, and 45% as they had enough knowledge about sleep disorders, however, the overall score was not high. They answered only 45.3% of the questions correctly. In the light of this survey, we concluded that medical education on sleep disorders should be extended both in length and in content to improve the quality of sleep disorders medicine in Turkey.  相似文献   
52.
Phospholipids located in the cellular membrane play a critical role in the fluid-mosaic model of membrane structure and membrane function. Evidence is mounting for the role of abnormal phospholipid metabolism in some neuropsychiatric disorders including schizophrenia. As an important essential fatty acid (EFA), omega-3 (omega-3) fatty acid series are found in large amounts in fish oil. The aim of this experimental study was to assess the changes of some of the oxidant and antioxidant parameters in the hypothalamus of rats fed with omega-3 EFA diet (0.4 g/kg/day) for 30 days. Eight control rats and nine rats fed with omega-3 were decapitated under ether anesthesia, and hypothalamus was removed immediately. Malondialdehyde (MDA) and nitric oxide (NO) levels as well as superoxide dismutase (SOD) and xanthine oxidase (XO) enzyme activities in the hypothalamus were measured. SOD activity was significantly decreased in omega-3 EFA treated group compared to control group (p < 0.014). Tissue MDA and NO levels were also decreased in omega-3 EFA treated group compared to control rats (p < 0.0001). Xanthine oxidase activity was found to be increased in omega-3 EFA treated rats when compared to the control group (p < 0.0001). Taken together, this preliminary animal study provides strong support for a therapeutic effect of omega-3 EFA in some neuropsychiatric disorders in which reactive oxygen species (ROS) are recently accused to be an important physiopathogenetic factor.  相似文献   
53.
OBJECTIVE: To determine the feasibility of using calculated nucleated red blood cell (RBC) counts from histologic placental slides to predict newborn nucleated RBC counts. METHODS: This retrospective study compared absolute nucleated RBC counts from 24 newborns, diagnosed with fetal distress in labor, with counts calculated from their histologic placental slides. A simple linear regression model was tested with newborn nucleated RBC counts as the dependent variable and calculated placental nucleated RBC counts as the independent variable. RESULTS: The mean +/- standard deviation newborn nucleated RBC count was 4.81 x 10(9) +/- 5.46 x 10(9)/L compared with 1.37 x 10(9) +/- 1.78 x 10(9)/L calculated from placental sections. These data were normalized by logarithmic transformation. A significant linear regression was obtained, r(2) = 0.74, P <.001. The prediction equation obtained was natural logarithm (newborn nucleated RBC count) is equal to 1.002 x natural logarithm (placental nucleated RBC count) + 1.173. CONCLUSION: It is feasible to calculate nucleated RBC counts from histologic slides of the placenta that are predictive of newborn nucleated RBC counts. Further work on more homogeneous groups of subjects is necessary to increase the precision of the method. The placenta could serve as a surrogate source for newborn whole blood nucleated RBC counts around the time of birth.  相似文献   
54.
BACKGROUND: Acute bacterial rhinosinusitis (ABRS) is a common illness that is routinely managed by physicians from several different specialties. However, the actual diagnostic and treatment preferences of physicians from these different specialties are not known. OBJECTIVE: To determine whether the radiographic evaluation and management of community-acquired ABRS differs according to medical specialty. DESIGN, SETTING, AND PARTICIPANTS: Randomized survey of 450 board-certified physicians in the United States from family medicine, general internal medicine, and otolaryngology. MAIN OUTCOME MEASURES: Responding physicians' use of diagnostic radiography as well as choice and duration of antimicrobial and adjunctive treatments of ABRS. RESULTS: Otolaryngologists were more likely to use supportive diagnostic radiography (P =.04). They were also more likely to treat patients with adjunctive therapy, such as topical decongestants (P =.01), guaifenesin (P =.01), and saline nasal irrigation (P =.01), in addition to antibiotics. Otolaryngologists prescribed more medications to treat patients with ABRS than primary care physicians (P =.01). There were no significant differences in diagnosis and management by family physicians and general internists. CONCLUSIONS: Otolaryngologists use more health care resources to diagnose and treat ABRS than primary care physicians despite an absence of evidence that such tests and treatments lead to better outcomes. Otolaryngologists typically treat a patient population with a higher prevalence of ABRS and frequently see referred patients with recurrent acute sinusitis and chronic rhinosinusitis, which may explain their tendency to treat patients more aggressively. Nevertheless, these survey results illustrate a lack of consensus within the medical community regarding the evaluation and management of community-acquired ABRS, suggesting that widely accepted evidence-based practice guidelines need to be developed.  相似文献   
55.
