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71.
Aromatase is an enzyme complex that is composed of a specific form of cytochrome P-450 and a flavoprotein, NADPH-cytochrome P-450 reductase. Aromatase activity of granulosa cells is increased markedly by follicle-stimulating hormone (FSH) and by analogs of cyclic AMP. It was the objective of the present study to investigate the effects of FSH and dibutyryl cyclic AMP (Bt2cAMP) on the synthesis of NADPH-cytochrome P-450 reductase in rat granulosa cells maintained in vitro. Granulosa cells were obtained from the ovaries of diethylstilbestrol (DES)-treated immature rats and were incubated in the presence of DES (10−7 M), DES + FSH (250 ng/ml), or DES + Bt2cAMP (1 mM) for up to 72 h. After 72 h of incubation, aromatase activity of cells incubated with DES alone was 5 pmoles estrogen formed 2 h−1 mg−1 protein and was increased > 60-fold in cells incubated with FSH or Bt2cAMP. NADPH-cytochrome P-450 reductase was immunoisolated from [35S]methionine-labeled lysates of granulosa cells incubated for 72 h in the absence or presence of stimulatory factors. The rate of synthesis of reductase was found to be increased about 3-fold in cells incubated with DES + FSH or DES + Bt2cAMP as compared to cells incubated with DES alone. By immunoblot analysis we found that the cellular content of reductase was increased about 2-fold by FSH and Bt2cAMP treatment. Reductase specific activity was 10 nmoles min−1 mg−1 protein in membrane fractions of DES-treated cells and was increased 1.6-fold by FSH treatment. These findings are indicative that FSH increases the rate of synthesis, cellular content and specific activity of NADPH-cytochrome P-450 reductase in rat granulosa cells in vitro. The finding that Bt2cAMP causes a similar induction of reductase synthesis is suggestive that the stimulatory effect of FSH on this component of the aromatase enzyme complex is mediated by an increase in cyclic AMP formation.  相似文献   
72.

Background

To establish quicker cardiac arrest and less myocardial distension injury during heart procurement, we combined St. Thomas and histidine-tryptophan-ketoglutarate (HTK) solutions for donor heart preservation since June 2008.

Methods

From June 2008 to March 2010, we enrolled 31 heart transplantation (HT) patients in this study. During heart procurement we initially infused 1,000 mL cold St Thomas cardioplegic solution to achieve cardiac arrest. After procurement, a further 2,000 mL of cold HTK solution was infused at low perfusion pressure. Another 1,000 mL cold HTK solution was perfused before donor heart implantation. We examined donor age, recipient preoperative characteristics, ischemia time, hospital stay, postoperative graft function, major cardiac events, and transplant vasculopathy (TCAD).

Results

Twenty-two patients (71.0%) presented with dilated cardiomyopathy and 7 (23.3%) with ischemia cardiomyopathy. There were 23 (76.7%) male donors, and the mean donor age was 38.4 ± 13.8 years. Six patients underwent a redo sternotomy, 1 patient needed a third-do sternotomy, and 1 a seventh sternotomy (third HT) for repeated endocarditis and graft failure. The average ischemia time was 224.9 ± 71.0 minutes and the postoperative hospital stay was 57.7 ± 47.7 days. The surgical mortality (3.2%) was not accompanied by hospital or follow-up mortality. Patient left ventricular ejection fraction postoperative was 59.6 ± 2.3% with good functional status. Major cardiac events occurred in 8 patients (26.7%) without major complications. There were two subjects with TCAD but normal graft function. The correlation between ischemia time and hospital stay was insignificant (r = 0.21; P = .26).

Conclusions

Donor heart preservation combining St Thomas cardioplegic arest and low-pressure perfusion with HTK solution seemed to be safe with. short-term survival similar to other approaches.  相似文献   
73.

Background

Obesity accelerates pancreatic cancer growth; the mechanisms underlying this association are poorly understood. This study evaluated the hypothesis that obesity, rather than high-fat diet, is responsible for accelerated pancreatic cancer growth.

Methods

Male C57BL/6J mice were studied after 19?weeks of high-fat (60?% fat; n?=?20) or low-fat (10?% fat; n?=?10) diet and 5?weeks of Pan02 murine pancreatic cancer growth (flank).

Results

By two-way ANOVA, diet did not (p?=?0.58), but body weight, significantly influenced tumor weight (p?=?0.01). Tumor weight correlated positively with body weight (R 2?=?0.562; p?<?0.001). Tumors in overweight mice were twice as large as those growing in lean mice (1.2?±?0.2?g vs. 0.6?±?.01?g, p?<?0.01), had significantly fewer apoptotic cells than those in lean mice (0.8?±?0.4 vs 2.4?±?0.5; p?<?0.05), and greater adipocyte volume (3.7 vs. 2.2?%, p?<?0.05). Apoptosis (R 2?=?0.472; p?=?0.008) and serum adiponectin correlated negatively with tumor weight (R?=?0.45; p?<?0.05).

