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991.
BACKGROUND: The objective of the present study was to assess the accuracy of an air tonometry device in vivo within a wide range of regional carbon dioxide tension (PrCO2) values by using saline tonometry as the standard and to investigate the possibilities to monitor perfusion of the intestine by tonometry in the intraperitoneal cavity. METHODS: Piglets were anesthetized and mechanically ventilated. A pair of tonometry catheters was placed in the sigmoid colon, while another pair was placed intraperitoneally in the right lower quadrant of the abdomen. Air tonometric regional PCO2 (aPrCO2) was measured every 15 min intraperitoneally and every 20 min in the sigmoid colon. Saline tonometric measurements were made every 30 min and steady-state values (ssPrCO2) were derived. Hypoperfusion shock was induced by graded constriction of the aorta. Endotoxin shock was induced by administration of lipopolysaccharide (LPS). RESULTS: The obtained average PrCO2 (=matched (aPrCO2+ ssPrCO2)/2) values ranged from 5.1 kPa to 14.7 kPa. Regional air PCO2 (aPrCO2) and steady-state saline PCO2 (ssPrCO2) exhibited a strong positive linear relationship (r=0.959). The 95% confidence interval of the mean of dPrCO2 (=aPrCO2-ssPrCO2) was 0.31-0.46 kPa. Intraperitoneal tonometric PrCO2 was lower than intraluminal PrCO2 in the sigmoid colon, and was also more sensitive to circulatory changes than sigmoid colon PrCO2. CONCLUSION: The regional air PCO2 (aPrCO2) showed good agreement with the steady-state saline regional PCO2 (ssPrCO2). Intraperitoneal measurements may be an alternative method of monitoring intestinal perfusion after abdominal surgery.  相似文献   
992.
Abstract: For accurate assessment of the response to primary chemotherapy (PCT) for locally advanced breast cancer, we measured reduction in total tumor volume (TTV) by using three‐dimensional magnetic resonance imaging (3D MRI), and examined the relationship between this reduction and patient prognosis. Fifty‐one patients with locally advanced breast cancer were treated with four cycles of docetaxel (60 mg/m2) before surgery. Tumor size was measured with calipers, ultrasonography (US) and conventional two‐dimensional (2D) MRI before and after chemotherapy. TTV was measured with 3D MRI. These and other clinicopathological parameters were statistically analyzed to determine the prognosis for the patients. Median follow‐up time was 46 months (1–64 months). Of the 51 patients, 25 developed distant recurrences. Patients whose TTV decreased by 75% or more after PCT showed significantly better prognosis than others, while tumor size measured with calipers, US and 2D MRI showed no significant relationship with patient prognosis. Of the clinicopathological parameters, only reduction in TTV and histological grade showed a significant association with distant recurrence‐free survival (p = 0.03 and 0.02, log‐rank test), while stepwise multivariate Cox’s proportional hazards analysis identified TTV as the strongest independent prognostic factor. Reduction in TTV measured with 3D MRI can be a useful prognostic factor for patients with locally advanced breast cancer treated with PCT.  相似文献   
993.
An investigation was made of 5-fluorouracil metabolism in rat liver by 19F MRS. Fluoronucleotide synthesis increased markedly with liver injury and accelerated with uracil treatment, indicating that 19F MRS may serve as a new method for evaluating liver viability.  相似文献   
994.
995.
996.
Splenic cellularity during the recovery phase after 400-R irradiation was evaluated in mice, in which the level of prostaglandin was regulated by indomethacin and exogenous prostaglandin E2, following sublethal irradiation. Two weeks after irradiation, administration to these mice of indomethacin, an inhibitor of prostaglandin synthesis, augmented the recovery of all nucleated spleen cell populations, whereas the thymus was drastically depopulated. This treatment had little effect upon the total number of bone marrow cells but inversed the ratio of PNA+/PNA- cells. Cell transfer experiments using heavily irradiated mice as recipients showed that the stem cell proliferation was positively affected by indomethacin treatment in the bone marrow rather than in the spleen. These results suggest that cell migration from primary lymphoid organs, particularly from the bone marrow to the spleen, is regulated by a prostaglandin-mediated system and that a prostaglandin E2 synthesis inhibition would have a positive effect on the restoration of peripheral nucleated cells following irradiation.  相似文献   
997.