We report a case in which an intrarenal arteriovenous fistula caused the nutcracker effect. Color Doppler sonography of the left renal artery showed a peak systolic velocity of 150 cm/second and renoaortic ratio of 2.1. The left renal vein was significantly dilated, and the adjacent renal artery was kinked. A stenosis in the left renal vein at the aorto-mesenteric bifurcation was demonstrated, with a maximum velocity of 201 cm/second. Renal Doppler evaluation showed an area of high-velocity, low-resistance arterial flow consistent with an arteriovenous fistula in the inferior half of the left kidney. Angiography confirmed the fistula. The fistula was successfully occluded by coil embolization. Follow-up sonography showed almost complete obliteration of the fistula, regression of the renal vein dilatation, and a reduction in renal venous and arterial flow velocities. Given the reversibility of the fistula's effects, we suggest the term "pseudonutcracker effect" to describe this case.  相似文献   
56.
Various classifications have been used for congenital anomalies of the Müllerian system. We report a case of a previously unknown anomaly of the uterus, and propose its possible embryological causes. The patient presented with primary amenorrhoea and infertility, and during laparoscopy three distinct uterine horns were observed. The tubes were connected to the two most lateral horns, each juxtaposed to a normal ovary. The middle horn had a seemingly normal attachment to the right uterosacral ligament, whereas its attachment to the left uterosacral ligament appeared attenuated and less normal. Furthermore, the right horn was immediately attached to the middle horn, whereas the left horn was, like its ipsilateral uterosacral ligament, attached to the middle horn by a more attenuated, stretched fibrous bridge. Only the middle horn, with its uterosacral ligaments, had an attached, although obstructed, cervix. Ultrasonographic examination revealed no endometrium echogeneity in any of these uterine bulbs. No etiologic factors were noted in the patient's history; her mother denied known ingestion of estrogens or other drugs while carrying her daughter. The pathogenesis of this anomaly cannot be clearly defined, but may involve sequential embryological errors of duplication of the Müllerian tracts, failure of fusion of each set of the Müllerian tracts with expected failed canalization of each tract and, finally, agenesis of the medial horn of the left duplicated tracts.  相似文献   
57.
58.
The goal of this retrospective study was to evaluate factors that increase the risk of bowel necrosis and document the outcome of bowel resection in patients with strangulated hernias. We identified 102 patients (60 men, 42 women) who underwent surgical treatment for an incarcerated hernia at the Kartal Education and Research Hospital Emergency Unit between April 1997 and April 2001. Patients in group 1 required intestinal resection (n = 16), and patients in group 2 did not (n = 86). The median age of the patients was 53 years (range 3–96). Demographic and surgical data were obtained from the patients charts and compared between the two groups. Women required bowel resections more often than men (p < 0.05). Patients older than 65 years and those with femoral or epigastric hernias required resection more often than patients younger than 65 years and those with inguinal, umbilical, or incisional hernias (p < 0.05 for all). Group 1 patients had a longer hospitalization and experienced more overall complications and wound infections than group 2 (p < 0.05 for all). In conclusion, incarcerated hernias are more common in men, but intestinal resection is required more often in women. The risk of intestinal resection is higher for patients with femoral hernias and those older than 65 years. Patients who undergo intestinal resection have a higher overall complication rate related to wound infections but not an increased risk of other complications or mortality.This study was presented at the 5th European Congress of Trauma and Emergency Surgery, Istanbul, Turkey, October 2002.  相似文献   
59.
Desmoplastic small round cell tumor (DSRCT) correspond to a recent clinicopathological entity, individualized in 1989 into the group of tumors with small round cells. This pathology puts ethiopathogenic, diagnostic, therapeutic and prognosis problems. Indeed, the ethiopathogenic is still unknown, diagnosis is asserted only by immuno-histochimic and cytogenetic study because of the big number of differential diagnoses and the anatomopathologic polymorphism. Its treatment is not well codified and its outcome remains dark in spite of therapeutic progress. The objective of this work is to report a personal observation of a DSRCT and to proceed to a review of the literature to clarify the epidemiological, clinical, paraclinical and therapeutic aspects of this rare tumor.  相似文献   
60.
We have recently reported that flavonoids of cocoa inhibit the mammalian 15-lipoxygenase-1-a catalyst of enzymatic lipid peroxidation. To elucidate the structure-activity relationship of the inhibitory effect, we investigated the effects of 18 selected flavonoids of variable structure on pure rabbit reticulocyte and soybean 15-lipoxygenases using linoleic acid as substrate. Moreover, the inhibition by quercetin was studied in detail to gain insight into the mode of action. Quercetin was found to modulate the time-course of the reaction of both lipoxygenases by three distinct effects: (i) prolongation of the lag period, (ii) rapid decrease in the initial rate after the lag phase was overcome, (iii) time-dependent inactivation of the enzyme during reaction but not in the absence of substrate. A comparison of the IC(50) for the rapid inhibition of rabbit reticulocyte 15-lipoxygenase-1 revealed that (i) the presence of a hydroxyl group in the flavonoid molecule is not essential, (ii) a catechol arrangement reinforces the inhibitory effect, (iii) in the presence of a catechol arrangement the inhibitory potency inversely correlates with the number of hydroxyl groups, (iv) a 2,3-double bond in the C ring strengthens the inhibitory effect. The flavone luteolin turned out to be the most potent inhibitor of the mammalian enzyme with an IC(50) of 0.6 microM followed by baicalein (1 microM) and fisetin (1.5 microM).  相似文献   
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