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21.
Prostaglandins and thromboxanes are important modulators of airway physiology. The synthesis of these mediators depends on two isoforms of cyclooxygenase (COX), constitutive COX-1 and inducible COX-2. COX-2 expression has been observed in various inflammatory diseases, but not all aspects of the expression and the role of COX-2 in conditions of allergic inflammation such as asthma are clear. In the present study, we examined the 72-h kinetics of the expression of COX-isoform mRNA in ovalbumin-sensitized and -challenged guinea-pig lungs. The sensitized animals showed a robust and transient induction of COX-2 mRNA expression within 1 h after ovalbumin challenge, whereas their COX-1 mRNA levels remained unchanged. Upregulation of the level and activity of COX-2 protein followed the induction of COX-2 mRNA. Lung slices harvested from ovalbumin-challenged animals released more prostaglandin D(2) and prostaglandin E(2) spontaneously or in response to A23187 (10 microM) ex vivo than did those from unchallenged animals. This response was significantly blocked by the COX-2 selective inhibitors, NS-398 and JTE-522. In vivo administration of NS-398 significantly inhibited the accumulation of eosinophils and neutrophils in the lungs. In conclusion, de novo COX-2 expression during allergic inflammation modifies prostanoid synthesis in the lung and airway pathophysiology.  相似文献   
22.
The systemic hemodynamic and coronary dilative responses to sublingual nitroglycerin were studied in patients receiving transdermal nitroglycerin. A total of 48 patients with coronary artery disease were divided into 4 groups: 12 patients receiving 1 tablet of sublingual nitroglycerin without transdermal nitroglycerin (Group 1), 12 patients receiving 1 tablet of sublingual nitroglycerin with 12-hour-daily intermittent therapy of transdermal nitroglycerin (Group 2), 12 patients receiving 1 tablet of sublingual nitroglycerin with continuous therapy of transdermal nitroglycerin (Group 3), and 12 patients receiving 2 tablets of sublingual nitroglycerin with continuous therapy of transdermal nitroglycerin (Group 4). Before and during administration of sublingual nitroglycerin, aortic pressure, left ventricular pressure, and coronary artery diameter were examined at diagnostic cardiac catheterization in all patients. During sublingual nitroglycerin, the decreases of aortic systolic pressure and left ventricular end-diastolic pressure were greater in Group 1, 2, and 4 than in Group 3. Dilation of coronary arteries by sublingual nitroglyerin tended to be greater in Group 1, 2, and 4 than in Group 3. Thus, the effects of sublingual nitroglycerin for the relief of ischemia might be more prominent in patients with intermittent therapy of transdermal nitroglycerin than in those with continuous therapy. The increased dose of sublingual nitroglycerin for the relief of ischemia might be more effective in patients with continuous therapy of transdermal nitroglycerin.  相似文献   
23.
We studied the effect of putrescine on acute liver failure caused in rats by two injections of 1 gm/kg D-galactosamine. The hepatic polyamine level rose only slightly in the D-galactosamine-injected rats treated with glucagon and insulin, and [3H]thymidine incorporation into DNA increased little; these hormones did not improve the survival rate. When D-galactosamine-injected rats were given putrescine, the putrescine concentration in the liver increased and the survival rate of the rats was significantly higher than that of control rats given only D-galactosamine. Putrescine administration tended to lower the serum level of alanine aminotransferase in rats injected with D-galactosamine, so the polyamine might have a protective effect on hepatocytes. Putrescine significantly increased [3H]thymidine incorporation in the liver; thus it accelerated liver regeneration. Difluoromethylornithine decreased the level of putrescine in the liver, decreasing both [3H]thymidine uptake and the survival rate. In the rats treated with D-galactosamine, in which liver damage was so severe that treatment with glucagon and insulin was ineffective, the intraperitoneal administration of putrescine increased the survival rate in acute liver failure. This probably resulted mainly from activation of liver regeneration and possibly from a protective effect of putrescine on the liver.  相似文献   
24.
Forty patients with either obstructive sleep apnea syndrome or a clinical complaint of daytime sleepiness with measured nocturnal increase in upper airway resistance and snoring were investigated during sleep for the presence of pulsus paradoxus, which is defined as a decrease in systolic blood pressure (SBP) of at least 10 mmHg during inspiration. Two thirds of the subjects presented pulsus paradoxus. Age, lowest oxygen saturation (SaO2), and negative inspiratory esophageal pressure nadir (an index of inspiratory effort) were the only studied variables which could statistically dissociate patients presenting pulsus paradoxus. We then divided the patient population into three different subgroups of equal number based upon the degree of decrease in SBP (i.e., >20 mmHg, <20 but >10 mmHg, and <10 mmHg). In this second analysis, age was the only significant variable that separated the three groups. Lowest SaO2 could not be used to statistically separate subjects with mild to moderate pulsus paradoxus from those without it; and negative inspiratory esophageal pressure measurements could only significantly identify subjects with severe pulsus paradoxus (i.e., >20 mmHg) from those without any pulsus paradoxus. The variable which correlated best with age was negative inspiratory esophageal pressure nadir (R = 0.83). Our interpretation is that as age increased, negative inspiratory esophagel pressure became less negative, due to the known impact of aging on muscles, and pulsus paradoxus was no longer observed. Offprint requests to: C. Guilleminault  相似文献   
25.
Journal of Gastroenterology - In clinical practice, rectal cancer (RC) is classified according to tumor location. However, RC’s genetic characteristics according to tumor location remain...  相似文献   
26.
27.
Inheritability of atherosclerosis and the influences of serum lipids on atherosclerosis were examined by following its progression in selectively bred WHHL rabbits. Our studies indicate (1) coronary atherosclerosis is clearly inherited from parents by offspring whereas inheritability of aortic atherosclerosis is uncertain; (2) coronary stenosis is positively correlated to serum cholesterol level, although the correlation coefficient is markedly low: in contrast, no relationship between serum lipid levels and aortic atherosclerosis was observed; (3) cholesterol-rich VLDL showed atherogenicity in aorta, but not in coronary arteries; (4) an unknown lipoprotein detected by 3.6% polyacrylamide gel electrophoresis was related to coronary atherosclerosis, although no relationship between the unknown lipoprotein and aortic atherosclerosis was observed. These findings suggest that there are two types of genetic factors involved in atherosclerosis, one of which is unique to coronary atherosclerosis whereas the other is related to only aortic atherosclerosis.  相似文献   
28.
29.
We present a very rare case of rectal cancer in a patient with situs inversus totalis (SIT), which is a complete transposition of the thoracic and abdominal viscera. A woman in her 60s visited a local hospital reporting bloody stool and was diagnosed with upper rectal cancer and SIT. We made careful preoperative preparations for the congenital anomaly, and robotic-assisted high anterior resection with D3 lymph node dissection was performed. Although we adopted an unusual six-port placement, the operation was performed safely and efficiently without any adverse events. The patient recovered uneventfully. The pathological specimen was classified as pT3N2bM0 with negative resection margins. Robotic-assisted surgery is advantageous for rectal cancer treatment even when anatomical abnormalities make the surgical procedure more difficult.  相似文献   
30.