Conclusions

These data suggest that body weight, and not high-fat diet, is responsible for accelerated murine pancreatic cancer growth observed in this model of diet-induced obesity. Decreased tumor apoptosis appears to play an important mechanistic role in this process. The concept that decreased apoptosis is potentiated by hypoadiponectinemia (seen in obesity) deserves further investigation.  相似文献   
74.
Hyperphosphatemia has been associated with the development of secondary hyperparathyroidism, renal osteodystrophy, cardiovascular calcification and increased risk of death. Using a one group, pretest-posttest study design, we sought to evaluate changes in serum phosphorus, calcium, parathyroid hormone and subject knowledge in response to a 3-month educational intervention. Mean serum phosphorus levels did not differ significantly between the three evaluation periods: pretreatment (5.69 mg/dl), treatment (5.84 mg/dl) and posttreatment (6.17 mg/dl). Mean serum calcium, calcium-phosphorus product and PTH values also did not differ significantly between the treatment periods. We observed no difference between the subject test scores between the two testing periods. Calcium-phosphorus product, serum phosphorus and PTH values on average, despite the education program, remained outside the K/DOQI target guidelines 44, 56 and 81% of the time, respectively. The results of this study suggest that an aggressive 3-month patient education program targeting dietary phosphorus knowledge, phosphate binder name and dosing, and knowledge of medical consequences associated with non-compliance had no effect on the serum phosphorus, calcium, PTH or phosphate binder need.  相似文献   
75.
Changing management of gallstone disease during pregnancy   总被引:3,自引:4,他引:3  
Background: Symptomatic gallstones may be problematic during pregnancy. The advisability of laparoscopic cholecystectomy (LC) is uncertain. The objective of this study is to define the natural history of gallstone disease during pregnancy and evaluate the safety of LC during pregnancy. Methods: Review of medical records of all pregnant patients with gallstone disease at the University of California, San Francisco, from 1980 to 1996. Results: Of approximately 29,750 deliveries, 47 (0.16%) patients were treated for gallstone disease, including biliary colic in 33, acute cholecystitis in 12, and pancreatitis in two. Conservative treatment was attempted in all patients but failed in 17 (36%) cases. Two patients required combined preterm Cesarean-section cholecystectomy and 10 required surgery in the early postpartum period for persistent symptoms. Seventeen patients required cholecystectomy during pregnancy for biliary colic (10), acute cholecystitis (six), and pancreatitis (one). Three patients were treated with open cholecystectomy. Fourteen patients underwent LC at a mean gestational age of 18.6 weeks, mean OR time of 74 min, and mean length of stay of 1.2 days. Hasson cannulation was utilized in 11 patients. Reduced-pressure pneumoperitoneum (6–10 mmHg) was used in seven patients. Prophylactic tocolytics were used in seven patients, with transient postoperative preterm labor observed in one. There were no open conversions, preterm deliveries, fetal loss, teratogenicity, or maternal morbidity. Conclusions: In past years, symptomatic gallstones during pregnancy were managed conservatively or with open cholecystectomy. LC is a feasible and safe method for treating severely symptomatic patients. Received: 3 April 1997/Accepted: 5 July 1997  相似文献   
76.
OBJECTIVE: The development of acute renal failure following cardiac surgery is a rare but devastating complication with high morbidity and mortality. This study aimed to assess the incidence of acute renal failure necessitating continuous renal replacement therapy (CRRT) in patients who required cardiopulmonary bypass, to determine the factors associated with mortality and to evaluate long-term outcome. METHODS: Patients who underwent cardiac surgery between October 1997 and 2003 and treated with CRRT were included (n=98). Six patients were then excluded (already in established renal failure pre-operatively) and one patient lost to follow-up. A retrospective analysis was carried out. RESULTS: Overall CRRT was used in 2.9% (92/3172). The mean (SD) age of patients was 68 (10) years. Their mean pre-operative creatinine level and duration of cardiopulmonary bypass were 154 (87)micromol/l and 160 (84)min, respectively. Mean duration from surgery to establishment of CRRT was 50 (42)h. Mean creatinine level prior to hospital discharge was 168 (93)micromol/l. Thirty-day mortality was 42%. Significant risk factors for death were complex procedures (odds ratio=9.9), gastro-intestinal complications (OR=7.2), cross-clamp time over 88min (OR=5.9), re-exploration (OR=4.0) and patients age over 75 years (OR=3.3). Actuarial 1 and 5-year survivals (95% CI) were 53 (43, 63) % and 52 (42, 62) %, respectively. Only 2 (2.2%) patients required long term renal support. CONCLUSIONS: Acute renal failure necessitating the use of CRRT is a rare but serious complication post cardiopulmonary bypass. In the long-term, surviving patients are not likely to require further renal support.  相似文献   
77.
