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51.
PURPOSE: To quantitate the effects of a selective cyclooxygenase (COX)-2 inhibitor, NS-398, on porcine and human ureteral contractility in vitro. MATERIALS AND METHODS: This study was performed in 3 distinct groups. In group 1, segments of ureter were obtained from freshly sacrificed domestic swine. Sections were isolated and suspended longitudinally. Twenty-four ureteral segments were treated with either indomethacin (a nonselective COX inhibitor), NS-398 (selective COX-2 inhibitor), or DMSO (control). Spontaneous contractions were then recorded in each group. In group 2, fifteen segments of human ureter were obtained from patients undergoing donor nephrectomy or ureteral reimplantation. Segments were isolated and suspended as above, and treated with either indomethacin, NS-398, or DMSO. In group 3, eighteen sections of human ureter obtained from donor nephrectomy patients were passively sensitized for 20 hours in ragweed allergic donor serum. Ureteral segments were then treated with either indomethacin, NS-398 or DMSO, and then the segments were subsequently exposed to ragweed antigen and contractions were subsequently recorded. RESULTS: In group 1, the average time to 100% inhibition of spontaneous contraction was 48.8 minutes (S.E.M. = 7.9) for indomethacin, 65.7 minutes (S.E.M. 6.7) for NS-398, and beyond 150 minutes for DMSO. The percent reduction was 100% for indomethacin (S.E.M. = 0), 92.5% for NS-398 (S.E.M. 4.9%), and 52.9% for DMSO (s.e.m. = 10.8%). In group 2, the average time to 100% inhibition was 29 minutes (S.E.M. = 10.4) for indomethacin, 21 minutes (S.E.M. 4.8) for NS-398, and beyond 150 minutes for DMSO. The percent reduction was 100% for indomethacin (S.E.M. = 0), 100% (S.E.M. = 0) for NS-398, and 20% (S.E.M. = 12%) for DMSO. In group 3, ragweed sensitized ureters treated with DMSO (control group) contracted an average maximum of 10 times per 5 minutes. Antigen failed to induce contractions of sensitized tissues treated with indomethacin or NS-398. CONCLUSION: A selective COX-2 inhibitor (NS-398) reduces ureteral contractility as effectively as indomethacin (a nonselective COX inhibitor) in both porcine and human ureteral segments in vitro (p <0.05). Selective COX-2 inhibitors may have significant clinical potential in treating renal colic as they cause less gastric ulceration. 相似文献
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Kitagawa H Pringle KC Zuccollo J Koike J Nakada K Ikoma M Seki Y 《Journal of pediatric surgery》2000,35(11):1651-1655
BACKGROUND/PURPOSE: Creating an obstructive uropathy early in glomerulogenesis would produce multicystic dysplastic kidneys (MCDK). Measuring the mean planar area of the glomeruli (GMPA) may clarify the pathogenesis of MCDK. METHODS: Fetal lambs at 60 days' gestation had their left ureter ligated and were delivered by cesarian section at 145 days' gestation. Kidney weight and length were recorded. GMPA in 3 zones (outer, middle, inner) of the sectioned kidney was measured using a computerized planimeter. The obstructed kidneys were compared with contralateral unobstructed kidneys. The unpaired Student's t test was used to determine significance. RESULTS: One ewe miscarried. Four of 5 (80%) 60-day lambs survived. All had dysplastic kidneys. Mean kidney weights were 4.3 +/- 0.84 g in MCDK and 16.8 +/- 3.6 g in controls (P< .05). The GMPA of the outer, middle, and inner zones of the MCDK were 2.7 x 10(-3) mm2, 3.2 x 10(-3) mm2, and 4.0 x 10(-3) mm2, respectively. Controls were 2.8 x 10(-3) mm2, 4.4 x 10(-3) mm2, and 6.0 x 10(-3) mm2. The glomeruli of 60-day fetal kidneys were 3.0 x 10(-3) mm2, 6.1 x 10(-3) mm2, and 11.0 x 10(-3) mm2. MCDK had smaller glomeruli in the inner and middle zones than controls. CONCLUSION: Fetal glomeruli appear to grow from the inner zone of the kidney. Early urinary tract obstruction stops this growth. 相似文献
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Nobuyuki Enomoto Yoshiyuki Takei Kazuyoshi Kon Shunhei Yamashina Satoko Suzuki Kenichi Ikejima Nobuhiro Sato 《Nihon Arukōru Yakubutsu Igakkai zasshi》2005,40(3):213-218
The hepatotoxic effects of alcohol have been described in detail, but factors responsible for its hepatotoxicity have only partially characterized. It now appears that Kupffer cell derived TNF-alpha participates in several aspects of alcoholic liver injury. On the other hand, protease inhibitors have been used successfully for treatment of intractable diseases in which TNF-alpha is involved in the pathogenesis, including ulcerative colitis and Crohn's disease. Here, we will review new evidence for the proposal that serine protease inhibitors prevents alcoholic liver injury via mechanisms dependent on Kupffer cell derived TNF-alpha. 相似文献
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Y. Suzuki M. Urashima Y. Ishibashi M. Abo N. Omura K. Nakada N. Kawasaki K. Eto N. Hanyu K. Yanaga 《European journal of surgical oncology》2005,31(10):1166-1174
AIM: To prove the feasibility of hand-assisted laparoscopic and thoracoscopic surgery (HALTS) for radical esophagectomy with three-field lymphadenectomy to thoracic esophageal cancer. METHODS: Esophagectomy with three-field lymphadenectomy was performed using HALTS in 19 patients with thoracic esophageal cancer without distant metastasis. Five patients had chemo-radiotherapy prior to surgery. RESULTS: All operations were completed successfully without the need for open surgery. Mean surgical time was 476+/-58 min, and mean blood loss during surgery was 343+/-184 mL. All patients started tube feeding and were moved from the intensive care unit to the general surgery ward the day after surgery. Discharge occurred a median of 10 days after surgery. Fifteen patients could return to full time jobs from 8 to 62 days after surgery (median 22 days) and from 1 to 35 days after discharge (median 9 days). Other three could return to daily activities at home soon as well. No major complications occurred, except one anastomotic leak. In terms of lung function, %FEV(1) was not changed whereas %VC was reduced significantly 1 month after surgery. All but two recurrences have been healthy without a relapse for a mean of 289 days. CONCLUSIONS: These results suggest that HALTS may be a useful surgical technique to reduce the invasiveness of conventional radical esophagectomy with three-field lymphadenectomy for thoracic esophageal cancer. 相似文献
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Gender difference in alcoholic liver injury] 总被引:1,自引:0,他引:1
Nobuyuki Enomoto Yoshiyuki Takei Shunhei Yamashina Kenichi Ikejima Satoko Suzuki Tsuneo Kitamura Nobuhiro Sato 《Nihon Arukōru Yakubutsu Igakkai zasshi》2004,39(3):163-167
Gender differences of alcoholic liver injury have been described previously, but mechanisms have only partially characterized. For example, it is known that females develop alcoholic liver injury more rapidly and to a greater extent than males. It now appears that estrogen participates in several aspects of this phenomenon. On the other hand, attention has been directed towards the effect of ethanol ingestion on Kupffer cell function, which is stimulated by gut-derived endotoxins via mechanisms dependent on increased gut permeability and the possible relationship between Kupffer cell and alcohol-induced liver injury. 相似文献
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