Background

The goal of this study was to evaluate the short-term outcomes of robotic-assisted lateral lymph node dissection for patients with advanced lower rectal cancer.

Methods

Between 2012 and 2013, 50 consecutive patients underwent robotic-assisted lateral lymph node dissection for rectal cancer in Shizuoka Cancer Center Hospital. Perioperative outcomes including operative time, operative blood loss, length of stay, postoperative complications, and histopathological data were collected prospectively.

Results

Median patient age was 62 years (range 36–74 years). Operative procedures included low anterior resections (n = 27), intersphincteric resections (n = 16), and abdominoperineal resections (n = 7). Bilateral lymph node dissection was performed in 44 patients. The median operative time was 476 min (range 320–683 min), and the median time required for lateral lymph node dissection was 165 min (range 85–257 min). The median blood loss was 27 mL (range 5–690 mL). There were no cases of open surgery or laparoscopic conversion. The median duration of postoperative hospital stay was 8 days (range 6–13 days). Clavien–Dindo classification Grade III–IV complications occurred in only one patient (2.0 %). There were no cases of anastomotic leak. There was no perioperative mortality. The median number of harvested lateral lymph nodes was 19 (range 5–47).

Conclusions

Robotic-assisted lateral lymph node dissection is a safe, feasible, and useful approach for patients with advanced lower rectal cancer.
  相似文献   
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