Objective:  Epithelioid angiomyolipoma (EAML) is a rare malignant variant of renal angiomyolipoma (AML). There were 34 cases of EAML reported in 25 studies (including this present study) over the past decade. About 68% were females and 32% males. The mean age was 40.1 years, 53% developed metastatic disease after nephrectomy, and eight patients had TSC. All cases are reported positive when stained with HMB-45 which also labels all classical AML. This study evaluates the use of Ki-67 (proliferation marker) in the pathological diagnosis of EAML and distinction from classical AML. Method:  Immunohistochemical reactions for Ki-67 were generated on multiple representative blocks of tissue obtained from two cases of HMB-45 positive EAML and four cases of classic AML and the percentage of positively staining cells estimated. Results:  Both cases of EAML were strongly positive for Ki-67 while all four classic AML were completely negative. Conclusion:  The Ki67 is a useful marker in which distinguishes the malignant epithelioid variant of AML from classic AML.  相似文献   
78.
Sex differences in the foramen magnum region of the cranial base have been identified with varying rates of success. Recent publications demonstrate a continuing strong interest in metric analysis of the foramen magnum region for sex determination despite the generally low expression of cranial base sexual dimorphism. It is important to identify possible age effects on skull base morphometric variables as most reported discriminant analyses use pooled-age samples without assessing the influence of aging on sexual dimorphism. This study examined 135 adult cranial bases (69 males and 66 females) from the St. Bride’s documented skeletal collection in London. Traditional craniometric measurements were recorded and the effect of age on sexual dimorphism of this anatomical region was tested using a variety of statistical analyses including MANOVA and discriminant function analysis. Age-dependent discriminant functions for <50 and >50 years of age were developed and compared. The cross-validated results showed that the <50 years function determined the sex of 69.1 % correctly while the >50 years function achieved 81.3 % correct predictions. However, the high sex biases of these functions (14.4 % and ?17.5 %) severely limit their practical application. A pooled-age discriminant function permitted 71.9 % correct prediction with a sex bias of only ?1.7 %. The statistical analyses also showed no significant age effect on any of the variables, suggesting that a separation by age is not necessary for the development of sex determination methods.  相似文献   
79.
PURPOSE: The impact of malpractice awards on insurance premiums and health care delivery generates much concern. To our knowledge no data exist regarding the impact of caps, or upper limits, on awards for noneconomic damages (also termed pain and suffering) on health care delivery patterns or outcomes. We investigated the effect of caps on the use of and outcomes following aggressive surgical treatment (radical cystectomy) in patients with bladder cancer. MATERIALS AND METHODS: We performed a retrospective cohort study of patients with bladder cancer who underwent radical cystectomy, identified from the Surveillance, Epidemiology, and End Results (SEER) Program database. Cystectomy rates and post-cystectomy disease specific survival were compared between SEER regions with and without a cap, while controlling for other variables. RESULTS: A significantly greater proportion of patients with stages III and IV bladder cancer underwent cystectomy in SEER regions with a cap. Cap status was a significant predictor of survival from bladder cancer. CONCLUSIONS: Radical cystectomy for bladder cancer is performed more often even for advanced bladder cancer in geographic regions with a cap with a positive impact on survival. The institution of caps may have beneficial effects on patterns of health care beyond that of merely decreasing insurance premium costs.  相似文献   
80.
Fulminant hepatic failure (FHF) is a rare but often fatal disease in children. Clinical and laboratory predictors of liver regeneration and recovery, however, have not been well established. We hypothesized that hypophosphatemia may indicate recovery of liver synthetic function in children with FHF. We retrospectively reviewed the medical records of children with FHF who were admitted to UCLA and recovered hepatic function either spontaneously or by liver transplantation (LTx). Serum phosphate (Ph) and prothrombin time or international normalized ratio (INR) were compared over the patient's clinical course. Records of 39 children who spontaneously recovered experienced profound hypophosphatemia that resolved as liver synthetic function improved. Similar patterns were seen in the 84 children who recovered after LTx. We found that hypophosphatemia precedes the recovery of liver synthetic function in children with FHF who recovered with or without transplantation, and that Ph levels return to normal as liver synthetic function improves. These data suggest that hypophosphatemia may be a useful laboratory indicator of recovering liver function in children with FHF.  相似文献   
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