Ischemic colitis following aortic reconstruction for abdominal aortic aneurysm was discussed. The low morbidity rate of postoperative abdominal symptom was recognized significantly when meandering mesenteric artery (MMA) was shown clearly in angiography before surgery. When inferior mesenteric artery (IMA) was patent before surgery, furthermore when IMA was not reconstructed, it is necessary for preventing postoperative ischemic colitis that mean IMA/systemic pressure ratio is above 0.5 or 0.6.  相似文献   
998.
Little is known about the effect of normal-range blood pressure (BP) on cognitive function. In previous studies investigating the relationship between BP and cognitive function in elderly subjects, underlying cerebrovascular damage has complicated the interpretation of results. To reveal the relationship between BP levels that were within an absolutely normal range and cognitive function, we examined cognitive function in normotensive, healthy middle-aged women. BP levels were measured on three separate occasions at 1-month intervals, and the subjects exhibiting normotension (< 140/90 mmHg) throughout the evaluation period were recruited as normotensive subjects. Cognitive function was assessed using subtests of the Wechsler Adult Intelligence Scale-Revised. The study demonstrated that, among the subtests examined, the scores on the Digit Symbol Test, an index of psychomotor performance, had a significant correlation with normotensive-range systolic blood pressure (SBP) (r=-0.51, p<0.05); this relation was negative-that is, higher but still normal-range SBP levels were associated with impaired Digit Symbol Test scores. In addition, the relationship adjusted by age and educational level was also significant (partial correlation = -0.56, p<0.05). In contrast, diastolic BP was not related to the Digit Symbol Test (r = -0.33, p = 0.13). Furthermore, the Digit Symbol Test was not influenced by blood glucose or serum cholesterol levels. These findings suggested that, even within the normotensive range, lower levels of SBP might be protective against impairment of psychomotor speed in middle-aged women.  相似文献   
999.
A case of immotile cilia syndrome accompanied by retinitis pigmentosa is reported. This syndrome involves congenital ciliary ultrastructural abnormality. A 27-year-old male complained of repeated pneumonia, sinusitis, and middle otitis. In addition, he had sperm motor insufficiency and electron microscopic finding of cilia led to the diagnosis of the present syndrome. Both fundi presented remarkable degeneration of retinal pigment epithelium and choroid and marked arterial narrowing. Constriction of the visual field and extinguished ERG were also noted. Abnormality of cilia of the retinal pigment epithelium was suggested. It was proposed that retinitis pigmentosa may be caused by abnormal cilia of the retinal pigment epithelium.  相似文献   
1000.
Peritoneal hyperthermia may have a role in limiting serosal metastatic disease. When applied to the peritoneal cavity immediately after surgery, it is important to know the optimum temperature, and to investigate the subsequent healing of intestinal anastomoses. To study the first problem, local hyperthermia was applied to the intestinal loop of rats for 30 min. Treatment at 46.0 degrees C or 45.0 degrees C resulted in 100 per cent and 90 per cent mortality respectively, but 100 per cent survival was obtained at 44.0 degrees C. To study the second problem rats with intestinal anastomoses were studied in three groups: group A, local hyperthermia (44.0 degrees C x 30 min) applied to the intestinal loop containing the anastomosis; group B, local hyperthermia (44.0 degrees C x 30 min) applied using saline supplemented with mytomycin C (10 mg/l); group C (controls) no thermal treatment was applied. Anastomotic healing was assessed by breaking strength and histological examination. On the third day after operation, the breaking strength of anastomoses decreased to the lowest values in each group, but no statistically significant differences were noted. On the seventh and 14th day, increased resistance to breaking developed in all three groups and was greatest in the thermally treated groups. Histological findings supported these results. Local hyperthermia up to 44.0 degrees C x 30 min had no adverse effects on the healing of intestinal anastomoses.  相似文献   
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